Hepatitis C Virus Resistance to Direct-Acting Antiviral Drugs in Interferon-Free Regimens.

PubMed

Pawlotsky, Jean-Michel

2016-07-01

Treatment of hepatitis C virus (HCV) infection has progressed considerably with the approval of interferon-free, direct-acting antiviral (DAA)-based combination therapies. Although most treated patients achieve virological cure, HCV resistance to DAAs has an important role in the failure of interferon-free treatment regimens. The presence of viral variants resistant to NS5A inhibitors at baseline is associated with lower rates of virological cure in certain groups of patients, such as those with genotype 1a or 3 HCV, those with cirrhosis, and/or prior nonresponders to pegylated interferon-based regimens. DAA-resistant HCV is generally dominant at virological failure (most often relapse). Viruses resistant to NS3-4A protease inhibitors disappear from peripheral blood in a few weeks to months, whereas NS5A inhibitor-resistant viruses persist for years. Re-treatment options are available, but first-line treatment strategies should be optimized to efficiently prevent treatment failure due to HCV resistance. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Sequencing of hepatitis C virus for detection of resistance to direct-acting antiviral therapy: A systematic review.

PubMed

Bartlett, Sofia R; Grebely, Jason; Eltahla, Auda A; Reeves, Jacqueline D; Howe, Anita Y M; Miller, Veronica; Ceccherini-Silberstein, Francesca; Bull, Rowena A; Douglas, Mark W; Dore, Gregory J; Harrington, Patrick; Lloyd, Andrew R; Jacka, Brendan; Matthews, Gail V; Wang, Gary P; Pawlotsky, Jean-Michel; Feld, Jordan J; Schinkel, Janke; Garcia, Federico; Lennerstrand, Johan; Applegate, Tanya L

2017-07-01

The significance of the clinical impact of direct-acting antiviral (DAA) resistance-associated substitutions (RASs) in hepatitis C virus (HCV) on treatment failure is unclear. No standardized methods or guidelines for detection of DAA RASs in HCV exist. To facilitate further evaluations of the impact of DAA RASs in HCV, we conducted a systematic review of RAS sequencing protocols, compiled a comprehensive public library of sequencing primers, and provided expert guidance on the most appropriate methods to screen and identify RASs. The development of standardized RAS sequencing protocols is complicated due to a high genetic variability and the need for genotype- and subtype-specific protocols for multiple regions. We have identified several limitations of the available methods and have highlighted areas requiring further research and development. The development, validation, and sharing of standardized methods for all genotypes and subtypes should be a priority. ( Hepatology Communications 2017;1:379-390).

Rapid reversal of innate immune dysregulation in blood of patients and livers of humanized mice with HCV following DAA therapy

PubMed Central

Burchill, Matthew A.; Roby, Justin A.; Crochet, Nanette; Wind-Rotolo, Megan; Stone, Amy E.; Edwards, Michael G.; Dran, Rachael J.; Kriss, Michael S.; Gale, Michael

2017-01-01

Chronic hepatitis C virus (HCV) infection results in sustained immune activation in both the periphery and hepatic tissue. HCV infection induces innate immune signaling that is responsible for recognition of dsRNA, leading to activation of transcription factors and production of Type I and III IFNs, as well as pro-inflammatory cytokines and chemokines. Continued activation of host-immune mediated inflammation is thought to contribute to pathologic changes that result in progressive hepatic fibrosis. The current standard treatment for chronic HCV infection is directly-acting antivirals (DAAs), which have provided the unique opportunity to determine whether successful, rapid treatment-induced eradication of viral RNA normalizes the dysregulated antiviral innate immune response in patients chronically infected with HCV. Results First, in patients receiving two different combinations of DAAs, we found that DAAs induced not only rapid viral clearance, but also a re-setting of antiviral immune responses in the peripheral blood. Specifically, we see a rapid decline in the expression of genes associated with chronic IFN stimulation (IFIT3, USP18, IFIT1) as well as a rapid decline in genes associated with inflammation (IL1β, CXCL10, CXCL11) in the peripheral blood that precedes the complete removal of virus from the blood. Interestingly, this rapid reversal of innate immune activation was not seen in patients who successfully clear chronic HCV infection using IFN-based therapy. Next, using a novel humanized mouse model (Fah-/-RAG2-/-IL2rgnull—FRG), we assessed the changes that occur in the hepatic tissue following DAA treatment. DAA-mediated rapid HCV clearance resulted in blunting of the expression of proinflammatory responses while functionally restoring the RIG-I/MAVS axis in the liver of humanized mice. Conclusions Collectively, our data demonstrate that the rapid viral clearance following treatment with DAAs results in the rebalancing of innate antiviral response in

Use of HCV+ Donors Does Not Affect HCV Clearance With Directly Acting Antiviral Therapy But Shortens the Wait Time to Kidney Transplantation.

PubMed

Sawinski, Deirdre; Patel, Nikunjkumar; Appolo, Brenda; Bloom, Roy

2017-05-01

Hepatitis C virus (HCV) infection is prevalent in the renal transplant population but direct acting antiviral agents (DAA) provide an effective cure of HCV infection without risk of allograft rejection. We report our experience treating 43 renal transplant recipients with 4 different DAA regimens. One hundred percent achieved a sustained viral response by 12 weeks after therapy, and DAA regimens were well tolerated. Recipients transplanted with a HCV+ donor responded equally well to DAA therapy those transplanted with a kidney from an HCV- donor, but recipients of HCV+ organs experienced significantly shorter wait times to transplantation, 485 days (interquartile range, 228-783) versus 969 days (interquartile range, 452-2008; P = 0.02). On this basis, we advocate for a strategy of early posttransplant HCV eradication to facilitate use of HCV+ organs whenever possible. Additional studies are needed to identify the optimal DAA regimen for kidney transplant recipients, accounting for efficacy, timing relative to transplant, posttransplant clinical outcomes, and cost.

Cost-effectiveness of hepatitis C treatment using generic direct-acting antivirals available in India

PubMed Central

Aggarwal, Rakesh; Chen, Qiushi; Goel, Amit; Seguy, Nicole; Pendse, Razia; Ayer, Turgay

2017-01-01

Background & aims Availability of directly-acting antivirals (DAAs) has changed the treatment landscape of hepatitis C virus (HCV) infection. The high price of DAAs has restricted their use in several countries. However, in some countries such as India, generic DAAs are available at much cheaper price. This study examined whether generic DAAs could be cost-saving and how long it would take for the treatment to become cost-saving/effective. Methods A previously-validated, mathematical model was adapted to the HCV-infected population in India to compare the outcomes of no treatment versus treatment with DAAs. Model parameters were estimated from published studies. Cost-effectiveness of HCV treatment using available DAAs was calculated, using a payer’s perspective. We estimated quality-adjusted life years (QALYs), disability-adjusted life years (DALYs), total costs, and incremental cost-effectiveness ratio of DAAs versus no treatment. One-way and probabilistic sensitivity analyses were conducted. Results Compared with no treatment, the use of generic DAAs in Indian HCV patients would increase the life expectancy by 8.02 years, increase QALYs by 3.89, avert 19.07 DALYs, and reduce the lifetime healthcare costs by $1,309 per-person treated. Treatment became cost-effective within 2 years, and cost-saving within 10 years of its initiation overall and within 5 years in persons with cirrhosis. Treating 10,000 HCV-infected persons could prevent 3400–3850 decompensated cirrhosis, 1800–2500 HCC, and 4000–4550 liver-related deaths. The results were sensitive to the costs of DAAs, pre- and post-treatment diagnostic tests and management of cirrhosis, and quality of life after sustained virologic response. Conclusions Treatment with generic DAAs available in India will improve patient outcomes, provide a good value for money within 2 years, and be ultimately cost-saving. Therefore, in this and similar settings, HCV treatment should be a priority from a public health as

Quantifying antiviral activity optimizes drug combinations against hepatitis C virus infection.

PubMed

Koizumi, Yoshiki; Ohashi, Hirofumi; Nakajima, Syo; Tanaka, Yasuhito; Wakita, Takaji; Perelson, Alan S; Iwami, Shingo; Watashi, Koichi

2017-02-21

With the introduction of direct-acting antivirals (DAAs), treatment against hepatitis C virus (HCV) has significantly improved. To manage and control this worldwide infectious disease better, the "best" multidrug treatment is demanded based on scientific evidence. However, there is no method available that systematically quantifies and compares the antiviral efficacy and drug-resistance profiles of drug combinations. Based on experimental anti-HCV profiles in a cell culture system, we quantified the instantaneous inhibitory potential (IIP), which is the logarithm of the reduction in viral replication events, for both single drugs and multiple-drug combinations. From the calculated IIP of 15 anti-HCV drugs from different classes [telaprevir, danoprevir, asunaprevir, simeprevir, sofosbuvir (SOF), VX-222, dasabuvir, nesbuvir, tegobuvir, daclatasvir, ledipasvir, IFN-α, IFN-λ1, cyclosporin A, and SCY-635], we found that the nucleoside polymerase inhibitor SOF had one of the largest potentials to inhibit viral replication events. We also compared intrinsic antiviral activities of a panel of drug combinations. Our quantification analysis clearly indicated an advantage of triple-DAA treatments over double-DAA treatments, with triple-DAA treatments showing enhanced antiviral activity and a significantly lower probability for drug resistance to emerge at clinically relevant drug concentrations. Our framework provides quantitative information to consider in designing multidrug strategies before costly clinical trials.

Restrictions for reimbursement of interferon-free direct-acting antiviral drugs for HCV infection in Europe.

PubMed

Marshall, Alison D; Cunningham, Evan B; Nielsen, Stine; Aghemo, Alessio; Alho, Hannu; Backmund, Markus; Bruggmann, Philip; Dalgard, Olav; Seguin-Devaux, Carole; Flisiak, Robert; Foster, Graham R; Gheorghe, Liana; Goldberg, David; Goulis, Ioannis; Hickman, Matthew; Hoffmann, Patrick; Jancorienė, Ligita; Jarcuska, Peter; Kåberg, Martin; Kostrikis, Leondios G; Makara, Mihály; Maimets, Matti; Marinho, Rui Tato; Matičič, Mojca; Norris, Suzanne; Ólafsson, Sigurður; Øvrehus, Anne; Pawlotsky, Jean-Michel; Pocock, James; Robaeys, Geert; Roncero, Carlos; Simonova, Marieta; Sperl, Jan; Tait, Michele; Tolmane, Ieva; Tomaselli, Stefan; van der Valk, Marc; Vince, Adriana; Dore, Gregory J; Lazarus, Jeffrey V; Grebely, Jason

2018-02-01

All-oral direct-acting antiviral drugs (DAAs) for hepatitis C virus, which have response rates of 95% or more, represent a major clinical advance. However, the high list price of DAAs has led many governments to restrict their reimbursement. We reviewed the availability of, and national criteria for, interferon-free DAA reimbursement among countries in the European Union and European Economic Area, and Switzerland. Reimbursement documentation was reviewed between Nov 18, 2016, and Aug 1, 2017. Primary outcomes were fibrosis stage, drug or alcohol use, prescriber type, and HIV co-infection restrictions. Among the 35 European countries and jurisdictions included, the most commonly reimbursed DAA was ombitasvir, paritaprevir, and ritonavir, with dasabuvir, and with or without ribavirin (33 [94%] countries and jurisdictions). 16 (46%) countries and jurisdictions required patients to have fibrosis at stage F2 or higher, 29 (83%) had no listed restrictions based on drug or alcohol use, 33 (94%) required a specialist prescriber, and 34 (97%) had no additional restrictions for people co-infected with HIV and hepatitis C virus. These findings have implications for meeting WHO targets, with evidence of some countries not following the 2016 hepatitis C virus treatment guidelines by the European Association for the Study of Liver. Copyright © 2018 Elsevier Ltd. All rights reserved.

Decrease of Alpha-fetoprotein in Patients with Cirrhosis Treated with Direct-acting Antivirals.

PubMed

Nguyen, Kelvin; Jimenez, Melissa; Moghadam, Nima; Wu, Crystal; Farid, Alex; Grotts, Jonathan; Elashoff, David; Choi, Gina; Durazo, Francisco A; El-Kabany, Mohamed M; Han, Steven-Huy B; Saab, Sammy

2017-03-28

Background and Aims: The lack of specificity has limited the role of serum alpha-fetoprotein (AFP) for hepatocellular carcinoma (HCC) screening among patients with cirrhosis related to hepatitis C virus (HCV) infection. We sought to examine whether AFP may decrease after achieving a sustained virological response (SVR) in patients with HCV-related cirrhosis. Methods: We performed a retrospective study of patients with HCV-related cirrhosis who were cured with direct-acting antiviral (DAA) therapy at the University of California, Los Angeles. Laboratory values, including serum AFP, were measured before and after completing the DAA treatment. Results: Fifty-six patients met the inclusion criteria, with median (interquartile range [IQR]) age of 67 (58-69) years and with 51.8% being male. All patients received DAA therapy without interferon. AFP decreased from median (IQR) 7.2 (4.2-13.4) ng/mL before DAAs to 4.2 (2.7-6.3) ng/mL at the end of treatment and 4.2 (2.9-6.8) ng/mL at 12 weeks after treatment ( p < 0.001). Model for end-stage liver disease (MELD), fibrosis-4 (FIB4), and aspartate transaminase (AST) to platelet ratio index (APRI) scores at baseline were not significantly associated with AFP reduction. On multivariate analysis, platelet count, AST and total bilirubin at baseline were significantly correlated to AFP reduction ( p = 0.04, 0.009 and 0.04, respectively). The higher the baseline AFP, the greater the reduction in AFP. There was no statistically significant correlation between baseline AFP and MELD, FIB4 or APRI scores. Conclusion: There was a significant decrease in AFP in patients with cirrhosis who achieved a SVR with DAAs. Given a reduction in AFP after DAA treatment, AFP should be further studied as a screening modality for HCC in patients with cirrhosis.

Reactivation of Herpesvirus in Patients With Hepatitis C Treated With Direct-Acting Antiviral Agents.

PubMed

Perelló M, Christie; Fernández-Carrillo, Carlos; Londoño, María-Carlota; Arias-Loste, Teresa; Hernández-Conde, Marta; Llerena, Susana; Crespo, Javier; Forns, Xavier; Calleja, José Luis

2016-11-01

We performed a case-series analysis of reactivation of herpesvirus in patients with hepatitis C virus (HCV) infection treated with direct-acting antiviral (DAA) agents. We collected data from 576 patients with HCV infection treated with DAA combinations at 3 hospitals in Spain, from November 2014 through November 2015. We also collected data from a control population (230 HCV-infected patients, matched for sex and age; 23 untreated and 213 treated with interferon-based regimens). Herpesvirus was reactivated in 10 patients who received DAA therapy (7 patients had cirrhosis and 3 patients had received liver transplants), a median of 8 weeks after the therapy was initiated. None of the controls had herpesvirus reactivation. Patients with herpesvirus reactivation were receiving the DAA agents sofosbuvir with ledipasvir (with or without ribavirin, 7/10), ombitasvir with paritaprevir and ritonavir plus dasabuvir (with or without ribavirin, 2/10), or sofosbuvir with simeprevir plus ribavirin (1/10). Two of the 10 patients developed postherpetic neuralgia and 1 patient developed kerato-uveitis. All 10 patients with herpesvirus reactivation achieved a sustained virologic response. Immune changes that follow clearance of HCV might lead to reactivation of other viruses, such as herpesvirus. Patients with HCV infection suspected of having herpesvirus infection should be treated immediately. Some groups also might be screened for herpesvirus infection. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Retreatment of patients with treatment failure of direct-acting antivirals: Focus on hepatitis C virus genotype 1b.

PubMed

Kanda, Tatsuo; Nirei, Kazushige; Matsumoto, Naoki; Higuchi, Teruhisa; Nakamura, Hitomi; Yamagami, Hiroaki; Matsuoka, Shunichi; Moriyama, Mitsuhiko

2017-12-14

The recent development of direct-acting antiviral agents (DAAs) against hepatitis C virus (HCV) infection could lead to higher sustained virological response (SVR) rates, with shorter treatment durations and fewer adverse events compared with regimens that include interferon. However, a relatively small proportion of patients cannot achieve SVR in the first treatment, including DAAs with or without peginterferon and/or ribavirin. Although retreatment with a combination of DAAs should be conducted for these patients, it is more difficult to achieve SVR when retreating these patients because of resistance-associated substitutions (RASs) or treatment-emergent substitutions. In Japan, HCV genotype 1b (GT1b) is founded in 70% of HCV-infected individuals. In this minireview, we summarize the retreatment regimens and their SVR rates for HCV GT1b. It is important to avoid drugs that target the regions targeted by initial drugs, but next-generation combinations of DAAs, such as sofosbuvir/velpatasvir/voxilaprevir for 12 wk or glecaprevir/pibrentasvir for 12 wk, are proposed to be potential solution for the HCV GT1b-infected patients with treatment failure, mainly on a basis of targeting distinctive regions. Clinicians should follow the new information and resources for DAAs and select the proper combination of DAAs for the retreatment of HCV GT1b-infected patients with treatment failure.

Hepatitis C virus pharmacogenomics in Latin American populations: implications in the era of direct-acting antivirals

PubMed Central

Trinks, Julieta; Caputo, Mariela; Hulaniuk, María L; Corach, Daniel; Flichman, Diego

2017-01-01

In recent years, great progress has been made in the field of new therapeutic options for hepatitis C virus (HCV) infection. The new direct-acting antiviral agents (DAAs) represent a great hope for millions of chronically infected individuals because their use may lead to excellent cure rates with fewer side effects. In Latin America, the high prevalence of HCV genotype 1 infection and the significant association of Native American ancestry with risk predictive single-nucleotide polymorphisms (SNPs) in IFNL4 and ITPA genes highlight the need to implement new treatment regimens in these populations. However, the universal accessibility to DAAs is still not a reality in the region as their high cost is one of the major, although not the only, limiting factors for their broad implementation. Therefore, under these circumstances, could the assessment of host genetic markers be a useful tool to prioritize DAA treatment until global access to these new drugs can be achieved? This review will summarize the scientific evidences and the potential implications of HCV pharmacogenomics in this rapidly evolving era of anti-HCV drug development. PMID:28405170

Direct-Acting Antivirals in Chronic Hepatitis C Genotype 4 Infection in Community Care Setting.

PubMed

Gayam, Vijay; Khalid, Mazin; Mandal, Amrendra Kumar; Hussain, Muhammad Rajib; Mukhtar, Osama; Gill, Arshpal; Garlapati, Pavani; Shrestha, Binav; Guss, Debra; Sherigar, Jagannath; Mansour, Mohammed; Mohanty, Smruti

2018-04-01

Limited data exists comparing the safety, tolerability, and efficacy of direct-acting antivirals (DAAs) in patients with chronic hepatitis C genotype 4 (HCV GT-4) in the community practice setting. We aim to evaluate the treatment response of DAAs in these patients. All the HCV GT-4 patients treated with DAAs between January 2014 and October 2017 in a community clinic setting were retrospectively analyzed. Pretreatment baseline patient characteristics, treatment efficacy with sustained virologic response (SVR) at 12 weeks post treatment (SVR12), and adverse reactions were assessed. Fifty-two patients of Middle Eastern (primarily Egyptian) descent were included in the study. Thirty-two patients were treated with ledipasvir/sofosbuvir (Harvoni ® ) ± ribavirin, 12 patients were treated with ombitasvir/paritaprevir/ritonavir/dasabuvir (ViekiraPak ® ) ± ribavirin, and eight patients were treated with sofosbuvir/Velpatasvir (Epclusa ® ). Ten patients (19.2%) had compensated cirrhosis. Overall, SVR at 12 weeks was achieved in 94% in patients who received one of the three DAA regimens (93.8% in Harvoni ® group, 91.7 % in ViekiraPak ® group and 100% in Epclusa ® group). Prior treatment status and type of regimen used in the presence of compensated cirrhosis had no statistical significance on overall SVR achievement (P value = 0.442 and P value = 0.091, respectively). The most common adverse effect was fatigue (27%). In the real-world setting, DAAs are effective and well tolerated in patients with chronic HCV GT-4 infection with a high overall SVR rate of 94%. Large-scale studies are needed to further assess this SVR in these groups.

A population approach to disease management: hepatitis C direct-acting antiviral use in a large health care system.

PubMed

Belperio, Pamela S; Backus, Lisa I; Ross, David; Neuhauser, Melinda M; Mole, Larry A

2014-06-01

The introduction of the first direct-acting antiviral agents (DAAs) for the treatment of hepatitis C virus (HCV), telaprevir and boceprevir, marked a unique event in which 2 disease-changing therapies received FDA approval at the same time. Comparative safety and effectiveness data in real-world populations upon which to make formulary decisions did not exist. To describe the implementation, measurement, and outcomes of an enduring population-based approach of surveillance of medication management for HCV. The foundation of the population approach to HCV medication management used by the Department of Veterans Affairs (VA) relied upon a basic framework of (a) providing data for effective regional and local management, (b) education and training, (c) real-time oversight and feedback from a higher organization level, and (d) prompt outcome sharing. These population-based processes spanned across the continuum of the direct-acting antiviral oversight process. We used the VA's HCV Clinical Case Registry-which includes pharmacy, laboratory, and diagnosis information for all HCV-infected veterans from all VA facilities-to assess DAA treatment eligibility, DAA uptake and timing, appropriate use of DAAs including HCV RNA monitoring and medication possession ratios (MPR), nonconcordance with guidance for adjunct erythropoiesis-stimulating agent (ESA) and granulocyte colony-stimulating factor (GCSF) use, hematologic adverse effects, discontinuation rates, and early and sustained virologic responses. Training impact was assessed via survey and change in pharmacist scope of practice. One year after FDA approval, DAAs had been prescribed at 120 of 130 VA facilities. Over 680 VA providers participated in live educational training programs including 380 pharmacists, and pharmacists with a scope of practice for HCV increased from 59 to 110 pharmacists (86%). HCV RNA futility testing improved such that only 1%-3% of veterans did not have appropriate testing compared with 15%-17% 6

Direct-Acting Antivirals in Chronic Hepatitis C Genotype 4 Infection in Community Care Setting

PubMed Central

Gayam, Vijay; Khalid, Mazin; Mandal, Amrendra Kumar; Hussain, Muhammad Rajib; Mukhtar, Osama; Gill, Arshpal; Garlapati, Pavani; Shrestha, Binav; Guss, Debra; Sherigar, Jagannath; Mansour, Mohammed; Mohanty, Smruti

2018-01-01

Background Limited data exists comparing the safety, tolerability, and efficacy of direct-acting antivirals (DAAs) in patients with chronic hepatitis C genotype 4 (HCV GT-4) in the community practice setting. We aim to evaluate the treatment response of DAAs in these patients. Methods All the HCV GT-4 patients treated with DAAs between January 2014 and October 2017 in a community clinic setting were retrospectively analyzed. Pretreatment baseline patient characteristics, treatment efficacy with sustained virologic response (SVR) at 12 weeks post treatment (SVR12), and adverse reactions were assessed. Results Fifty-two patients of Middle Eastern (primarily Egyptian) descent were included in the study. Thirty-two patients were treated with ledipasvir/sofosbuvir (Harvoni®) ± ribavirin, 12 patients were treated with ombitasvir/paritaprevir/ritonavir/dasabuvir (ViekiraPak®) ± ribavirin, and eight patients were treated with sofosbuvir/Velpatasvir (Epclusa®). Ten patients (19.2%) had compensated cirrhosis. Overall, SVR at 12 weeks was achieved in 94% in patients who received one of the three DAA regimens (93.8% in Harvoni® group, 91.7 % in ViekiraPak® group and 100% in Epclusa® group). Prior treatment status and type of regimen used in the presence of compensated cirrhosis had no statistical significance on overall SVR achievement (P value = 0.442 and P value = 0.091, respectively). The most common adverse effect was fatigue (27%). Conclusions In the real-world setting, DAAs are effective and well tolerated in patients with chronic HCV GT-4 infection with a high overall SVR rate of 94%. Large-scale studies are needed to further assess this SVR in these groups. PMID:29707080

Cost-Effectiveness of Direct-Acting Anti-viral Treatment in Hepatitis C-infected Liver Transplant Candidates with Compensated Cirrhosis and Hepatocellular Carcinoma

PubMed Central

Salazar, James; Saxena, Varun; Kahn, James G.; Roberts, John P.; Mehta, Neil; Volk, Michael; Lai, Jennifer C.

2016-01-01

Background HCV(+) donors represent an effective strategy to increase liver donor availability to HCV-infected recipients. However, many HCV(+) transplant candidates are now receiving treatment with direct acting anti-virals (DAA) that lower the risk of posttransplant HCV recurrence but could make the patient ineligible for HCV(+) livers. Methods We compared pretransplant DAA treatment versus deferred DAA treatment using a cost-effectiveness decision analysis model to estimate incremental cost-effectiveness ratios (ICERs; cost per quality-adjusted life year [QALY] gained) from the societal perspective across a range of HCV(+) liver availability rates. For practical considerations, the population modelled was restricted to well-compensated HCV(+) cirrhotics listed for liver transplantation with HCC MELD exception points. Results Under base case conditions, the deferred DAA treatment strategy was found to be the “dominant” strategy. That is, it provided superior health outcomes at cost savings compared to the pretransplant DAA treatment strategy. The pretransplant DAA treatment strategy trended towards cost-effectiveness as HCV(+) donor liver availability declined. However, only in 1 scenario that was highly optimized for favorable outcomes in the pretransplant DAA treatment arm (low availability of HCV(+) organs, low cost of DAA treatment, high cost of HCV recurrence) was the ICER associated with HCV DAA treatment before transplant <$150,000/QALY gained. Conclusions Deferring HCV treatment until after liver transplant and maintaining access to the expanded pool of HCV(+) donors appears to be the most cost-effective strategy for well-compensated HCV-infected cirrhotics listed for liver transplantation with HCC, even in geographic areas of relatively low HCV(+) donor availability. PMID:27926593

Examining Hepatitis, A and B Vaccination, and HBV Reactivation Monitoring During Direct-Acting Antiviral Therapy for Hepatitis C.

PubMed

Davison, John; O'Shea, Amy; Waterbury, Nancee; Villalvazo, Yolanda

2018-05-30

The objective of this study was to examine Hepatitis A (HAV) and Hepatitis B (HBV) screening, and the risk of HBV reactivation during Hepatitis C (HCV) therapy with direct-acting antivirals (DAAs). A retrospective chart review was performed of patients treated with second generation DAA therapy from January 2014 to September 2016 at the Iowa City VA Healthcare System. In total 409 patients initiated HCV treatment, 308 (75%) and 241 (59%) were HAV and HBV vaccine eligible, respectively. Among those, 24 (8%) received a HAV vaccine, while only 20 (8%) received a HBV vaccine. Of these, 7 patients initiating an immunization in the clinic had record of completing the series. Further, 101 patients had a reactive Hepatitis B core Antibody indicating previous HBV infection, and 3 of these were tested for HBV reactivation during HCV therapy. Overall, the assessment found low rates of HAV and HBV vaccine administration, indicating missed opportunities for preventative care during HCV therapy. With the known risk of HBV reactivation with DAAs, the need for HAV and HBV screening is essential.

Anti-E1E2 antibodies status prior therapy favors direct-acting antiviral treatment efficacy.

PubMed

Virlogeux, Victor; Berthillon, Pascale; Bordes, Isabelle; Larrat, Sylvie; Crouy, Stéphanie; Scholtès, Caroline; Pradat, Pierre; Maynard, Marianne; Zoulim, Fabien; Leroy, Vincent; Chemin, Isabelle; Trépo, Christian; Petit, Marie-Anne

2018-03-15

Presence of anti-E1E2 antibodies was previously associated with spontaneous cure of hepatitis C virus (HCV) and predictive before treatment of a sustained virological response (SVR) to bi- or tri-therapy in naïve or experienced patients, regardless of HCV genotype. We investigated the impact of anti-E1E2 seroprevalence at baseline on treatment response in patients receiving direct-acting antiviral (DAA) therapy. We screened anti-E1E2 antibodies by ELISA in serum samples collected at treatment initiation for two groups of patients: 59 with SVR at the end of DAA treatment and 44 relapsers after DAA treatment. Nineteen patients received a combination of ribavirin (RBV) or PEG-interferon/ribavirin with sofosbuvir or daclatasvir and others received interferon-free treatment with DAA±RBV. HCV viral load was measured at different time points during treatment in a subgroup of patients. A significant association was observed between presence of anti-E1E2 and HCV viral load<6log10 prior treatment. Among patients with anti-E1E2 at baseline, 70% achieved SVR whereas among patients without anti-E1E2, only 45% achieved SVR. Conversely, 66% of patients experiencing DAA-failure were anti-E1E2 negative at baseline. In the multivariate analysis, presence of anti-E1E2 was significantly associated with SVR after adjustment on potential cofounders such as age, sex, fibrosis stage, prior HCV treatment and alanine aminotransferase (ALT) level. The presence of anti-E1E2 at treatment initiation is a predictive factor of SVR among patients treated with DAA and more likely among patients with low initial HCV viral load (<6log10). Absence of anti-E1E2 at baseline could predict DAA-treatment failure. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Cost-Effectiveness of Direct-Acting Antiviral Treatment in Hepatitis C-Infected Liver Transplant Candidates With Compensated Cirrhosis and Hepatocellular Carcinoma.

PubMed

Salazar, James; Saxena, Varun; Kahn, James G; Roberts, John P; Mehta, Neil; Volk, Michael; Lai, Jennifer C

2017-05-01

Hepatitis C virus (HCV)(+) donors represent an effective strategy to increase liver donor availability to HCV-infected recipients. However, many HCV(+) transplant candidates are now receiving treatment with direct-acting anti-viral (DAA) agents that lower the risk of posttransplant HCV recurrence but could make the patient ineligible for HCV(+) livers. We compared pretransplant DAA treatment versus deferred DAA treatment using a cost-effectiveness decision analysis model to estimate incremental cost-effectiveness ratios (cost per quality-adjusted life year gained) from the societal perspective across a range of HCV(+) liver availability rates. For practical considerations, the population modeled was restricted to well-compensated HCV(+) cirrhotics listed for liver transplantation with hepatocellular carcinoma MELD exception points. Under base case conditions, the deferred DAA treatment strategy was found to be the "dominant" strategy. That is, it provided superior health outcomes at cost savings compared to the pretransplant DAA treatment strategy. The pretransplant DAA treatment strategy trended towards cost-effectiveness as HCV(+) donor liver availability declined. However, only in 1 scenario that was highly optimized for favorable outcomes in the pretransplant DAA treatment arm (low availability of HCV(+) organs, low cost of DAA treatment, high cost of HCV recurrence) was the incremental cost-effectiveness ratio associated with HCV DAA treatment before transplant less than US $150 000/quality-adjusted life-year gained. Deferring HCV treatment until after liver transplant and maintaining access to the expanded pool of HCV(+) donors appears to be the most cost-effective strategy for well-compensated HCV-infected cirrhotics listed for liver transplantation with hepatocellular carcinoma, even in geographic areas of relatively low HCV(+) donor availability.

78 FR 63218 - Draft Guidance for Industry on Chronic Hepatitis C Virus Infection: Developing Direct-Acting...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-23

...] Draft Guidance for Industry on Chronic Hepatitis C Virus Infection: Developing Direct-Acting Antiviral... entitled ``Chronic Hepatitis C Virus Infection: Developing Direct-Acting Antiviral Drugs for Treatment... antiviral (DAA) drugs for the treatment of chronic hepatitis C. This guidance revises and replaces a...

Newly diagnosed hepatocellular carcinoma in patients with advanced hepatitis C treated with DAAs: A prospective population study.

PubMed

Romano, Antonietta; Angeli, Paolo; Piovesan, Sara; Noventa, Franco; Anastassopoulos, Georgios; Chemello, Liliana; Cavalletto, Luisa; Gambato, Martina; Russo, Francesco Paolo; Burra, Patrizia; Vincenzi, Valter; Scotton, Pier Giorgio; Panese, Sandro; Tempesta, Diego; Bertin, Tosca; Carrara, Maurizio; Carlotto, Antonio; Capra, Franco; Carolo, Giada; Scroccaro, Giovanna; Alberti, Alfredo

2018-03-16

Direct-acting antiviral agents (DAAs) are safe and effective in patients with hepatitis C. Conflicting data were reported on the risk of hepatocellular carcinoma (HCC) during/after therapy with DAAs. The aim of this study was to evaluate the incidence of newly diagnosed HCC and associated risk factors in patients with advanced hepatitis C treated with DAAs. The study is based on the NAVIGATORE platform, a prospectively recording database of all patients with hepatitis C receiving DAAs in the Veneto region of Italy. The inclusion criteria were: fibrosis stage ≥F3. The exclusion criteria were: Child-Turcotte-Pugh (CTP)-C, liver transplantation before DAAs, history or presence of HCC, follow-up <4 weeks after starting DAAs. A total of 3,917 out of 4,234 consecutive patients were included, with a mean follow-up of 536.2 ± 197.6 days. Overall, HCC was diagnosed in 55 patients. During the first year, HCC incidence was 0.46% (95% CI 0.12-1.17) in F3, 1.49% (1.03-2.08) in CTP-A and 3.61% (1.86-6.31) in CTP-B cirrhotics; in the second year, HCC incidences were 0%, 0.2%, and 0.69%, respectively. By multivariate analysis, HCC was significantly associated with an aspartate aminotransferase to platelet ratio ≥2.5 (hazard ratio [HR] 2.03; 95% CI 1.14-3.61; p = 0.016) and hepatitis B virus infection (HR 3.99; 1.24-12.91; p = 0.021). Failure to achieve a sustained virological response was strongly associated with development of HCC (HR 9.09; 5.2-16.1; p = 0.0001). A total of 29% of patients with HCC had an aggressive tumor, often seen in the early phase of treatment. These data, obtained in a large, prospective, population-based study, indicate that in patients with advanced hepatitis C receiving DAAs, the risk of "de novo" hepatocarcinoma during the first year is not higher, and might be lower, than that of untreated patients. The risk further declines thereafter. Early hepatocarcinoma appearance may reflect pre-existing, microscopic, undetectable tumors

Limiting the access to direct-acting antivirals against HCV: an ethical dilemma.

PubMed

Gentile, Ivan; Maraolo, Alberto E; Niola, Massimo; Graziano, Vincenzo; Borgia, Guglielmo; Paternoster, Mariano

2016-11-01

Hepatitis C virus (HCV) infection affects about 200 million people worldwide and represents a leading cause of liver-related mortality. Eradication of HCV infection, achieved mainly through direct-acting antivirals (DAA), results in a decrease of mortality and an improvement of quality of life. These drugs have a maximal efficacy and an optimal tolerability. However, their high cost precludes a universal access even in wealthy countries. Areas covered: This article deals with the policies adopted for the use of the new anti-HCV drugs, especially in Europe and most of all in Italy, supposedly the developed country with the highest HCV prevalence. The literature search was performed using Pubmed and Web of Science. Moreover, national regulatory institutional websites were consulted. Expert commentary: The current policy of limitation to the access of the DAA presents a series of ethical issues that makes it non-applicable. A 'treat-all' strategy should resolve all ethical dilemmas, by virtue of the wide benefits of anti-HCV treatment not only for the advanced stage of infection, but also for the initial stages. A reduction in price of the drugs is the actual condition to achieve such a change.

Hepatitis C virus eradication by direct-acting antiviral agents improves carotid atherosclerosis in patients with severe liver fibrosis.

PubMed

Petta, Salvatore; Adinolfi, Luigi Elio; Fracanzani, Anna Ludovica; Rini, Francesca; Caldarella, Rosalia; Calvaruso, Vincenza; Cammà, Calogero; Ciaccio, Marcello; Di Marco, Vito; Grimaudo, Stefania; Licata, Anna; Marrone, Aldo; Nevola, Riccardo; Pipitone, Rosaria Maria; Pinto, Antonio; Rinaldi, Luca; Torres, Daniele; Tuttolomondo, Antonino; Valenti, Luca; Fargion, Silvia; Craxì, Antonio

2018-07-01

Recent studies suggest an association between hepatitis C virus (HCV) infection and cardiovascular damage, including carotid atherosclerosis, with a possible effect of HCV clearance on cardiovascular outcomes. We aimed to examine whether HCV eradication by direct-acting antiviral agents (DAA) improves carotid atherosclerosis in HCV-infected patients with advanced fibrosis/compensated cirrhosis. One hundred eighty-two consecutive patients with HCV and advanced fibrosis or compensated cirrhosis were evaluated. All patients underwent DAA-based antiviral therapy according to AISF/EASL guidelines. Intima-media thickness (IMT), carotid thickening (IMT ≥1 mm) and carotid plaques, defined as focal thickening of ≥1.5 mm at the level of the common carotid, were evaluated by ultrasonography (US) at baseline and 9-12 months after the end of therapy. Fifty-six percent of patients were male, mean age 63.1 ± 10.4 years, and 65.9% had compensated cirrhosis. One in five had diabetes, 14.3% were obese, 41.8% had arterial hypertension and 35.2% were smokers. At baseline, mean IMT was 0.94 ± 0.29 mm, 42.8% had IMT ≥1 mm, and 42.8% had carotid plaques. All patients achieved a 12-week sustained virological response. IMT significantly decreased from baseline to follow-up (0.94 ± 0.29 mm vs. 0.81 ± 0.27, p <0.001). Consistently, a significant reduction in the prevalence of patients with carotid thickening from baseline to follow-up was observed (42.8% vs. 17%, p <0.001), while no changes were reported for carotid plaques (42.8% vs. 47.8%, p = 0.34). These results were confirmed in subgroups of patients stratified for cardiovascular risk factors and liver disease severity. HCV eradication by DAA improves carotid atherosclerosis in patients with severe fibrosis with or without additional metabolic risk factors. The impact of this improvement in the atherosclerotic burden in terms of reduction of major cardiovascular outcomes is worth

Mathematical Modeling of Hepatitis C Prevalence Reduction with Antiviral Treatment Scale-Up in Persons Who Inject Drugs in Metropolitan Chicago

DOE PAGES

Echevarria, Desarae; Gutfraind, Alexander; Boodram, Basmattee; ...

2015-08-21

New direct-acting antivirals (DAAs) provide an opportunity to combat hepatitis C virus (HCV) infection in persons who inject drugs (PWID). In our paper, we use a mathematical model to predict the impact of a DAA-treatment scale-up on HCV prevalence among PWID and the estimated cost in metropolitan Chicago.

Mathematical Modeling of Hepatitis C Prevalence Reduction with Antiviral Treatment Scale-Up in Persons Who Inject Drugs in Metropolitan Chicago

DOE Office of Scientific and Technical Information (OSTI.GOV)

Echevarria, Desarae; Gutfraind, Alexander; Boodram, Basmattee

New direct-acting antivirals (DAAs) provide an opportunity to combat hepatitis C virus (HCV) infection in persons who inject drugs (PWID). In our paper, we use a mathematical model to predict the impact of a DAA-treatment scale-up on HCV prevalence among PWID and the estimated cost in metropolitan Chicago.

75 FR 55797 - Draft Guidance for Industry on Chronic Hepatitis C Virus Infection: Developing Direct-Acting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-14

...] Draft Guidance for Industry on Chronic Hepatitis C Virus Infection: Developing Direct-Acting Antiviral... entitled ``Chronic Hepatitis C Virus Infection: Developing Direct-Acting Antiviral Agents for Treatment... antiviral agents (DAAs), defined as agents that interfere with specific steps in the hepatitis C virus (HCV...

Hepatocellular carcinoma decreases the chance of successful hepatitis C virus therapy with direct-acting antivirals.

PubMed

Prenner, Stacey B; VanWagner, Lisa B; Flamm, Steven L; Salem, Riad; Lewandowski, Robert J; Kulik, Laura

2017-06-01

The approval of all-oral direct-acting antiviral (DAA) regimens for the treatment of hepatitis C virus (HCV) has led to the expansion of therapy to include patients with cirrhosis who have hepatocellular carcinoma (HCC). Data on the use of DAAs in HCV+ patients with HCC is limited. The aim of this study was to assess the efficacy of all-oral-DAA regimens in HCV+ cirrhotic patients who have or had HCC compared to those without HCC. A retrospective cohort study was conducted on all cirrhotic patients who were treated for HCV with DAAs at our institution between January 2014 and November 2015. A total of 421 HCV+ patients with cirrhosis were identified, of whom 33% had active or a history of HCC. Failure to achieve sustained virologic response (SVR) occurred in 21% of patients with HCC compared to 12% of patients without HCC (p=0.009). Of the 29 patients with HCC who did not achieve SVR, 27 (93%) occurred when an active tumor was present. DAA therapy in the presence of an inactive tumor or after removal of tumor (resection/transplant) resulted in excellent SVR rates, similar to those without HCC (p<0.0001). In multivariable analysis, the primary predictor of DAA treatment failure was the presence of active HCC at the time of HCV treatment initiation (adjusted odds ratio=8.5, 95% confidence interval=3.90-18.49). The presence of active HCC tumor at the initiation of HCV therapy is significantly associated with all-oral DAA treatment failure. HCV treatment after curative therapies for HCC resulted in excellent SVR. The new medications for hepatitis C have excellent cure rates. However, our study shows that in patients with both liver cancer and hepatitis C, they do not achieve these cure rates. Patients with liver cancer are almost 8 times more likely to fail hepatitis C treatment than patients without liver cancer. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Minimum target prices for production of direct-acting antivirals and associated diagnostics to combat hepatitis C virus

PubMed Central

van de Ven, Nikolien; Fortunak, Joe; Simmons, Bryony; Ford, Nathan; Cooke, Graham S; Khoo, Saye; Hill, Andrew

2015-01-01

Combinations of direct-acting antivirals (DAAs) can cure hepatitis C virus (HCV) in the majority of treatment-naïve patients. Mass treatment programs to cure HCV in developing countries are only feasible if the costs of treatment and laboratory diagnostics are very low. This analysis aimed to estimate minimum costs of DAA treatment and associated diagnostic monitoring. Clinical trials of HCV DAAs were reviewed to identify combinations with consistently high rates of sustained virological response across hepatitis C genotypes. For each DAA, molecular structures, doses, treatment duration, and components of retrosynthesis were used to estimate costs of large-scale, generic production. Manufacturing costs per gram of DAA were based upon treating at least 5 million patients per year and a 40% margin for formulation. Costs of diagnostic support were estimated based on published minimum prices of genotyping, HCV antigen tests plus full blood count/clinical chemistry tests. Predicted minimum costs for 12-week courses of combination DAAs with the most consistent efficacy results were: US$122 per person for sofosbuvir+daclatasvir; US$152 for sofosbuvir+ribavirin; US$192 for sofosbuvir+ledipasvir; and US$115 for MK-8742+MK-5172. Diagnostic testing costs were estimated at US$90 for genotyping US$34 for two HCV antigen tests and US$22 for two full blood count/clinical chemistry tests. Conclusions: Minimum costs of treatment and diagnostics to cure hepatitis C virus infection were estimated at US$171-360 per person without genotyping or US$261-450 per person with genotyping. These cost estimates assume that existing large-scale treatment programs can be established. (Hepatology 2015;61:1174–1182) PMID:25482139

Cost-effectiveness of the highly effective direct-acting antivirals in the treatment of chronic hepatitis C in Hong Kong.

PubMed

Lo, Angeline Oi-Shan; Chan, Henry Lik-Yuen; Wong, Vincent Wai-Sun; Wong, Grace Lai-Hung

2017-05-01

In Asia-Pacific where cost is a major concern, peginterferon plus ribavirin (PR) often remain as the standard of care in chronic hepatitis C (CHC) treatment, while the direct-acting antivirals (DAAs) are commonly recommended as retreatment. Newer DAAs can achieve a sustained virological response (SVR) of nearly 100% with pan-genotypic coverage, that is "Highly Effective DAAs." We aimed to investigate the most desirable cost range for the Highly Effective DAAs using Hong Kong as an example. Markov modeling was performed using PR as the reference strategy. The cost-effectiveness of the Highly Effective DAAs was compared with sofosbuvir-PR (first-line and rescue) and boceprevir-PR therapies. A 50-year-old genotype 1b hepatitis C virus (HCV) infected treatment-naïve patient with METAVIR F3 was used as the base case scenario to reflect the commonest HCV genotype in Hong Kong. The use of PR would incur a lifetime cost of US$35,854 and effectiveness of 14.85 quality-adjusted life-year (QALY). Sofosbuvir-PR as first-line treatment was dominated by other regimes. If Sofosbuvir-PR rescue therapy was used, the drug cost of Highly Effective DAAs should be set below US$43,553, with a cost-effectiveness ratio (CER) of US$3035/QALY compared with PR. In regions where Boceprevir-PR was still used as first-line therapy, the desirable drug cost of Highly Effective DAAs would be below US$56,985 to achieve a CER of US$5427/QALY. The most desirable costs of the Highly Effective DAAs would be below US$43,553 if Sofosbuvir-PR rescue therapy is used and below US$56,985 if Boceprevir-PR therapy is used. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Direct-acting Antiviral Agents for the Treatment of Chronic Hepatitis C Virus Infection

PubMed Central

Nakamoto, Shingo; Nakamura, Masato; Jiang, Xia; Miyamura, Tatsuo; Wu, Shuang; Yokosuka, Osamu

2014-01-01

Hepatitis C virus (HCV) is a leading cause of cirrhosis and hepatocellular carcinoma (HCC) in the US and Japan. Therefore, eradication of HCV may reduce the occurrence of HCC in HCV-infected individuals. In 2011, the use of first-generation HCV NS3/4A protease inhibitors such as telaprevir and boceprevir was initiated for clinical treatment of HCV. Administration of telaprevir and boceprevir plus peginterferon and ribavirin increased rates of sustained virological response (SVR) in HCV genotype 1-infected patients. However, this treatment regimen also led to severe adverse events. Second-generation direct-acting antiviral agents (DAAs) for HCV, such as simeprevir plus peg-interferon and ribavirin also resulted in higher SVR rates, with similar adverse events to other peg-interferon and ribavirin treatments. Higher SVR rates in HCV genotype 1- and 2-infected patients were achieved with 12-16 weeks of sofosbuvir plus other class DAAs with/without ribavirin and 12 weeks of sofosbuvir plus ribavirin, respectively. For “difficult-to-treat” HCV-infected patients, more therapeutic options are needed. Further studies examining the efficacy and adverse effects of such therapies will be required for the development of additional treatments. PMID:26356295

Minimum target prices for production of direct-acting antivirals and associated diagnostics to combat hepatitis C virus.

PubMed

van de Ven, Nikolien; Fortunak, Joe; Simmons, Bryony; Ford, Nathan; Cooke, Graham S; Khoo, Saye; Hill, Andrew

2015-04-01

Combinations of direct-acting antivirals (DAAs) can cure hepatitis C virus (HCV) in the majority of treatment-naïve patients. Mass treatment programs to cure HCV in developing countries are only feasible if the costs of treatment and laboratory diagnostics are very low. This analysis aimed to estimate minimum costs of DAA treatment and associated diagnostic monitoring. Clinical trials of HCV DAAs were reviewed to identify combinations with consistently high rates of sustained virological response across hepatitis C genotypes. For each DAA, molecular structures, doses, treatment duration, and components of retrosynthesis were used to estimate costs of large-scale, generic production. Manufacturing costs per gram of DAA were based upon treating at least 5 million patients per year and a 40% margin for formulation. Costs of diagnostic support were estimated based on published minimum prices of genotyping, HCV antigen tests plus full blood count/clinical chemistry tests. Predicted minimum costs for 12-week courses of combination DAAs with the most consistent efficacy results were: US$122 per person for sofosbuvir+daclatasvir; US$152 for sofosbuvir+ribavirin; US$192 for sofosbuvir+ledipasvir; and US$115 for MK-8742+MK-5172. Diagnostic testing costs were estimated at US$90 for genotyping US$34 for two HCV antigen tests and US$22 for two full blood count/clinical chemistry tests. Minimum costs of treatment and diagnostics to cure hepatitis C virus infection were estimated at US$171-360 per person without genotyping or US$261-450 per person with genotyping. These cost estimates assume that existing large-scale treatment programs can be established. © 2014 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

Value and innovation of direct-acting antivirals: long-term health outcomes of the strategic plan for the management of hepatitis C in Spain.

PubMed

Turnes, Juan; Domínguez-Hernández, Raquel; Casado, Miguel Ángel

2017-12-01

To assess the long-term healthcare costs and health outcomes in association with the access to new direct-acting antivirals (DAAs), during the first year of the National Strategic Plan for Chronic Hepatitis C (SPCHC) in patients with chronic hepatitis C (CHC) in Spain. A decision tree and a lifetime Markov model were developed to simulate the natural history, morbidity, and mortality of a cohort of 51,900 patients with CHC before (pre-DAA strategy) and after (post-DAA strategy) access to DAAs, following SPCHC approval. The percentage of patients treated, transition probabilities, disease management costs, health state utility values, sustained virologic response rates and treatment costs were obtained from the literature and published data from Spain. The results were expressed in terms of costs (€, 2016), quality-adjusted life years (QALYs) and prevention of clinical events, with an annual discount rate of 3%. The post-DAA strategy would prevent 8,667 cases of decompensated cirrhosis, 5,471 cases of hepatocellular carcinoma, 1,137 liver transplants and 9,608 liver-related deaths. The cohort of 51,900 patients would require investments of 1,606 and 1,230 million euros with the post-DAA and pre-DAA strategies, respectively. This would produce 819,674 and 665,703 QALYs. The use of new DAA-based treatments in CHC patients during the first year after the implementation of the SPCHC significantly reduced long-term morbidity and mortality and increased quality of life; demonstrating that this plan is an efficient use of public health resources.

Hepatocellular carcinoma risk assessment by the measurement of liver stiffness variations in HCV cirrhotics treated with direct acting antivirals.

PubMed

Ravaioli, Federico; Conti, Fabio; Brillanti, Stefano; Andreone, Pietro; Mazzella, Giuseppe; Buonfiglioli, Federica; Serio, Ilaria; Verrucchi, Gabriella; Bacchi Reggiani, Maria Letizia; Colli, Agostino; Marasco, Giovanni; Colecchia, Antonio; Festi, Davide

2018-06-01

Direct-acting antivirals (DAA) are an effective treatment for hepatitis C virus infection. However, sustained virologic response (SVR) after DAA treatment does not seem to reduce the risk of hepatocellular carcinoma (HCC) development in these patients. Liver stiffness measurement (LSM) may predict the risk of developing HCC in liver cirrhosis patients. The aim of our study was to evaluate the role of LSM variation as predictor of HCC development in patients treated with DAA. In 139 HCV-related cirrhotic patients, LSM and laboratory tests were carried out at baseline (BL) and at the end of DAA treatment (EOT). Patients were followed for at least 6 months after the EOT. LSM reduction was expressed as Delta LS (∆LS). Cox regression analysis was used to identify prognostic factors for HCC development after DAA. Median LSM values were significantly reduced from BL to EOT (from 18.6 to 13.8 kPa; p < 0.001). The median ∆LS was -26.7% (IQR: -38.4% -13.6%). During a median follow-up of 15 months after DAA treatment, 20 (14.4%) patients developed HCC. Significant LSM reduction was observed both in patients who developed HCC and in those who did not, but this was significantly lower in the patients who developed HCC (-18.0% vs -28.9% p = 0.005). At multivariate analysis, ∆LS lower than -30%, Child-Turcotte-Pugh-B and history of HCC were independently associated with HCC development. Our results indicate that ∆LS is a useful non-invasive marker for predicting HCC development after DAA treatment. Copyright © 2018 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Impact of hepatitis C virus polymorphisms on direct-acting antiviral treatment efficacy: Regulatory analyses and perspectives.

PubMed

Harrington, Patrick R; Komatsu, Takashi E; Deming, Damon J; Donaldson, Eric F; O'Rear, Julian J; Naeger, Lisa K

2018-06-01

Several highly effective, interferon-free, direct-acting antiviral (DAA)-based regimens are available for the treatment of chronic hepatitis C virus (HCV) infection. Despite impressive efficacy overall, a small proportion of patients in registrational trials experienced treatment failure, which in some cases was associated with the detection of HCV resistance-associated substitutions (RASs) at baseline. In this article, we describe methods and key findings from independent regulatory analyses investigating the impact of baseline nonstructural (NS) 3 Q80K and NS5A RASs on the efficacy of current United States Food and Drug Administration (FDA)-approved regimens for patients with HCV genotype (GT) 1 or GT3 infection. These analyses focused on clinical trials that included patients who were previously naïve to the DAA class(es) in their investigational regimen and characterized the impact of baseline RASs that were enriched in the viral population as natural or transmitted polymorphisms (i.e., not drug-selected RASs). We used a consistent approach to optimize comparability of results across different DAA regimens and patient populations, including the use of a 15% sensitivity cutoff for next-generation sequencing results and standardized lists of NS5A RASs. These analyses confirmed that detection of NS3 Q80K or NS5A baseline RASs was associated with reduced treatment efficacy for multiple DAA regimens, but their impact was often minimized with the use of an intensified treatment regimen, such as a longer treatment duration and/or addition of ribavirin. We discuss the drug resistance-related considerations that contributed to pretreatment resistance testing and treatment recommendations in drug labeling for FDA-approved DAA regimens. Independent regulatory analyses confirmed that baseline HCV RASs can reduce the efficacy of certain DAA-based regimens in selected patient groups. However, highly effective treatment options are available for patients with or without

Antiviral therapy of hepatitis C in 2014: do we need resistance testing?

PubMed

Schneider, Maximilian David; Sarrazin, Christoph

2014-05-01

The treatment of chronic hepatitis C has fundamentally changed since the approval of the first direct-acting antivirals (DAA) in 2011. In addition to telaprevir and boceprevir, in 2014 two new NS3 protease inhibitors (simeprevir and faldaprevir), one non-nucleoside polymerase inhibitor (sofosbuvir) and one NS5a replication complex inhibitor (daclatasvir) have expanded the treatment options for chronic hepatitis C. Resistance-associated variants (RAV) are naturally produced during the HCV life cycle. The frequency of RAVs within HCV quasispecies mainly depends on their replicational fitness. Variants conferring resistance to nucleos(t)ide analogues have not been detected, and the majority of NS3 protease-resistant variants are present at low frequencies (0.1-3%) before initiation of DAA-based therapies. However, the Q80K variant conferring resistance to simeprevir has been observed in 9-48% of untreated HCV genotype 1a-infected patients, leading to reduced SVR rates. Resistant variants are detectable in the majority of patients with treatment failure to NS3 protease inhibitor- or NS5a inhibitor-based antiviral therapy. Long-term follow-up studies by population-based sequence analysis have shown the disappearance of resistant variants in the majority of patients, with median times to loss of mutations of 4-64weeks. For the nucleotide analogue sofosbuvir, the emergence of the S282T resistant variant has been observed only in single patients, with reversion to wild-type within several weeks. Data are sparse on retreatment of patients with the same DAA or the same class of DAAs. However, retreatment with a different class of DAAs after failure of NS3 protease inhibitor-based therapy has been successful in small studies. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication." Copyright © 2014 Elsevier B.V. All rights reserved.

Increased recurrence rates of hepatocellular carcinoma after DAA therapy in a hepatitis C-infected Egyptian cohort: A comparative analysis.

PubMed

El Kassas, M; Funk, A L; Salaheldin, M; Shimakawa, Y; Eltabbakh, M; Jean, K; El Tahan, A; Sweedy, A T; Afify, S; Youssef, N F; Esmat, G; Fontanet, A

2018-06-01

In Egypt, hepatocellular carcinoma (HCC) is the most common form of cancer and direct-acting antivirals (DAA) are administered on a large scale to patients with chronic HCV infection to reduce the risk. In this unique setting, we aimed to determine the association of DAA exposure with early-phase HCC recurrence in patients with a history of HCV-related liver cancer. This was a prospective cohort study of an HCV-infected population from one Egyptian specialized HCC management centre starting from the time of successful HCC intervention. The incidence rates of HCC recurrence between DAA-exposed and nonexposed patients were compared, starting from date of HCC complete radiological response and censoring after 2 years. DAA exposure was treated as time varying. Two Poisson regressions models were used to control for potential differences in the exposed and nonexposed group; multivariable adjustment and balancing using inverse probability of treatment weighting (IPTW). We included 116 patients: 53 treated with DAAs and 63 not treated with DAAs. There was 37.7% and 25.4% recurrence in each group after a median of 16.0 and 23.0 months of follow-up, respectively. Poisson regression using IPTW demonstrated an association between DAAs and HCC recurrence with an incidence rate ratio of 3.83 (95% CI: 2.02-7.25), which was similar in the multivariable-adjusted model and various sensitivity analyses. These results add important evidence towards the possible role of DAAs in HCC recurrence and stress the need for further mechanistic studies and clinical trials to accurately confirm this role and to identify patient characteristics that may be associated with this event. © 2017 John Wiley & Sons Ltd.

Real-World Clinical Efficacy and Tolerability of Direct-Acting Antivirals in Hepatitis C Monoinfection Compared to Hepatitis C/HIV Coinfection in a Community Care Setting.

PubMed

Vijay, Gayam; Rajib, Hossain Muhammad; Mazin, Khalid; Sandipan, Chakaraborty; Osama, Mukhtar; Sumit, Dahal; Amrendra Kumar, Mandal; Arshpal, Gill; Pavani, Garlapati; Ramakrishnaiah, Sreedevi; Khalid, Mowyad; Jagannath, Sherigar; Mohammed, Mansour; Smruti, Mohanty

2018-06-22

Limited data exist comparing the safety and efficacy of direct-acting antivirals (DAAs) in hepatitis C virus (HCV) monoinfected and HCV/human immunodeficiency virus (HIV) coinfected patients in the real-world clinic practice setting. All HCV monoinfected and HCV/HIV coinfected patients treated with DAAs between January 2014 and October 2017 in community clinic settings were retrospectively analyzed. Pretreatment baseline patient characteristics, treatment efficacy, factors affecting sustained virologic response at 12 weeks (SVR 12) after treatment, and adverse reactions were compared between the groups. A total of 327 patients were included in the study, of which 253 were HCV monoinfected, and 74 were HCV/HIV coinfected. There was a statistically significant difference observed in SVR 12 when comparing HCV monoinfection and HCV/HIV coinfection (94% and 84%, respectively, p=0.005). However, there were no significant factors identified as a predictor of a reduced response. The most common adverse effect was fatigue (27%). No significant drug interaction was observed between DAA and antiretroviral therapy. None of the patients discontinued the treatment due to adverse events. In a real-world setting, DAA regimens have lower SVR 12 in HCV/HIV coinfection than in HCV monoinfection. Further studies involving a higher number of HCV/HIV coinfected patients are needed to identify real predictors of a reduced response.

A translational study of resistance emergence using sequential direct-acting antiviral agents for hepatitis C using ultra-deep sequencing.

PubMed

Abe, Hiromi; Hayes, C Nelson; Hiraga, Nobuhiko; Imamura, Michio; Tsuge, Masataka; Miki, Daiki; Takahashi, Shoichi; Ochi, Hidenori; Chayama, Kazuaki

2013-09-01

Direct-acting antiviral agents (DAAs) against hepatitis C virus (HCV) have recently been developed and are ultimately hoped to replace interferon-based therapy. However, DAA monotherapy results in rapid emergence of resistant strains and DAAs must be used in combinations that present a high genetic barrier to resistance, although viral kinetics of multidrug-resistant strains remain poorly characterized. The aim of this study is to track the emergence and fitness of resistance using combinations of telaprevir and NS5A or NS5B inhibitors with genotype 1b clones. HCV-infected chimeric mice were treated with DAAs, and resistance was monitored using direct and ultra-deep sequencing. Combination therapy with telaprevir and BMS-788329 (NS5A inhibitor) reduced serum HCV RNA to undetectable levels. The presence of an NS3-V36A telaprevir resistance mutation resulted in poor response to telaprevir monotherapy but showed significant HCV reduction when telaprevir was combined with BMS-788329. However, a BMS-788329-resistant strain emerged at low frequency. Infection with a BMS-788329-resistant NS5A-L31V mutation rapidly resulted in gain of an additional NS5A-Y93A mutation that conferred telaprevir resistance during combination therapy. Infection with dual NS5AL31V/NS5AY93H mutations resulted in poor response to combination therapy and development of telaprevir resistance. Although HCV RNA became undetectable soon after the beginning of combination therapy with BMS-788329 and BMS-821095 (NS5B inhibitor), rebound with emergence of resistance against all three drugs occurred. Triple resistance also occurred following infection with the NS3V36A/NS5AL31V/NS5AY93H triple mutation. Resistant strains easily develop from cloned virus strains. Sequential use of DAAs should be avoided to prevent emergence of multidrug-resistant strains.

Low incidence of hepatitis B virus reactivation and subsequent hepatitis in patients with chronic hepatitis C receiving direct-acting antiviral therapy.

PubMed

Tamori, A; Abiru, S; Enomoto, H; Kioka, K; Korenaga, M; Tani, J; Enomoto, M; Sugiyama, M; Masaki, T; Kawada, N; Yatsuhashi, H; Nishiguchi, S; Mizokami, M

2018-05-01

To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing interferon-free antihepatitis C virus (HCV) therapy, we examined HBV DNA in 25 HBV co-infected patients and 765 patients with resolved HBV infection during and after treatment with direct-acting antiviral agents (DAAs). Among those with HCV genotype 1, asunaprevir plus daclatasvir was administered to 160 patients, sofosbuvir (SOF) plus ledipasvir to 438 patients and paritaprevir plus ombitasvir and ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus ribavirin. Three patients with an HBV DNA level ≥2000 IU/mL were treated with entecavir before anti-HCV therapy, without reactivation of HBV. In 3 of 22 (12%) HBV surface antigen (HBsAg)-positive patients with an HBV DNA level <2000 IU/mL, the viral load increased during treatment. However, hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV DNA level spontaneously decreased after DAA therapy. We compared anti-HBs titres at baseline with those at post-DAA therapy in 123 patients without HBsAg. There was no significant difference in anti-HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in HBsAg-negative patients treated with DAA therapy. Additionally, hepatitis did not occur in HBV-reactivated patients with a baseline HBV DNA level <2000 IU/mL before DAA therapy. © 2017 John Wiley & Sons Ltd.

Efficacy and Safety of Direct Acting Antivirals in Kidney Transplant Recipients with Chronic Hepatitis C Virus Infection.

PubMed

Lin, Ming V; Sise, Meghan E; Pavlakis, Martha; Amundsen, Beth M; Chute, Donald; Rutherford, Anna E; Chung, Raymond T; Curry, Michael P; Hanifi, Jasmine M; Gabardi, Steve; Chandraker, Anil; Heher, Eliot C; Elias, Nahel; Riella, Leonardo V

2016-01-01

The prevalence of Hepatitis C Virus (HCV) infection is significantly higher in patients with end-stage renal disease compared to the general population and poses important clinical challenges in patients who undergo kidney transplantation. Historically, interferon-based treatment options have been limited by low rates of efficacy and significant side effects, including risk of precipitating rejection. Limited data exist on the use of all-oral, interferon-free direct-acting antiviral (DAA) therapies in kidney transplant recipients. In this study, we performed a retrospective chart review with prospective clinical follow-up of post-kidney transplant patients treated with DAA therapies at three major hospitals in Boston, MA. A total of 24 kidney recipients with HCV infection received all-oral DAA therapy post-transplant. Patients were predominantly male (79%) with a median age of 60 years (range 34-70 years), median creatinine of 1.2 mg/dL (0.66-1.76), and 42% had advanced fibrosis or cirrhosis. The majority had HCV genotype 1a infection (58%). All patients received full-dose sofosbuvir; it was paired with simeprevir (9 patients without and 3 patients with ribavirin), ledipasvir (7 patients without and 1 patient with ribavirin) or ribavirin alone (4 patients). The overall sustained virologic response (SVR12) was 91% (21 out of 23 patients). One patient achieved SVR4 but demised prior to SVR12 check point due to treatment unrelated cause. Two treatment failures were successfully retreated with alternative DAA regimens and achieved SVR. Both initials failures occurred in patients with advanced fibrosis or cirrhosis, with genotype 1a infection, and prior HCV treatment failure. Adverse events were reported in 11 patients (46%) and were managed clinically without discontinuation of therapy. Calcineurin inhibitor trough levels did not significantly change during therapy. In this multi-center series of patients, all-oral DAA therapy appears to be safe and effective in post

Efficacy and Safety of Direct Acting Antivirals in Kidney Transplant Recipients with Chronic Hepatitis C Virus Infection

PubMed Central

Lin, Ming V.; Sise, Meghan E.; Pavlakis, Martha; Amundsen, Beth M.; Chute, Donald; Rutherford, Anna E.; Chung, Raymond T.; Curry, Michael P.; Hanifi, Jasmine M.; Gabardi, Steve; Chandraker, Anil; Heher, Eliot C.; Elias, Nahel; Riella, Leonardo V.

2016-01-01

The prevalence of Hepatitis C Virus (HCV) infection is significantly higher in patients with end-stage renal disease compared to the general population and poses important clinical challenges in patients who undergo kidney transplantation. Historically, interferon-based treatment options have been limited by low rates of efficacy and significant side effects, including risk of precipitating rejection. Limited data exist on the use of all-oral, interferon-free direct-acting antiviral (DAA) therapies in kidney transplant recipients. In this study, we performed a retrospective chart review with prospective clinical follow-up of post-kidney transplant patients treated with DAA therapies at three major hospitals in Boston, MA. A total of 24 kidney recipients with HCV infection received all-oral DAA therapy post-transplant. Patients were predominantly male (79%) with a median age of 60 years (range 34–70 years), median creatinine of 1.2 mg/dL (0.66–1.76), and 42% had advanced fibrosis or cirrhosis. The majority had HCV genotype 1a infection (58%). All patients received full-dose sofosbuvir; it was paired with simeprevir (9 patients without and 3 patients with ribavirin), ledipasvir (7 patients without and 1 patient with ribavirin) or ribavirin alone (4 patients). The overall sustained virologic response (SVR12) was 91% (21 out of 23 patients). One patient achieved SVR4 but demised prior to SVR12 check point due to treatment unrelated cause. Two treatment failures were successfully retreated with alternative DAA regimens and achieved SVR. Both initials failures occurred in patients with advanced fibrosis or cirrhosis, with genotype 1a infection, and prior HCV treatment failure. Adverse events were reported in 11 patients (46%) and were managed clinically without discontinuation of therapy. Calcineurin inhibitor trough levels did not significantly change during therapy. In this multi-center series of patients, all-oral DAA therapy appears to be safe and effective in

Increased incidence of liver cancer after successful DAA treatment of chronic hepatitis C: Fact or fiction?

PubMed

Alberti, Alfredo; Piovesan, Sara

2017-06-01

Therapy of hepatitis C has been revolutionized by Direct Antiviral Agents. These drugs are safe and efficacious in all infected patients, including those with advanced, or decompensated cirrhosis, and are currently largely used in such cases in clinical practice worldwide. It was therefore cause of great concern the publication of two reports suggesting that treatment with DAAs could increase the risk of hepatocellular carcinoma in cirrhotic patients, particularly in those receiving antiviral therapy after having been cured for an HCC. These reports have generated a great and controversial debate and have been followed by a series of other publications not confirming such increased risk. This article summarizes published studies assessing the relation between DAA therapy and HCC in two different clinical setting: HCC recurrence in patients with an history of cured HCC and "de novo" HCC occurrence in patients without previous HCC. Rates of HCC recurrence after DAAs were extremely variable in different studies, reflecting great heterogeneity of this clinical setting. Data on "de novo" HCC incidence were more homogeneous and suggest that treatment with DAAs is not modifying the risk of developing HCC in the first 6-12 months. The possibility that treatment with DAAs may favour tumour growth and spread in individual patients with active HCC foci is suggested by some observations but remains unproven. There is clearly a need for prospective studies designed to better define these issues. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

HCV clearance after direct-acting antivirals in patients with cirrhosis by stages of liver impairment: The ITAL-C network study.

PubMed

Ippolito, Antonio Massimo; Milella, Michele; Messina, Vincenzo; Conti, Fabio; Cozzolongo, Raffaele; Morisco, Filomena; Brancaccio, Giuseppina; Barone, Michele; Santantonio, Teresa; Masetti, Chiara; Tundo, Paolo; Smedile, Antonina; Carretta, Vito; Gatti, Pietro; Termite, Antonio Patrizio; Valvano, Maria Rosa; Bruno, Giuseppe; Fabrizio, Claudia; Andreone, Pietro; Zappimbulso, Marianna; Gaeta, Giovanni Battista; Napoli, Nicola; Fontanella, Luca; Lauletta, Gianfranco; Cuccorese, Giuseppe; Metrangolo, Antonio; Francavilla, Ruggiero; Ciracì, Emanuela; Rizzo, Salvatore; Andriulli, Angelo

2017-09-01

Sustained virological response (SVR12) rates at 12 weeks after treatment for HCV-infected patients with decompensated cirrhosis are used when referring to those with moderate functional impairment, while few data are available for those with more severe impairment. The use of the cirrhosis staging system proposed by D'Amico might provide new insights on timing for antiviral therapy. We investigated efficacy (SVR12), safety, and post-treatment variations in clinical and laboratory parameters in 2612 patients with advanced fibrosis (n=575) or cirrhosis (n=2037). Cirrhosis was in the compensated phase (without/with varices) or had previously been in the decompensated stage. Different direct-acting antiviral (DAA) regimens were administered in accordance with scientific guidelines. The SVR12 rate was 97.6% in patients with advanced fibrosis. For patients with cirrhosis, the rate was 96.5% in stage 1, 95.1% in stage 2, 100% in stage 3, 95.7% in stage 4, and 93.6% in stage 5. These rates were independent of gender, age, HCV genotype, and treatment schedule. Positive changes in biochemical parameters and CPT classes following therapy were evident in compensated and previously decompensated patients. Our findings support the use of DAAs in patients with advanced cirrhosis (stages 3-5) who are at greatest risk and have the most to gain from therapy. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Liver stiffness predicts the response to direct-acting antiviral-based therapy against chronic hepatitis C in cirrhotic patients.

PubMed

Neukam, K; Morano-Amado, L E; Rivero-Juárez, A; Macías, J; Granados, R; Romero-Palacios, A; Márquez, M; Merino, D; Ortega, E; Alados-Arboledas, J C; Cucurull, J; Omar, M; Ryan-Murua, P; Pineda, J A

2017-05-01

The purpose of this investigation was to evaluate the impact of liver stiffness (LS) on the response to direct-acting antiviral (DAA)-based therapy against hepatitis C virus (HCV) infection in cirrhotic patients. Those patients included in two Spanish prospective cohorts of patients receiving therapy based on at least one DAA, who showed a baseline LS ≥ 12.5 kPa and who had reached the scheduled time point for sustained virological response evaluation 12 weeks after completing therapy (SVR12) were analysed. Pegylated interferon/ribavirin-based therapy plus an HCV NS3/4A protease inhibitor (PR-PI group) was administered to 198 subjects, while 146 received interferon-free regimens (IFN-free group). The numbers of patients with SVR12 according to an LS < 21 kPa versus ≥21 kPa were 59/99 (59.6%) versus 46/99 (46.5%) in the PR-PI group (p = 0.064) and 41/43 (95.3%) versus 90/103 (87.4%) in the IFN-free group (p = 0.232). Corresponding figures for the relapse rates in those who presented end-of-treatment response (ETR) were 3/62 (4.8%) versus 10/56 (17.9%, p = 0.024) and 1/42 (2.4%) versus 8/98 (8.2%, p = 0.278), respectively. In a multivariate analysis adjusted for age, sex and use of interferon, a baseline LS ≥ 21 kPa was identified as an independent predictor of relapse [adjusted odds ratio, AOR (95% confidence interval, CI): 4.228 (1.344-13.306); p = 0.014] in those patients with ETR. LS above 21 kPa is associated with higher rates of relapse to DAA-based therapy in HCV-infected patients with cirrhosis in clinical practice. LS could help us to tailor the duration and composition of DAA-based combinations in cirrhotic subjects, in order to minimise the likelihood of relapse.

Direct-Acting Antiviral Therapy for Chronic HCV Infection Results in Liver Stiffness Regression Over 12 Months Post-treatment.

PubMed

Chan, Justin; Gogela, Neliswa; Zheng, Hui; Lammert, Sara; Ajayi, Tokunbo; Fricker, Zachary; Kim, Arthur Y; Robbins, Gregory K; Chung, Raymond T

2018-02-01

Liver fibrosis stage determines risk of morbidity and mortality from chronic hepatitis C virus (HCV) infection. Prior data have shown long-term reversal of liver fibrosis, measured by vibration-controlled transient elastography (VCTE), in patients successfully treated with interferon-based therapies. Our study sought to determine the effect of treatment with modern HCV direct-acting antiviral (DAA) therapy on noninvasive liver fibrosis measurements. A total of 70 patients had VCTE-based liver stiffness measurement (LSM) taken before treatment, directly after treatment completion, and at least 12 months after completion of DAA therapy. Our primary outcome was a >30% improvement in VCTE score at the end of follow-up, relative to baseline. The sustained virologic response rate in our cohort was 95.7%. In our cohort, 34 (48.6%) met the primary outcome. Those who had baseline elevated alanine aminotransferase (OR 3.27; 95% CI 1.13-9.47) and genotype 1 (OR 14.63; 95% CI 1.70-125.83) had higher odds of meeting that outcome, and this remained significant after adjusting for age, baseline body mass index, gender, baseline elevated alkaline phosphatase levels, treatment experience, liver transplant status, smoking, and baseline liver stiffness. Treatment of chronic HCV with modern DAA therapy was associated with a significant improvement in LSM by VCTE measurement, suggesting possible early improvement in liver fibrosis along with resolution of inflammation over the first year after treatment completion.

Shift in disparities in hepatitis C treatment from interferon to DAA era: A population-based cohort study.

PubMed

Janjua, N Z; Islam, N; Wong, J; Yoshida, E M; Ramji, A; Samji, H; Butt, Z A; Chong, M; Cook, D; Alvarez, M; Darvishian, M; Tyndall, M; Krajden, M

2017-08-01

We evaluated the shift in the characteristics of people who received interferon-based hepatitis C virus (HCV) treatments and those who received recently introduced direct-acting antivirals (DAAs) in British Columbia (BC), Canada. The BC Hepatitis Testers Cohort includes 1.5 million individuals tested for HCV or HIV, or reported cases of hepatitis B and active tuberculosis in BC from 1990 to 2013 linked to medical visits, hospitalization, cancer, prescription drugs and mortality data. This analysis included all patients who filled at least one prescription for HCV treatment until 31 July 2015. HCV treatments were classified as older interferon-based treatments including pegylated interferon/ribavirin (PegIFN/RBV) with/without boceprevir or telaprevir, DAAs with RBV or PegIFN/RBV, and newer interferon-free DAAs. Of 11 886 people treated for HCV between 2000 and 2015, 1164 (9.8%) received interferon-free DAAs (ledipasvir/sofosbuvir: n=1075; 92.4%), while 452 (3.8%) received a combination of DAAs and RBV or PegIFN/RBV. Compared to those receiving interferon-based treatment, people with HIV co-infection (adjusted odds ratio [aOR]: 2.96, 95% CI: 2.31-3.81), cirrhosis (aOR: 1.77, 95% CI: 1.45-2.15), decompensated cirrhosis (aOR: 1.72, 95% CI: 1.31-2.28), diabetes (aOR: 1.30, 95% CI: 1.10-1.54), a history of injection drug use (aOR: 1.34, 95% CI: 1.09-1.65) and opioid substitution therapy (aOR: 1.30, 95% CI: 1.01-1.67) were more likely to receive interferon-free DAAs. Socio-economically marginalized individuals were significantly less likely (most deprived vs most privileged: aOR: 0.71, 95% CI: 0.58-0.87) to receive DAAs. In conclusion, there is a shift in prescription of new HCV treatments to previously excluded groups (eg HIV-co-infected), although gaps remain for the socio-economically marginalized populations. © 2017 John Wiley & Sons Ltd.

[New direct-acting antiviral agents for the treatment of chronic hepatitis C in 2014].

PubMed

Cornberg, M; Höner zu Siederdissen, C; Maasoumy, B; Manns, M P

2014-04-01

The development of direct-acting antiviral agents (DAA) against the hepatitis C virus (HCV) has seen enormous progress in recent years. In 2011, the first protease inhibitors boceprevir (BOC) and telaprevir (TLV) were approved, which still need to be combined with pegylated interferon α (PEG-IFN α) and ribavirin (RBV) and are used only in patients with genotype 1. With sofosbuvir (SOF) and simeprevir (SMV), two new DAA are available. More DAA are in clinical development. Which changes in the treatment of chronic hepatitis C infection can be expected with the approval of the new DAA in 2014? Relevant phase IIb and phase III studies for the approval in 2014 were considered for drugs approved by the FDA or EMA at the editorial deadline. For patients with genotype 1, the combination of SOF, SMV or faldaprevir with PEG-IFN α and RBV was successfully evaluated in phase III studies. In contrast to previous treatment with PEG-IFN α, RBV and telaprevir (TLV) or boceprevir (BOC), therapy can be shortened in most cases with a significantly improved side-effect profile. Cure rates above 80 % are possible. Data are also available for an interferon-free therapy with either SOF and RBV or SOF and SMV in GT-1 patients. SVR rates exceeding 60 % and up to 90 % are possible. However, treatment experience with these combinations is low and an unrestricted interferon-free therapy for genotype 1 should not be expected before 2015. For patients with genotypes 2 and 3, valid data for interferon-free therapies are available. The combination of SOF and RBV for 12 weeks in genotype 2 and 24 weeks for genotype 3 is effective and shows equal or superior cure rates with fewer side effects than the PEG-IFN α/RBV therapy. For patients with genotype 1, the duration of therapy can be further reduced with better side effect profile. In certain situations, therapy without PEG-IFN α is possible and should be considered. For patients with genotypes 2 and 3, an

Effectiveness, safety and clinical outcomes of direct-acting antiviral therapy in HCV genotype 1 infection: Results from a Spanish real-world cohort.

PubMed

Calleja, Jose Luis; Crespo, Javier; Rincón, Diego; Ruiz-Antorán, Belén; Fernandez, Inmaculada; Perelló, Christie; Gea, Francisco; Lens, Sabela; García-Samaniego, Javier; Sacristán, Begoña; García-Eliz, María; Llerena, Susana; Pascasio, Juan Manuel; Turnes, Juan; Torras, Xavier; Morillas, Rosa Maria; Llaneras, Jordi; Serra, Miguel A; Diago, Moises; Rodriguez, Conrado Fernández; Ampuero, Javier; Jorquera, Francisco; Simon, Miguel A; Arenas, Juan; Navascues, Carmen Alvarez; Bañares, Rafael; Muñoz, Raquel; Albillos, Agustin; Mariño, Zoe

2017-06-01

Clinical trials evaluating second-generation direct-acting antiviral agents (DAAs) have shown excellent rates of sustained virologic response (SVR) and good safety profiles in patients with chronic hepatitis C virus (HCV) genotype 1 infection. We aimed to investigate the effectiveness and safety of two oral DAA combination regimens, ombitasvir/paritaprevir/ritonavir plus dasabuvir (OMV/PTV/r+DSV) and ledipasvir/sofosbuvir (LDV/SOF), in a real-world clinical practice. Data from HCV genotype 1 patients treated with either OMV/PTV/r+DSV±ribavirin (RBV) (n=1567) or LDV/SOF±RBV (n=1758) in 35 centers across Spain between April 1, 2015 and February 28, 2016 were recorded in a large national database. Demographic, clinical and virological data were analyzed. Details of serious adverse events (SAEs) were recorded. The two cohorts were not matched with respect to baseline characteristics and could not be compared directly. The SVR12 rate was 96.8% with OMV/PTVr/DSV±RBV and 95.8% with LDV/SOF±RBV. No significant differences were observed in SVR according to HCV subgenotype (p=0.321 [OMV/PTV/r+DSV±RBV] and p=0.174 [LDV/SOF]) or degree of fibrosis (c0.548 [OMV/PTV/r/DSV±RBV] and p=0.085 [LDV/SOF]). Only baseline albumin level was significantly associated with failure to achieve SVR (p<0.05) on multivariate analysis. Rates of SAEs and SAE-associated treatment discontinuation were 5.4% and 1.7%, in the OMV/PTV/r+DSV subcohort and 5.5% and 1.5% in the LDV/SOF subcohort, respectively. Hepatocellular carcinoma (HCC) recurred in 30% of patients with a complete response to therapy for previous HCC. Incident HCC was reported in 0.93%. In this large cohort of patients managed in the real-world setting in Spain, OMV/PTV/r+DSV and LDV/SOF achieved high rates of SVR12, comparable to those observed in randomized controlled trials, with similarly good safety profiles. In clinical trials, second-generation direct-acting antiviral agents (DAAs) have been shown to cure over 90% of

Direct-acting antivirals combination for elderly patients with chronic hepatitis C: A cost-effectiveness analysis.

PubMed

Ciaccio, Antonio; Cortesi, Paolo A; Bellelli, Giuseppe; Rota, Matteo; Conti, Sara; Okolicsanyi, Stefano; Rota, Monica; Cesana, Giancarlo; Mantovani, Lorenzo G; Annoni, Giorgio; Strazzabosco, Mario

2017-07-01

Chronic hepatitis C (CHC) has been undertreated among elderly patients. Interferon-free treatment represents an opportunity for these patients. The aim of this study was to assess the cost-effectiveness of directly acting antivirals (DAAs) in CHC elderly patients. A Markov model of CHC natural history was built. This study focuses on CHC patients older than 65 years, stratified according to genotype (1/4, 2 and 3), liver fibrosis (METAVIR F1 to F4), age and frailty phenotype (robust, pre-frail and frail). DAAs combination vs no treatment was simulated for each theoretical population, assessing life years, quality-adjusted life years (QALYs), costs, incremental cost-effectiveness ratios (ICERs) in a lifetime time horizon and by the Healthcare System perspective. Incremental cost-effectiveness ratio increased with age and frailty status in all fibrosis stages. For robust F3 and F4 patients ICERs remained below the willingness-to-pay threshold (WTP) of 40 000€/QALY up to age 75 and 86 years, respectively, depending on drug price and sustained virological response probability (sensitivity analysis). Notably, in F4 and frail subjects older than 75 years, ICER was more sensitive to non-liver-related mortality rate. In elderly F1 and F2 patients, ICERs were below WTP only up to 77 years old, with wide variability among frailty phenotypes. Cost-effectiveness of DAAs treatment of elderly CHC patients is solid in those with advanced fibrosis, but it depends strongly on frailty status and age, particularly in patients with milder fibrosis stages. Accurate assessment of clinical variables, including frailty, is necessary to allocate limited resources to this special population. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Enabling Data-as- a-Service (DaaS) - Biggest Challenge of Geoscience Australia

NASA Astrophysics Data System (ADS)

Bastrakova, I.; Kemp, C.; Car, N. J.

2016-12-01

Geoscience Australia (GA) is recognised and respected as the national repository and steward of multiple national significance data collections that provides geoscience information, services and capability to the Australian Government, industry and stakeholders. Provision of Data-as-a-Service is both GA's key responsibility and core business. Through the Science First Transformation Program GA is undergoing a significant rethinking of its data architecture, curation and access to support the Digital Science capability for which DaaS forms both a dependency and underpins its implementation. DaaS, being a service, means we can deliver its outputs in multiple ways thus providing users with data on demand in ready-for-consumption forms. We can then to reuse prebuilt data constructions to allow self-serviced integration of data underpinned by dynamic query tools. In GA's context examples of DaaS are the Australian Geoscience Data Cube, the Foundation Spatial Data Framework and data served through several Virtual Laboratories. We have implemented a three-layered architecture for DaaS in order to store and manage the data while honouring the semantics of Scientific Data Models defined by subject matter experts and GA's Enterprise Data Architecture as well as retain that delivery flexibility. The foundation layer of DaaS is Canonical Datasets, which are optimised for a long-term data stewardship and curation. Data is well structured, standardised, described and audited. All data creation and editing happen within this layer. The middle Data Transformation layer assists with transformation of data from Canonical Datasets to data integration layer. It provides mechanisms for multi-format and multi-technology data transformation. The top Data Integration layer is optimised for data access. Data can be easily reused and repurposed; data formats made available are optimised for scientific computing and adjusted for access by multiple applications, tools and libraries. Moving to

Evolution of multi-drug resistant HCV clones from pre-existing resistant-associated variants during direct-acting antiviral therapy determined by third-generation sequencing

NASA Astrophysics Data System (ADS)

Takeda, Haruhiko; Ueda, Yoshihide; Inuzuka, Tadashi; Yamashita, Yukitaka; Osaki, Yukio; Nasu, Akihiro; Umeda, Makoto; Takemura, Ryo; Seno, Hiroshi; Sekine, Akihiro; Marusawa, Hiroyuki

2017-03-01

Resistance-associated variant (RAV) is one of the most significant clinical challenges in treating HCV-infected patients with direct-acting antivirals (DAAs). We investigated the viral dynamics in patients receiving DAAs using third-generation sequencing technology. Among 283 patients with genotype-1b HCV receiving daclatasvir + asunaprevir (DCV/ASV), 32 (11.3%) failed to achieve sustained virological response (SVR). Conventional ultra-deep sequencing of HCV genome was performed in 104 patients (32 non-SVR, 72 SVR), and detected representative RAVs in all non-SVR patients at baseline, including Y93H in 28 (87.5%). Long contiguous sequences spanning NS3 to NS5A regions of each viral clone in 12 sera from 6 representative non-SVR patients were determined by third-generation sequencing, and showed the concurrent presence of several synonymous mutations linked to resistance-associated substitutions in a subpopulation of pre-existing RAVs and dominant isolates at treatment failure. Phylogenetic analyses revealed close genetic distances between pre-existing RAVs and dominant RAVs at treatment failure. In addition, multiple drug-resistant mutations developed on pre-existing RAVs after DCV/ASV in all non-SVR cases. In conclusion, multi-drug resistant viral clones at treatment failure certainly originated from a subpopulation of pre-existing RAVs in HCV-infected patients. Those RAVs were selected for and became dominant with the acquisition of multiple resistance-associated substitutions under DAA treatment pressure.

Safety of Direct-Acting Antiviral Therapy Regarding Renal Function in Post-Liver Transplant Patients Infected with Hepatitis C Virus and a 100% 12-Week Sustained Virologic Response-A Single-Center Study.

PubMed

Peschel, G; Moleda, L; Baier, L; Selgrad, M; Schmid, S; Scherer, M N; Müller, M; Weigand, K

2018-06-01

Patients after liver transplantation (LT) with hepatitis C virus (HCV) infection often suffer from renal or hepatic impairment. Treating patients after LT with direct-acting antivirals (DAA) might result in decreasing renal function due to interaction of DAA and immunosuppressive therapy. In this single-center study we analyzed clinical parameters of 18 HCV-infected patients treated with DAA therapy after LT. The primary end points were change of renal function (glomerular filtration rate) and sustained virologic response 12 weeks after therapy (SVR12). For secondary end points, we investigated the influence of DAA therapy on transaminases, bilirubin, international normalized ratio, noninvasive fibrosis measurement, and Model for End-Stage Liver Disease (MELD) score. Five out of 18 patients treated with DAA suffered from renal impairment stage 2, and 7 patients of renal impairment stage 3. Renal function at SVR12 was not influenced by preexisting renal impairment (P > .5), type of immunosuppressant (P > .5), or type of DAA regimen (P > .5). All patients reached SVR12. The levels of transaminases and bilirubin declined rapidly, as expected. Ten out of 18 patients already suffered from cirrhosis or liver fibrosis >F3 according to noninvasive measurement before initiation of treatment. Single-point acoustic radiation force impulse imaging improved in 9 patients (P = .012). In 7 patients, MELD score improved owing to the decrease of bilirubin levels. In 6 patients it worsened. DAA therapy in LT patients was effective and safe in this single-center real-life cohort. Renal function was not influenced by the administered drug combinations, even in patients with preexisting renal impairment. Copyright © 2018. Published by Elsevier Inc.

Effectiveness of direct-acting antiviral therapy for hepatitis C in difficult-to-treat patients in a safety-net health system: a retrospective cohort study.

PubMed

Yek, Christina; de la Flor, Carolina; Marshall, John; Zoellner, Cindy; Thompson, Grace; Quirk, Lisa; Mayorga, Christian; Turner, Barbara J; Singal, Amit G; Jain, Mamta K

2017-11-20

Direct-acting antivirals (DAAs) have revolutionized chronic hepatitis C (HCV) treatment, but real-world effectiveness among vulnerable populations, including uninsured patients, is lacking. This study was conducted to characterize the effectiveness of DAAs in a socioeconomically disadvantaged and underinsured patient cohort. This retrospective observational study included all patients undergoing HCV treatment with DAA-based therapy between April 2014 and June 2016 at a large urban safety-net health system (Parkland Health and Hospital System, Dallas, TX, USA). The primary outcome was sustained virologic response (SVR), with secondary outcomes including treatment discontinuation, treatment relapse, and loss to follow-up. DAA-based therapy was initiated in 512 patients. The cohort was socioeconomically disadvantaged (56% uninsured and 13% Medicaid), with high historic rates of alcohol (41%) and substance (50%) use, and mental health disorders (38%). SVR was achieved in 90% of patients (n = 459); 26 patients (5%) were lost to follow-up. SVR was significantly lower in patients with decompensated cirrhosis (82% SVR; OR 0.37, 95% CI 0.16-0.85) but did not differ by insurance status (P = 0.98) or alcohol/substance use (P = 0.34). Reasons for treatment failure included loss to follow-up (n = 26, 5%), viral relapse (n = 16, 3%), non-treatment-related death (n = 7, 1%), and treatment discontinuation (n = 4, 1%). Of patients with viral relapse, 6 reported non-compliance and have not been retreated, 5 have been retreated and achieved SVR, 4 have undergone resistance testing but not yet initiated retreatment, and 1 was lost to follow-up. Effective outcomes with DAA-based therapy can be achieved in difficult-to-treat underinsured populations followed in resource-constrained safety-net health systems.

Analysis of UAS DAA Alerting in Fast-Time Simulations without DAA Mitigation

NASA Technical Reports Server (NTRS)

Thipphavong, David P.; Santiago, Confesor; Isaacson, Douglas R.; Lee, Seung Man; Park, Chunki; Refai, Mohamad Said; Snow, James

2015-01-01

Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA alerting system performance. A recent study conducted using NASA's ACES (Airspace Concept Evaluation System) simulation capability begins to address questions surrounding the development of draft MOPS for DAA alerting systems. ACES simulations were conducted to study the performance of alerting systems proposed by the SC-228 DAA Alerting sub-group. Analysis included but was not limited to: 1) correct alert (and timeliness), 2) false alert (and severity and duration), 3) missed alert, and 4) probability of an alert type at the time of loss of well clear. The performance of DAA alerting systems when using intent vs. dead-reckoning for UAS ownship trajectories was also compared. The results will be used by SC-228 to inform decisions about the surveillance standards of UAS DAA systems and future requirements development and validation efforts.

Direct Acting Anti-hepatitis C Virus Drugs: Clinical Pharmacology and Future Direction

PubMed Central

Geddawy, Ayman; Ibrahim, Yasmine F.; Elbahie, Nabil M.; Ibrahim, Mohammad A.

2017-01-01

Abstract Chronic hepatitis C virus (HCV) infection is a leading cause of chronic liver disease. The introduction of direct acting antiviral agents (DAAs) for its treatment represents a major advance in terms of sustained virologic response (SVR) rates and adverse effect profiles. Mechanistically, DAAs inhibit specific HCV non-structural proteins (NS) that are vital for its replication. Boceprevir, telaprevir, simeprevir, asunaprevir, grazoprevir and paritaprevir are NS3/4A inhibitors. Ombitasvir, ledipasvir, daclatasvir, elbasvir and velpatasvir are NS5A inhibitors. Sofosbuvir and dasabuvir are NS5B inhibitors. Currently, a combination of two or more DAAs is the corner stone for the treatment of HCV infection. However, the success of DAA therapy is facing several challenges, including the potential of drug-drug interactions and resistant variance. Moreover, the shortage of relevant clinical pharmacological data and drug interaction regarding DAA is a clinical concern. The present review discusses the clinical pharmacology of DAAs with special emphasis on drug-drug interaction. PMID:28680834

High HCV cure rates for people who use drugs treated with direct acting antiviral therapy at an urban primary care clinic.

PubMed

Norton, Brianna L; Fleming, Julia; Bachhuber, Marcus A; Steinman, Meredith; DeLuca, Joseph; Cunningham, Chinazo O; Johnson, Nirah; Laraque, Fabienne; Litwin, Alain H

2017-09-01

Though direct acting antivirals (DAAs) promise high cure rates, many providers and payers remain concerned about successful treatment for people who use drugs (PWUD), even among those engaged in opioid agonist treatment (OAT). The efficacy of DAAs among PWUD in real-world settings is unclear. We conducted a cohort study of patients initiating HCV treatment between January 2014 and August 2015 (n=89) at a primary care clinic in the Bronx, NY. Onsite HCV treatment with DAAs was performed by an HCV specialist, with support from a care coordinator funded by the NYC Department of Health. We identified four categories of drug use and drug treatment: (1) no active drug use/not receiving OAT (defined as non-PWUD); (2) no active drug use/receiving OAT; (3) active drug use/not receiving OAT; and (4) active drug use/receiving OAT. The primary outcome was SVR at 12 weeks post-treatment. Overall SVR rates were 95% (n=41/43) for non-PWUD and 96% (n=44/46) for patients actively using drugs and/or receiving OAT [p=0.95]. There were no differences in SVR rates by drug use or drug treatment category. Compared to non-PWUD, those with no active drug use/receiving OAT had 100% SVR (n=15/15; p=1.0), those actively using drugs/not receiving OAT had 90% SVR (n=9/10; p=0.47), and those actively using drugs/receiving OAT had 95% SVR (20/21; p=1.0). Regardless of active drug use or OAT, patients who received DAA therapy at an urban primary care clinic achieved high HCV cure rates. We found no clinical evidence to justify restricting access to HCV treatment for patients actively using drugs and/or receiving OAT. Copyright © 2017 Elsevier B.V. All rights reserved.

High HCV cure rates for people who use drugs treated with direct acting antiviral therapy at an urban primary care clinic

PubMed Central

Norton, Brianna L.; Fleming, Julia; Bachhuber, Marcus A.; Steinman, Meredith; DeLuca, Joseph; Cunningham, Chinazo O.; Johnson, Nirah; Laraque, Fabienne; Litwin, Alain H.

2018-01-01

Background Though direct acting antivirals (DAAs) promise high cure rates, many providers and payers remain concerned about successful treatment for people who use drugs (PWUD), even among those engaged in opioid agonist treatment (OAT). The efficacy of DAAs among PWUD in real-world settings is unclear. Methods We conducted a cohort study of patients initiating HCV treatment between January 2014 and August 2015 (n = 89) at a primary care clinic in the Bronx, NY. Onsite HCV treatment with DAAs was performed by an HCV specialist, with support from a care coordinator funded by the NYC Department of Health. We identified four categories of drug use and drug treatment: (1) no active drug use/not receiving OAT (defined as non-PWUD); (2) no active drug use/receiving OAT; (3) active drug use/not receiving OAT; and (4) active drug use/receiving OAT. The primary outcome was SVR at 12 weeks post-treatment. Results Overall SVR rates were 95% (n = 41/43) for non-PWUD and 96% (n = 44/46) for patients actively using drugs and/or receiving OAT [p = 0.95]. There were no differences in SVR rates by drug use or drug treatment category. Compared to non-PWUD, those with no active drug use/receiving OAT had 100% SVR (n = 15/15; p = 1.0), those actively using drugs/not receiving OAT had 90% SVR (n = 9/10; p = 0.47), and those actively using drugs/receiving OAT had 95% SVR (20/21; p = 1.0). Conclusion Regardless of active drug use or OAT, patients who received DAA therapy at an urban primary care clinic achieved high HCV cure rates. We found no clinical evidence to justify restricting access to HCV treatment for patients actively using drugs and/or receiving OAT. PMID:28811158

The clinical significance of drug-drug interactions in the era of direct-acting anti-viral agents against chronic hepatitis C.

PubMed

Maasoumy, B; Port, K; Calle Serrano, B; Markova, A A; Sollik, L; Manns, M P; Cornberg, M; Wedemeyer, H

2013-12-01

Drug-drug interactions (DDIs) in the treatment of chronic hepatitis C infection became a potential challenge with the introduction of direct-acting anti-virals (DAAs). Both currently approved DAAs, the protease inhibitors (PIs) telaprevir (TVR) and boceprevir (BOC), are substrates and inhibitors of P-glycoprotein and the cytochrome P450 3A4, which are regularly involved in DDIs. To analyse the risk for DDIs in patients with chronic HCV genotype 1 infection considered for PI treatment at a tertiary referral centre. The first 115 consecutive patients selected for a PI therapy at Hannover Medical School were included. All changes to co-medication before and during PI treatment were documented. Drugs were checked for DDIs with TVR and BOC using DDI websites and the respective prescribing information. Out-patient medication contained 116 different drugs. Median number of drugs/patient was 2 (range 0-11). The risk for DDIs was substantial for 38% of the drugs affecting 49% of patients. Only 4% of the drugs were strictly contraindicated. DDIs between a PI and drugs newly prescribed during anti-viral therapy were considerable in 42% of the patients. Suspected DDIs were managed by dose adjustments and discontinuation of co-medication in 7% and 21% of the patients respectively. Many patients with chronic HCV genotype 1 infection are affected by potential DDIs if treated with a protease inhibitor, but only in a minority of cases co-medication is strictly incompatible. Overall, the challenge of DDIs is time-consuming, but well manageable by a careful review of the patient's drug chart and monitoring during treatment. © 2013 John Wiley & Sons Ltd.

Direct-Acting Antiviral Therapy Outcomes in Canadian Chronic Hepatitis C Telemedicine Patients.

PubMed

Cooper, Curtis L; Hatashita, Holly; Corsi, Daniel J; Parmar, Parmvir; Corrin, Raymond; Garber, Gary

Many of the 300,000 HCV-infected Canadians live in under-served and remote areas without access to HCV healthcare specialists. Telemedicine (TM) and advances in HCV management can facilitate linkage of these marginalized patients to healthcare. A cohort database analysis was performed on patients followed at The Ottawa Hospital and Regional Viral Hepatitis Program between January 2012 and August 2016. We compared patient characteristics, fibrosis work-up and antiviral treatment outcomes in TM (n = 157) and non-TM (n = 1,130) patients (The Ottawa Hospital Viral Hepatitis Outpatient Clinic) residing in Eastern Ontario. TM patients were more often infected with genotype 3 (25.9% vs. 16.4%), were more commonly Indigenous (7.0% vs. 2.2%) had a history of injection drug use (70.1% vs. 54.9%) and incarceration (46.5% vs 35.5%). Groups were comparable in age (48.9 years), gender (63.7% male) and cirrhotic stage (24.0%). 59.2% of TM patients underwent transient elastography during regional outreach blitzes compared to 61.8% of non-TM patients (p = 0.54). Overall, half as many TM patients initiated antiviral therapy as non-TM patients (27.4% vs. 53.8%, p < 0.001). The introduction of DAA regimens is bridging this gap (22.2% of TM patients vs. 34.3% of non-TM patients). SVR rates with interferon-free, DAA regimens were 94.7% and 94.8% in TM and non-TM groups (p = 0.99). Our TM program engages and retains a population that faces many barriers to effective HCV treatment. TM patients initiated HCV therapy and achieved High SVR rates comparable to those obtained using traditional models of care.

Hepatitis B Virus Reactivation Associated With Direct-Acting Antiviral Therapy for Chronic Hepatitis C Virus: A Review of Cases Reported to the U.S. Food and Drug Administration Adverse Event Reporting System.

PubMed

Bersoff-Matcha, Susan J; Cao, Kelly; Jason, Mihaela; Ajao, Adebola; Jones, S Christopher; Meyer, Tamra; Brinker, Allen

2017-06-06

Direct-acting antiviral agents (DAAs) are used increasingly to treat hepatitis C virus (HCV) infection. Reports were published recently on hepatitis B virus (HBV) reactivation (HBV-R) in patients with HBV-HCV co-infection. Hepatitis B virus reactivation, defined as an abrupt increase in HBV replication in patients with inactive or resolved HBV infection, may result in clinically significant hepatitis. To assess whether HBV-R is a safety concern in patients receiving HCV DAAs. Descriptive case series. U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). 29 patients with HBV-R receiving HCV DAAs. Clinical and laboratory data. The FDA identified 29 unique reports of HBV-R in patients receiving DAAs from 22 November 2013 to 15 October 2016. Two cases resulted in death and 1 case in liver transplantation. Patients in whom HBV-R developed were heterogeneous regarding HCV genotype, DAAs received, and baseline HBV characteristics. At baseline, 9 patients had a detectable HBV viral load, 7 had positive results on hepatitis B surface antigen (HBsAg) testing and had an undetectable HBV viral load, and 3 had negative results on HBsAg testing and had an undetectable HBV viral load. For the remaining 10 patients, data points were not reported or the data were uninterpretable. Despite provider knowledge of baseline HBV, HBV-R diagnosis and treatment were delayed in 7 cases and possibly 7 others. The quality of information varied among reports. Because reporting is voluntary, HBV-R associated with DAAs likely is underreported. Hepatitis B virus reactivation is a newly identified safety concern in patients with HBV-HCV co-infection treated with DAAs. Patients with a history of HBV require clinical monitoring while receiving DAA therapy. Studies would help determine the risk factors for HBV-R, define monitoring frequency, and identify patients who may benefit from HBV prophylaxis and treatment. DAAs remain a safe and highly effective treatment for the

Future mobile access for open-data platforms and the BBC-DaaS system

NASA Astrophysics Data System (ADS)

Edlich, Stefan; Singh, Sonam; Pfennigstorf, Ingo

2013-03-01

In this paper, we develop an open data platform on multimedia devices to act as marketplace of data for information seekers and data providers. We explore the important aspects of Data-as-a-Service (DaaS) service in the cloud with a mobile access point. The basis of the DaaS service is to act as a marketplace for information, utilizing new technologies and recent new scalable polyglot architectures based on NoSql databases. Whereas Open-Data platforms are beginning to be widely accepted, its mobile use is not. We compare similar products, their approach and a possible mobile usage. We discuss several approaches to address the mobile access as a native app, html5 and a mobile first approach together with the several frontend presentation techniques. Big data visualization itself is in the early days and we explore some possibilities to get big data / open data accessed by mobile users.

Analysis of UAS DAA Surveillance in Fast-Time Simulations without DAA Mitigation

NASA Technical Reports Server (NTRS)

Thipphavong, David P.; Santiago, Confesor; Isaacson, David R.; Lee, Seung Man; Refai, Mohamad Said; Snow, James William

2015-01-01

Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA surveillance system performance. A recent study conducted using NASA's ACES (Airspace Concept Evaluation System) simulation capability begins to address questions surrounding the development of draft MOPS for DAA surveillance systems. ACES simulations were conducted to study the performance of sensor systems proposed by the SC-228 DAA Surveillance sub-group. Analysis included but was not limited to: 1) number of intruders (both IFR and VFR) detected by all sensors as a function of UAS flight time, 2) number of intruders (both IFR and VFR) detected by radar alone as a function of UAS flight time, and 3) number of VFR intruders detected by all sensors as a function of UAS flight time. The results will be used by SC-228 to inform decisions about the surveillance standards of UAS DAA systems and future requirements development and validation efforts.

HCV mono-infected and HIV/HCV co-infected individuals treated with direct-acting antivirals: to what extent do they differ?

PubMed

Bruno, Giuseppe; Saracino, Annalisa; Scudeller, Luigia; Fabrizio, Claudia; Dell'Acqua, Raffaele; Milano, Eugenio; Milella, Michele; Ladisa, Nicoletta; Monno, Laura; Angarano, Gioacchino

2017-09-01

Direct-acting antiviral (DAA)-based treatment of hepatitis C virus (HCV) has been associated with high sustained virological response (SVR) rates and good tolerability in randomized clinical trials. This study was performed to assess the safety and effectiveness of DAAs in both HCV mono-infected and HIV/HCV co-infected patients. All consecutive HCV-infected patients, including HIV/HCV co-infected patients, receiving DAA-based treatment from February 2015 to September 2016 at the study clinic were included. Clinical, virological, and biochemical data were retrieved. The primary end-point was the SVR12 (HCV RNA undetectable 12 weeks after the end of treatment) is commonly used worldwide. The secondary end-point was the safety profile of DAAs during the treatment period. A total of 382 patients were included; 62 were HIV/HCV co-infected. Cirrhosis was found in 256 patients (67.4%). SVR12 was achieved in 365/382 (95.5%) individuals (58/62 HIV/HCV co-infected, 93.5%) in the intention-to-treat (ITT) analysis. A platelet count <90×10 9 /l (odds ratio (OR) 4.12, 95% confidence interval (CI) 1.5-11.3, p=0.006), HCV genotype 3 infection (OR 5.49, 95% CI 1.9-15.7, p=0.002), liver stiffness >20kPa (OR 3.05, 95% CI 1.03-8.96, p=0.04), and Model for End-Stage Liver Disease (MELD) score >10 (OR 5.27, 95% CI 1.16-23.8, p=0.03) were associated with lower SVR rates. On multivariate analysis, only genotype 3 infection remained a negative predictor of SVR (OR 21.6, 95% CI 3.81-123, p=0.001). Treatment discontinuation was observed in 10 subjects. Severe adverse events (SAEs) occurred in 17 patients (4.5%). High SVR12 rates were observed in both HCV mono-infected and HIV/HCV co-infected individuals. Overall, DAA-based treatment was safe and there were no differences in terms of SAEs and treatment discontinuation between the two groups. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Reactivation of hepatitis B in patients of chronic hepatitis C with hepatitis B virus infection treated with direct acting antivirals.

PubMed

Yeh, Ming-Lun; Huang, Chung-Feng; Hsieh, Meng-Hsuan; Ko, Yu-Min; Chen, Kuan-Yu; Liu, Ta-Wei; Lin, Yi-Hung; Liang, Po-Cheng; Hsieh, Ming-Yen; Lin, Zu-Yau; Chen, Shinn-Cherng; Huang, Ching-I; Huang, Jee-Fu; Kuo, Po-Lin; Dai, Chia-Yen; Yu, Ming-Lung; Chuang, Wan-Long

2017-10-01

Hepatitis B virus (HBV) may reactivate when treating chronic hepatitis C (CHC) with direct acting antivirals (DAA). We aim to investigate the risk of HBV reactivation during DAA therapy. Chronic hepatitis C patients receiving pan-oral DAA therapy from December 2013 to August 2016 were evaluated. Fifty-seven patients that had a past HBV infection (negative hepatitis B surface antigen [HBsAg] and positive hepatitis B core antibody) and seven patients that had a current HBV infection (positive HBsAg) were enrolled. Serum HBV and hepatitis C virus (HCV) markers were regularly measured. The endpoints were the HCV sustained virological response (SVR) and the HBV virological/clinical reactivation. The overall SVR 12 rate was 96.9%, and two patients, one with positive HBsAg, had a relapse of HCV. No episodes of HBV virological reactivation were observed among the patients with a past HBV infection. For the seven patients with a current HBV infection, HBV virological reactivation was found in four (57.1%) of the seven patients. Clinical reactivation of HBV was observed in one patient with pretreatment detectable HBV DNA and recovered after entecavir administration. For the other three patients with HBV virological reactivation, the reappearance of low level HBV DNA without clinical reactivation was observed. HBsAg levels demonstrated only small fluctuations in all the patients. There was a minimal impact of hepatitis B core antibody seropositivity on HCV efficacy and safety. For CHC patients with current HBV infection, the risk of HBV reactivation was present, and monitoring the HBV DNA level during therapy is warranted. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Final Report of Unmet Needs of Interferon-Based Therapy for Chronic Hepatitis C in Korea: Basis for Moving into the Direct-Acting Antiviral Era

PubMed Central

Jang, Eun Sun; Kim, Young Seok; Kim, Kyung-Ah; Lee, Youn Jae; Chung, Woo Jin; Kim, In Hee; Lee, Byung Seok; Jeong, Sook-Hyang

2017-01-01

Background/Aims To evaluate the era of direct acting antivirals (DAAs), we must understand the treatment patterns and outcomes of interferon-based therapy for hepatitis C virus (HCV) infection. We aimed to elucidate the treatment rate, factors affecting treatment decisions, and efficacy of interferon-based therapy in a real-world setting. Methods This nationwide cohort study included 1,191 newly diagnosed patients with chronic HCV infection at seven tertiary hospitals in South Korea. Subjects were followed retrospectively until March 2015, which was just before the approval of DAA therapy. Results In total, 48.2% and 49.3% of the patients had HCV genotypes 1 and 2, respectively. Interferon-based therapy was initiated in 541 patients (45.4%). The major reasons for no treatment included ineligibility (18.9%), concern about adverse events (22.3%), cost (21.5%), and an age >75 years (19.5%). Interferon-based therapy was discontinued (18.5%) mainly due to adverse events (n=66). The intent-to-treat analysis found that the sustained virologic response (SVR) rate was 58.3% in genotype 1 patients and 74.7% in non-genotype 1 patients. Conclusions Approximately one-third of newly diagnosed HCV patients in South Korea received interferon-based therapy and showed a suboptimal SVR rate. Diagnosis of patients at younger ages and with a less advanced liver status and reducing the DAA therapy cost may fulfill unmet needs. PMID:28506027

Changes in liver stiffness and steatosis among patients with hepatitis C virus infection who received direct-acting antiviral therapy and achieved sustained virological response.

PubMed

Kobayashi, Natsuko; Iijima, Hiroko; Tada, Toshifumi; Kumada, Takashi; Yoshida, Masahiro; Aoki, Tomoko; Nishimura, Takashi; Nakano, Chikage; Takata, Ryo; Yoh, Kazunori; Ishii, Akio; Takashima, Tomoyuki; Sakai, Yoshiyuki; Aizawa, Nobuhiro; Nishikawa, Hiroki; Ikeda, Naoto; Iwata, Yoshinori; Enomoto, Hirayuki; Hirota, Seiichi; Fujimoto, Jiro; Nishiguchi, Shuhei

2018-05-01

Whether direct-acting antiviral (DAA) therapy can reduce liver fibrosis and steatosis in patients with chronic hepatitis C virus (HCV) infection remains unclear. We evaluated sequential changes in liver stiffness and steatosis using transient elastography (TE) and the TE-based controlled attenuation parameter (CAP) in patients with HCV who received DAA therapy. A total of 57 patients with HCV who received DAA therapy and achieved sustained virological response (SVR) were analyzed. Liver stiffness as evaluated with TE, steatosis as evaluated with CAP, and laboratory data were assessed before treatment (baseline), at end of treatment (EOT), 24 weeks after EOT (SVR24), and 48 weeks after EOT (SVR48). Alanine aminotransferase levels, corresponding to the presence of necroinflammatory activity, significantly decreased overall, with significant differences between baseline and EOT, EOT, and SVR24, and baseline and SVR48. However, alanine aminotransferase levels showed no significant changes between SVR24 and SVR48. Median (interquartile range) liver stiffness values at baseline, EOT, SVR24, and SVR48 were 8.3 (5.0-14.8), 7.4 (4.6-14.7), 5.3 (4.1-11.8), and 5.4 (4.0-13.4) kPa, respectively (baseline vs. EOT, P=0.044; EOT vs. SVR24, P=0.011; and SVR24 vs. SVR48, P=0.054). In patients with fatty liver (CAP≥236 dB/m, n=14), CAP values at baseline and SVR48 were 253 (245-278) and 229 (209-249) dB/m, respectively (P=0.020). Liver stiffness at SVR24 might reflect liver fibrosis in the patients who received DAA therapy and achieved SVR. In addition, liver steatosis reduces in the same cohort with fatty liver.

Systematic Review of Modelling Approaches for the Cost Effectiveness of Hepatitis C Treatment with Direct-Acting Antivirals.

PubMed

Chhatwal, Jagpreet; He, Tianhua; Lopez-Olivo, Maria A

2016-06-01

New direct-acting antivirals (DAAs) are highly effective for hepatitis C virus (HCV) treatment. However, their prices have been widely debated. Decision-analytic models can project the long-term value of HCV treatment. Therefore, understanding of the methods used in these models and how they could influence results is important. Our objective was to describe and systematically review the methodological approaches in published cost-effectiveness models of chronic HCV treatment with DAAs. We searched several electronic databases, including Medline, Embase and EconLit, from 2011 to 2015. Study selection was performed by two reviewers independently. We included any cost-effectiveness analysis comparing DAAs with the old standard of care for HCV treatment. We excluded non-English-language studies and studies not reporting quality-adjusted life-years. One reviewer collected data and assessed the quality of reporting, using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement. Another reviewer crosschecked the abstracted information. The development methods of the included studies were synthetized on the basis of good modelling practice recommendations. Review of 304 citations revealed 36 cost-effectiveness analyses. The reporting quality scores of most articles were rated as acceptable, between 67 and 100 %. The majority of the studies were conducted in Europe (50 %), followed by the USA (44 %). Fifty-six percent of the 36 studies evaluated the cost effectiveness of HCV treatment in both treatment-naive and treatment-experienced patients, 97 % included genotype 1 patients and 53 % evaluated the cost effectiveness of second-generation or oral DAAs in comparison with the previous standard of care or other DAAs. Twenty-one models defined health states in terms of METAVIR fibrosis scores. Only one study used a discrete-event simulation approach, and the remainder used state-transition models. The time horizons varied; however, 89 % of

Pros and Cons: Usage of organs from donors infected with hepatitis C virus - Revision in the direct-acting antiviral era.

PubMed

Coilly, Audrey; Samuel, Didier

2016-01-01

Should organs from hepatitis C antibody positive donors (HCVD+) be used for transplantation? Organ shortage forces transplant teams to use donors with extended criteria. The decision to transplant a HCVD+ graft is a balance between the risk of transmission of a virus that could lead to end-stage liver diseases and the benefit of access to transplantation, specifically in patients with life-threatening disease. The other issue is the impact of HCV-related liver fibrosis in the donor graft on the long-term outcome in the recipient. Thus, the use of HCVD+ demonstrated a shorter meantime on the waiting list in kidney transplantation. When a HCVD+ graft is transplanted, the risk of HCV transmission depends on; 1) the quality of screening of the donor; 2) the presence of viral replication in the donor at the time of transplantation and the ability to detect it; and 3) the HCV status of the recipient but also the type of transplanted organ. In liver transplantation, the use of HCVD+ graft is usually restricted to recipients with a chronic HCV infection. Several reports showed some competition between HCV donor and recipient strain without deleterious impact on graft and patient survival. Controversies are still pending regarding the quality of the graft and the progression of fibrosis. The recent approval of direct-acting antiviral agents (DAA) dramatically changes the landscape of HCV infection treatment. After transplantation, combinations of DAA show high efficacy and good safety profile. In the near future, extensive use of DAA should reduce the number of HCVD+ with a positive HCV RNA, limiting the risk of transmission but also the number of patients on waiting lists for a disease related to HCV. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Risk of hepatitis B virus reactivation with direct-acting antivirals against hepatitis C virus: A cohort study from Egypt and meta-analysis of published data.

PubMed

El Kassas, Mohamed; Shimakawa, Yusuke; Ali-Eldin, Zainab; Funk, Anna-Louise; Wifi, Mohamed Naguib; Zaky, Samy; El-Raey, Fathiya; Esmat, Gamal; Fontanet, Arnaud

2018-05-08

Hepatitis B virus (HBV) reactivation in chronic hepatitis C (CHC) patients treated with direct-acting antivirals (DAAs) became an issue. However, its frequency has been poorly estimated, because of the varying definitions used and evaluation of heterogeneous study populations, including those concurrently treated for HBV. We prospectively followed HBV surface antigen (HBsAg)-positive Egyptians undergoing interferon-free DAAs, to estimate the risk of HBV reactivation and HBV-related hepatitis. We also conducted a meta-analysis to estimate the reactivation risk using published data obtained from a systematic review of PubMed/Embase, in addition to our Egyptian data. We applied a standard definition of HBV reactivation proposed by the international liver associations (APASL and AASLD). Of 4471 CHC patients, 35 HBsAg-positive patients started interferon-free DAAs without HBV nucleos(t)ide analogues in our Egyptian cohort. Ten experienced HBV reactivation (28.6%), of whom 1 developed hepatitis (10.0%). Our systematic review identified 18 papers. The pooled reactivation risk in HBsAg-positive patients was 18.2% (95% CI: 7.9%-30.7%) without HBV therapy and 0.0% (95% CI: 0.0%-0.0%) with HBV nucleos(t)ide analogue. The pooled risk of hepatitis in those with HBV reactivation was 12.6% (95% CI: 0.0%-34.7%). The pooled reactivation risk in HBsAg-negative, antibody to HBV core antigen-positive (anti-HBc-positive) patients was negligible (0.1%, 95% CI: 0.0%-0.3%), irrespective of the presence of antibody to HBsAg (anti-HBs). We confirmed high HBV reactivation risk in HBsAg-positive patients undergoing DAAs, with only a minority developing clinically important hepatitis. The risk is negligible for HBsAg-negative anti-HBc-positive patients. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Treatment of patients waitlisted for liver transplant with all-oral direct-acting antivirals is a cost-effective treatment strategy in the United States.

PubMed

Ahmed, Aijaz; Gonzalez, Stevan A; Cholankeril, George; Perumpail, Ryan B; McGinnis, Justin; Saab, Sammy; Beckerman, Rachel; Younossi, Zobair M

2017-07-01

All-oral direct acting antivirals (DAAs) have been shown to have high safety and efficacy in treating patients with hepatitis C virus (HCV) awaiting liver transplant (LT). However, there is limited empirical evidence comparing the health and economic outcomes associated with treating patients pre-LT versus post-LT. The objective of this study was to analyze the cost-effectiveness of pre-LT versus post-LT treatment with an all-oral DAA regimen among HCV patients with hepatocellular carcinoma (HCC) or decompensated cirrhosis (DCC). We constructed decision-analytic Markov models of the natural disease progression of HCV in HCC patients and DCC patients waitlisted for LT. The model followed hypothetical cohorts of 1,000 patients with a mean age of 50 over a 30-year time horizon from a third-party US payer perspective and estimated their health and cost outcomes based on pre-LT versus post-LT treatment with an all-oral DAA regimen. Transition probabilities and utilities were based on the literature and hepatologist consensus. Sustained virological response rates were sourced from ASTRAL-4, SOLAR-1, and SOLAR-2. Costs were sourced from RedBook, Medicare fee schedules, and published literature. In the HCC analysis, the pre-LT treatment strategy resulted in 11.48 per-patient quality-adjusted life years and $365,948 per patient lifetime costs versus 10.39 and $283,696, respectively, in the post-LT arm. In the DCC analysis, the pre-LT treatment strategy resulted in 9.27 per-patient quality-adjusted life years and $304,800 per patient lifetime costs versus 8.7 and $283,789, respectively, in the post-LT arm. As such, the pre-LT treatment strategy was found to be the most cost-effective in both populations with an incremental cost-effectiveness ratio of $74,255 (HCC) and $36,583 (DCC). Sensitivity and scenario analyses showed that results were most sensitive to the utility of patients post-LT, treatment sustained virological response rates, LT costs, and baseline Model for End

Evolution and Persistence of the Resistance-Associated Substitutions of Hepatitis C Virus after Direct-Acting Antiviral Treatment Failures.

PubMed

Jeong, Yechan; Jin, Bora; Lee, Hye Won; Park, Hye Jung; Park, Jun Yong; Kim, Do Young; Han, Kwang-Hyub; Ahn, Sang Hoon; Kim, Seungtaek

2018-05-16

Daclatasvir plus asunaprevir (DCV+ASV) treatment is an all-oral direct-acting antiviral (DAA) therapy for the genotype 1b HCV-infected patients. In this study, we investigated how resistance-associated substitutions (RASs) evolved after treatment failures and assessed the effect of those substitutions on viral fitness. Sequencing of NS5A and NS3 revealed typical RASs after treatment failures. Interestingly, the RASs of NS3 reverted to the wild-type amino acid within one year after treatment failures. However, the RASs of NS5A were stable and did not change. The effect of NS5A and NS3 RASs on viral RNA replication was assessed after mutagenic substitution in the genotype 1b HCV RNA. Among the single substitutions, the effect of D168V was more substantial than the others and the effect of the triple mutant combination (D168V+L31V+Y93H) was the most severe. The RAS at NS5A Y93 affected both viral RNA replication and virus production. Finally, the effect of trans-complementation of NS5A was demonstrated in our co-transfection experiments and these results suggest that such a trans-complementation effect of NS5A may help maintain the NS5A RASs for a long time even after cessation of the DAA treatment. In conclusion, the results from this investigation would help understand the emergence and persistence of RASs. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Improvement of liver stiffness in patients with hepatitis C virus infection who received direct-acting antiviral therapy and achieved sustained virological response.

PubMed

Tada, Toshifumi; Kumada, Takashi; Toyoda, Hidenori; Mizuno, Kazuyuki; Sone, Yasuhiro; Kataoka, Saki; Hashinokuchi, Shinichi

2017-12-01

There is insufficient research on whether direct-acting antiviral (DAA) therapy can improve liver fibrosis in patients with chronic hepatitis C virus (HCV). We evaluated sequential changes in liver stiffness using shear wave elastography in patients with HCV who received DAA therapy. A total of 210 patients with HCV who received daclatasvir and asunaprevir therapy and achieved sustained virological response (SVR) were analyzed. Liver stiffness, as evaluated by shear wave elastography, and laboratory data were assessed before treatment (baseline), at end of treatment (EOT), and at 24 weeks after EOT (SVR24). Alanine aminotransferase levels (ALT) decreased over time, and there were significant differences between baseline and EOT and between EOT and SVR24. Although platelet counts did not significantly differ between baseline and EOT, they increased significantly from EOT to SVR24. The median (interquartile range) liver stiffness values at baseline, EOT, and SVR24 were 10.2 (7.7-14.7), 8.8 (7.1-12.1), and 7.6 (6.3-10.3) kPa, respectively (P < 0.001, baseline vs EOT; P < 0.001, EOT vs SVR24). Additionally, in patients with ALT ≤ 30 (indicating low necroinflammatory activity in the liver) and Fibrosis-4 index > 2.0 (n = 75), the liver stiffness values at baseline, EOT, and SVR24 were 9.6 (7.7-15.2), 9.2 (7.3-12.1), and 7.7 (6.3-10.1) kPa, respectively (P < 0.001, baseline vs EOT; P < 0.001, EOT vs SVR24). These results suggest that early improvement of liver stiffness starts during the administration of DAAs in patients who achieve SVR, and this effect is particularly pronounced in patients with progressive liver fibrosis. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Geno2pheno[HCV] – A Web-based Interpretation System to Support Hepatitis C Treatment Decisions in the Era of Direct-Acting Antiviral Agents

PubMed Central

Kalaghatgi, Prabhav; Sikorski, Anna Maria; Knops, Elena; Rupp, Daniel; Sierra, Saleta; Heger, Eva; Neumann-Fraune, Maria; Beggel, Bastian; Walker, Andreas; Timm, Jörg; Walter, Hauke; Obermeier, Martin; Kaiser, Rolf; Bartenschlager, Ralf; Lengauer, Thomas

2016-01-01

The face of hepatitis C virus (HCV) therapy is changing dramatically. Direct-acting antiviral agents (DAAs) specifically targeting HCV proteins have been developed and entered clinical practice in 2011. However, despite high sustained viral response (SVR) rates of more than 90%, a fraction of patients do not eliminate the virus and in these cases treatment failure has been associated with the selection of drug resistance mutations (RAMs). RAMs may be prevalent prior to the start of treatment, or can be selected under therapy, and furthermore they can persist after cessation of treatment. Additionally, certain DAAs have been approved only for distinct HCV genotypes and may even have subtype specificity. Thus, sequence analysis before start of therapy is instrumental for managing DAA-based treatment strategies. We have created the interpretation system geno2pheno[HCV] (g2p[HCV]) to analyse HCV sequence data with respect to viral subtype and to predict drug resistance. Extensive reviewing and weighting of literature related to HCV drug resistance was performed to create a comprehensive list of drug resistance rules for inhibitors of the HCV protease in non-structural protein 3 (NS3-protease: Boceprevir, Paritaprevir, Simeprevir, Asunaprevir, Grazoprevir and Telaprevir), the NS5A replicase factor (Daclatasvir, Ledipasvir, Elbasvir and Ombitasvir), and the NS5B RNA-dependent RNA polymerase (Dasabuvir and Sofosbuvir). Upon submission of up to eight sequences, g2p[HCV] aligns the input sequences, identifies the genomic region(s), predicts the HCV geno- and subtypes, and generates for each DAA a drug resistance prediction report. g2p[HCV] offers easy-to-use and fast subtype and resistance analysis of HCV sequences, is continuously updated and freely accessible under http://hcv.geno2pheno.org/index.php. The system was partially validated with respect to the NS3-protease inhibitors Boceprevir, Telaprevir and Simeprevir by using data generated with recombinant, phenotypic

A New Age-Structured Multiscale Model of the Hepatitis C Virus Life-Cycle During Infection and Therapy With Direct-Acting Antiviral Agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quintela, Barbara de M.; Conway, Jessica M.; Hyman, James M.

Here, the dynamics of hepatitis C virus (HCV) RNA during translation and replication within infected cells were added to a previous age-structured multiscale mathematical model of HCV infection and treatment. The model allows the study of the dynamics of HCV RNA inside infected cells as well as the release of virus from infected cells and the dynamics of subsequent new cell infections. The model was used to fit in vitro data and estimate parameters characterizing HCV replication. This is the first model to our knowledge to consider both positive and negative strands of HCV RNA with an age-structured multiscale modelingmore » approach. Using this model we also studied the effects of direct-acting antiviral agents (DAAs) in blocking HCV RNA intracellular replication and the release of new virions and fit the model to in vivo data obtained from HCV-infected subjects under therapy.« less

A New Age-Structured Multiscale Model of the Hepatitis C Virus Life-Cycle During Infection and Therapy With Direct-Acting Antiviral Agents

DOE PAGES

Quintela, Barbara de M.; Conway, Jessica M.; Hyman, James M.; ...

2018-04-04

Here, the dynamics of hepatitis C virus (HCV) RNA during translation and replication within infected cells were added to a previous age-structured multiscale mathematical model of HCV infection and treatment. The model allows the study of the dynamics of HCV RNA inside infected cells as well as the release of virus from infected cells and the dynamics of subsequent new cell infections. The model was used to fit in vitro data and estimate parameters characterizing HCV replication. This is the first model to our knowledge to consider both positive and negative strands of HCV RNA with an age-structured multiscale modelingmore » approach. Using this model we also studied the effects of direct-acting antiviral agents (DAAs) in blocking HCV RNA intracellular replication and the release of new virions and fit the model to in vivo data obtained from HCV-infected subjects under therapy.« less

Delivering direct acting antiviral therapy for hepatitis C to highly marginalised and current drug injecting populations in a targeted primary health care setting.

PubMed

Read, Phillip; Lothian, Rebecca; Chronister, Karen; Gilliver, Rosie; Kearley, John; Dore, Gregory J; van Beek, Ingrid

2017-09-01

The Kirketon Road Centre (KRC) is a community-based public health facility in Sydney, Australia, that provides healthcare to people who inject drugs (PWID), including hepatitis C virus (HCV) treatment. From March 2016, the Australian Government has provided access to direct-acting antivirals (DAA) for adults with chronic HCV, without liver disease stage or drug and alcohol use restrictions. The aim of this study was to report DAA treatment outcomes among highly marginalised PWID treated at KRC. All individuals initiating DAA treatment at KRC and due for sustained virological response (SVR12) testing by end 2016 were included. Demographic, drug use behaviour, clinical parameters, adherence support and HCV treatment outcomes, including SVR12 were recorded. Factors associated with SVR12, loss-to-follow-up (LTFU) and delayed SVR12 testing (>SVR16) were assessed by multivariate analysis. SVR12 was assessed by intention-to-treat (ITT) and modified ITT, the latter excluding individuals with an end-of-treatment response (ETR) but no SVR12 assessment, or who postponed their SVR12 date due to treatment interruption. A total of 72 individuals commencing DAAs were included, of whom 67% were male, 30% homeless, and 32% Aboriginal. All had a lifetime history of injecting drug use, with 75% having injected within the last six months, and 44% injecting at least weekly; 25% were also enrolled in opioid substitution therapy. Twenty-five (35%) individuals elected to receive an enhanced adherence-support package. Fifty-nine of 72 (82%) individuals due for SVR12 attended for testing, of whom 59/59 (100%) achieved SVR, providing an ITT SVR of 82%. A further six individuals had undetectable HCV RNA at ETR, but no SVR12 assessment, and one interrupted treatment, providing a mITT SVR of 91%. Homelessness was associated with delayed SVR12 testing (OR 24.9 95%CI 2.9-212.8, p=0.003). There was no association between LTFU and frequency of drug injection, last drug injected, or planned

Demonstration Advanced Avionics System (DAAS) function description

NASA Technical Reports Server (NTRS)

Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

1982-01-01

The Demonstration Advanced Avionics System, DAAS, is an integrated avionics system utilizing microprocessor technologies, data busing, and shared displays for demonstrating the potential of these technologies in improving the safety and utility of general aviation operations in the late 1980's and beyond. Major hardware elements of the DAAS include a functionally distributed microcomputer complex, an integrated data control center, an electronic horizontal situation indicator, and a radio adaptor unit. All processing and display resources are interconnected by an IEEE-488 bus in order to enhance the overall system effectiveness, reliability, modularity and maintainability. A detail description of the DAAS architecture, the DAAS hardware, and the DAAS functions is presented. The system is designed for installation and flight test in a NASA Cessna 402-B aircraft.

Can Hepatitis C Virus (HCV) Direct-Acting Antiviral Treatment as Prevention Reverse the HCV Epidemic Among Men Who Have Sex With Men in the United Kingdom? Epidemiological and Modeling Insights.

PubMed

Martin, Natasha K; Thornton, Alicia; Hickman, Matthew; Sabin, Caroline; Nelson, Mark; Cooke, Graham S; Martin, Thomas C S; Delpech, Valerie; Ruf, Murad; Price, Huw; Azad, Yusef; Thomson, Emma C; Vickerman, Peter

2016-05-01

We report on the hepatitis C virus (HCV) epidemic among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) in the United Kingdom and model its trajectory with or without scaled-up HCV direct-acting antivirals (DAAs). A dynamic HCV transmission model among HIV-diagnosed MSM in the United Kingdom was calibrated to HCV prevalence (antibody [Ab] or RNA positive), incidence, and treatment from 2004 to 2011 among HIV-diagnosed MSM in the UK Collaborative HIV Cohort (UK CHIC). The epidemic was projected with current or scaled-up HCV treatment, with or without a 20% behavioral risk reduction. HCV prevalence among HIV-positive MSM in UK CHIC increased from 7.3% in 2004 to 9.9% in 2011, whereas primary incidence was flat (1.02-1.38 per 100 person-years). Over the next decade, modeling suggests 94% of infections are attributable to high-risk individuals, comprising 7% of the population. Without treatment, HCV chronic prevalence could have been 38% higher in 2015 (11.9% vs 8.6%). With current treatment and sustained virological response rates (status quo), chronic prevalence is likely to increase to 11% by 2025, but stabilize with DAA introduction in 2015. With DAA scale-up to 80% within 1 year of diagnosis (regardless of disease stage), and 20% per year thereafter, chronic prevalence could decline by 71% (to 3.2%) compared to status quo in 2025. With additional behavioral interventions, chronic prevalence could decline further to <2.5% by 2025. Epidemiological data and modeling suggest a continuing HCV epidemic among HIV-diagnosed MSM in the United Kingdom driven by high-risk individuals, despite high treatment rates. Substantial reductions in HCV transmission could be achieved through scale-up of DAAs and moderately effective behavioral interventions. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

An account of the real-life hepatitis C management in a single specialized viral hepatitis treatment centre in Egypt: results of treating 7042 patients with 7 different direct acting antiviral regimens.

PubMed

El Kassas, Mohamed; Alboraie, Mohamed; Omran, Dalia; Salaheldin, Mohamed; Wifi, Mohamed Naguib; ElBadry, Mohamed; El Tahan, Adel; Ezzat, Sameera; Moaz, Enass; Farid, Amir M; Omar, Heba; Abouelkhair, Mahmoud; Afify, Shimaa; Elsaeed, Kadry; Shazly, Yehia; Doss, Wahid; Esmat, Gamal

2018-05-14

A large Egyptian treatment program for HCV was launched in 2014 after the introduction of direct-acting antiviral agents (DAAs). This program depended mainly on establishing specialized independent centres for HCV treatment. These centres represent the major strengths in the Egyptian model of care, as they provide integrated care for HCV patients and have enabled Egypt to treat more than one million patients in 3 years. The New Cairo Viral Hepatitis Treatment Center (NCVHTC) is an example of these specialized centres. The Egyptian experience in the management of HCV was evaluated by analysing the data of real-life HCV management in the NCVHTC from 2014 to 2017. Results of different treatment regimens in addition to their strengths, limitations and areas for improvement are discussed in this report. A total of 7042 HCV patients have been evaluated for treatment in the NCVHTC. Among them, 5517 patients received treatment by seven different DAA regimens with excellent results. All regimens were highly effective at treating HCV in a real-life setting, apart from SOF/RBV, which was the least effective. A nationwide screening program and enhancing the follow-up of treated patients are the main missing pillars in the Egyptian model.

Safety of the 2D/3D direct-acting antiviral regimen in HCV-induced Child-Pugh A cirrhosis - A pooled analysis.

PubMed

Poordad, Fred; Nelson, David R; Feld, Jordan J; Fried, Michael W; Wedemeyer, Heiner; Larsen, Lois; Cohen, Daniel E; Cohen, Eric; Mobashery, Niloufar; Tatsch, Fernando; Foster, Graham R

2017-10-01

Chronic hepatitis C virus (HCV)-infected patients with cirrhosis are a high-priority population for treatment. To help inform the benefit-risk profile of the all-oral direct-acting antiviral (DAA) combination regimen of ombitasvir, paritaprevir, and ritonavir, with or without dasabuvir (OBV/PTV/r±DSV) in patients with Child-Pugh A cirrhosis, we undertook a comprehensive review of AbbVie-sponsored clinical trials enrolling patients with Child-Pugh A cirrhosis. Twelve phase II or III clinical trials of the 2-DAA regimen of OBV/PTV/r±ribavirin (RBV) or the 3-DAA regimen of OBV/PTV/r+DSV±RBV that included patients with Child-Pugh A cirrhosis were reviewed; patients who completed treatment by November 16, 2015 were included in a pooled, post hoc safety assessment. The number and percentage of patients with treatment-emergent adverse events (TEAEs), serious TEAEs, and TEAEs consistent with hepatic decompensation were reported. In 1,066 patients with Child-Pugh A cirrhosis, rates of serious TEAEs and TEAEs leading to study drug discontinuation were 5.3% (95% confidence interval [CI]: 4.1-6.8) and 2.2% (95% CI: 1.4-3.2), respectively. Thirteen patients (1.2%; 95% CI: 0.7-2.1) had a TEAE that was consistent with hepatic decompensation. The most frequent TEAEs consistent with hepatic decompensation were ascites (n=8), esophageal variceal hemorrhage (n=4), and hepatic encephalopathy (n=2). This pooled analysis in 1,066 HCV-infected patients with Child-Pugh A cirrhosis confirms the safety of OBV/PTV/r±DSV±RBV in this population. These results support the use of OBV/PTV/r±DSV±RBV in this high-priority population. Lay summary: This pooled safety analysis in 1,066 HCV-infected patients with compensated cirrhosis, receiving treatment with ombitasvir, paritaprevir, and ritonavir with or without dasabuvir, with or without ribavirin, shows that the rate of hepatic decompensation events was similar to previously reported rates in untreated patients. Copyright © 2017 European

Research priorities to achieve universal access to hepatitis C prevention, management and direct-acting antiviral treatment among people who inject drugs.

PubMed

Grebely, Jason; Bruneau, Julie; Lazarus, Jeffrey V; Dalgard, Olav; Bruggmann, Philip; Treloar, Carla; Hickman, Matthew; Hellard, Margaret; Roberts, Teri; Crooks, Levinia; Midgard, Håvard; Larney, Sarah; Degenhardt, Louisa; Alho, Hannu; Byrne, Jude; Dillon, John F; Feld, Jordan J; Foster, Graham; Goldberg, David; Lloyd, Andrew R; Reimer, Jens; Robaeys, Geert; Torrens, Marta; Wright, Nat; Maremmani, Icro; Norton, Brianna L; Litwin, Alain H; Dore, Gregory J

2017-09-01

Globally, it is estimated that 71.1 million people have chronic hepatitis C virus (HCV) infection, including an estimated 7.5 million people who have recently injected drugs (PWID). There is an additional large, but unquantified, burden among those PWID who have ceased injecting. The incidence of HCV infection among current PWID also remains high in many settings. Morbidity and mortality due to liver disease among PWID with HCV infection continues to increase, despite the advent of well-tolerated, simple interferon-free direct-acting antiviral (DAA) HCV regimens with cure rates >95%. As a result of this important clinical breakthrough, there is potential to reverse the rising burden of advanced liver disease with increased treatment and strive for HCV elimination among PWID. Unfortunately, there are many gaps in knowledge that represent barriers to effective prevention and management of HCV among PWID. The Kirby Institute, UNSW Sydney and the International Network on Hepatitis in Substance Users (INHSU) established an expert round table panel to assess current research gaps and establish future research priorities for the prevention and management of HCV among PWID. This round table consisted of a one-day workshop held on 6 September, 2016, in Oslo, Norway, prior to the International Symposium on Hepatitis in Substance Users (INHSU 2016). International experts in drug and alcohol, infectious diseases, and hepatology were brought together to discuss the available scientific evidence, gaps in research, and develop research priorities. Topics for discussion included the epidemiology of injecting drug use, HCV, and HIV among PWID, HCV prevention, HCV testing, linkage to HCV care and treatment, DAA treatment for HCV infection, and reinfection following successful treatment. This paper highlights the outcomes of the roundtable discussion focused on future research priorities for enhancing HCV prevention, testing, linkage to care and DAA treatment for PWID as we strive

Direct-acting antiviral therapy decreases hepatocellular carcinoma recurrence rate in cirrhotic patients with chronic hepatitis C.

PubMed

Virlogeux, Victor; Pradat, Pierre; Hartig-Lavie, Kerstin; Bailly, François; Maynard, Marianne; Ouziel, Guillaume; Poinsot, Domitille; Lebossé, Fanny; Ecochard, Marie; Radenne, Sylvie; Benmakhlouf, Samir; Koffi, Joseph; Lack, Philippe; Scholtes, Caroline; Uhres, Anne-Claire; Ducerf, Christian; Mabrut, Jean-Yves; Rode, Agnès; Levrero, Massimo; Combet, Christophe; Merle, Philippe; Zoulim, Fabien

2017-08-01

Arrival of direct-acting antiviral agents against hepatitis C virus with high-sustained virological response rates and very few side effects has drastically changed the management of hepatitis C virus infection. The impact of direct-acting antiviral exposure on hepatocellular carcinoma recurrence after a first remission in patients with advanced fibrosis remains to be clarified. 68 consecutive hepatitis C virus patients with a first hepatocellular carcinoma diagnosis and under remission, subsequently treated or not with a direct-acting antiviral combination, were included. Clinical, biological and virological data were collected at first hepatocellular carcinoma diagnosis, at remission and during the surveillance period. All patients were cirrhotic. Median age was 62 years and 76% of patients were male. Twenty-three patients (34%) were treated with direct-acting antivirals and 96% of them achieved sustained virological response. Median time between hepatocellular carcinoma remission and direct-acting antivirals initiation was 7.2 months (IQR: 3.6-13.5; range: 0.3-71.4) and median time between direct-acting antivirals start and hepatocellular carcinoma recurrence was 13.0 months (IQR: 9.2-19.6; range: 3.0-24.7). Recurrence rate was 1.7/100 person-months among treated patients vs 4.2/100 person-months among untreated patients (P=.008). In multivariate survival analysis, the hazard ratio for hepatocellular carcinoma recurrence after direct-acting antivirals exposure was 0.24 (95% confidence interval: 0.10-0.55; P<.001). Hepatocellular carcinoma recurrence rate was significantly lower among patients treated with direct-acting antivirals compared with untreated patients. Given the potential impact of our observation, large-scale prospective cohort studies are needed to confirm these results. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Impact of DAAs on liver transplantation: major effects on the evolution of indications and results. An ELITA study based on the ELTR registry.

PubMed

Belli, Luca Saverio; Perricone, Giovanni; Adam, Rene; Cortesi, Paolo A; Strazzabosco, Mario; Facchetti, Rita; Karam, Vincent; Salizzoni, Mauro; Andujar, Rafael Lopez; Fondevila, Costantino; De Simone, Paolo; Morelli, Cristina; Fabregat-Prous, Joan; Samuel, Didier; Agarwaal, Kosh; Gonzales, Enrique Moreno; Charco, Ramon; Zieniewicz, Krzysztof; De Carlis, Luciano; Duvoux, Christophe

2018-06-22

Direct-acting antiviral drugs (DAAs) have dramatically improved the outcome of patients with hepatitis C virus (HCV) infection including those with decompensated cirrhosis (DC). We analysed the evolution of indications and results of liver transplantation (LT) in the past 10 years in Europe, focusing on the changes induced by the advent of the DAA. This is a cohort study based on data from the European Liver Transplant Registry (ELTR). Data of adult LTs performed between January 2007 to June 2017 for HCV, hepatitis B virus (HBV), alcohol (ETOH) and non-alcoholic steatohepatitis (NASH) was analysed. The period was divided into different eras: interferon (IFN/RBV; 2007-2010), protease inhibitor (PI; 2011-2013) and second generation DAA (DAA; 2014-June 2017). Out of a total number of 60,527 LTs, 36,382 were performed in patients with HCV, HBV, ETOH and NASH. The percentage of LTs due to HCV-related liver disease varied significantly over time (p<0.0001), decreasing from 22.8% in IFN/RBV era to 17.4% in the DAA era, while those performed for NASH increased significantly (p<0.0001). In the DAA era, the percentage of LTs for HCV decreased significantly (p<0.0001) from 21.1% (first semester 2014) to 10.6% (first semester 2017). This decline was more evident in patients with DC (HCV-DC, -58.0%) than in those with HCC associated to HCV (HCV-HCC, -41.2%). Conversely, three-year survival of LT recipients with HCV related liver disease improved from 65.1% in the IFN/RBV era to 76.9% in the DAA era, being currently comparable to the survival of recipients with HBV infection (p=0.3807). In Europe, the number of LTs due to HCV infection is rapidly declining for both HCV-DC and HCV-HCC indications and post-LT survival has dramatically improved over the last three years. This is the first comprehensive study of the overall impact of DAA treatment for HCV on liver transplantation in Europe. After the advent of DAAs in 2014, a dramatic decline in the number of LT performed both in

Efficacy of Second Generation Direct-Acting Antiviral Agents for Treatment Naïve Hepatitis C Genotype 1: A Systematic Review and Network Meta-Analysis

PubMed Central

Sobhonslidsuk, Abhasnee; Thakkinstian, Ammarin; Teerawattananon, Yot

2015-01-01

Background The treatment of hepatitis C (HCV) infections has significantly changed in the past few years due to the introduction of direct-acting antiviral agents (DAAs). DAAs could improve the sustained virological response compared to pegylated interferon with ribavirin (PR). However, there has been no evidence from randomized controlled trials (RCTs) that directly compare the efficacy among the different regimens of DAAs. Aim Therefore, we performed a systematic review and network meta-analysis aiming to compare the treatment efficacy between different DAA regimens for treatment naïve HCV genotype 1. Methods Medline and Scopus were searched up to 25th May 2015. RCTs investigating the efficacy of second generation DAA regimens for treatment naïve HCV genotype 1 were eligible for the review. Due to the lower efficacy and more side effects of first generation DAAs, this review included only second generation DAAs approved by the US or EU Food and Drug Administration, that comprised of simeprevir (SMV), sofosbuvir (SOF), daclatasvir (DCV), ledipasvir (LDV), and paritaprevir/ritonavir/ombitasvir plus dasabuvir (PrOD). Primary outcomes were sustained virological response at weeks 12 (SVR12) and 24 (SVR24) after the end of treatment and adverse drug events (i.e. serious adverse events, anemia, and fatigue). Efficacy of all treatment regimens were compared by applying a multivariate random effect meta-analysis. Incidence rates of SVR12 and SVR24, and adverse drug events of each treatment regimen were pooled using ‘pmeta’ command in STATA program. Results Overall, 869 studies were reviewed and 16 studies were eligible for this study. Compared with the PR regimen, SOF plus PR, SMV plus PR, and DVC plus PR regimens yielded significantly higher probability of having SVR24 with pooled risk ratios (RR) of 1.98 (95% CI 1.24, 3.14), 1.46 (95% CI: 1.22, 1.75), and 1.68 (95% CI: 1.14, 2.46), respectively. Pooled incidence rates of SVR12 and SVR24 in all treatment regimens

Comprehensive Screening for Naturally Occurring Hepatitis C Virus Resistance to Direct-Acting Antivirals in the NS3, NS5A, and NS5B Genes in Worldwide Isolates of Viral Genotypes 1 to 6.

PubMed

Patiño-Galindo, Juan Ángel; Salvatierra, Karina; González-Candelas, Fernando; López-Labrador, F Xavier

2016-04-01

There is no comprehensive study available on the natural hepatitis C virus (HCV) polymorphism in sites associated with resistance including all viral genotypes which may present variable susceptibilities to particular direct-acting antivirals (DAAs). This study aimed to analyze the frequencies, genetic barriers, and evolutionary histories of naturally occurring resistance-associated variants (RAVs) in the six main HCV genotypes. A comprehensive analysis of up to 103 RAVs was performed in 2,901, 2,216, and 1,344 HCV isolates for the NS3, NS5A, and NS5B genes, respectively. We report significant intergenotypic differences in the frequencies of natural RAVs for these three HCV genes. In addition, we found a low genetic barrier for the generation of new RAVs, irrespective of the viral genotype. Furthermore, in 1,126 HCV genomes, including sequences spanning the three genes, haplotype analysis revealed a remarkably high frequency of viruses carrying more than one natural RAV to DAAs (53% of HCV-1a, 28.5% of HCV-1b, 67.1% of HCV-6, and 100% of genotype 2, 3, 4, and 5 haplotypes). With the exception of HCV-1a, the most prevalent haplotypes showed RAVs in at least two different viral genes. Finally, evolutionary analyses revealed that, while most natural RAVs appeared recently, others have been efficiently transmitted over time and cluster in well-supported clades. In summary, and despite the observed high efficacy of DAA-based regimens, we show that naturally occurring RAVs are common in all HCV genotypes and that there is an overall low genetic barrier for the selection of resistance mutations. There is a need for natural DAA resistance profiling specific for each HCV genotype. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Defining the Collision Avoidance Region for DAA Systems

NASA Technical Reports Server (NTRS)

Thipphavong, David; Cone, Andrew; Park, Chunki; Lee, Seung Man; Santiago, Confesor

2016-01-01

Unmanned aircraft systems (UAS) will be required to equip with a detect-­-and-­-avoid (DAA) system in order to satisfy the federal aviation regulations to maintain well clear of other aircraft, some of which may be equipped with a Traffic Collision Avoidance System (TCAS) to mitigate the possibility of mid-­-air collisions. As such, the minimum operational performance standards (MOPS) for UAS DAA systems are being designed with TCAS interoperability in mind by a group of industry, government, and academic institutions named RTCA Special Committee-228 (SC-228). This document will discuss the development of the spatial-­-temporal volume known as the collision avoidance region in which the DAA system is not allowed to provide vertical guidance to maintain or regain DAA well clear that could conflict with resolution advisories (RAs) issued by the intruder aircraft's TCAS system. Three collision avoidance region definition candidates were developed based on the existing TCAS RA and DAA alerting definitions. They were evaluated against each other in terms of their interoperability with TCAS RAs and DAA alerts in an unmitigated factorial encounter analysis of 1.3 million simulated pairs.

The elderly and direct antiviral agents: Constraint or challenge?

PubMed

Fabrizio, Claudia; Saracino, Annalisa; Scudeller, Luigia; Milano, Eugenio; Dell'Acqua, Raffaele; Bruno, Giuseppe; Lo Caputo, Sergio; Monno, Laura; Milella, Michele; Angarano, Gioacchino

2017-09-01

Direct antiviral agents (DAAs) for chronic hepatitis C showed great effectiveness and good safety profile. So far, few data are available about their use in elderly subjects. To assess management, safety and outcome of DAAs treatments in the elderly. This retrospective, single-centre study enrolled all patients aged ≥65 years, compared by age (group A: 65-74 years, group B: ≥75 years), who completed DAAs between February 2015-November 2016. Variables potentially associated to adverse events (AEs) were analyzed. Sustained virological response (SVR) was evaluated at 12-weeks follow-up. DAAs were administered to 221 patients aged ≥65 years (males: 112; group A: 130, group B: 91). Prescribed regimens were: sofosbuvir-based: 44 patients (19.9%), simeprevir-based: 25 (15%), ledipasvir-based: 49 (22.2%), daclatasvir-based: 12 (5.4%), paritaprevir/ritonavir+ombitasvir±dasabuvir: 91 (41.2%). Ribavirin was used in 121 patients. In 58 subjects co-medications were adjusted due to drug interactions. At least one AE occurred in 130 patients, including 13 SAEs, mainly in older subjects (p=0.04). Female sex (p=0.04), liver stiffness (p=0.023), use of simeprevir (p=0.03) and ribavirin (p=0.009) were associated with AEs. SVR-12 was achieved in 96,9% of subjects. A careful baseline evaluation and a strict monitoring allow to optimise management and outcome of DAAs in elderly. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Modeling how reversal of immune exhaustion elicits cure of chronic hepatitis C after the end of treatment with direct-acting antiviral agents.

PubMed

Baral, Subhasish; Roy, Rahul; Dixit, Narendra M

2018-05-09

A fraction of chronic hepatitis C patients treated with direct-acting antivirals (DAAs) achieved sustained virological responses (SVR), or cure, despite having detectable viremia at the end of treatment (EOT). This observation, termed EOT + /SVR, remains puzzling and precludes rational optimization of treatment durations. One hypothesis to explain EOT + /SVR, the immunologic hypothesis, argues that the viral decline induced by DAAs during treatment reverses the exhaustion of cytotoxic T lymphocytes (CTLs), which then clear the infection after treatment. Whether the hypothesis is consistent with data of viral load changes in patients who experienced EOT + /SVR is unknown. Here, we constructed a mathematical model of viral kinetics incorporating the immunologic hypothesis and compared its predictions with patient data. We found the predictions to be in quantitative agreement with patient data. Using the model, we unraveled an underlying bistability that gives rise to EOT + /SVR and presents a new avenue to optimize treatment durations. Infected cells trigger both activation and exhaustion of CTLs. CTLs in turn kill infected cells. Due to these competing interactions, two stable steady states, chronic infection and viral clearance, emerge, separated by an unstable steady state with intermediate viremia. When treatment during chronic infection drives viremia sufficiently below the unstable state, spontaneous viral clearance results post-treatment, marking EOT + /SVR. The duration to achieve this desired reduction in viremia defines the minimum treatment duration required for ensuring SVR, which our model can quantify. Estimating parameters defining the CTL response of individuals to HCV infection would enable the application of our model to personalize treatment durations. © 2018 The Authors Immunology & Cell Biology published by John Wiley & Sons Australia, Ltd on behalf of Australasian Society for Immunology Inc.

Impact of Direct Acting Antiviral Therapy for Treatment of Hepatitis C Genotypes 1, 3 and 4: A Real Life Experience from India.

PubMed

Mehta, Varun; Mahajan, Ramit; Midha, Vandana; Narang, Vikram; Kaur, Kirandeep; Singh, Arshdeep; Malhotra, Anand; Parvez, Aslam; Sood, Ajit

2018-03-01

To assess impact of Direct Acting Antiviral (DAA) therapies for treatment of Hepatitis C Virus (HCV) genotypes 1, 3 and 4 in a real-world cohort from India. Adults with chronic HCV infection treated with Sofosbuvir (SOF) and Ledipasvir (LDV) (genotypes 1 and 4) or SOF and Daclatasvir (DCV) (genotype 3), with or without Ribavirin (RBV) between December 2015 and December 2016 were included. The primary endpoint was Sustained Virological Response at Post-treatment Week 12 (SVR12). Of the 648 patients, 181 received SOF/LDV (65 with RBV) and 467 received SOF/DCV (135 with RBV). Most patients were males (65.4%), aged 41-60 years (49.4%) and treatment-naïve (92.6%). Genotype 3 (72.1%) was most common, followed by genotypes 1 (22.4%) and 4 (5.6%). Forty two percent patients ( n  = 271) had cirrhosis (112 patients were decompensated). SVR12 (modified intention-to-treat) was achieved by 98.1% of patients (512/522) (100% in genotypes 1 and 4, and 97.3% (362/372) in genotype 3). On intention to treat analysis, SVR12 was 88.1% (512/581) [genotype 1-96.8% (121/125), genotype 3-85.2%, genotype 4-93.5% (29/31)]. Seventy patients had treatment failure (non response in 6, virological breakthrough in 2, 10 patients relapsed, 2 died and 50 were lost to follow up). High SVR was observed regardless of HCV genotype, presence of cirrhosis or past history of treatment. No major adverse events warranting discontinuation of treatment were noted. DAA therapy for HCV genotypes 1, 3 and 4 achieves high SVR rates in all patients, including those with cirrhosis and previous non-responders.

Week 4 response predicts sustained virological response to all-oral direct-acting antiviral-based therapy in cirrhotic patients with hepatitis C virus genotype 3 infection.

PubMed

Pineda, J A; Morano-Amado, L E; Granados, R; Macías, J; Téllez, F; García-Deltoro, M; Ríos, M J; Collado, A; Delgado-Fernández, M; Suárez-Santamaría, M; Serrano, M; Miralles-Álvarez, C; Neukam, K

2017-06-01

The aim of this study was to determine the predictive capacity of response at treatment week (TW) 4 for the achievement of sustained virological response 12 weeks after the scheduled end of therapy date (SVR 12 ) to treatment against hepatitis C virus (HCV) genotype 3 (GT3) infection with all-oral direct-acting antiviral (DAA) -based regimens. From a prospective multicohort study, HCV GT3-infected patients who completed a course of currently recommended DAA-based therapy at 33 Spanish hospitals and who had reached the SVR 12 evaluation time-point were selected. TW4 HCV-RNA levels were categorized as target-not-detected (TND), below the lower limit of quantification (LLOQ TD ) and ≥LLOQ. A total of 123 patients were included, 86 (70%) received sofosbuvir/ daclatasvir±ribavirin, 27 (22%) received sofosbuvir/ ledipasvir/ ribavirin and 10 (8.1%) received sofosbuvir/ ribavirin, respectively. In all, 114 (92.7%) of the 123 patients presented SVR 12 in an on-treatment approach, but nine (7.3%) patients relapsed, all of them had presented cirrhosis at baseline. In those who achieved TND, LLOQ TD and ≥LLOQ, SVR 12 was observed in 81/83 (98%; 95% CI 91.5%-99.7%), 24/28 (85.7%; 95% CI 67.3%-96%) and 9/12 (75%; 95% CI 42.8%-94.5%), respectively; p (linear association) 0.001. Corresponding numbers for subjects with cirrhosis were: 52/54 (96.3%; 95% CI 87.3%-95.5%), 14/18 (77.8%; 95% CI 52.4%-93.6%) and 7/10 (70%; 95% CI 34.8%-93.3%); p 0.004. TW4-response indicates the probability of achieving SVR 12 to currently used DAA-based therapy in HCV genotype 3-infected individuals with cirrhosis. This finding may be useful to tailor treatment strategy in this setting. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Improvement of liver stiffness measurement, acoustic radiation force impulse measurements, and noninvasive fibrosis markers after direct-acting antivirals for hepatitis C virus G4 recurrence post living donor liver transplantation: Egyptian cohort.

PubMed

Alem, Shereen Abdel; Said, Mohamed; Anwar, Ismail; Abdellatif, Zeinab; Elbaz, Tamer; Eletreby, Rasha; AbouElKhair, Mahmoud; El-Serafy, Magdy; Mogawer, Sherif; El-Amir, Mona; El-Shazly, Mostafa; Hosny, Adel; Yosry, Ayman

2018-05-02

Progression of recurrent hepatitis C is accelerated in liver transplant (LT) recipients. Direct-acting antivirals (DAAs) have recently emerged as a promising therapeutic regimen for the treatment of hepatitis C virus infection. Rates of sustained virological response (SVR) have drastically improved since the introduction of DAAs. The aim is to elucidate the changes in liver stiffness measurement (LSM) by transient elastography (TE) as well as acoustic radiation force impulse (ARFI) elastography and fibrosis scores after DAA treatment in LT recipients with hepatitis C virus recurrence. A single-center, prospective study including 58 LT recipients with hepatitis C recurrence who received different sofosbuvir-based treatment regimens. Transient elastography and ARFI elastography values were recorded as well as fibrosis 4 score (FIB-4) and aspartate aminotransferase-to-platelet ratio index were calculated at baseline and SVR at week 24 (SVR24). The outcome was improvement in LSM and at least a 20% decrease in LSM at SVR24 compared with baseline. The sustained virological response was 98.1%. There was improvement of platelet counts, alanine aminotransferase, and aspartate aminotransferase, which in turn caused improvement in fibrosis scores at SVR24. LSM by TE and ARFI elastography decreased from the baseline median value of 6.3 kPa (interquartile range [IQR]; 4.6 to 8.8 kPa) and 1.28 m/s (IQR; 1.07 to 1.53 m/s) to an SVR24 median value of 6.2 kPa (IQR; 4.85 to 8.9 kPa) and 1.12 (IQR; 0.97 to 1.30 m/s), respectively. Logistic regression analysis showed that baseline viral load was the only significant predictor of improvement in LS after DAA therapy at SVR24. Sofosbuvir-based treatment resulted in an early improvement in parameters of liver fibrosis in post-LT patients with hepatitis C recurrence. © 2018 Wiley Periodicals, Inc.

Addressing the Challenges of Hepatitis C Virus Resistance and Treatment Failure.

PubMed

Colpitts, Che C; Baumert, Thomas F

2016-08-16

Chronic hepatitis C is a major cause of chronic liver disease, including liver cirrhosis and hepatocellular carcinoma. The development of direct-acting antivirals (DAAs) revolutionized hepatitis C virus (HCV) treatment by offering genuine prospects for the first comprehensive cure of a chronic viral infection in humans. While antiviral resistance is a significant limitation for interferon-based therapies, resistance and treatment failure still appear to be present in a small fraction of patients even in state-of-the-art DAA combination therapies. Therefore, treatment failure and resistance still remain a clinical challenge for the management of patients not responding to DAAs. In this special issue of Viruses on HCV drug resistance, mechanisms of antiviral resistance for different classes of antiviral drugs are described. Furthermore, the detection and monitoring of resistance in clinical practice, the clinical impact of resistance in different patient groups and strategies to prevent and address resistance and treatment failure using complementary antiviral strategies are reviewed.

Mechanisms of Hepatitis C Viral Resistance to Direct Acting Antivirals.

PubMed

Ahmed, Asma; Felmlee, Daniel J

2015-12-18

There has been a remarkable transformation in the treatment of chronic hepatitis C in recent years with the development of direct acting antiviral agents targeting virus encoded proteins important for viral replication including NS3/4A, NS5A and NS5B. These agents have shown high sustained viral response (SVR) rates of more than 90% in phase 2 and phase 3 clinical trials; however, this is slightly lower in real-life cohorts. Hepatitis C virus resistant variants are seen in most patients who do not achieve SVR due to selection and outgrowth of resistant hepatitis C virus variants within a given host. These resistance associated mutations depend on the class of direct-acting antiviral drugs used and also vary between hepatitis C virus genotypes and subtypes. The understanding of these mutations has a clear clinical implication in terms of choice and combination of drugs used. In this review, we describe mechanism of action of currently available drugs and summarize clinically relevant resistance data.

Real-world outcomes of unrestricted direct-acting antiviral treatment for hepatitis C in Australia: The South Australian statewide experience.

PubMed

Haridy, James; Wigg, Alan; Muller, Kate; Ramachandran, Jeyamani; Tilley, Emma; Waddell, Victoria; Gordon, David; Shaw, David; Huynh, Dep; Stewart, Jeffrey; Nelson, Renjy; Warner, Morgyn; Boyd, Mark; Chinnaratha, Mohamed A; Harding, Damian; Ralton, Lucy; Colman, Anton; Liew, Danny; Iyngkaran, Guru; Tse, Edmund

2018-06-11

In March 2016, the Australian government offered unrestricted access to direct-acting antiviral (DAA) therapy for chronic hepatitis C (HCV) to the entire population. This included prescription by any medical practitioner in consultation with specialists until sufficient experience was attained. We sought to determine the outcomes and experience over the first twelve-months for the entire state of South Australia. We performed a prospective, observational study following outcomes of all treatments associated with the state's four main tertiary centres. 1909 subjects initiating DAA therapy were included, representing an estimated 90% of all treatments in the state. Overall, SVR12 was 80.4% in all subjects intended for treatment and 95.7% in those completing treatment and follow-up. 14.2% were lost to follow-up (LTFU) and did not complete SVR12 testing. LTFU was independently associated with community treatment via remote consultation (OR 1.50, 95% CI 1.04-2.18, p=0.03), prison-based treatment (OR 2.02, 95% CI 1.08-3.79, p=0.03) and younger age (OR 0.98, 95% CI 0.97-0.99, p=0.05). Of the 1534 subjects completing treatment and follow-up, decreased likelihood of SVR12 was associated with genotype 2 (OR 0.23,95% CI 0.07-0.74, p=0.01) and genotype 3 (OR 0.23 95% CI 0.12-0.43, p=<0.01). A significant decrease in treatment initiation was observed over the twelve-month period in conjunction with a shift from hospital to community-based treatment. Our findings support the high responses observed in clinical trials, however a significant gap exists in SVR12 in our real-world cohort due to LTFU. A declining treatment initiation rate and shift to community-based treatment highlights the need to explore additional strategies to identify, treat and follow-up remaining patients in order to achieve elimination targets. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Hepatitis C Virus and Interferon-Free Antiviral Therapeutics Revolution: Implications for Pakistan.

PubMed

Afzal, Muhammad Sohail

2017-05-01

Hepatitis C virus (HCV) is a major health concern worldwide as a leading cause of liver-related mortalities and morbidities. Pakistan ranks second among countries with endemic HCV infection; ∼11 million cases are reported so far. HCV burden is continuously rising in Pakistan, mainly because of unsafe blood transfusions, surgical procedures, dental procedures, untrained clinicians, reuse of syringes, barbers, and ear/nose piercing tools. Lack of awareness about HCV transmission routes among the general and high-risk population is a major hurdle in disease management. HCV prevalence in the general population and healthy blood donors ranges from 3.13% to 23.83% and from 1.05% to 20.8%, respectively; whereas in the high-risk groups, HCV prevalence is up to 66%. Genotype 3 is most prevalent in Pakistan followed by genotypes 1 and 2 along with an alarming number of untypable viral genotypes in the local community. Mainly interferon-based antiviral regimens are used in Pakistan and are quite effective, because the major prevalent genotype (genotype 3) showed the best sustained virological response (SVR) with it. But a large number of individuals did not show SVR either because of infection with nonresponder genotypes or because of side effects. Due to these reasons, there was a need for interferon-free direct acting antivirals (DAAs). Recently, Sovaldi (Sofosbuvir: NS5B inhibitor) is approved on a heavy discounted rate for Pakistan; it is currently in effective use and showed good SVR. Sovaldi plus ribavirin is used alone or along with interferon to treat different viral genotypes. Sovaldi will be the future treatment regime for Pakistan, because genotype 2 and genotype 3 infected individuals achieve the best SVR with it. For the treatment of other prevalent viral genotypes, approval of some other DAAs such as Ledipasvir on discounted price is required for better disease management.

The drug-drug interaction potential of antiviral agents for the treatment of chronic hepatitis C infection.

PubMed

Garrison, Kimberly L; German, Polina; Mogalian, Erik; Mathias, Anita

2018-04-25

Several safe and highly-effective directly-acting antiviral drugs for chronic hepatitis C virus (HCV) have been developed and greatly increase the number of treatment options available to successfully treat HCV infection. However, as treatment regimens contain at least two drugs (e.g., sofosbuvir with daclatasvir, simeprevir, ledipasvir, or velpatasvir; elbasvir and grazoprevir) and up to five drugs (ombitasvir/paritaprevir/ritonavir+dasabuvir+ribavirin), the potential for drug-drug interactions (DDI) becomes an important consideration for HCV-infected individuals with comorbidities that require concomitant medications, such as HIV/HCV co-infection or immunosuppression following liver transplantation. This review details the pharmacokinetics and DDI potential of approved DAAs for the treatment of HCV infection. The American Society for Pharmacology and Experimental Therapeutics.

In Vitro Antiviral Activity and Resistance Profile Characterization of the Hepatitis C Virus NS5A Inhibitor Ledipasvir

PubMed Central

Tian, Yang; Doehle, Brian; Peng, Betty; Corsa, Amoreena; Lee, Yu-Jen; Gong, Ruoyu; Yu, Mei; Han, Bin; Xu, Simin; Dvory-Sobol, Hadas; Perron, Michel; Xu, Yili; Mo, Hongmei; Pagratis, Nikos; Link, John O.; Delaney, William

2016-01-01

Ledipasvir (LDV; GS-5885), a component of Harvoni (a fixed-dose combination of LDV with sofosbuvir [SOF]), is approved to treat chronic hepatitis C virus (HCV) infection. Here, we report key preclinical antiviral properties of LDV, including in vitro potency, in vitro resistance profile, and activity in combination with other anti-HCV agents. LDV has picomolar antiviral activity against genotype 1a and genotype 1b replicons with 50% effective concentration (EC50) values of 0.031 nM and 0.004 nM, respectively. LDV is also active against HCV genotypes 4a, 4d, 5a, and 6a with EC50 values of 0.11 to 1.1 nM. LDV has relatively less in vitro antiviral activity against genotypes 2a, 2b, 3a, and 6e, with EC50 values of 16 to 530 nM. In vitro resistance selection with LDV identified the single Y93H and Q30E resistance-associated variants (RAVs) in the NS5A gene; these RAVs were also observed in patients after a 3-day monotherapy treatment. In vitro antiviral combination studies indicate that LDV has additive to moderately synergistic antiviral activity when combined with other classes of HCV direct-acting antiviral (DAA) agents, including NS3/4A protease inhibitors and the nucleotide NS5B polymerase inhibitor SOF. Furthermore, LDV is active against known NS3 protease and NS5B polymerase inhibitor RAVs with EC50 values equivalent to those for the wild type. PMID:26824950

In Vitro Antiviral Activity and Resistance Profile Characterization of the Hepatitis C Virus NS5A Inhibitor Ledipasvir.

PubMed

Cheng, Guofeng; Tian, Yang; Doehle, Brian; Peng, Betty; Corsa, Amoreena; Lee, Yu-Jen; Gong, Ruoyu; Yu, Mei; Han, Bin; Xu, Simin; Dvory-Sobol, Hadas; Perron, Michel; Xu, Yili; Mo, Hongmei; Pagratis, Nikos; Link, John O; Delaney, William

2016-01-11

Ledipasvir (LDV; GS-5885), a component of Harvoni (a fixed-dose combination of LDV with sofosbuvir [SOF]), is approved to treat chronic hepatitis C virus (HCV) infection. Here, we report key preclinical antiviral properties of LDV, including in vitro potency, in vitro resistance profile, and activity in combination with other anti-HCV agents. LDV has picomolar antiviral activity against genotype 1a and genotype 1b replicons with 50% effective concentration (EC50) values of 0.031 nM and 0.004 nM, respectively. LDV is also active against HCV genotypes 4a, 4d, 5a, and 6a with EC50 values of 0.11 to 1.1 nM. LDV has relatively less in vitro antiviral activity against genotypes 2a, 2b, 3a, and 6e, with EC50 values of 16 to 530 nM. In vitro resistance selection with LDV identified the single Y93H and Q30E resistance-associated variants (RAVs) in the NS5A gene; these RAVs were also observed in patients after a 3-day monotherapy treatment. In vitro antiviral combination studies indicate that LDV has additive to moderately synergistic antiviral activity when combined with other classes of HCV direct-acting antiviral (DAA) agents, including NS3/4A protease inhibitors and the nucleotide NS5B polymerase inhibitor SOF. Furthermore, LDV is active against known NS3 protease and NS5B polymerase inhibitor RAVs with EC50 values equivalent to those for the wild type. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

"Waiting for DAAs": A retrospective chart review of patients with untreated hepatitis C in Rwanda.

PubMed

Gupta, Neil; Kabahizi, Jules; Mukabatsinda, Constance; Walker, Timothy David; Musabeyezu, Emmanuel; Kiromera, Athanase; Van Nuil, Jennifer Ilo; Steiner, Kevin; Mukherjee, Joia; Nsanzimana, Sabin; Mbituyumuremyi, Aimable

2017-01-01

Access to treatment for hepatitis C virus (HCV) in sub-Saharan Africa is extremely limited. With the advent of direct acting antivirals (DAAs), highly effective and easy-to-deliver oral regimens are now available on the global market. This study was conducted to understand the background and characteristics of a national cohort of patients with HCV infection enrolled in care and awaiting therapy with DAAs. We conducted a retrospective chart review of all adult patients with confirmed HCV infection who were currently enrolled in care and treatment at the four existing hepatitis referral centers in Rwanda. Patient charts at these centers were reviewed, and routinely collected data were recorded and analyzed. Overall, 253 patients were identified; median age was 56 years (IQR: 43, 65), and 149 (58.9%) were female. Median viral load was 688,736 IU/ml and 96.7% were HCV genotype 4. As classified by FIB-4 score, 64.8% of the patients had moderate to severe fibrosis. Fibrosis stage was associated with age (OR 1.12, CI 1.09-1.17), but not with time since diagnosis, gender, treatment center, or type of insurance. There was a low frequency of documented co-morbid conditions, including hypertension, diabetes, HIV, and hepatitis B virus. Compared to an estimated 55,000 patients eligible for HCV treatment in Rwanda, this study identified only 253 patients currently diagnosed and engaged in care, highlighting an immense treatment gap in HCV, likely due to the lack of accessible and affordable screening, diagnostic, and treatment modalities. The patients that were enrolled in care had a disproportionately advanced fibrosis stage, possibly indicating late presentation to care or lack of treatment options. In the context of newly available and effective treatment options, this study supports the overall need to accelerate access to HCV screening, diagnostics, and care and treatment services in resource-limited settings in sub-Saharan Africa.

Software modifications to the Demonstration Advanced Avionics Systems (DAAS)

NASA Technical Reports Server (NTRS)

Nedell, B. F.; Hardy, G. H.

1984-01-01

Critical information required for the design of integrated avionics suitable for generation aviation is applied towards software modifications for the Demonstration Advanced Avionics System (DAAS). The program emphasizes the use of data busing, distributed microprocessors, shared electronic displays and data entry devices, and improved functional capability. A demonstration advanced avionics system (DAAS) is designed, built, and flight tested in a Cessna 402, twin engine, general aviation aircraft. Software modifications are made to DAAS at Ames concurrent with the flight test program. The changes are the result of the experience obtained with the system at Ames, and the comments of the pilots who evaluated the system.

Antiviral therapies for chronic hepatitis C virus infection with cirrhosis

PubMed Central

Nakamoto, Shingo; Kanda, Tatsuo; Shirasawa, Hiroshi; Yokosuka, Osamu

2015-01-01

Patients who are infected with hepatitis C virus (HCV) and also have advanced fibrosis or cirrhosis have been recognized as “difficult-to-treat” patients during an era when peginterferon and ribavirin combination therapy is the standard of care. Recent guidelines have clearly stated that treatment should be prioritized in this population to prevent complications such as decompensation and hepatocellular carcinoma. Recent advances in the treatment of chronic hepatitis C have been achieved through the development of direct-acting antiviral agents (DAAs). Boceprevir and telaprevir are first-generation DAAs that inhibit the HCV NS3/4A protease. Boceprevir or telaprevir, in combination with peginterferon and ribavirin, improved the sustained virological response rates compared with peginterferon and ribavirin alone and were tolerated in patients with HCV genotype 1 infection without cirrhosis or compensated cirrhosis. However, the efficacy is lower especially in prior non-responders with or without cirrhosis. Furthermore, a high incidence of adverse events was observed in patients with advanced liver disease, including cirrhosis, in real-life settings. Current guidelines in the United States and in some European countries no longer recommend these regimens for the treatment of HCV. Next-generation DAAs include second-generation HCV NS3/4A protease inhibitors, HCV NS5A inhibitors and HCV NS5B inhibitors, which have a high efficacy and a lower toxicity. These drugs are used in interferon-free or in interferon-based regimens with or without ribavirin in combination with different classes of DAAs. Interferon-based regimens, such as simeprevir in combination with peginterferon and ribavirin, are well tolerated and are highly effective especially in treatment-naïve patients and in patients who received treatment but who relapsed. The efficacy is less pronounced in null-responders and in patients with cirrhosis. Interferon-free regimens in combination with ribavirin and

SC-228 Inclusion of DAA Warning Alert for TCAS Interoperability

NASA Technical Reports Server (NTRS)

Fern, Lisa

2016-01-01

alerting system is to provide critical timing information to the pilot about the potential for a loss of well clear with another aircraft. This is done by employing both temporal and spatial thresholds that indicate to the pilot the likelihood and imminence of a loss of well clear. The design of the DAA alerting thresholds is a balancing act between eliciting the desired pilot response in real loss of well clear threat events and reducing excessive, unnecessary, and/or uncoordinated UAS maneuvering within the air traffic environment; larger thresholds, both spatially and temporally, may increase the likelihood of a pilot avoiding a loss of well clear, but it can also increase the frequency of maneuvering - especially in cases where a maneuver is not actually needed to maintain well clear. A series of human in the loop (HITL) simulations have been conducted as part of NASA's Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) project. The purpose of these HITLs has been to provide empirical results in order to inform development of the minimum human-machine interface requirements for the DAA system. This white paper will present those results which provide evidence of a human performance benefit (in terms of response times and ability to remain well clear of other aircraft) of the DAA warning alert both with and without a collision avoidance system on board the aircraft.

Hepatitis C Virus: Viral Quasispecies and Genotypes.

PubMed

Tsukiyama-Kohara, Kyoko; Kohara, Michinori

2017-12-22

Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance.

Impact of hepatitis C virus genotype-4 eradication following direct acting antivirals on liver stiffness measurement.

PubMed

Tag-Adeen, Mohammed; Sabra, Ahlam Mohamed; Akazawa, Yuko; Ohnita, Ken; Nakao, Kazuhiko

2017-01-01

Liver fibrosis is the most important prognostic factor in chronic hepatitis C virus (HCV) patients, and Egypt shows the highest worldwide HCV prevalence with genotype-4 pre-dominance. The aim of this study was to investigate the degree of liver stiffness measurement (LSM) improvement after successful HCV eradication. The study included 84 chronic HCV Egyptian patients, and was conducted at Qena University Hospital from November 1, 2015 till October 31, 2016. LSM was obtained by FibroScan® before starting direct acting antiviral (DAA) treatment and after achieving sustained virologic response-24 (SVR-24). Based on baseline LSM, patients were stratified into F0-F1, F2, F3 and F4 groups (METAVIR). LSM and laboratory data after achieving SVR-24 was compared with that before starting therapy in each fibrosis group (F0-F4), p -value <0.05 was statistically significant. Following DAA treatment, 80 patients achieved SVR-24; of these, 50 were males (62.5%), mean age: 54.2±7.6 years, and mean body mass index: 28.6±2.2 kg/m 2 . Mean baseline LSM dropped from 15.6±10.8 to 12.1±8.7 kPa post-SVR; the maximum change of -5.8 occurred in F4 versus -2.79, -1.28 and +0.08 in F3, F2 and F0-F1 respectively ( p <0.0001). At baseline, 41 patients were in the F4 group; only 16 (39%) regressed to non-cirrhotic range (<12.5 kPa), while 25 (61%) were still cirrhotic despite achieving SVR-24 ( p <0.0001). Patients who achieved LSM improvement (n=64) have had significantly higher baseline aspartate transferase (AST) and alanine transaminase (ALT). Also, those patients showed significant improvement in AST, AST/platelets ratio index (APRI) and fibrosis-4 index (Fib-4) after achieving SVR; 91% showed AST improvement ( p =0.01) and APRI improvement ( p =0.01) and 81% showed Fib-4 improvement ( p =0.04). Females, diabetics, patients with S3 steatosis and patients older than 50 years showed less LSM improvements than their counterparts. Baseline LSM ≥9 kPa, bilirubin ≥1 mg/dl, ALT ≥36 U

Sofosbuvir treatment and hepatitis C virus infection

PubMed Central

Nakamura, Masato; Kanda, Tatsuo; Haga, Yuki; Sasaki, Reina; Wu, Shuang; Nakamoto, Shingo; Yasui, Shin; Arai, Makoto; Imazeki, Fumio; Yokosuka, Osamu

2016-01-01

Hepatitis C virus (HCV) infection is a serious problem worldwide. The use of interferon-based therapy has made HCV eradication challenging. The recent appearance of direct-acting antiviral agents (DAAs) has changed HCV therapy. Combining the use of DAAs with peginterferon and ribavirin has improved treatment efficacy. Furthermore, the combination of different orally administered DAAs has enabled interferon-free therapy with much higher efficacy and safety. In particular, sofosbuvir, a nucleotide-based NS5B inhibitor, prevents HCV RNA synthesis by acting as a “chain terminator”. Treatment with sofosbuvir has attained an extremely high rate of sustained virologic response. The current review summarizes the efficacy and safety of sofosbuvir therapy. PMID:26839641

AIAA Aviation UAS DAA Demonstration-Mini HITL Week 2 Stats

NASA Technical Reports Server (NTRS)

Fern, Lisa Carolynn; Murphy, James R.; Jovic, Srboljub

2016-01-01

The UAS-NAS Project demo will showcase recent research efforts to ensure the interoperability between proposed UAS detect and avoid (DAA) human machine interface requirements (developed within RTCA SC-228) and existing collision avoidance displays. Attendees will be able to view the current state of the art of the DAA pilot traffic, alerting and guidance displays integrated with Traffic advisory and Collision Avoidance (TCAS) II in the UAS-NAS Project's research UAS ground control station (developed in partnership with the Air Force Research Laboratory). In addition, attendees will have the opportunity to interact with the research UAS ground control station and "fly" encounters, using the DAA and TCAS II displays to avoid simulated aircraft. The display of the advisories will be hosted on a laptop with an external 30" monitor, running the Vigilant Spririt system. DAA advisories will be generated by the JADEM software tool, connected to the system via the LVC Gateway. A repeater of the primary flight display will be shown on a 55" tv/monitor mounted on a stand at the back of the booth to show the pilot interaction to the passersby.

Drug-Drug Interaction between the Direct-Acting Antiviral Regimen of Ombitasvir-Paritaprevir-Ritonavir plus Dasabuvir and the HIV Antiretroviral Agent Dolutegravir or Abacavir plus Lamivudine.

PubMed

Khatri, Amit; Trinh, Roger; Zhao, Weihan; Podsadecki, Thomas; Menon, Rajeev

2016-10-01

The direct-acting antiviral regimen of 25 mg ombitasvir-150 mg paritaprevir-100 mg ritonavir once daily (QD) plus 250 mg dasabuvir twice daily (BID) is approved for the treatment of hepatitis C virus genotype 1 infection, including patients coinfected with human immunodeficiency virus. This study was performed to evaluate the pharmacokinetic, safety, and tolerability effects of coadministering the regimen of 3 direct-acting antivirals with two antiretroviral therapies (dolutegravir or abacavir plus lamivudine). Healthy volunteers (n = 24) enrolled in this phase I, single-center, open-label, multiple-dose study received 50 mg dolutegravir QD for 7 days or 300 mg abacavir plus 300 mg lamivudine QD for 4 days, the 3-direct-acting-antiviral regimen for 14 days, followed by the 3-direct-acting-antiviral regimen with dolutegravir or abacavir plus lamivudine for 10 days. Pharmacokinetic parameters were calculated to compare combination therapy with 3-direct-acting-antiviral or antiretroviral therapy alone, and safety/tolerability were assessed throughout the study. Coadministration of the 3-direct-acting-antiviral regimen increased the geometric mean maximum plasma concentration (Cmax) and the area under the curve (AUC) of dolutegravir by 22% (central value ratio [90% confidence intervals], 1.219 [1.153, 1.288]) and 38% (1.380 [1.295, 1.469]), respectively. Abacavir geometric mean Cmax and AUC values decreased by 13% (0.873 [0.777, 0.979]) and 6% (0.943 [0.901, 0.986]), while those for lamivudine decreased by 22% (0.778 [0.719, 0.842]) and 12% (0.876 [0.821, 0.934]). For the 3-direct-acting-antiviral regimen, geometric mean Cmax and AUC during coadministration were within 18% of measurements made during administration of the 3-direct-acting-antiviral regimen alone, although trough concentrations for paritaprevir were 34% (0.664 [0.585, 0.754]) and 27% (0.729 [0.627, 0.847]) lower with dolutegravir and abacavir-lamivudine, respectively. All study treatments were generally

Hepatitis C Virus: Viral Quasispecies and Genotypes

PubMed Central

Tsukiyama-Kohara, Kyoko; Kohara, Michinori

2017-01-01

Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance. PMID:29271914

Animal model for hepatitis C virus infection.

PubMed

Tsukiyama-Kohara, Kyoko; Kohara, Michinori

2015-01-01

Hepatitis C virus (HCV) infects more than 170 million people in the world and chronic HCV infection develops into cirrhosis and hepatocellular carcinoma (HCC). Recently, the effective compounds have been approved for HCV treatment, the protease inhibitor and polymerase inhibitor (direct acting antivirals; DAA). DAA-based therapy enabled to cure from HCV infection. However, development of new drug and vaccine is still required because of the generation of HCV escape mutants from DAA, development of HCC after treatment of DAA, and the high cost of DAA. In order to develop new anti-HCV drug and vaccine, animal infection model of HCV is essential. In this manuscript, we would like to introduce the history and the current status of the development of HCV animal infection model.

Predominance of hepatitis C virus Q80K among NS3 baseline-resistance-associated amino acid variants in direct-antiviral-agent-naïve patients with chronic hepatitis: single-centre experience.

PubMed

Ruggiero, Tina; Proietti, Alex; Boglione, Lucio; Milia, Maria Grazia; Allice, Tiziano; Burdino, Elisa; Orofino, Giancarlo; Bonora, Stefano; Di Perri, Giovanni; Ghisetti, Valeria

2015-11-01

In the era of direct-acting antiviral agents (DAAs), hepatitis C virus (HCV) genotyping tests at baseline are controversial. The HCV NS3-Q80K polymorphism is associated with resistance to the recently approved NS3 inhibitor simeprevir (SMV) when combined with PEG-interferon and ribavirin (PEG-IFN/RBV) and alternative therapy should be considered for patients with baseline Q80K. The aim of this study was to provide an estimate of Q80K prevalence at baseline in a study group of 205 DAA-naïve patients (21% of them with HIV coinfection) using NS3 full-population direct sequencing to detect resistance-associated amino acid variants (RAVs). NS3 RAVs were identified in 56 patients (27.3%). Q80K was the most frequently reported one (41%), in both HIV/HCV-coinfected and HCV-monoinfected patients, but it was only detectable in cases of HCV-subtype 1a infection. Therefore, in clinical practice, an NS3-Q80K genotyping test prior to simeprevir plus PEG-IFN/RBV treatment is highly recommended.

The Challenge of Treating Children With Hepatitis C Virus Infection.

PubMed

Indolfi, Giuseppe; Thorne, Claire; El Sayed, Manal H; Giaquinto, Carlo; Gonzalez-Peralta, Regino P

2017-06-01

The development of oral hepatitis C virus (HCV) direct-acting antivirals (DAAs) has revolutionized the therapeutic field. Nowadays, multiple safe and highly effective antiviral regimens are commercially available to treat adults with hepatitis C infection. These new regimens for the first time genuinely raise the prospects of eradicating HCV. Many challenges, however, remain from identifying infected individuals to optimizing treatment and ensuring global access to antiviral therapy to all population groups, including children. Recently, in April 2017, the association of sofosbuvir with ribavirin and the fixed-dose combination sofosbuvir/ledipasvir have been approved by the Food and Drug Administration for treatment of children with chronic HCV infection 12 years of age and older. The only drugs currently approved for children younger than 12 years are pegylated interferon and ribavirin. There are 6 registered ongoing pediatric trials assessing safety and efficacy of DAAs, but their current completion timelines are years away. Herein, we summarize the state of the art of DAAs' development for adult and children and highlight the crucial importance of overcoming barriers to treating children with HCV.

Cost per care of the first year of direct antiviral agents in the Liguria Region: a multicenter analysis

PubMed Central

Cenderello, Giovanni; Fanizza, Caterina; Marenco, Simona; Nicolini, Laura Ambra; Artioli, Stefania; Baldissarro, Isabella; Dentone, Chiara; De Leo, Pasqualina; Di Biagio, Antonio

2017-01-01

Aims Despite the remarkable efficacy shown in clinical practice, concerns have been raised about the costs associated with direct antiviral agent (DAA) therapy. This article presents the real-life costs for DAA treatment sustained by the Italian National Health Service in the Liguria Region (Northern Italy). Methods A retrospective analysis of the cost per care sustained for DAA treatment, relating to the period from January 1 to December 31, 2015 in five centers in Liguria was performed. All patients undergoing DAA-based treatments for hepatitis C virus (HCV) infection were enrolled. On-treatment costs included: HCV treatment, laboratory test, outpatient services, attended visits, drugs used for the management of adverse events (erythropoietin, albumin or red blood cell packs) and inpatient service admissions. Results In total, 327 patients were enrolled. No difference in terms of sustained virologic response (SVR) rate among different treatments was reported. The majority (85.0%) of patients did not report any side effects and only 15 (4.6%) required hospital admission. Forty-two patients (12.8%) required high-cost drugs for the management of adverse events. The overall cost sustained was €14,744,433. DAA±ribavirin (RBV) accounted for the wide majority of this cost (98.9%; €14,585,123). Genotype (GT) 1, the most commonly treated GT, was associated with an average cost of €43,445 per patient. Detailed analysis of the costs for GT 1 showed the treatment based on ritonavir boosted paritaprevir/ombitasvir + dasabuvir±RBV with an average cost of €24,978 (RBV+) and €25,448 (RBV−) per patient was the most cost-effective. The average cost per SVR was €48,184. Once again, the ritonavir boosted paritaprevir/ombitasvir + dasabuvir regimen was associated with the lowest cost/SVR (€25,448/SVR [GT 1b] and similar results for other GTs). Conclusion Antiviral regimen is the major contributor to costs in the treatment of HCV infection. Appropriate regimen

Curing the historically incurable: treatment success with ledipasvir/sofosbuvir for chronic hepatitis C virus in a heavily treatment-experienced individual.

PubMed

Johnson, S W; Davis, M M; Stever, L M; Priest, D H

2016-12-01

Significant progression in the treatment of chronic hepatitis C virus has been made with the introduction of direct-acting antivirals (DAAs). However, limited data are available for the retreatment of individuals who have failed multiple prior DAAs. We report a single case of an individual who was unsuccessfully treated with five prior hepatitis C virus treatment regimens including simeprevir plus sofosbuvir who was successfully cured after treatment with ledipasvir/sofosbuvir. Ledipasvir/sofosbuvir may be an option for treating patients who have failed multiple prior DAA regimens; however, further research is warranted. © 2016 John Wiley & Sons Ltd.

Demonstration Advanced Avionics System (DAAS), Phase 1

NASA Technical Reports Server (NTRS)

Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

1981-01-01

Demonstration advanced anionics system (DAAS) function description, hardware description, operational evaluation, and failure mode and effects analysis (FMEA) are provided. Projected advanced avionics system (PAAS) description, reliability analysis, cost analysis, maintainability analysis, and modularity analysis are discussed.

Pre- Versus Posttransplant Treatment of Hepatitis C Virus With Direct-Acting Antivirals in Liver Transplant Recipients: More Issues to be Solved.

PubMed

Abdelqader, Abdelhai; Kabacam, Gokhan; Woreta, Tinsay A; Hamilton, James P; Luu, Harry; Al Khalloufi, Kawtar; Saberi, Behnam; Philosophe, Benjamin; Cameron, Andrew M; Gurakar, Ahmet

2017-02-01

Our goal was to investigate wait times related to hepatitis C virus treatment with direct acting antivirals before versus after liver transplant at a single center as well as wait times for insurance approval for preemptive treatment with these agents after liver transplant. We retrospectively evaluated hepatitis C virus infections in transplant recipients of deceased liver donations in 2014 and 2015. Demographics, hepatocellular carcinoma incidence, Model for End-Stage Liver Disease scores, and transplant wait times were compared between patients treated before or after liver transplant. Wait times to approval of direct-acting antiviral treatment were evaluated in those untreated before transplant. During our study period, of 67 deceased-donor liver transplants, 21 patients received hepatitis C virus treatment pretransplant (treated group) and 46 patients were not treated pretransplant (untreated group). Twenty-five patients in the untreated group received hepatitis C virus-positive donations, with all in this group treated with direct-acting antivirals. We found no statistically significant differences regarding age, sex, race, donation after cardiac death, or incidence of hepatocellular carcinoma between groups. The treated group had a longer median wait time (287 vs 172 days; P = .02). Twelve of the 46 untreated patients (26.1%) developed biopsy-proven hepatitis C virus-related relapse (median 87 days; range, 55-383 days). Preemptive direct-acting antiviral therapy was initiated at a median of 81 days in the untreated group. Although treatment of hepatitis C virus before liver transplant is an attractive option to eliminate the risk of complications, it can limit the donor pool for recipients to uninfected donors, significantly increasing wait times in regions with large hepatitis C virus-positive donor pools. Allocation of Model for End-Stage Liver Disease score was not different between the treated and untreated groups. Insurance companies should revise their

The impact of the new antiviral regimens on patient reported outcomes and health economics of patients with chronic hepatitis C.

PubMed

Younossi, Zobair; Henry, Linda

2014-12-15

Hepatitis C is an important cause of chronic liver disease worldwide with an estimated 170 million people infected. Hepatitis C virus (HCV)-infected patients are physically and mentally impacted by fatigue, depression and anxiety causing an impairment of health related quality of life (HRQOL), lower worker productivity and other patient reported outcomes (PROs). Although anti-HCV regimens containing first generation direct acting antiviral agents (DAAs) were associated with significant side effects, the second generation DAAs, sofosbuvir (SOF) and simeprevir (SMV), are associated with fewer side effects, better tolerability and high cure rates. Despite these advantages, key stakeholders are currently trying to find ways to best integrate these new therapeutic regimens into the management of patients with chronic hepatitis C for the benefit of all. The purpose of this article is to offer insight into the other key and equally important outcomes (PRO's, HRQOL and cost) which should be considered when assessing the applicability of these new regimens for the care of patients infected with HCV. Our review provides evidence that the new treatment regimens for HCV not only have high efficacy rates but are also associated with better patient reported outcomes and cost per case of HCV cured. Additionally, compared to other medical interventions, these new regimens are cost-effective from a societal perspective. Copyright © 2014. Published by Elsevier Ltd.

Treatment of chronic hepatitis C in patients with HIV/HCV coinfection

PubMed Central

Coppola, Nicola; Martini, Salvatore; Pisaturo, Mariantonietta; Sagnelli, Caterina; Filippini, Pietro; Sagnelli, Evangelista

2015-01-01

Hepatitis C virus (HCV) infection is one of the most frequent causes of comorbidity and mortality in the human immunodeficiency virus (HIV) population, and liver-related mortality is now the second highest cause of death in HIV-positive patients, so HCV infection should be countered with adequate antiviral therapy. In 2011 began the era of directly acting antivirals (DAAs) and the HCV NS3/4A protease inhibitors telaprevir and boceprevir were approved to treat HCV-genotype-1 infection, each one in combination with pegylated interferon alfa (Peg-IFN) + ribavirin (RBV). The addition of the first generation DAAs, strongly improved the efficacy of antiviral therapy in patients with HCV-genotype 1, both for the HCV-monoinfected and HIV/HCV coinfected, and the poor response to Peg-IFN + RBV in HCV/HIV coinfection was enhanced. These treatments showed higher rates of sustained virological response than Peg-IFN + RBV but reduced tolerability and adherence due to the high pill burden and the several pharmacokinetic interactions between HCV NS3/4A protease inhibitors and antiretroviral drugs. Then in 2013 a new wave of DAAs arrived, characterized by high efficacy, good tolerability, a low pill burden and shortened treatment duration. The second and third generation DAAs also comprised IFN-free regimens, which in small recent trials on HIV-positive patients have shown comforting preliminary results in terms of efficacy, tolerability and adherence. PMID:25674512

Demonstration Advanced Avionics System (DAAS) functional description. [Cessna 402B aircraft

NASA Technical Reports Server (NTRS)

1980-01-01

A comprehensive set of general aviation avionics were defined for integration into an advanced hardware mechanization for demonstration in a Cessna 402B aircraft. Block diagrams are shown and system and computer architecture as well as significant hardware elements are described. The multifunction integrated data control center and electronic horizontal situation indicator are discussed. The functions that the DAAS will perform are examined. This function definition is the basis for the DAAS hardware and software design.

Modeling HCV cure after an ultra-short duration of therapy with direct acting agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goyal, Ashish; Lurie, Yoav; Meissner, Eric G.

In cases of sustained-virological response (SVR or cure) after an ultra-short duration (≤ 27 days) of direct-acting antiviral (DAA)-based therapy, despite HCV being detected at end of treatment (EOT), have been reported. Established HCV mathematical models that predict the treatment duration required to achieve cure do not take into account the possibility that the infectivity of virus produced during treatment might be reduced. The aim of this study was to develop a new mathematical model that considers the fundamental and critical concept that HCV RNA in serum represents both infectious virus (V i) and non-infectious virus (V ni) in ordermore » to explain the observation of cure with ultrashort DAA therapy. Established HCV models were compared to the new mathematical model to retrospectively explain cure in 2 patients who achieved cure after 24 or 27 days of paritaprevir, ombitasvir, dasabuvir, ritonavir and ribavirin or sofosbuvir plus ribavirin, respectively. Fitting established models with measured longitudinal HCV viral loads indicated that in both cases, cure would not have been expected without an additional 3–6 weeks of therapy after the actual EOT. In contrast, the new model fits the observed outcome by considering that in addition to blocking V i and V ni production (ε~0.998), these DAA + ribavirin treatments further enhanced the ratio of V ni to V i, thus increasing the log (V ni/V i) from 1 at pretreatment to 6 by EOT, which led to <1 infectious-virus particle in the extracellular body fluid (i.e., cure) prior to EOT. This new model can explain cure after short duration of DAA + ribavirin therapy by suggesting that a minimum 6-fold increase of log (V ni/V i) results from drug-induced enhancement of the V ni/V i.« less

Modeling HCV cure after an ultra-short duration of therapy with direct acting agents

DOE PAGES

Goyal, Ashish; Lurie, Yoav; Meissner, Eric G.; ...

2017-06-30

In cases of sustained-virological response (SVR or cure) after an ultra-short duration (≤ 27 days) of direct-acting antiviral (DAA)-based therapy, despite HCV being detected at end of treatment (EOT), have been reported. Established HCV mathematical models that predict the treatment duration required to achieve cure do not take into account the possibility that the infectivity of virus produced during treatment might be reduced. The aim of this study was to develop a new mathematical model that considers the fundamental and critical concept that HCV RNA in serum represents both infectious virus (V i) and non-infectious virus (V ni) in ordermore » to explain the observation of cure with ultrashort DAA therapy. Established HCV models were compared to the new mathematical model to retrospectively explain cure in 2 patients who achieved cure after 24 or 27 days of paritaprevir, ombitasvir, dasabuvir, ritonavir and ribavirin or sofosbuvir plus ribavirin, respectively. Fitting established models with measured longitudinal HCV viral loads indicated that in both cases, cure would not have been expected without an additional 3–6 weeks of therapy after the actual EOT. In contrast, the new model fits the observed outcome by considering that in addition to blocking V i and V ni production (ε~0.998), these DAA + ribavirin treatments further enhanced the ratio of V ni to V i, thus increasing the log (V ni/V i) from 1 at pretreatment to 6 by EOT, which led to <1 infectious-virus particle in the extracellular body fluid (i.e., cure) prior to EOT. This new model can explain cure after short duration of DAA + ribavirin therapy by suggesting that a minimum 6-fold increase of log (V ni/V i) results from drug-induced enhancement of the V ni/V i.« less

ACES M and S: Unmitigated Factorial Encounter Study on DAA/TCAS Interoperability

NASA Technical Reports Server (NTRS)

Thipphavong, David; Cone, Andrew; Park, Chunki; Lee, Seung Man; Santiago, Confesor

2016-01-01

Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA alerting and guidance systems. This presentation contains the results of two combinatorial encounter analysis studies using NASA's SAA Control fast-time simulation capability for this purpose. In these studies, encounters between two aircraft were simulated one at a time for the full factorial combination of encounter geometries (e.g., encounter angle, CPA offset) and aircraft performance (e.g., ownership and intruder ground speeds and vertical rates). The first study analyzes the relationships (e.g., timeline) between the different alerting-safety regions in the SC-228 MOPS (in order of increasing severity): 1) DAA warning alert, 2) well clear recovery (WCR) guidance, 3) DAA-Collision Avoidance (CA), and 4) TCAS RA. This study will focus primarily on encounter situations in which TCAS RA occurs prior to any of the other alerting-safety boundaries. In particular, this study will investigate whether using vertical distance or vertical distance at closest point of approach (i.e., vertical miss distance or VMD) is more appropriate for the definition of the DAA-CA region. In addition, cases where transitions between different regions skip an intermediate region will be analyzed. The second study in this presentation explores a proposal to use an altitude rate error threshold to determine if vertical maneuvers are acceptable for DAA WCR guidance against non-cooperative intruders. This study incorporates the radar from the Honeywell sensor model and examines a series of

Long-Term Follow-Up of Resistance-Associated Substitutions in Hepatitis C Virus in Patients in Which Direct Acting Antiviral-Based Therapy Failed.

PubMed

Yoshida, Kanako; Hai, Hoang; Tamori, Akihiro; Teranishi, Yuga; Kozuka, Ritsuzo; Motoyama, Hiroyuki; Kawamura, Etsushi; Hagihara, Atsushi; Uchida-Kobayashi, Sawako; Morikawa, Hiroyasu; Enomoto, Masaru; Murakami, Yoshiki; Kawada, Norifumi

2017-05-03

We evaluated the transition of dominant resistance-associated substitutions (RASs) in hepatitis C virus during long-term follow-up after the failure of DAAs (direct acting antivirals)-based therapy. RASs in non-structure (NS)3/4A, NS5A, NS5B, and deletions in NS5A from 20 patients who failed simeprevir/pegylated-interferon/ribavirin (SMV/PEG-IFN/RBV) and 25 patients who failed daclatasvir/asunaprevir (DCV/ASV) treatment were examined by direct sequencing. With respect to SMV/PEG-IFN/RBV treatment, RAS was detected at D168 in NS3/4A but not detected in NS5A and NS5B at treatment failure in 16 of 20 patients. During the median follow-up period of 64 weeks, the RAS at D168 became less dominant in 9 of 16 patients. Among 25 DCV/ASV failures, RASs at D168, L31, and Y93 were found in 57.1%, 72.2%, and 76.9%, respectively. NS5A deletions were detected in 3 of 10 patients treated previously with SMV/PEG-IFN/RBV. The number of RASs in the breakthrough patients exceeded that in relapsers (mean 3.9 vs. 2.7, p < 0.05). RAS at D168 in NS3/4A became less dominant in 6 of 15 patients within 80 weeks. Y93H emerged at the time of relapse, then decreased gradually by 99% at 130 weeks post-treatment. Emerged RASs were associated with the clinical course of treatment and could not be detected during longer follow-up.

Discovery and preclinical development of dasabuvir for the treatment of hepatitis C infection.

PubMed

El Kassas, Mohamed; Elbaz, Tamer; Hafez, Enas; Wifi, Mohamed Naguib; Esmat, Gamal

2017-06-01

Hepatitis C virus (HCV) is a leading cause of liver-related morbidity and mortality. Positively, the introduction of new directly-acting antivirals (DAAs) have led to dramatic improvements in response rates to antiviral therapy. Furthermore, newer generations of DAAs have demonstrated better safety profiles as well as efficacy than older generations. Current treatment recommendations are based on different combinations of DAAs. Current combination therapies rely on agents that target the different steps of viral replication by using different molecules from various DAAs families. Areas covered: In this review, the authors summarize data from of one of the recently developed NS5B polymerase inhibitors, dasabuvir, formerly known as ABT-333. Herein, the authors discuss the drug discovery data for dasabuvir including data from preclinical, toxicological resistance studies. The authors also review dasabuvir's clinical efficacy across various clinical challenges, in addition to its limitations in clinical practice. Expert opinion: Dasabuvir represents an important medical advance when used as a combination therapy for HCV. Unfortunately, it does present limitations like low genotypic coverage and further research is still required to address some of the lingering issues.

Dancing with chemical formulae of antivirals: A panoramic view (Part 2).

PubMed

De Clercq, Erik

2013-11-15

In this second part of "Dancing with antivirals as chemical formulae" I will focus on a number of chemical compounds that in the last few years have elicited more than common attraction from a commercial viewpoint: (i) favipiravir (T-705), as it is active against influenza, but also several other RNA viruses; (ii) neuraminidase inhibitors such as zanamivir and oseltamivir; (iii) peramivir and laninamivir octanoate, which might be effective against influenza virus following a single (intravenous or inhalation) administration; (iv) sofosbuvir, the (anticipated) cornerstone for the interferon-free therapy of HCV infections; (v) combinations of DAAs (direct antiviral agents) to achieve, in no time, a sustained virus response (SVR) against HCV infection; (vi) HIV protease inhibitors, the latest and most promising being darunavir; (vii) the integrase inhibitors (INIs) (raltegravir, elvitegravir, dolutegravir), representing a new dimension in the anti-HIV armamentarium; (viii), a new class of helicase primase inhibitors (HPIs) that may exceed acyclovir and the other anti-herpes compounds in both potency and safety; (ix) CMX-001, as the latest of Dr. Antonín Holý's legacy for its activity against poxviruses and CMV infections, and (x) noroviruses for which the ideal antiviral compounds are still awaited for. Copyright © 2013 Elsevier Inc. All rights reserved.

Host-Targeting Agents to Prevent and Cure Hepatitis C Virus Infection.

PubMed

Zeisel, Mirjam B; Crouchet, Emilie; Baumert, Thomas F; Schuster, Catherine

2015-11-02

Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma (HCC) which are leading indications of liver transplantation (LT). To date, there is no vaccine to prevent HCV infection and LT is invariably followed by infection of the liver graft. Within the past years, direct-acting antivirals (DAAs) have had a major impact on the management of chronic hepatitis C, which has become a curable disease in the majority of DAA-treated patients. In contrast to DAAs that target viral proteins, host-targeting agents (HTAs) interfere with cellular factors involved in the viral life cycle. By acting through a complementary mechanism of action and by exhibiting a generally higher barrier to resistance, HTAs offer a prospective option to prevent and treat viral resistance. Indeed, given their complementary mechanism of action, HTAs and DAAs can act in a synergistic manner to reduce viral loads. This review summarizes the different classes of HTAs against HCV infection that are in preclinical or clinical development and highlights their potential to prevent HCV infection, e.g., following LT, and to tailor combination treatments to cure chronic HCV infection.

Interferon-free therapy of chronic hepatitis C with direct-acting antivirals does not change the short-term risk for de novo hepatocellular carcinoma in patients with liver cirrhosis.

PubMed

Mettke, F; Schlevogt, B; Deterding, K; Wranke, A; Smith, A; Port, K; Manns, M P; Vogel, A; Cornberg, M; Wedemeyer, H

2018-02-01

Hepatitis C virus (HCV) clearance with IFN-based therapies reduces the incidence of hepatocellular carcinoma (HCC). There has been some debate if IFN-free therapy with direct-acting antivirals alters the risk for HCC. To investigate the HCC incidence in cirrhotic HCV patients who cleared HCV with direct-acting antivirals vs untreated controls. We prospectively monitored 373 patients with chronic hepatitis C who received IFN-free therapies with direct-acting antiviral after January 2014. A retrospective control cohort of untreated cirrhotic patients was recruited out of 3715 HCV patients who were followed at our centre between 2007 and 2013, with similar HCC screening protocols. 158 direct-acting antiviral-treated and 184 control patients with liver cirrhosis were included in this analysis. The groups did not differ in gender and genotype distribution, severity of liver disease and prevalence of diabetes mellitus. Patients were followed up for a median of 440 (range 91-908) and 592 (range 90-1000) days. HCCs developed in 6 and 14 patients during follow-up, resulting in an incidence of 2.90 vs 4.48 HCCs per 100 person-years. In the direct-acting antiviral-treated group, there was no new case of HCC later than 450 days after treatment initiation. In multivariate analysis, higher MELD-Scores and AFP-levels were independently associated with HCC development. Transplant-free patient survival was similar in both groups. IFN-free direct-acting antiviral therapy of chronic hepatitis C does not alter the short-term risk for HCC in patients with liver cirrhosis. A reduced HCC incidence may become evident after more than 1.5 years of follow-up. © 2017 John Wiley & Sons Ltd.

Multiplex Liquid Chromatography-Tandem Mass Spectrometry Assay for Simultaneous Therapeutic Drug Monitoring of Ribavirin, Boceprevir, and Telaprevir

PubMed Central

Aouri, Manel; Moradpour, Darius; Cavassini, Matthias; Mercier, Thomas; Buclin, Thierry; Csajka, Chantal; Telenti, Amalio; Rauch, Andri

2013-01-01

New directly acting antivirals (DAAs) that inhibit hepatitis C virus (HCV) replication are increasingly used for the treatment of chronic hepatitis C. A marked pharmacokinetic variability and a high potential for drug-drug interactions between DAAs and numerous drug classes have been identified. In addition, ribavirin (RBV), commonly associated with hemolytic anemia, often requires dose adjustment, advocating for therapeutic drug monitoring (TDM) in patients under combined antiviral therapy. However, an assay for the simultaneous analysis of RBV and DAAs constitutes an analytical challenge because of the large differences in polarity among these drugs, ranging from hydrophilic (RBV) to highly lipophilic (telaprevir [TVR]). Moreover, TVR is characterized by erratic behavior on standard octadecyl-based reversed-phase column chromatography and must be separated from VRT-127394, its inactive C-21 epimer metabolite. We have developed a convenient assay employing simple plasma protein precipitation, followed by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) for the simultaneous determination of levels of RBV, boceprevir, and TVR, as well as its metabolite VRT-127394, in plasma. This new, simple, rapid, and robust HPLC-MS/MS assay offers an efficient method of real-time TDM aimed at maximizing efficacy while minimizing the toxicity of antiviral therapy. PMID:23629707

Restrictions for reimbursement of direct-acting antiviral treatment for hepatitis C virus infection in Canada: a descriptive study

PubMed Central

Marshall, Alison D.; Saeed, Sahar; Barrett, Lisa; Cooper, Curtis L.; Treloar, Carla; Bruneau, Julie; Feld, Jordan J.; Gallagher, Lesley; Klein, Marina B.; Krajden, Mel; Shoukry, Naglaa H.; Taylor, Lynn E.; Grebely, Jason

2016-01-01

Background: In Canada, interferon-free, direct-acting antiviral hepatitis C virus (HCV) regimens are costly. This presents challenges for universal drug coverage of the estimated 220 000 people with chronic HCV infection nationwide. The study objective was to appraise criteria for reimbursement of 4 HCV direct-acting antivirals in Canada. Methods: We reviewed the reimbursement criteria for simeprevir, sofosbuvir, ledipasvir-sofosbuvir and paritaprevir-ritonavir-ombitasvir plus dasabuvir in the 10 provinces and 3 territories. Data were extracted from April 2015 to June 2016. The primary outcomes extracted from health ministerial websites were: 1) minimum fibrosis stage required, 2) drug and alcohol use restrictions, 3) HIV coinfection restrictions and 4) prescriber type restrictions. Results: Overall, 85%-92% of provinces/territories limited access to patients with moderate fibrosis (Meta-Analysis of Histologic Data in Viral Hepatitis stage F2 or greater, or equivalent). There were no drug and alcohol use restrictions; however, several criteria (e.g., active injection drug use) were left to the discretion of the physician. Quebec did not reimburse simeprevir and sofosbuvir for people coinfected with HIV; no restrictions were found in the remaining jurisdictions. Prescriber type was restricted to specialists in up to 42% of provinces/territories. Interpretation: This review of criteria of reimbursement of HCV direct-acting antivirals in Canada showed substantial interjurisdictional heterogeneity. The findings could inform health policy and support the development and adoption of a national HCV strategy. PMID:28018873

Demonstration of near-elimination of hepatitis C virus among a prison population: the Lotus Glen Correctional Centre hepatitis C treatment project.

PubMed

Bartlett, Sofia R; Fox, Penny; Cabatingan, Harris; Jaros, Anissa; Gorton, Carla; Lewis, Rhondda; Priscott, Eugene; Dore, Gregory J; Russell, Darren B

2018-03-12

Micro-elimination of hepatitis C virus (HCV) infection through rapid uptake of government-funded direct-acting antiviral (DAA) therapy within an Australian prison setting is demonstrated. During a 22 month period, 119 patients initiated treatment for chronic HCV infection, with HCV in-prison viremic prevalence declining from 12% to 1%.

How much of a problem is resistance in treating hepatitis C?

PubMed

Forton, Daniel M

2016-12-01

Directly acting antiviral drug (DAA) treatments represent a major advance in hepatitis C management, achieving virological cures in excess of 90%. When treatment failure occurs, it is mostly due to relapse with the emergence of resistance-associated variants. Data from in-vitro studies and clinical trials have enabled characterization of the amino acid substitutions in antiviral drug targets that confer reduced susceptibility to DAAs. These resistance-associated substitutions (RASs) may exist prior to treatment, and are associated with, but do not inevitably result in, treatment failure. The most important RASs with current regimens occur in the NS5A protein of viral variants, which may persist for years after treatment. The optimal strategy is to prevent resistance through administering the best treatment, appropriately matched to patient and virological characteristics, for example the presence of cirrhosis, prior exposure to interferon and so on. International treatment guidelines have been developed to select treatments, which may vary in duration and coadministration with ribavirin. Routine resistance testing prior to treatment of naive patients is not generally recommended. Next-generation DAAs will further reduce the emergence of RASs and, because of activity against RASs to currently used DAAs, will be used as rescue therapies for patients who have failed treatment.

Current treatment of chronic hepatitis C in China: Dilemma and potential problems

PubMed Central

Han, Qun-Ying; Liu, Zheng-Wen

2016-01-01

Major advances have been made in the treatment of chronic hepatitis C virus (HCV) infection with the advent of direct-acting antiviral agents (DAAs). China has the most cases of HCV infection worldwide, but none of the DAAs has been approved in mainland China so far, and interferon (IFN)-α-based treatment remains the standard of care. HCV patients without response or with contraindications to IFN-based therapy have no alternative options. However, many patients buy DAAs, especially the generic forms of sofosbuvir, from other countries or areas. Under these circumstances, the use of these drugs may cause many predictable and unpredictable problems in ethics, law and medical practice. Given the obstacles of legal accessibility to DAAs and the potential problems of obtaining and using DAAs in China, the early launching of the DAAs in China or the legalization of buying drugs from areas outside China and using these drugs in China is an urgent issue and needs to be dealt with as soon as possible, in the interest of the patients. PMID:27217693

Current treatment of chronic hepatitis C in China: Dilemma and potential problems.

PubMed

Han, Qun-Ying; Liu, Zheng-Wen

2016-05-21

Major advances have been made in the treatment of chronic hepatitis C virus (HCV) infection with the advent of direct-acting antiviral agents (DAAs). China has the most cases of HCV infection worldwide, but none of the DAAs has been approved in mainland China so far, and interferon (IFN)-α-based treatment remains the standard of care. HCV patients without response or with contraindications to IFN-based therapy have no alternative options. However, many patients buy DAAs, especially the generic forms of sofosbuvir, from other countries or areas. Under these circumstances, the use of these drugs may cause many predictable and unpredictable problems in ethics, law and medical practice. Given the obstacles of legal accessibility to DAAs and the potential problems of obtaining and using DAAs in China, the early launching of the DAAs in China or the legalization of buying drugs from areas outside China and using these drugs in China is an urgent issue and needs to be dealt with as soon as possible, in the interest of the patients.

UAS Integration into the NAS: iHTL: DAA Display Evaluation Preliminary Results

NASA Technical Reports Server (NTRS)

Fern, Lisa; Rorie, Conrad; Shively, Jay

2014-01-01

The integrated human-in-the-loop (iHITL) simulation examined the effect of four different Detect-and-Avoid (DAA) display concepts on unmanned aircraft system (UAS) pilots' ability to maintain safe separation. The displays varied in the type and amount of guidance they provided to pilots. The study's background and methodology are discussed, followed by a presentation of the preliminary 'measured response' data (i.e., pilots' end-to-end response time in reacting to traffic alerts on their DAA display). Results indicate that display type had moderate to no affect on pilot measured response times.

The pedagogical value of Disassemble/Analyze/Assemble (DAA) activities: Assessing the potential for motivation and transfer

NASA Astrophysics Data System (ADS)

Dalrymple, Odesma Onika

Undergraduate engineering institutions are currently seeking to improve recruiting practices and to retain engineering majors particularly by addressing what many studies document as a major challenge of poor instruction. There is an undisputed need for instructional practices that motivate students in addition to facilitating the transfer of learning beyond the classroom. Reverse engineering and product dissection, more broadly termed Disassemble/Analyze/Assemble (DAA) activities, have shown potential to address these concerns, based on the reviews of students and professors alike. DAA activities involve the systematic deconstruction of an artifact, the subsequent analysis and possible reconstruction of its components for the purpose of understanding the embodied fundamental concepts, design principles and developmental processes. These activities have been part of regular industry practice for some time; however, the systematic analysis of their benefits for learning and instruction is a relatively recent phenomenon. A number of studies have provided highly descriptive accounts of curricula and possible outcomes of DAA activities; but, relatively few have compared participants doing DAA activities to a control group doing more traditional activities. In this respect, two quasi-experiments were conducted as part of a first-year engineering laboratory, and it was hypothesized that students who engaged in the DAA activity would be more motivated and would demonstrate higher frequencies of transfer than the control. A DAA activity that required students to disassemble a single-use camera and analyze its components to discover how it works was compared to a step-by-step laboratory activity in the first experiment and a lecture method of instruction in the second experiment. In both experiments, over forty percent of the students that engaged in the DAA activity demonstrated the ability to transfer the knowledge gained about the functions of the camera's components and

Direct-Acting Antiviral Prophylaxis in Kidney Transplantation From Hepatitis C Virus-Infected Donors to Noninfected Recipients: An Open-Label Nonrandomized Trial.

PubMed

Durand, Christine M; Bowring, Mary G; Brown, Diane M; Chattergoon, Michael A; Massaccesi, Guido; Bair, Nichole; Wesson, Russell; Reyad, Ashraf; Naqvi, Fizza F; Ostrander, Darin; Sugarman, Jeremy; Segev, Dorry L; Sulkowski, Mark; Desai, Niraj M

2018-04-17

Given the high mortality rate for patients with end-stage kidney disease receiving dialysis and the efficacy and safety of hepatitis C virus (HCV) treatments, discarded kidneys from HCV-infected donors may be a neglected public health resource. To determine the tolerability and feasibility of using direct-acting antivirals (DAAs) as prophylaxis before and after kidney transplantation from HCV-infected donors to non-HCV-infected recipients (that is, HCV D+/R- transplantation). Open-label nonrandomized trial. (ClinicalTrials.gov: NCT02781649). Single center. 10 HCV D+/R- kidney transplant candidates older than 50 years with no available living donors. Transplantation of kidneys from deceased donors aged 13 to 50 years with positive HCV RNA and HCV antibody test results. All recipients received a dose of grazoprevir (GZR), 100 mg, and elbasvir (EBR), 50 mg, immediately before transplantation. Recipients of kidneys from donors with genotype 1 infection continued receiving GZR-EBR for 12 weeks after transplantation; those receiving organs from donors with genotype 2 or 3 infection had sofosbuvir, 400 mg, added to GZR-EBR for 12 weeks of triple therapy. The primary safety outcome was the incidence of adverse events related to GZR-EBR treatment. The primary efficacy outcome was the proportion of recipients with an HCV RNA level below the lower limit of quantification 12 weeks after prophylaxis. Among 10 HCV D+/R- transplant recipients, no treatment-related adverse events occurred, and HCV RNA was not detected in any recipient 12 weeks after treatment. Nonrandomized study design and a small number of patients. Pre- and posttransplantation HCV treatment was safe and prevented chronic HCV infection in HCV D+/R- kidney transplant recipients. If confirmed in larger studies, this strategy should markedly expand organ options and reduce mortality for kidney transplant candidates without HCV infection. Merck Sharp & Dohme.

Recent update of the 2017 Korean Association for the Study of the Liver (KASL) treatment guidelines of chronic hepatitis C: comparison of guidelines from other continents, 2017 AASLD/IDSA and 2016 EASL.

PubMed

Yeon, Jong Eun

2018-05-02

The paradigm for the treatment of chronic hepatitis C (CHC) has been changed due to the development of direct acting antivirals (DAAs) of hepatitis C virus (HCV). The high sustained virologic response rate and ease of administration makes the DAAs approach ideal to contribute to the complete eradication of HCV. Currently, treatment options for individual patients vary depending on the genotype or subtype of HCV, presence or absence of liver cirrhosis, previous experience of antiviral treatment or resistance associated substitutions. Because of drug avalilability, cost-effectiveness, preference, compliance and greater possibility of desirable effects and presumed patient-important outcomes may vary between countries, treatment options for individual patients are different. The review focuses on the comparing the current treatment options for CHC in other continents with the 2017 Korea Association for the Study of the Liver guidelines.

75 FR 11189 - Expanded Access to Direct-Acting Antiviral Agents for the Treatment of Chronic Hepatitis C...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

...] Expanded Access to Direct-Acting Antiviral Agents for the Treatment of Chronic Hepatitis C Infection in... hepatitis C (CHC) infection in patients with unmet medical need. This public hearing is being held to obtain.... Background A. CHC In the United States, hepatitis C virus infection causes 20 percent of all cases of acute...

Glecaprevir + pibrentasvir for treatment of hepatitis C.

PubMed

Carrion, Andres F; Martin, Paul

2018-03-01

Glecaprevir/pibrentasvir is a fixed-dose combination regimen of a new generation NS3/4A inhibitor and an NS5A inhibitor with potent antiviral activity against all hepatitis C virus (HCV) genotypes. This regimen offers a shorter course of therapy (8 weeks) for selected patients regardless of genotype and has demonstrated high virological efficacy for retreatment of individuals who previously failed an NS5A containing regimen. Glecaprevir and pibrentasvir are minimally excreted by the kidneys; thus this regimen can safely be used in individuals with severe chronic kidney disease (CKD), including those undergoing hemodialysis. Areas covered: This review covers the mechanism of action, pharmacokinetics, clinical applications, efficacy, and safety profile of glecaprevir/pibrentasvir. It also covers key phase 2 and 3 clinical trials that led to licensure of this regimen. Expert opinion: Glecaprevir/pibrentasvir is the latest antiviral regimen licensed in the United States for treatment of HCV infection. Although several other direct-acting antiviral agents (DAAs) are currently available, glecaprevir/pibrentasvir has some unique characteristics that expand treatment options for HCV infection, including patients with comorbidities such as advanced stage CKD or prior treatment failure to antiviral regimens containing other DAAs.

Hepatitis C virus protease inhibitor-resistance mutations: our experience and review.

PubMed

Wu, Shuang; Kanda, Tatsuo; Nakamoto, Shingo; Imazeki, Fumio; Yokosuka, Osamu

2013-12-21

Direct-acting antiviral agents (DAAs) for hepatitis C virus (HCV) infection are one of the major advances in its medical treatment. The HCV protease inhibitors boceprevir and telaprevir were the first approved DAAs in the United States, Europe, and Japan. When combined with peginterferon plus ribavirin, these agents increase sustained virologic response rates to 70%-80% in treatment-naïve patients and previous-treatment relapsers with chronic HCV genotype 1 infection. Without peginterferon plus ribavirin, DAA mono-therapies increased DAA-resistance mutations. Several new DAAs for HCV are now in clinical development and are likely to be approved in the near future. However, it has been reported that the use of these drugs also led to the emergence of DAA-resistance mutations in certain cases. Furthermore, these mutations exhibit cross-resistance to multiple drugs. The prevalence of DAA-resistance mutations in HCV-infected patients who were not treated with DAAs is unknown, and it is as yet uncertain whether such variants are sensitive to DAAs. We performed a population sequence analysis to assess the frequency of such variants in the sera of HCV genotype 1-infected patients not treated with HCV protease inhibitors. Here, we reviewed the literature on resistance variants of HCV protease inhibitors in treatment naïve patients with chronic HCV genotype 1, as well as our experience.

Consideration of Viral Resistance for Optimization of Direct Antiviral Therapy of Hepatitis C Virus Genotype 1-Infected Patients.

PubMed

Dietz, Julia; Susser, Simone; Berkowski, Caterina; Perner, Dany; Zeuzem, Stefan; Sarrazin, Christoph

2015-01-01

Different highly effective interferon-free treatment options for chronic hepatitis C virus (HCV) infection are currently available. Pre-existence of resistance associated variants (RAVs) to direct antiviral agents (DAAs) reduces sustained virologic response (SVR) rates by 3-53% in hepatitis C virus (HCV) genotype 1 infected patients depending on different predictors and the DAA regimen used. Frequencies of single and combined resistance to NS3, NS5A and NS5B inhibitors and consequences for the applicability of different treatment regimens are unknown. Parallel population based sequencing of HCV NS3, NS5A and NS5B genes in 312 treatment-naïve Caucasian HCV genotype 1 infected patients showed the presence of major resistant variants in 20.5% (NS3), 11.9% (NS5A), and 22.1% (NS5B) with important differences for HCV subtypes. In NS3, Q80K was observed in 34.7% and 2.1% of subtype 1a and 1b patients, respectively while other RAVs to second generation protease inhibitors were detected rarely (1.4%). Within NS5A RAVs were observed in 7.1% of subtype 1a and 17.6% in subtype 1b infected patients. RAVs to non-nucleoside NS5B inhibitors were observed in 3.5% and 44.4% of subtype 1a and 1b patients, respectively. Considering all three DAA targets all subtype 1a and 98.6% of subtype 1b infected patients were wildtype for at least one interferon free DAA regimen currently available. In conclusion, baseline resistance testing allows the selection of at least one RAVs-free treatment option for nearly all patients enabling a potentially cost- and efficacy-optimized treatment of chronic hepatitis C.

Viral eradication reduces both liver stiffness and steatosis in patients with chronic hepatitis C virus infection who received direct-acting anti-viral therapy.

PubMed

Tada, T; Kumada, T; Toyoda, H; Sone, Y; Takeshima, K; Ogawa, S; Goto, T; Wakahata, A; Nakashima, M; Nakamuta, M; Tanaka, J

2018-04-01

Whether direct-acting anti-viral therapy can reduce liver fibrosis and steatosis in patients with chronic hepatitis C virus (HCV) infection is unclear. To evaluate changes in liver stiffness and steatosis in patients with HCV who received direct-acting anti-viral therapy and achieved sustained virological response (SVR). A total of 198 patients infected with HCV genotype 1 or 2 who achieved SVR after direct-acting anti-viral therapy were analysed. Liver stiffness as evaluated by magnetic resonance elastography, steatosis as evaluated by magnetic resonance imaging-determined proton density fat fraction (PDFF), insulin resistance, and laboratory data were assessed before treatment (baseline) and at 24 weeks after the end of treatment (SVR24). Alanine aminotransferase and homeostatic model assessment-insulin resistance levels decreased significantly from baseline to SVR24. Conversely, platelet count, which is inversely associated with liver fibrosis, increased significantly from baseline to SVR24. In patients with high triglyceride levels (≥150 mg/dL), triglyceride levels significantly decreased from baseline to SVR24 (P = 0.004). The median (interquartile range) liver stiffness values at baseline and SVR24 were 3.10 (2.70-4.18) kPa and 2.80 (2.40-3.77) kPa respectively (P < 0.001). The PDFF values at baseline and SVR 24 were 2.4 (1.7-3.4)% and 1.9 (1.3-2.8)% respectively (P < 0.001). In addition, 68% (19/28) of patients with fatty liver at baseline (PDFF ≥5.2%; n = 28) no longer had fatty liver (PDFF <5.2%) at SVR24. Viral eradication reduces both liver stiffness and steatosis in patients with chronic HCV who received direct-acting anti-viral therapy (UMIN000017020). © 2018 John Wiley & Sons Ltd.

Amino acid substitutions in the hepatitis C virus core region predict hepatocarcinogenesis following eradication of HCV RNA by all-oral direct-acting antiviral regimens.

PubMed

Ogata, Fumihiro; Akuta, Norio; Kobayashi, Masahiro; Fujiyama, Shunichiro; Kawamura, Yusuke; Sezaki, Hitomi; Hosaka, Tetsuya; Kobayashi, Mariko; Saitoh, Satoshi; Suzuki, Yoshiyuki; Suzuki, Fumitaka; Arase, Yasuji; Ikeda, Kenji; Kumada, Hiromitsu

2018-06-01

Impact of substitution of aa70 in the core region (Core aa70) in HCV genotype 1b (HCV-1b) on hepatocarcinogenesis following eradication of HCV RNA by direct-acting antiviral therapy is not clear. In a retrospective study, 533 patients with HCV-related chronic liver disease, with sustained virological response defined as negative HCV RNA at 12 weeks after cessation of direct-acting antiviral therapy, were examined to evaluate the relationship between Core aa70 substitution and hepatocarcinogenesis. Twelve patients developed hepatocellular carcinoma during the follow-up period. The cumulative hepatocarcinogenesis rates were 1.7% and 2.4% at the end of 1 and 2 years, respectively. Overall, multivariate analysis identified HCV subgroup (HCV-1b with Gln70(His70); P = 0.003) and age (>65 years; P = 0.049), as pretreatment predictors of hepatocarcinogenesis. In HCV-1b patients, multivariate analysis identified post-treatment Wisteria floribunda agglutinin positive Mac-2 binding protein (>1.8 COI; P = 0.042) and HCV subgroup (HCV-1b with Gln70(His70); P = 0.071), as predictors of hepatocarcinogenesis, including post-treatment parameter. In conclusion, Core aa70 substitution in HCV-1b at the start of direct-acting antiviral therapy is an important predictor of hepatocarcinogenesis following eradication of HCV RNA. This study emphasizes the importance of detection of Core aa70 substitution before initiating antiviral therapy. © 2018 Wiley Periodicals, Inc.

Network meta-analysis of first- and second-generation protease inhibitors for chronic hepatitis C genotype 1: efficacy based on RVR and SVR 24.

PubMed

Borba, Helena H; Wiens, Astrid; Steimbach, Laiza M; Perlin, Cassio M; Tonin, Fernanda S; Pedroso, Maria L A; Fernandez-Llimos, Fernando; Pontarolo, Roberto

2017-01-01

This study aimed to compare the efficacy among direct-acting antiviral agents (first and second-generation direct-acting antiviral agents (DAAs)) with placebo and with standard dual therapy (pegylated interferon + ribavirin (Peg-IFN + RBV)) in terms of rapid virologic response (RVR) and sustained virologic response (SVR) in chronic hepatitis C genotype 1 treatment. We performed a systematic review of randomized controlled trials (RCTs) in MEDLINE, International Pharmaceutical Abstracts, Cochrane Library, SCIELO, and Scopus and conducted a network meta-analysis to compare the efficacy of boceprevir (BOC), daclatasvir (DCV), grazoprevir, simeprevir (SMV) and telaprevir (TVR), in treatment-naive and treatment-experienced patients. Sixteen studies encompassing 7171 patients were analysed. Associations between DAAs therapies (IFN-free regimens) could not be addressed since no common comparator was found in the RCTs among these associations and the other agents included in the present analysis. All agents were more efficacious than placebo or Peg-IFN + RBV in terms of RVR, while only BOC and SMV showed statistically significant superiority for the SVR outcome when compared to placebo or standard dual therapy. No significant differences between the DAAs were observed. The analysis prioritized treatment with DCV for both efficacy outcomes. Node-splitting analysis showed that our networks are robust (p > 0.05). The superiority of DAAs over placebo or standard dual therapy with Peg-IFN + RBV was confirmed, indicating the greater efficacy of DCV. This study is the first network meta-analysis that included RVR as an outcome in the evaluation of these agents via indirect comparison. Further investigation should be carried out addressing safety and tolerability outcomes.

Optimization of direct anti-viral agent treatment schedule: Focus on HCV genotype 3.

PubMed

Morisco, Filomena; Granata, Rocco; Camera, Silvia; Ippolito, Antonio; Milella, Michele; Conti, Fabio; Masetti, Chiara; Smedile, Antonella; Tundo, Paolo; Santantonio, Teresa; Valvano, Maria Rosa; Termite, Antonio; Gatti, Pietro; Messina, Vincenzo; Iacobellis, Angelo; Librandi, Marta; Caporaso, Nicola; Andriulli, Angelo

2018-03-01

Direct antiviral agents (DAAs) have led to high sustained virological responses (SVR) in hepatitis C virus (HCV) patients. However, genotype 3 patients respond to treatment in a suboptimal way. This study aims to identify which of the several treatment schedules recommended for genotype 3 would constitute the best option. Twenty-four Italian centers were involved in this real-life study of HCV genotype 3 patients treated with DAAs. To expand the number of cases, we conducted a systematic review of the literature on the outcome of genotype 3 patients treated with DAAs. A total of 233 patients with HCV genotype 3 were enrolled. Cirrhotic patients accounted for 83.7%. Overall, the SVR12 rate was achieved by 205 patients (88.0%); the SVR rates were 78.8% after sofosbuvir/ribavirin, 92.5% after sofosbuvir/daclatasvir ± ribavirin, and 100% after sofosbuvir/ledipasvir (seven patients). No difference in rate of SVR was observed in cirrhotic and non-cirrhotic patients (92.2 vs 94.4) using a combination regimen of NS5A and NS5B inhibitors.The systematic review of the literature provided data of 3311 patients: The mean weighted SVR12 rate was 84.4% (CI: 80.4-87.8); the rates varied from 79.0% (CI: 70.9-85.3) with sofosbuvir/ribavirin, to 83.7% (CI: 66.2-93.1) with sofosbuvir/ledispavir, and to 88.2% (CI: 83.3-91.7) with sofosbuvir/daclatasvir. Our results reinforce the concept that patients with HCV genotype 3 should no longer be considered difficult-to-treat individuals. The optimal therapeutic regimen for these patients appears to be the combination sofosbuvir/daclatasvir, administered for 12 weeks without the use of RBV in non-cirrhotic patients. In cirrhotics the meta-analytic approach suggests extending therapy to 24 weeks.

Direct-acting antivirals and host-targeting strategies to combat enterovirus infections.

PubMed

Bauer, Lisa; Lyoo, Heyrhyoung; van der Schaar, Hilde M; Strating, Jeroen Rpm; van Kuppeveld, Frank Jm

2017-06-01

Enteroviruses (e.g., poliovirus, enterovirus-A71, coxsackievirus, enterovirus-D68, rhinovirus) include many human pathogens causative of various mild and more severe diseases, especially in young children. Unfortunately, antiviral drugs to treat enterovirus infections have not been approved yet. Over the past decades, several direct-acting inhibitors have been developed, including capsid binders, which block virus entry, and inhibitors of viral enzymes required for genome replication. Capsid binders and protease inhibitors have been clinically evaluated, but failed due to limited efficacy or toxicity issues. As an alternative approach, host-targeting inhibitors with potential broad-spectrum activity have been identified. Furthermore, drug repurposing screens have recently uncovered promising new inhibitors with disparate viral and host targets. Together, these findings raise hope for the development of (broad-range) anti-enteroviral drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

Antiviral agents: structural basis of action and rational design.

PubMed

Menéndez-Arias, Luis; Gago, Federico

2013-01-01

During the last 30 years, significant progress has been made in the development of novel antiviral drugs, mainly crystallizing in the establishment of potent antiretroviral therapies and the approval of drugs inhibiting hepatitis C virus replication. Although major targets of antiviral intervention involve intracellular processes required for the synthesis of viral proteins and nucleic acids, a number of inhibitors blocking virus assembly, budding, maturation, entry or uncoating act on virions or viral capsids. In this review, we focus on the drug discovery process while presenting the currently used methodologies to identify novel antiviral drugs by using a computer-based approach. We provide examples illustrating structure-based antiviral drug development, specifically neuraminidase inhibitors against influenza virus (e.g. oseltamivir and zanamivir) and human immunodeficiency virus type 1 protease inhibitors (i.e. the development of darunavir from early peptidomimetic compounds such as saquinavir). A number of drugs in preclinical development acting against picornaviruses, hepatitis B virus and human immunodeficiency virus and their mechanism of action are presented to show how viral capsids can be exploited as targets of antiviral therapy.

Efficacy and safety of direct antiviral agents in a cohort of cirrhotic HCV/HIV-coinfected patients.

PubMed

Navarro, Jordi; Laguno, Montserrat; Vilchez, Helem Haydee; Guardiola, Jose M; Carrion, Jose A; Force, Luis; Cairó, Mireia; Cifuentes, Carmen; Vilaró, Josep; Cucurull, Josep; Marco, Andrés; Roget, Mercè; Erice, Eva; Crespo, Manuel

2017-10-01

New direct-acting antiviral agents (DAAs) have shown great efficacy and tolerability in clinical trials and real-life cohorts. However, data are scarce regarding efficacy and safety in cirrhotic HCV/HIV-coinfected patients. A multicentre prospective analysis was performed in 13 Spanish hospitals, including all cirrhotic HCV/HIV-coinfected patients starting DAA combinations from January to December 2015. Sustained virological response 12 weeks after treatment (SVR12) was analysed. Withdrawal due to toxicity and/or hepatic decompensation and change in liver stiffness measurement (LSM) after HCV treatment were evaluated. Patients (n = 170) were mostly male (n = 125; 74.3%) with the following HCV genotype (Gt) distribution: Gt-1a, 68 (40%); Gt-1b, 21 (12.4%); Gt-4, 47 (27.6%); and Gt-3, 26 (15.3%). Baseline median LSM was 20.6 kPa (IQR 16.1-33.7) and log10 HCV-RNA 6.1 IU/mL (IQR 5.7-6.5). Most patients had a Child-Pugh class A score (n = 127; 74.7%) and 28 (16.5%) had prior hepatic decompensation. There were 89 (52.4%) pretreated patients with 40.4% (n = 36) of null responders. Preferred regimens were as follows: sofosbuvir/ledipasvir + ribavirin, 43 (25.3%) patients; sofosbuvir + simeprevir + ribavirin, 34 (20%); sofosbuvir/ledipasvir, 26 (15.3%) and sofosbuvir + daclatasvir + ribavirin, 25 (14.7%). Overall SVR12 was 92.9% (158/170), without differences between genotypes. Pretreated patients had lower SVR12 rates compared with naive (88.8% versus 97.5%; P = 0.026). Treatment failures were as follows: 7 (4.1%) relapses; 2 (1.2%) lost to follow-up; 1 (0.6%) toxicity-related discontinuation; 1 (0.6%) hepatic decompensation; and 1 (0.6%) viral breakthrough. On-treatment hepatic decompensation was recorded in four (2.4%) patients (encephalopathy and ascites, two each). Paired LSM in 33 patients showed a decrease of 5.6 kPa (95% CI 1.8-9.2; P = 0.004). In our cohort of cirrhotic HCV/HIV-coinfected patients, DAAs were

Modelling hepatitis C therapy—predicting effects of treatment

PubMed Central

Perelson, Alan S.; Guedj, Jeremie

2015-01-01

Mathematically modelling HCV RNA changes measured in patients who receive antiviral therapy has yielded many insights into the pathogenesis and effects of treatment on the virus. By determining how rapidly HCV is cleared when viral replication is interrupted by a therapy, one can deduce how rapidly the virus is produced in patients before treatment. This knowledge, coupled with estimates of the HCV mutation rate, enables one to estimate the frequency with which drug resistant variants arise. Modelling HCV also permits the deduction of antiviral agent effectiveness at blocking HCV replication from the magnitude of the initial viral decline. One can also estimate the lifespan of an HCV infected cell from the slope of the subsequent viral decline and, determine the duration of therapy needed to cure infection. Our understanding of HCV RNA decline under IFN-based therapies needs to be revised in order to understand the HCV RNA decline kinetics seen when using direct-acting antiviral agents (DAAs). In this Review, we also discuss the unresolved issues involving understanding therapies with combinations of DAAs, such as whether a sustained virological response necessarily involves elimination of all infected cells PMID:26122475

The science of direct-acting antiviral and host-targeted agent therapy.

PubMed

Pawlotsky, Jean-Michel

2012-01-01

Direct-acting antiviral drugs targeting two major steps of the HCV life cycle, polyprotein processing and replication, and cyclophilin inhibitors, that target a host cell protein required to interact with the replication complex, have reached clinical development. In order to achieve a sustained virological response, that is, a cure of the HCV infection, it is necessary to shut down virus production, to maintain viral inhibition throughout treatment and to induce a significant, slower second-phase decline in HCV RNA levels that leads to definitive clearance of infected cells. Recent findings suggest that the interferon era is coming to an end in hepatitis C therapy and HCV infection can be cured by all-oral interferon-free treatment regimens within 12 to 24 weeks. Further results are awaited that will allow the establishment of an ideal first-line all-oral, interferon-free treatment regimen for patients with chronic HCV infection.

Hepatitis C Virus and Antiviral Drug Resistance.

PubMed

Kim, Seungtaek; Han, Kwang-Hyub; Ahn, Sang Hoon

2016-11-15

Since its discovery in 1989, hepatitis C virus (HCV) has been intensively investigated to understand its biology and develop effective antiviral therapies. The efforts of the previous 25 years have resulted in a better understanding of the virus, and this was facilitated by the development of in vitro cell culture systems for HCV replication. Antiviral treatments and sustained virological responses have also improved from the early interferon monotherapy to the current all-oral regimens using direct-acting antivirals. However, antiviral resistance has become a critical issue in the treatment of chronic hepatitis C, similar to other chronic viral infections, and retreatment options following treatment failure have become important questions. Despite the clinical challenges in the management of chronic hepatitis C, substantial progress has been made in understanding HCV, which may facilitate the investigation of other closely related flaviviruses and lead to the development of antiviral agents against these human pathogens.

An Evaluation of Detect and Avoid (DAA) Displays for Unmanned Aircraft Systems: The Effect of Information Level and Display Location on Pilot Performance

NASA Technical Reports Server (NTRS)

Fern, Lisa; Rorie, R. Conrad; Pack, Jessica S.; Shively, R. Jay; Draper, Mark H.

2015-01-01

A consortium of government, industry and academia is currently working to establish minimum operational performance standards for Detect and Avoid (DAA) and Control and Communications (C2) systems in order to enable broader integration of Unmanned Aircraft Systems (UAS) into the National Airspace System (NAS). One subset of these performance standards will need to address the DAA display requirements that support an acceptable level of pilot performance. From a pilot's perspective, the DAA task is the maintenance of self separation and collision avoidance from other aircraft, utilizing the available information and controls within the Ground Control Station (GCS), including the DAA display. The pilot-in-the-loop DAA task requires the pilot to carry out three major functions: 1) detect a potential threat, 2) determine an appropriate resolution maneuver, and 3) execute that resolution maneuver via the GCS control and navigation interface(s). The purpose of the present study was to examine two main questions with respect to DAA display considerations that could impact pilots' ability to maintain well clear from other aircraft. First, what is the effect of a minimum (or basic) information display compared to an advanced information display on pilot performance? Second, what is the effect of display location on UAS pilot performance? Two levels of information level (basic, advanced) were compared across two levels of display location (standalone, integrated), for a total of four displays. The authors propose an eight-stage pilot-DAA interaction timeline from which several pilot response time metrics can be extracted. These metrics were compared across the four display conditions. The results indicate that the advanced displays had faster overall response times compared to the basic displays, however, there were no significant differences between the standalone and integrated displays. Implications of the findings on understanding pilot performance on the DAA task, the

Treating Hepatitis C in a Ryan White-Funded HIV Clinic: Has the Treatment Uptake Improved in the Interferon-Free Directly Active Antiviral Era?

PubMed

Cope, Rebecca; Glowa, Thomas; Faulds, Samantha; McMahon, Deborah; Prasad, Ramakrishna

2016-02-01

Now that highly efficacious, interferon-free (IFN-free), direct acting antivirals (DAA) for the treatment of hepatitis C (HCV) have closed the gap between treatment and cure, identifying barriers that prevent initiation of treatment is more crucial than ever. This is a retrospective study utilizing Electronic Medical Records and Prior Authorization Records to identify HCV treatment gaps, including predictors for intention-to-treat and treatment initiation in the first 15 months of a Ryan White funded human immunodeficiency virus (HIV)/HCV co-infection clinic. This study included 128 adults ≥ 18 years old with HIV and chronic HCV infection who had visited the treatment center at least once since January 2013. Provider intent-to-treat was used to differentiate patients actively considered for treatment based on documentation kept by a multidisciplinary HCV team. Members of this group who had gone on to initiate treatment were identified. Baseline characteristics were compared. Rates of active treatment consideration and treatment initiation were 30% and 14%, respectively. HCV treatment-naïve individuals were less likely to be considered for treatment [risk ratio (RR) 1.58, 95% confidence interval (CI) 1.07-2.32] and initiate therapy (RR 2.33, 95% CI 0.97-5.60). Advanced liver disease had no significant association. Black race (RR 1.96, 95% CI 0.90-4.25) and Medicaid insurance holders (RR 1.90, 95% CI 0.95-3.82) tended to be less likely to initiate therapy. The availability of IFN-free DAA regimens has yet to increase HCV treatment uptake in our HIV/HCV co-infected population. Barriers to HCV treatment initiation have shifted from medical contraindications to socioeconomic variables.

Moderate Sustained Virologic Response Rates With 6-Week Combination Directly Acting Anti-Hepatitis C Virus Therapy in Patients With Advanced Liver Disease.

PubMed

Kattakuzhy, Sarah; Wilson, Eleanor; Sidharthan, Sreetha; Sims, Zayani; McLaughlin, Mary; Price, Angie; Silk, Rachel; Gross, Chloe; Akoth, Elizabeth; McManus, Maryellen; Emmanuel, Benjamin; Shrivastava, Shikha; Tang, Lydia; Nelson, Amy; Teferi, Gebeyehu; Chavez, Jose; Lam, Brian; Mo, Hongmei; Osinusi, Anuoluwapo; Polis, Michael A; Masur, Henry; Kohli, Anita; Kottilil, Shyamasundaran

2016-02-15

Treatment of genotype 1 hepatitis C virus (HCV) infection with combination directly acting antivirals (DAA) for 8-24 weeks is associated with high rates of sustained virologic response (SVR). We previously demonstrated that adding a third DAA to ledipasvir and sofosbuvir (LDV/SOF) can result in high SVR rates in patients without cirrhosis. In this study, we investigated whether a similar regimen would yield equivalent rates of cure in patients with advanced liver fibrosis. Fifty patients were enrolled at the Clinical Research Center of the National Institutes of Health and associated healthcare centers. Enrollment and follow-up data from April 2014 to June 2015 are reported here. Eligible participants were aged ≥18 years, had chronic HCV genotype 1 infection (serum HCV RNA ≥2000 IU/mL), and stage 3-4 liver fibrosis. HCV RNA was measured using a reverse-transcription polymerase chain reaction assay. Of patients treated with LDV, SOF, and the NS3/4A protease inhibitor GS-9451 for 6 weeks, 76% (38 of 50; 95% confidence interval, 60%-85%) had SVR achieved 12 weeks after the end of treatment. There was no statistically significant difference in treatment efficacy between treatment-naive patients (72%, 18 of 25) and those with treatment experience (80%; 20 of 25) (P = .51). Overall, 11 patients (22%) experienced virologic relapse, and 1 (2%) was lost to follow-up at 4 weeks after treatment. No serious adverse events, discontinuations, or deaths were associated with this regimen. Adding a third DAA to LDV/SOF may result in a moderate SVR rate, lower than that observed in patients without cirrhosis. Significant liver fibrosis remains an impediment to achieving SVR with short-duration DAA therapy. CT01805882. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

The New Era of Interferon-Free Treatment of Chronic Hepatitis C

PubMed Central

Solbach, Philipp; Wedemeyer, Heiner

2015-01-01

Summary Background Within the development and approval of several new direct-acting antivirals (DAA) against hepatitis C virus (HCV), a new era of hepatitis C therapy has begun. Even more treatment options are likely to become available during the next 1-2 years. Methods A summary of the current phase II and III trials investigating DAA and a review of the recent HCV guidelines was conducted. Results With the development of new potent DAA and the approval of different DAA combinations, cure rates of HCV infection of >90% are achievable for almost all HCV genotypes and stages of liver disease. Currently available DAA target different steps in the HCV replication cycle, in particular the NS3/4A protease, the NS5B polymerase, and the NS5A replication complex. Treatment duration varies between 8 and 24 weeks depending on the stage of fibrosis, prior treatment, HCV viral load, and HCV genotype. Ribavirin is required only for some treatment regimens and may be particularly beneficial in patients with cirrhosis. DAA resistance influences treatment outcome only marginally; thus, drug resistance testing is not routinely recommended before treatment. In the case of treatment failure, however, resistance testing should be performed before re-treatment with other DAA is initiated. Conclusion With the new, almost side effect-free DAA treatment options chronic HCV infection became a curable disease. The clinical benefit of DAA combination therapies in patients with advanced cirrhosis and the effects on incidence rates of hepatocellular carcinoma remain to be determined. PMID:26557839

The efficacy of direct anti-HCV drugs improves early post-liver transplant survival and induces significant changes in waiting list composition.

PubMed

Crespo, Gonzalo; Trota, Núria; Londoño, Maria-Carlota; Mauro, Ezequiel; Baliellas, Carme; Castells, Lluís; Castellote, Jose; Tort, Jaume; Forns, Xavier; Navasa, Miquel

2018-07-01

The efficacy of direct-acting antivirals (DAAs) has dramatically changed the prognosis of patients with chronic hepatitis C. We aimed to evaluate the impact of DAA therapy on the composition of the liver transplant (LT) waiting list and the early post-transplant survival. We evaluated all patients admitted to the waiting list for a primary LT between 1st January 2008 and 31st of December 2016 in Catalonia, Spain. Time span was divided into two periods according to the availability of different antiviral therapies: 2008-2013 (interferon-based therapies) and 2014-2016 (DAA). Changes in the indications of LT and the aetiology of liver disease, as well as post-LT patient survival, were evaluated according to the year of inclusion and transplantation, respectively. We included 1,483 patients. Admissions in the waiting list for hepatitis C virus (HCV)-related liver disease decreased significantly, from 47% in 2008-2013 to 35% in 2014-2016 (p <0.001), particularly because of a reduction in patients with decompensated cirrhosis. In contrast, NASH-related inclusions increased from 4% to 7% (p = 0.003). Three-year post-LT patient survival increased significantly in the second period in the whole cohort (82% vs. 91%, p = 0.002), because of better survival in anti-HCV positive patients (76% vs. 91%, p = 0.001), but not in anti-HCV negative patients (88% vs. 91% p = 0.359). Anti-HCV positive serology, the time period of 2008-2013 and higher donor age were independently associated with post-LT mortality in the whole cohort; while time period and donor age were independently associated with post-LT mortality in anti-HCV positive recipients. The high efficacy of DAAs is associated with significant changes in the composition of the LT waiting list and, more importantly, results in improved post-transplant survival. The efficacy of the new direct-acting antivirals is associated with a significant improvement in survival of patients undergoing liver transplantation

Impact of anti-HCV direct antiviral agents on graft function and immunosuppressive drug levels in kidney transplant recipients: a call to attention in the mid-term follow-up in a single-center cohort study.

PubMed

Fernández-Ruiz, Mario; Polanco, Natalia; García-Santiago, Ana; Muñoz, Raquel; Hernández, Ana M; González, Esther; Mercado, Verónica R; Fernández, Inmaculada; Aguado, José María; Praga, Manuel; Andrés, Amado

2018-01-22

The medium-term impact on graft function and immunosuppressive drug pharmacokinetics of direct antiviral agents (DAAs) among hepatitis C virus (HCV)-infected kidney transplant (KT) recipients remain unclear. We compared pre- and post-treatment 12-month trajectories of estimated glomerular filtration rate (ΔeGFR) and 24-h proteinuria (Δ24-h proteinuria) in 49 recipients treated with DAAs (mostly sofosbuvir plus ledipasvir). Among evaluable patients, 66.7% and 100.0% had undetectable viral load by week 4 and end of therapy (EoT). The sustained virologic response rate at 12 weeks was 95.8%. Overall, 80.6% of patients receiving tacrolimus required dose escalation while on DAA-based therapy (median increase of 66.7%) to maintain target levels. Tacrolimus levels resulted to be higher at 12 months compared to EoT (7.8 ± 2.1 vs. 6.7 ± 2.0 ng/ml; P-value = 0.002). No changes in graft function during the course of therapy were observed. However, eGFR significantly decreased (P-value <0.001) throughout the first 12 months after EoT. Median ΔeGFR and Δ24-h over pre- and post-treatment periods were 3.9% and -6.1% (P-value = 0.002) and -5.3% and 26.2% (P-value = 0.057). Caution should be exercised when adjusting immunosuppression in HCV-infected KT recipients upon initiation of DAAs, followed by mid-term monitoring of immunosuppressive drug levels and graft function. © 2018 Steunstichting ESOT.

Effectiveness and security of chronic hepatitis C treatment in coinfected patients in real-world.

PubMed

Uriarte-Pinto, Moisés; Navarro-Aznarez, Herminia; De La Llama-Celis, Natalia; Arazo-Garcés, Piedad; Martínez-Sapiña, Ana María; Abad-Sazatornil, María Reyes

2018-06-01

Background HIV-HCV coinfection produces high morbi-mortality. Direct-acting antivirals (DAAs) have shown high efficacy, although special attention should be paid to the risk of drug interactions. However, due to the lack of representativeness of coinfected patients in clinical trials, it is important to know real-world results. Objective To evaluate DAA treatment effectiveness in coinfected patients. We also analyse safety profile of DAA treatment and drug interactions between HCV and HIV therapy. Setting Descriptive study carried in a tertiary hospital of Spain Method HIV-HCV coinfected patients treated with DAAs between November 2014 and June 2016 were included. Main outcome measure Efficacy was measured in terms of sustained virologic response at week 12 after the end of therapy. Adverse events that led to treatment discontinuation were registered to evaluate the safety profile, and also drug interactions between DAAs and antiretroviral treatment were evaluated. Results Main HCV genotypes were 1a (34.9%) and 4 (24.5%). 51.9% were HCV previously treated, 54.7% had grade 4 liver fibrosis. SVR12 was reported in 90.6%. HCV treatment was well tolerated and there were no discontinuations because of adverse events. 30.2% of HIV treatments had to be modified before DAA treatment was started due to interactions, HIV suppression was not compromised. Conclusion DAA treatment in coinfected patients seems to be highly effective and secure. Evaluation of drug interactions must be a priority in order to maximize effectiveness and avoid toxicity.

Hepatitis C in Special Patient Cohorts: New Opportunities in Decompensated Liver Cirrhosis, End-Stage Renal Disease and Transplant Medicine.

PubMed

Hüsing, Anna; Kabar, Iyad; Schmidt, Hartmut H; Heinzow, Hauke S

2015-08-05

Worldwide, hepatitis C virus (HCV) is a common infection. Due to new antiviral approaches and the approval of direct-acting antiviral agents (DAA), HCV therapy has become more comfortable. Nevertheless, there are special patient groups, in whom treatment of HCV is still challenging. Due to only few data available, tolerability and efficacy of DAAs in special patient cohorts still remain unclear. Such special patient cohorts comprise HCV in patients with decompensated liver disease (Child-Pugh Class B or C), patients with chronic kidney disease, and patients on waiting lists to renal/liver transplantation or those with HCV recurrence after liver transplantation. HCV infection in these patient cohorts has been shown to be associated with increased morbidity and mortality and may lead to reduced graft survival after transplantation. Successful eradication of HCV results in a better outcome concerning liver-related complications and in a better clinical outcome of these patients. In this review, we analyze available data and results from recently published literature and provide an overview of current recommendations of HCV-therapy regimen in these special patient cohorts.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perelson, Alan S.; Guedj, Jeremie

Mathematically modelling changes in HCV RNA levels measured in patients who receive antiviral therapy has yielded many insights into the pathogenesis and effects of treatment on the virus. By determining how rapidly HCV is cleared when viral replication is interrupted by a therapy, one can deduce how rapidly the virus is produced in patients before treatment. This knowledge, coupled with estimates of the HCV mutation rate, enables one to estimate the frequency with which drug resistant variants arise. Modelling HCV also permits the deduction of the effectiveness of an antiviral agent at blocking HCV replication from the magnitude of themore » initial viral decline. One can also estimate the lifespan of an HCV-infected cell from the slope of the subsequent viral decline and determine the duration of therapy needed to cure infection. The original understanding of HCV RNA decline under interferon-based therapies obtained by modelling needed to be revised in order to interpret the HCV RNA decline kinetics seen when using direct-acting antiviral agents (DAAs). In addition, there also exist unresolved issues involving understanding therapies with combinations of DAAs, such as the presence of detectable HCV RNA at the end of therapy in patients who nonetheless have a sustained virologic response.« less

Modelling hepatitis C therapy—predicting effects of treatment

DOE PAGES

Perelson, Alan S.; Guedj, Jeremie

2015-06-30

Mathematically modelling changes in HCV RNA levels measured in patients who receive antiviral therapy has yielded many insights into the pathogenesis and effects of treatment on the virus. By determining how rapidly HCV is cleared when viral replication is interrupted by a therapy, one can deduce how rapidly the virus is produced in patients before treatment. This knowledge, coupled with estimates of the HCV mutation rate, enables one to estimate the frequency with which drug resistant variants arise. Modelling HCV also permits the deduction of the effectiveness of an antiviral agent at blocking HCV replication from the magnitude of themore » initial viral decline. One can also estimate the lifespan of an HCV-infected cell from the slope of the subsequent viral decline and determine the duration of therapy needed to cure infection. The original understanding of HCV RNA decline under interferon-based therapies obtained by modelling needed to be revised in order to interpret the HCV RNA decline kinetics seen when using direct-acting antiviral agents (DAAs). In addition, there also exist unresolved issues involving understanding therapies with combinations of DAAs, such as the presence of detectable HCV RNA at the end of therapy in patients who nonetheless have a sustained virologic response.« less

Hepatitis C infection in patients with hereditary bleeding disorders: epidemiology, natural history, and management.

PubMed

Papadopoulos, Nikolaos; Argiana, Vasiliki; Deutsch, Melanie

2018-01-01

Hereditary bleeding disorders include a group of diseases with abnormalities of coagulation. Prior to 1990, infection with hepatitis C virus (HCV) was mainly transmitted via pooled plasma products as a treatment for hereditary bleeding disorders. Anti-HCV positivity in these patients may be as high as >70% in some areas, while some of them have also been coinfected with human immunodeficiency virus. Since about 20% of HCV-infected patients clear the infection naturally, chronic HCV infection represents a significant health problem in this group of patients. Mortality due to chronic HCV infection is estimated to be >10 times higher in patients with hemophilia than in the general population, and is mainly due to liver cirrhosis and hepatocellular carcinoma. The antiviral treatment of HCV in patients with hereditary bleeding disorders is not different from that of any other infected patients. Nevertheless, many patients with hereditary bleeding disorders have declined (Peg)interferon-based treatment because of side effects. In recent years, multiple orally administrated direct-acting antivirals (DAAs) have been approved for HCV treatment. Unfortunately, there is not much experience from treating these patients with DAA regimens, as major studies and real-life data did not include adequate numbers of patients with inherited hemorrhagic disorders. However, the available data indicate that DAAs have an excellent safety profile with a sustained virological response rate of >90%.

Hepatitis C infection in patients with hereditary bleeding disorders: epidemiology, natural history, and management

PubMed Central

Papadopoulos, Nikolaos; Argiana, Vasiliki; Deutsch, Melanie

2018-01-01

Hereditary bleeding disorders include a group of diseases with abnormalities of coagulation. Prior to 1990, infection with hepatitis C virus (HCV) was mainly transmitted via pooled plasma products as a treatment for hereditary bleeding disorders. Anti-HCV positivity in these patients may be as high as >70% in some areas, while some of them have also been coinfected with human immunodeficiency virus. Since about 20% of HCV-infected patients clear the infection naturally, chronic HCV infection represents a significant health problem in this group of patients. Mortality due to chronic HCV infection is estimated to be >10 times higher in patients with hemophilia than in the general population, and is mainly due to liver cirrhosis and hepatocellular carcinoma. The antiviral treatment of HCV in patients with hereditary bleeding disorders is not different from that of any other infected patients. Nevertheless, many patients with hereditary bleeding disorders have declined (Peg)interferon-based treatment because of side effects. In recent years, multiple orally administrated direct-acting antivirals (DAAs) have been approved for HCV treatment. Unfortunately, there is not much experience from treating these patients with DAA regimens, as major studies and real-life data did not include adequate numbers of patients with inherited hemorrhagic disorders. However, the available data indicate that DAAs have an excellent safety profile with a sustained virological response rate of >90%. PMID:29333065

Comparative treatment effectiveness of direct acting antiviral regimens for hepatitis C: Data from the Veterans administration.

PubMed

Fox, D Steven; McGinnis, Justin J; Tonnu-Mihara, Ivy Q; McCombs, Jeffrey S

2017-06-01

Data addressing real world effectiveness of direct acting antiviral agents in hepatitis C infected patients are now emerging. This study compared the sustained virologic response rates achieved 12 weeks post-treatment in patients treated with three such agents by the Veterans Health Administration. A retrospective cohort study was conducted using patients who terminated treatment by July 1, 2015. Data were retrieved from the Veterans Health Administration electronic medical records system. Patients were included if sufficient viral load laboratory data were available to determine sustained virologic response. Applying an intention to treat approach and logistic regression analysis, the sustained virologic response rates achieved were compared across drug regimens. A total of 11 464 patients met study selection criteria. Without controlling for other risk factors, sustained virologic response at least 12 weeks post treatment was achieved in 92% of ledipasvir/ sofosbuvir, 86% of ombitasvir/paritaprevir/ritonavir/dasabuvir, and 83% of simeprevir/sofosbuvir patients. After adjusting for patient characteristics, simeprevir/sofosbuvir (93.3%) and ledipasvir/sofosbuvir (96.2%) patients were statistically more likely than ombitasvir/paritaprevir/ritonavir/dasabuvir (91.8%) patients to demonstrate sustained virologic response. Human immunodeficiency virus, hepatitis B infection, diabetes, obesity, previous treatment history and augmentation therapy using ribavirin did not impact sustained virologic response rates. Sustained virologic response rates were lower for patients under age 65, with cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, indications of fibrosis, or a non-genotype 1 infection. Women and Caucasian patients were more likely to achieve a sustained virologic response. All three direct acting antiviral regimens appear highly effective in achieving sustained virologic response. © 2016 Journal of Gastroenterology and Hepatology Foundation and John

Analytical and clinical performance of the Hologic Aptima HCV Quant Dx Assay for the quantification of HCV RNA in plasma samples.

PubMed

Schønning, Kristian; Pedersen, Martin Schou; Johansen, Kim; Landt, Bodil; Nielsen, Lone Gilmor; Weis, Nina; Westh, Henrik

2017-10-01

Chronic hepatitis C virus (HCV) infection can be effectively treated with directly acting antiviral (DAA) therapy. Measurement of HCV RNA is used to evaluate patient compliance and virological response during and after treatment. To compare the analytical performance of the Aptima HCV Quant Dx Assay (Aptima) and the COBAS Ampliprep/COBAS TaqMan HCV Test v2.0 (CAPCTMv2) for the quantification of HCV RNA in plasma samples, and compare the clinical utility of the two tests in patients undergoing treatment with DAA therapy. Analytical performance was evaluated on two sets of plasma samples: 125 genotyped samples and 172 samples referred for quantification of HCV RNA. Furthermore, performance was evaluated using dilutions series of four samples containing HCV genotype 1a, 2b, 3a, and 4a, respectively. Clinical utility was evaluated on 118 plasma samples obtained from 13 patients undergoing treatment with DAAs. Deming regression of results from 187 plasma samples with HCV RNA >2 Log IU/mL indicated that the Aptima assay quantified higher than the CAPCTMv2 test for HCV RNA >4.9 Log IU/mL. The linearity of the Aptima assay was excellent across dilution series of four HCV genotypes (slope of the regression line: 1.00-1.02). The Aptima assay detected significantly more replicates below targeted 2 Log IU/mL than the CAPCTMv2 test, and yielded clearly interpretable results when used to analyze samples from patients treated with DAAs. The analytical performance of the Aptima assay makes it well suited for monitoring patients with chronic HCV infection undergoing antiviral treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Oligonucleotides as antivirals: dream or realistic perspective?

PubMed

Van Aerschot, Arthur

2006-09-01

Many reports have been published on antiviral activity of synthetic oligonucleotides, targeted to act either by a true antisense effect or via non-sequence specific interactions. This short review will try to evaluate the current status of the field by focusing on the effects as reported for inhibition of either HSV-1, HCMV or HIV-1. Following an introduction with a historical background and a brief discussion on the different types of constructs and mechanisms of action, the therapeutic potential of antisense oligonucleotides as antivirals, as well as possible pitfalls upon their evaluation will be discussed.

Healthcare Costs for Chronic Hepatitis C in South Korea from 2009 to 2013: An Analysis of the National Health Insurance Claims' Data.

PubMed

Ki, Moran; Choi, Hwa Young; Kim, Kyung-Ah; Jang, Eun Sun; Jeong, Sook-Hyang

2017-11-15

The introduction of direct-acting antivirals (DAA) in 2013 revolutionized hepatitis C virus (HCV) treatment, offering a cure rate >90%. However, this therapy is expensive, and estimations of the number of chronic HCV-infected (CHC) patients and their treatment costs pre-2013 are therefore essential for creating policies and expanding drug access. Herein, we aimed to investigate the number of HCV-related liver disease patients, their healthcare utilization, their annual direct medical costs, and the interferon-based antiviral treatment rates and costs from 2009 to 2013 in South Korea. The National Health Insurance database was reviewed, and patients diagnosed with CHC from 2009 to 2013 were extracted. Data regarding detailed healthcare utilization, prescribed drugs, and direct medical costs were obtained. For annual direct healthcare cost calculations, a prevalence-based approach was used. Overall, 181,768 CHC patients were identified. In 2013, the annual per-patient costs for chronic hepatitis, liver cirrhosis, hepatocellular carcinoma, and the first year post-liver transplant were 895, 1,873, 6,945, and 67,359 United States dollars, respectively. Interferon-based antiviral therapeutics were prescribed to 25,223 patients (13.9%). Healthcare costs have increased remarkably with increasing liver disease severity. Thus, efforts to stop disease progression are needed. Moreover, the low rate of interferon-based therapy indicates an unmet need for DAA.

Coinjection of a vaccine and anti-viral agents can provide fast-acting protection from foot-and-mouth disease.

PubMed

You, Su-Hwa; Kim, Taeseong; Choi, Joo-Hyung; Park, Gundo; Lee, Kwang-Nyeong; Kim, Byounghan; Lee, Myoung-Heon; Kim, Hyun-Soo; Kim, Su-Mi; Park, Jong-Hyeon

2017-07-01

Foot-and-mouth disease (FMD) is the cause of an economically devastating animal disease. With commercial inactivated FMD vaccines, the protection against FMD virus (FMDV) begins a minimum of 4 days post vaccination (dpv). Therefore, antiviral agents could be proposed for rapid protection and to reduce the spread of FMDV during outbreaks until vaccine-induced protective immunity occurs. In previous studies, we have developed two recombinant adenoviruses that simultaneously express porcine interferon-α and interferon-γ (Ad-porcine IFN-αγ) and multiple siRNAs that target the non-structural protein-regions of FMDV (Ad-3siRNA), and we have shown that the combination of the two antiviral agents (referred to here as Ad combination) induced robust protection against FMDV in pigs. In an attempt to provide complete protection against FMDV, we co-administered Ad combination and the FMD vaccine to mice and pigs. In the C57BL/6 mice model, we observed rapid and continuous protection against homologous FMDV challenge from 1 to 3 dpv-the period in which vaccine-mediated immunity is absent. In the pig experiments, we found that most of the pigs (five out of six) that received vaccine + Ad combination and were challenged with FMDV at 1 or 2 dpv were clinically protected from FMDV. In addition, most of the pigs that received vaccine + Ad combination and all pigs inoculated with the vaccine only were clinically protected from an FMDV challenge at 7 dpv. We believe that the antiviral agent ensures early protection from FMDV, and the vaccine participates in protection after 7 dpv. Therefore, we can say that the combination of the FMD vaccine and effective antiviral agents may offer both fast-acting and continuous protection against FMDV. In further studies, we plan to design coadministration of Ad combination and novel vaccines. Copyright © 2017 Elsevier B.V. All rights reserved.

Successful Management of Graft Reinfection of HCV Genotype 2 in Living Donor Liver Transplantation from a Hepatitis B Core Antibody-Positive Donor with Sofosbuvir and Ribavirin

PubMed Central

Sasaki, Reina; Kanda, Tatsuo; Ohtsuka, Masayuki; Yasui, Shin; Haga, Yuki; Nakamura, Masato; Yokoyama, Masayuki; Wu, Shuang; Nakamoto, Shingo; Arai, Makoto; Maruyama, Hitoshi; Miyazaki, Masaru; Yokosuka, Osamu

2016-01-01

Direct-acting antivirals (DAAs) are relatively safe and highly effective for the eradication of hepatitis C virus (HCV) in liver transplant recipients. In this case study, we present a female with a graft reinfected with HCV genotype 2 who was treated with a combination of sofosbuvir and ribavirin after living donor liver transplantation (LDLT). Because the graft was from a hepatitis B core antibody-positive donor, passive immunization with hyperimmune hepatitis B immunoglobulin (HBIG) and entecavir were also provided to prevent hepatitis B virus (HBV) reactivation. It became clear that the combination of sofosbuvir and ribavirin promptly led to a sustained virologic response and that this combination was safe to treat graft reinfection with HCV genotype 2 after LDLT. Adverse events caused by DAAs were not observed, except for slight anemia. HBIG and entecavir were useful in the prevention of HBV reactivation. In conclusion, the present case indicated that DAA treatment for graft reinfection with HCV is safe and effective in LDLT from hepatitis B core antibody-positive donors. PMID:27721720

Rapid liver and spleen stiffness improvement in compensated advanced chronic liver disease patients treated with oral antivirals.

PubMed

Pons, Mònica; Santos, Begoña; Simón-Talero, Macarena; Ventura-Cots, Meritxell; Riveiro-Barciela, Mar; Esteban, Rafael; Augustin, Salvador; Genescà, Joan

2017-08-01

We aimed to investigate the early changes in liver and spleen stiffness measurement (LSM, SSM) in hepatitis C virus (HCV) patients with compensated advanced chronic liver disease (cACLD) treated with new antivirals (DAA) to elucidate factors determining the initial change in stiffness and its implications for the long-term follow up of HCV-cured patients. A total of 41 patients with cACLD who started DAA therapy underwent LSM and SSM at baseline, week 4, end of treatment (EOT), 24 and 48 weeks of follow up using transient elastography. LSM improved rapidly during the first 4 weeks of treatment (baseline: 20.8kPa; week 4: 17.5kPa, p = 0.002), with no significant changes between week 4 and EOT (18.3kPa, p = 0.444) and between EOT and 48-week follow up (14.3kPa, p = 0.148). Likewise, SSM improved rapidly (baseline: 45.7kPa; week 4: 33.8kPa, p = 0.047), with no significant changes between week 4 and EOT (30.8kPa, p = 0.153) and between EOT and 48-week follow up (31.2kPa, p = 0.317). A higher decrease in LSM was observed in patients with baseline ALT ⩾ twofold upper limit normal (2 × ULN) than in those with ALT < 2 × ULN (-5.7kPa versus -1.6kPa). Patients who presented a decrease in LSM ⩾ 10% during treatment compared with those with LSM < 10% decrease, showed lower SSM values, higher platelet counts and lower bilirubin levels at 24-week follow up. Those with decrease in SSM ⩾ 10%, presented a higher increase in platelets than those with SSM < 10% change ( p = 0.015). LSM and SSM decrease very rapidly during DAA treatment in cACLD patients suggesting that it most probably reflects a reduction in inflammation rather than in fibrosis. cACLD patients should be maintained under surveillance independently of stiffness changes, because advanced fibrosis can still be present.

Immunosuppressive and antiviral treatment of hepatitis C virus-associated glomerular disease: A long-term follow-up.

PubMed

Fabrizi, Fabrizio; Aghemo, Alessio; Lampertico, Pietro; Fraquelli, Mirella; Cresseri, Donata; Moroni, Gabriella; Passerini, Patrizia; Donato, Francesca M; Messa, Piergiorgio

2018-06-01

The evidence in the medical literature on the treatment of hepatitis C virus-associated glomerular disease is extremely limited. The advent of nonconventional immunosuppressive agents and direct-acting antivirals promises high efficacy and safety. We conducted an open-label, single-arm clinical study to examine the efficacy and safety of a combined approach for hepatitis C virus-associated glomerular disease. In the first phase of the study, patients with hepatitis C virus-associated glomerular disease received interferon-based antiviral therapy and immunosuppressive agents; since 2013, interferon-free antiviral therapy was adopted and novel immunosuppressants (including B-cell depleting agents and mycophenolate mofetil) or immunomodulators (ribavirin) were choiced. Virological and clinical responses were evaluated over a long observation period (median follow-up of 60 weeks and 46.5 months after the end of treatment with interferon and direct-acting antiviral agents, respectively). We enrolled 25 consecutive patients with hepatitis C virus-associated glomerular disease, 8 being liver transplant recipients for hepatitis C. A total of 13 patients received therapy with direct-acting antivirals and experienced sustained viral response (serum hepatitis C virus RNA <12 IU/mL, 12 weeks after treatment ended, sustained viral response12). The mean (±standard deviation) proteinuria decreased from 2.61 ± 1.01 at baseline to 1.71 ± 1.43 (g/day) at sustained viral response 48, p = 0.031; microscopic hematuria and serum cryoglobulins disappeared in six (50%) and seven (64%) patients, respectively, after sustained viral response by direct-acting antivirals. Adverse events occurred in 69% (9/13) of patients and were mild, with four cases of ribavirin-related anemia requiring blood transfusions (no drop-outs). After sustained viral response by direct-acting antivirals, immunosuppressive and immunomodulatory agents were initiated in clinical relapsers ( n = 2) and nonresponders

Baseline NS5A resistance associated substitutions may impair DAA response in real-world hepatitis C patients.

PubMed

Carrasco, Itzíar; Arias, Ana; Benítez-Gutiérrez, Laura; Lledó, Gemma; Requena, Silvia; Cuesta, Miriam; Cuervas-Mons, Valentín; de Mendoza, Carmen

2018-03-01

Oral DAA have demonstrated high efficacy as treatment of hepatitis C. However, the presence of resistance-associated substitutions (RAS) at baseline has occasionally been associated with impaired treatment response. Herein, we examined the impact of baseline RAS at the HCV NS5A gene region on treatment response in a real-life setting. All hepatitis C patients treated with DAA including NS5A inhibitors at our institution were retrospectively examined. The virus NS5A gene was analyzed using population sequencing at baseline and after 24 weeks of completing therapy in all patients that failed. All changes recorded at positions 28, 29, 30, 31, 32, 58, 62, 92, and 93 were considered. A total of 166 patients were analyzed. HCV genotypes were as follows: G1a (31.9%), G1b (48.2%), G3 (10.2%), and G4 (9.6%). Overall, 69 (41.6%) patients were coinfected with HIV and 46.7% had advanced liver fibrosis (Metavir F3-F4). Sixty (36.1%) patients had at least one RAS at baseline, including M28A/G/T (5), Q30X (12), L31I/F/M/V (6), T58P/S (25), Q/E62D (1), A92 K (7), and Y93C/H (15). Overall, 4.8% had two or more RAS, being more frequent in G4 (12.5%) followed by G1b (6.3%) and G1a (1.9%). Of 10 (6%) patients that failed DAA therapy, five had baseline NS5A RAS. No association was found for specific baseline RAS, although changes at position 30 were more frequent in failures than cures (22.2% vs 6.4%, P = 0.074). Moreover, the presence of two or more RAS at baseline was more frequent in failures (HR: 7.2; P = 0.029). Upon failure, six patients showed emerging RAS, including Q30C/H/R (3), L31M (1), and Y93C/H (2). Baseline NS5A RAS are frequently seen in DAA-naïve HCV patients. Two or more baseline NS5A RAS were found in nearly 5% and were significantly associated to DAA failure. Therefore, baseline NS5A testing should be considered when HCV treatment is planned with NS5A inhibitors. © 2017 Wiley Periodicals, Inc.

Perspective of Use of Antiviral Peptides against Influenza Virus

PubMed Central

Skalickova, Sylvie; Heger, Zbynek; Krejcova, Ludmila; Pekarik, Vladimir; Bastl, Karel; Janda, Jozef; Kostolansky, Frantisek; Vareckova, Eva; Zitka, Ondrej; Adam, Vojtech; Kizek, Rene

2015-01-01

The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20th century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides. PMID:26492266

Real-world virological efficacy and safety of elbasvir and grazoprevir in patients with chronic hepatitis C virus genotype 1 infection in Japan.

PubMed

Toyoda, Hidenori; Atsukawa, Masanori; Takaguchi, Koichi; Senoh, Tomonori; Michitaka, Kojiro; Hiraoka, Atsushi; Fujioka, Shinichi; Kondo, Chisa; Okubo, Tomomi; Uojima, Haruki; Tada, Toshifumi; Yoneyama, Hirohito; Watanabe, Tsunamasa; Asano, Toru; Ishikawa, Toru; Tamai, Hideyuki; Abe, Hiroshi; Kato, Keizo; Tsuji, Kunihiko; Ogawa, Chikara; Shimada, Noritomo; Iio, Etsuko; Deguchi, Akihiro; Itobayashi, Ei; Mikami, Shigeru; Moriya, Akio; Okubo, Hironao; Tani, Joji; Tsubota, Akihito; Tanaka, Yasuhito; Masaki, Tsutomu; Iwakiri, Katsuhiko; Kumada, Takashi

2018-05-08

The real-world virological efficacy and safety of an interferon (IFN)-free direct-acting antiviral (DAA) therapy with elbasvir (EBR) and grazoprevir (GZR) were evaluated in Japanese patients chronically infected with hepatitis C virus (HCV) genotype 1. The rate of sustained virologic response (SVR) and safety were analyzed in patients who started the EBR/GZR regimen between November 2016 and July 2017. SVR rates were compared based on patient baseline characteristics. Overall, 371 of 381 patients (97.4%) achieved SVR. Multivariate analysis identified a history of failure to IFN-free DAA therapy and the presence of double resistance-associated substitutions (RASs) in HCV non-structural protein 5A (NS5A) as factors significantly associated with failure to EBR/GZR treatment. The SVR rates of patients with a history of IFN-free DAA therapy and those with double RASs were 55.6 and 63.6%, respectively. In all other subpopulations, the SVR rates were more than 90%. There were no severe adverse events associated with the treatment. The EBR/GZR regimen yielded high virological efficacy with acceptable safety. Patients with a history of failure to IFN-free DAA therapy or with double RASs in HCV-NS5A remained difficult to treat with this regimen.

Impact of different sofosbuvir based treatment regimens on the biochemical profile of chronic hepatitis C genotype 4 patients.

PubMed

Elsharkawy, Aisha; Eletreby, Rasha; Fouad, Rabab; Soliman, Zeinab; Abdallah, Mohamed; Negm, Mohamed; Mohey, Mohammad; Esmat, Gamal

2017-08-01

Huge efforts have been made to control chronic HCV in Egypt with introduction of Direct-Acting Antivirals (DAAs). Current study aims at evaluating effect of various DAA regimens on liver biochemical profile and haematological indices during treatment. 272 patients with chronic HCV genotype 4 treated by different DAA regimens (SOF/RBV, SOF/DAC ± RBV, SOF/SIM) for a duration of 12 or 24 weeks in Kasr Alainy Viral Hepatitis Center, Cairo University were followed up for serum bilirubin (BIL), albumin (ALB), alanine transaminase (ALT), aspartate aminotransferase (AST), prothrombin concentration, international normalized ratio (INR), and CBC at baseline, week-4 and end of treatment. Mean age was 54 years. Males comprised 64.7%, 72.4% were treatment-naïve, 39% were cirrhotic. Overall SVR12 rate was (93.4%). With all regimens, ALT and AST declined after treatment. In cirrhotics, there was a rise in BIL and INR; with no change in ALB and a decrease in White blood cells. Drop in Hemoglobin and platelets in cirrhotic patients were noted with SOF/RBV, while SOF/SIM showed rise in BIL. DAAs are safe and effective in genotype 4 chronic HCV patients. It improves liver necro-inflammatory markers in cirrhotics and non-cirrhotics. Cirrhotic patients require careful observation being more vulnerable for treatment related complications.

Prevalence of naturally occurring NS5A resistance-associated substitutions in patients infected with hepatitis C virus subtype 1a, 1b, and 3a, co-infected or not with HIV in Brazil.

PubMed

Malta, Fernanda; Gaspareto, Karine Vieira; Lisboa-Neto, Gaspar; Carrilho, Flair José; Mendes-Correa, Maria Cássia; Pinho, João Renato Rebello

2017-11-13

Non-structural 5A protein (NS5A) resistance-associated substitutions (RASs) have been identified in patients infected with hepatitis C virus (HCV), even prior to exposure to direct-acting antiviral agents (DAAs). Selection for these variants occurs rapidly during treatment and, in some cases, leads to antiviral treatment failure. DAAs are currently the standard of care for hepatitis C treatment in many parts of the world. Nevertheless, in Brazil, the prevalence of pre-existing NS5A RASs is largely unknown. In this study, we evaluated the frequency of naturally occurring NS5A RASs in Brazilian patients infected with HCV as either a monoinfection or coinfection with human immunodeficiency virus (HIV). Direct Sanger sequencing of the NS5A region was performed in 257 DAA-naïve patients chronically infected with HCV (156 monoinfected with HCV and 101 coinfected with HIV/HCV). The frequencies of specific RASs in monoinfected patients were 14.6% for HCV GT-1a (M28 V and Q30H/R), 6.0% for GT-1b (L31F/V and Y93H), and 22.6% for GT-3a (A30K and Y93H). For HIV/HCV-coinfected patients, the frequencies of RAS were 3.9% for GT-1a (M28 T and Q30H/R), and 11.1% for GT-1b (Y93H); no RASs were found in GT-3a sequences. Substitutions that may confer resistance to NS5A inhibitors exist at baseline in Brazilian DAA-naïve patients infected with HCV GT-1a, -1b, and -3a. Standardization of RAS definitions is needed to improve resistance analyses and to facilitate comparisons of substitutions reported across studies worldwide. Therapeutic strategies should be optimized to efficiently prevent DAA treatment failure due to selection for RASs, especially in difficult-to-cure patients.

The antiviral activity of arctigenin in traditional Chinese medicine on porcine circovirus type 2.

PubMed

Chen, Jie; Li, Wentao; Jin, Erguang; He, Qigai; Yan, Weidong; Yang, Hanchun; Gong, Shiyu; Guo, Yi; Fu, Shulin; Chen, Xiabing; Ye, Shengqiang; Qian, Yunguo

2016-06-01

Arctigenin (ACT) is a phenylpropanoid dibenzylbutyrolactone lignan extracted from the traditional herb Arctium lappa L. (Compositae) with anti-viral and anti-inflammatory effects. Here, we investigated the antiviral activity of ACT found in traditional Chinese medicine on porcine circovirus type 2 (PCV2) in vitro and in vivo. Results showed that dosing of 15.6-62.5μg/mL ACT could significantly inhibit the PCV2 proliferation in PK-15 cells (P<0.01). Dosing of 62.5μg/mL ACT 0, 4 or 8h after challenge inoculation significantly inhibited the proliferation of 1MOI and 10MOI in PK-15 cells (P<0.01), and the inhibitory effect of ACT dosing 4h or 8h post-inoculation was greater than 0h after dosing (P<0.01). In vivo test with mice challenge against PCV2 infection demonstrated that intraperitoneal injection of 200μg/kg ACT significantly inhibited PCV2 proliferation in the lungs, spleens and inguinal lymph nodes, with an effect similar to ribavirin, demonstrating the effectiveness of ACT as an antiviral agent against PCV2 in vitro and in vivo. This compound, therefore, may have the potential to serve as a drug for protection of pigs against the infection of PCV2. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cost-effectiveness and budget impact of interferon-free direct-acting antiviral-based regimens for hepatitis C treatment: the French case.

PubMed

Deuffic-Burban, S; Obach, D; Canva, V; Pol, S; Roudot-Thoraval, F; Dhumeaux, D; Mathurin, P; Yazdanpanah, Y

2016-10-01

We evaluated the cost-effectiveness and the budget impact of new DAA-based regimen use in France. A Markov model simulated chronic hepatitis C (CHC) treatment interventions with IFN-based and IFN-free regimens at stage of fibrosis ≥F3, ≥F2 or regardless of fibrosis stage, and treatment either with the least or the most expensive combination. It estimated quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs). It also assessed the budget impact over 5 years of treating all CHC-screened patients, regardless of fibrosis, assuming ≤20 000 patients treated/year and priority to ≥F3. Sensitivity analyses were also conducted. For genotypes (G) 1-4, the initiation of IFN-free regardless of fibrosis was a cost-effective strategy compared to prior standard of care (SOC) initiated at stage F2: €40 400-88 300/QALY gained in G1; similar results were obtained for patients infected with G4. Considering G2-3, the most cost-effective strategy was IFN-based regimens regardless of fibrosis compared to prior SOC initiated at stage F2: €21 300 and €19 400/QALY gained, respectively; the strategy with IFN-free regimens being more effective but not cost-effective at current costs. The budget impact of treating all CHC-screened patients over 5 years would range between 3.5 and 7.2 billion €, depending on whether one considers the least or the most expensive combination of new DAAs and whether one treats G2-3 with IFN-based or IFN-free new DAAs. In France, treatment initiation with new DDAs regardless of fibrosis stage is cost-effective, but would add 3.5-7.2 billion € to an already overburdened medical care system. © 2016 John Wiley & Sons Ltd.

Hepatitis C and liver transplantation.

PubMed

Martini, Silvia

2018-06-01

Hepatitis C virus (HCV)-related liver disease represents the leading indication for liver transplantation (LT) in the USA and Europe and HCV recurrence is universal in recipients who are viremic at LT. Until a few years ago, pegylated-interferon in association with ribavirin was the only therapeutic strategy, usable only in compensated cirrhotic patients, in order to prevent post-LT viral recurrence. The recent advent of direct-acting antiviral agents (DAAs) has dramatically increased the chances of curative treatment for the transplant population and the debate about which should be the best time for treating the infection is still open: whether to pursue HCV eradication 1) before LT, in order to improve liver function, delist some patients and prevent graft infection; or 2) as early as possible after LT, rather than 3) waiting for hepatitis C recurrence before starting treatment. In addition, in the DAA era, the use of HCV-positive donors may represent a potential approach to safely expanding the donor pool. As more HCV patients achieve cure with DAA regimens, the LT trend for HCV in the future would be expected to mimic the trend observed for hepatitis B virus in the past decade and in the United States, during the DAA-period 2014-2015, the rate of LT wait-listing for HCV complicated by decompensated cirrhosis has already decreased by 32%. This review summarizes the published data and emphasizes DAA treatment applicability to patients with decompensated cirrhosis and to liver transplant recipients.

Delisting HCV-infected liver transplant candidates who improved after viral eradication: Outcome 2 years after delisting.

PubMed

Perricone, Giovanni; Duvoux, Christophe; Berenguer, Marina; Cortesi, Paolo A; Vinaixa, Carmen; Facchetti, Rita; Mazzarelli, Chiara; Rockenschaub, Susanne-Rasoul; Martini, Silvia; Morelli, Cristina; Monico, Sara; Volpes, Riccardo; Pageaux, Georges-Philippe; Fagiuoli, Stefano; Belli, Luca S

2018-05-11

Treating patients with decompensated cirrhosis with direct-acting antiviral (DAA) therapy while on the waiting list for liver transplantation results in substantial improvement of liver function allowing 1 in 4 patients to be removed from the waiting list or delisted, as reported in a previous study promoted by the European Liver and Intestine Transplant Association (ELITA). The aim of this study was to report on clinical outcomes of delisted patients, including mortality risk, hepatocellular carcinoma development and clinical decompensation requiring relisting. One hundred and forty-two HCV-positive patients on the liver transplant waiting list for decompensated cirrhosis, negative for hepatocellular carcinoma, between February 2014 and June 2015 were treated with DAA therapy and were prospectively followed up. Forty-four patients (30.9%) were delisted following clinical improvement. This percentage was higher than in the original study because of a number of patients being delisted long after starting DAAs. The median Child-Pugh and MELD score of delisted patients was 5.5 and 9 respectively. Four patients were relisted, because of HCC diagnosis in 1 case and 3 patients developed ascites. One further patient died (2.4%) because of rapidly progressing hepatocellular carcinoma twenty-two months after delisting. Of the 70 patients who received a liver graft, 9 died (13%). Antiviral therapy allows for a long-term improvement of liver function and the delisting of one-third of treated patients with risk of liver-related complications after delisting being very low. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fast hepatitis C virus RNA elimination and NS5A redistribution by NS5A inhibitors studied by a multiplex assay approach.

PubMed

Liu, Dandan; Ji, Juan; Ndongwe, Tanya P; Michailidis, Eleftherios; Rice, Charles M; Ralston, Robert; Sarafianos, Stefan G

2015-01-01

While earlier therapeutic strategies for the treatment of hepatitis C virus (HCV) infection relied exclusively on interferon (IFN) and ribavirin (RBV), four direct-acting antiviral agents (DAAs) have now been approved, aiming for an interferon-free strategy with a short treatment duration and fewer side effects. To facilitate studies on the mechanism of action (MOA) and efficacy of DAAs, we established a multiplex assay approach, which employs flow cytometry, a Gaussia luciferase reporter system, Western blot analysis, reverse transcription-quantitative PCR (RT-qPCR), a limited dilution assay (50% tissue culture infectious dose [TCID50]), and an image profiling assay that follows the NS5A redistribution in response to drug treatment. We used this approach to compare the relative potency of various DAAs and the kinetics of their antiviral effects as a potential preclinical measure of their potential clinical utility. We evaluated the NS5A inhibitors ledipasvir (LDV) and daclatasvir (DCV), the NS3/4A inhibitor danoprevir (DNV), and the NS5B inhibitor sofosbuvir (SOF). In terms of kinetics, our data demonstrate that the NS5A inhibitor LDV, followed closely by DCV, has the fastest effect on suppression of viral proteins and RNA and on redistribution of NS5A. In terms of MOA, LDV has a more pronounced effect than DCV on the viral replication, assembly, and infectivity of released virus. Our approach can be used to facilitate the study of the biological processes involved in HCV replication and help identify optimal drug combinations. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Naturally occurring NS3 resistance-associated variants in hepatitis C virus genotype 1: Their relevance for developing countries.

PubMed

Echeverría, Natalia; Betancour, Gabriela; Gámbaro, Fabiana; Hernández, Nelia; López, Pablo; Chiodi, Daniela; Sánchez, Adriana; Boschi, Susana; Fajardo, Alvaro; Sóñora, Martín; Moratorio, Gonzalo; Cristina, Juan; Moreno, Pilar

2016-09-02

Hepatitis C virus (HCV) is a major cause of global morbidity and mortality, with an estimated 130-150 million infected individuals worldwide. HCV is a leading cause of chronic liver diseases including cirrhosis and hepatocellular carcinoma. Current treatment options in developing countries involve pegylated interferon-α and ribavirin as dual therapy or in combination with one or more direct-acting antiviral agents (DAA). The emergence of resistance-associated variants (RAVs) after treatment reveals the great variability of this virus leading to a great difficulty in developing effective antiviral strategies. Baseline RAVs detected in DAA treatment-naïve HCV-infected patients could be of great importance for clinical management and outcome prediction. Although the frequency of naturally occurring HCV NS3 protease inhibitor mutations has been addressed in many countries, there are only a few reports on their prevalence in South America. In this study, we investigated the presence of RAVs in the HCV NS3 serine protease region by analysing a cohort of Uruguayan patients with chronic hepatitis C who had not been treated with any DAAs and compare them with the results found for other South American countries. The results of these studies revealed that naturally occurring mutations conferring resistance to NS3 inhibitors exist in a substantial proportion of Uruguayan treatment-naïve patients infected with HCV genotype 1 enrolled in these studies. The identification of these baseline RAVs could be of great importance for patients' management and outcome prediction in developing countries. Copyright © 2016 Elsevier B.V. All rights reserved.

Antiviral RNA Recognition and Assembly by RLR Family Innate Immune Sensors

PubMed Central

Bruns, Annie M.; Horvath, Curt M.

2014-01-01

Virus-encoded molecular signatures, such as cytosolic double-stranded or otherwise biochemically distinct RNA species, trigger cellular antiviral signaling. Cytoplasmic proteins recognize these non-self RNAs and activate signal transduction pathways that drive the expression of virus-induced genes, including the primary antiviral cytokine, IFNβ, and diverse direct and indirect antiviral effectors [1–4]. One important group of cytosolic RNA sensors known as the RIG-I like receptors (RLRs) is comprised of three proteins that are similar in structure and function. The RLR proteins, RIG-I, MDA5, and LGP2, share the ability to recognize nucleic acid signatures produced by virus infections and activate antiviral signaling. Emerging evidence indicates that RNA detection by RLRs culminates in the assembly of dynamic multimeric ribonucleoprotein (RNP) complexes. These RNPs can act as signaling platforms that are capable of propagating and amplifying antiviral signaling responses. Despite their common domain structures and similar abilities to induce antiviral responses, the RLRs differ in their enzymatic properties, their intrinsic abilities to recognize RNA, and their ability to assemble into filamentous complexes. This molecular specialization has enabled the RLRs to recognize and respond to diverse virus infections, and to mediate both unique and overlapping functions in immune regulation [5, 6]. PMID:25081315

Availability of hepatitis C diagnostics and therapeutics in European and Eurasia countries.

PubMed

Leblebicioglu, Hakan; Arends, Joop E; Ozaras, Resat; Corti, Giampaolo; Santos, Lurdes; Boesecke, Christoph; Ustianowski, Andrew; Duberg, Ann-Sofi; Ruta, Simona; Salkic, Nermin N; Husa, Petr; Lazarevic, Ivana; Pineda, Juan A; Pshenichnaya, Natalia Yurievna; Tsertswadze, Tengiz; Matičič, Mojca; Puca, Edmond; Abuova, Gulzhan; Gervain, Judit; Bayramli, Ramin; Ahmeti, Salih; Koulentaki, Mairi; Kilani, Badreddine; Vince, Adriana; Negro, Francesco; Sunbul, Mustafa; Salmon, Dominique

2018-02-01

Treatment with direct acting antiviral agents (DAAs) has provided sustained virological response rates in >95% of patients with chronic hepatitis C virus (HCV) infection. However treatment is costly and market access, reimbursement and governmental restrictions differ among countries. We aimed to analyze these differences among European and Eurasian countries. A survey including 20-item questionnaire was sent to experts in viral hepatitis. Countries were evaluated according to their income categories by the World Bank stratification. Experts from 26 countries responded to the survey. As of May 2016, HCV prevalence was reported as low (≤1%) in Croatia, Czech Republic, Denmark, France, Germany, Hungary, the Netherlands, Portugal, Slovenia, Spain, Sweden, UK; intermediate (1-4%) in Azerbaijan, Bosnia and Herzegovina, Italy, Kosovo, Greece, Kazakhstan, Romania, Russia, Serbia and high in Georgia (6.7%). All countries had national guidelines except Albania, Kosovo, Serbia, Tunisia, and UK. Transient elastography was available in all countries, but reimbursed in 61%. HCV-RNA was reimbursed in 81%. PegIFN/RBV was reimbursed in 54% of the countries. No DAAs were available in four countries: Kazakhstan, Kosovo, Serbia, and Tunisia. In others, at least one DAA combination with either PegIFN/RBV or another DAA was available. In Germany and the Netherlands all DAAs were reimbursed without restrictions: Sofosbuvir and sofosbuvir/ledipasvir were free of charge in Georgia. Prevalence of HCV is relatively higher in lower-middle and upper-middle income countries. DAAs are not available or reimbursed in many Eurasia and European countries. Effective screening and access to care are essential for reducing liver-related morbidity and mortality. Copyright © 2017 Elsevier B.V. All rights reserved.

Curing Chronic Hepatitis C: A Cost Comparison of the Combination Simeprevir Plus Sofosbuvir vs. Protease-Inhibitor-Based Triple Therapy.

PubMed

Langness, Jacob A; Tabano, David; Wieland, Amanda; Tise, Sarah; Pratt, Lindsay; Harrington, Lauren Ayres; Lin, Sonia; Ghuschcyan, Vahram; Nair, Kavita V; Everson, Gregory T

Interferon-free, multi-direct acting antiviral (DAA) therapy for chronic hepatitis C virus (HCV) infection is highly effective and well tolerated, but costly. To gain perspective on the evolving economics of HCV therapy, we compared the cost per cure of a multi-DAA regimen with the prior standard of triple therapy. Patients infected with HCV genotype 1 who were treated through the University of Colorado Hepatology Clinic between May 2011 and December 2014 comprised the study population. The multi-DAA regimen of simeprevir plus sofosbuvir (SMV/SOF) was compared to the triple therapy regimen consisting of peginterferon and ribavirin, with either boceprevir or telaprevir (TT). Sustained-virologic response (SVR) rates, total costs per treatment and adverse events were recorded. Total cost per SVR were compared for the two treatments, controlling for patient demographics and clinical characteristics. One hundred eighty-three patients received SMV/SOF (n = 70) or TT (n = 113). Patients receiving SMV/SOF were older, more treatment experienced, and had a higher stage of fibrosis. SVRs were 86% and 59%, average total costs per patient were $152,775 and $95,943, and average total costs per SVR were $178,237 vs. $161,813.49 for SMV/SOF and TT groups, respectively. Medication costs accounted for 98% of SMV/SOF and 85% of TT treatment costs. The high cure rate of multi-DAA treatment of HCV is offset by the high costs of the DAAs, such that the cost per cure from TT to multi-DAA therapy has been relatively constant. In order to cure more patients, either additional financial resources will need to be allocated to the treatment of HCV or drug costs will need to be reduced.

The Antiviral Drug Arbidol Inhibits Zika Virus.

PubMed

Fink, Susan L; Vojtech, Lucia; Wagoner, Jessica; Slivinski, Natalie S J; Jackson, Konner J; Wang, Ruofan; Khadka, Sudip; Luthra, Priya; Basler, Christopher F; Polyak, Stephen J

2018-06-12

There are many emerging and re-emerging globally prevalent viruses for which there are no licensed vaccines or antiviral medicines. Arbidol (ARB, umifenovir), used clinically for decades in several countries as an anti-influenza virus drug, inhibits many other viruses. In the current study, we show that ARB inhibits six different isolates of Zika virus (ZIKV), including African and Asian lineage viruses in multiple cell lines and primary human vaginal and cervical epithelial cells. ARB protects against ZIKV-induced cytopathic effects. Time of addition studies indicate that ARB is most effective at suppressing ZIKV when added to cells prior to infection. Moreover, ARB inhibits pseudoviruses expressing the ZIKV Envelope glycoprotein. Thus, ARB, a broadly acting anti-viral agent with a well-established safety profile, inhibits ZIKV, likely by blocking viral entry.

Assessment of Inhibition of Ebola Virus Progeny Production by Antiviral Compounds.

PubMed

Falzarano, Darryl

2017-01-01

Assessment of small molecule compounds against filoviruses, such as Ebola virus, has identified numerous compounds that appear to have antiviral activity and should presumably be further investigated in animal efficacy trials. However, despite the many compounds that are purported to have good antiviral activity in in vitro studies, there are few instances where any efficacy has been reported in nonhuman primate models. Many of the high-throughput screening assays use reporter systems that only recapitulate a portion of the virus life cycle, while other assays only assess antiviral activity at relatively early time points. Moreover, many assays do not assess virus progeny production. A more in-depth evaluation of small numbers of test compounds is useful to economize resources and to generate higher quality antiviral hits. Assessing virus progeny production as late as 5 days post-infection allows for the elimination of compounds that have initial antiviral effects that are not sustained or where the virus rapidly develops resistance. While this eliminates many potential lead compounds that may be worthy of further structure-activity relationship (SAR) development, it also quickly excludes compounds that in their current form are unlikely to be effective in animal models. In addition, the inclusion of multiple assays that assess both cell viability and cell cytotoxicity, via different mechanisms, provides a more thorough assessment to exclude compounds that are not direct-acting antivirals.

Humanisation of a claudin-1-specific monoclonal antibody for clinical prevention and cure of HCV infection without escape.

PubMed

Colpitts, Che C; Tawar, Rajiv G; Mailly, Laurent; Thumann, Christine; Heydmann, Laura; Durand, Sarah C; Xiao, Fei; Robinet, Eric; Pessaux, Patrick; Zeisel, Mirjam B; Baumert, Thomas F

2018-04-01

HCV infection is a leading cause of chronic liver disease and a major indication for liver transplantation. Although direct-acting antivirals (DAAs) have much improved the treatment of chronic HCV infection, alternative strategies are needed for patients with treatment failure. As an essential HCV entry factor, the tight junction protein claudin-1 (CLDN1) is a promising antiviral target. However, genotype-dependent escape via CLDN6 and CLDN9 has been described in some cell lines as a possible limitation facing CLDN1-targeted therapies. Here, we evaluated the clinical potential of therapeutic strategies targeting CLDN1. We generated a humanised anti-CLDN1 monoclonal antibody (mAb) (H3L3) suitable for clinical development and characterised its anti-HCV activity using cell culture models, a large panel of primary human hepatocytes (PHH) from 12 different donors, and human liver chimeric mice. H3L3 pan-genotypically inhibited HCV pseudoparticle entry into PHH, irrespective of donor. Escape was likely precluded by low surface expression of CLDN6 and CLDN9 on PHH. Co-treatment of a panel of PHH with a CLDN6-specific mAb did not enhance the antiviral effect of H3L3, confirming that CLDN6 does not function as an entry factor in PHH from multiple donors. H3L3 also inhibited DAA-resistant strains of HCV and synergised with current DAAs. Finally, H3L3 cured persistent HCV infection in human-liver chimeric uPA-SCID mice in monotherapy. Overall, these findings underscore the clinical potential of CLDN1-targeted therapies and describe the functional characterisation of a humanised anti-CLDN1 antibody suitable for further clinical development to complement existing therapeutic strategies for HCV. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

New therapies for chronic hepatitis C infection: a systematic review of evidence from clinical trials.

PubMed

Lee, L Y; Tong, C Y W; Wong, T; Wilkinson, M

2012-04-01

Hepatitis C virus (HCV) affects approximately 3% of the world population. The current standard of care for treatment of HCV is a combination of pegylated interferon and ribavirin. Approximately 10% of patients will stop treatment and 30% of patients require dose reduction because of side effects. For genotype 1 HCV-infected patients, only 40% of patients will achieve undetectable viral load 26 weeks posttreatment. The objectives of this review were to identify new treatments that are in clinical trials. These include boceprevir and telaprevir which are in routine clinical use and form part of the American Association for the Study of Liver Diseases (AASLD) 2011 guidelines as well as drugs based on observational studies, improving/modifying ribavirin or interferon-based therapies, modifying the host response and finally the use of direct-acting antiviral agents (DAA).   MEDLINE and EMBASE databases were searched from 2008 to 2011 for treatments for hepatitis C. Furthermore, abstracts and poster presentations for the annual European Association Study of the Liver, AASLD, Digestive Disease Week and Asian Pacific Association for the study of the Liver were searched for relevant material. All four classes of DAA; NS3/NS4a serine protease inhibitors, cyclophilin inhibitors, NS5b polymerase inhibitors and NS5a inhibitors, show good success rates. Trials have been performed without ribavirin or interferon and demonstrate good antiviral activity with a decreased side effect profile. Combinations of DAA are a promising area of research with a high success rate. Clinical trials show that future HCV therapy could be personalised, achieve higher success rates with decreased adverse incidents. © 2012 Blackwell Publishing Ltd.

Hepatitis C Virus Clearance in Older Adults.

PubMed

Ippolito, Antonio Massimo; Iacobellis, Angelo; Milella, Michele; Conti, Fabio; Messina, Vincenzo; Valvano, Maria Rosa; Niro, Grazia Anna; Morisco, Filomena; Barone, Michele; Termite, Antonio Patrizio; Brancaccio, Giuseppina; Andriulli, Angelo

2018-01-01

To determine whether older adults with the hepatitis C virus (HCV) achieve a sustained viral response (SVR) after treatment with direct-acting antiviral therapy. Individuals aged 80 and older with chronic HCV infection (N = 253; n = 213 with cirrhosis, n = 40 with advanced fibrosis). We investigated the efficacy, safety, and global clinical effect of treatment with different combinations of direct antiviral agents (DAAs). Participants with cirrhosis were staged according to Child-Pugh-Turcotte class, Model for End-Stage Liver Disease score, and the D'Amico staging system. The type and number of comorbidities at baseline and hepatic and nonhepatic events during follow-up were registered. Ninety-five percent of participants with cirrhosis and 95% of those with advanced fibrosis attained SVR. The rate was independent of sex, HCV genotype, and treatment schedule. During a mean follow-up of 14 ± 4 months (range 5-23 months), 34 events occurred in 27 participants: 10 hepatocellular carcinomas, 12 hepatic decompensations, 9 nonhepatic events, 3 deaths. Multivariate analysis of risk factors for experiencing adverse events during follow up showed that participants in D'Amico Stages 4 and 5, with a baseline serum albumin level of 3.5 mg/dL or less, and 3 or more comorbidities were the most at risk. In a real-world setting, DAAs are safe and effective in older adults with HCV-related advanced fibrosis or cirrhosis. Individuals with preserved albumin synthesis and fewer than 3 comorbidities at baseline have the most to gain from long-term DAA therapy. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Successful treatment of hepatitis C, genotype 3, with sofosbuvir/ledipasvir in decompensated cirrhosis complicated by mixed cryoglobulinaemia

PubMed Central

Flemming, Jennifer A; Lowe, Catherine E

2016-01-01

Advances in the treatment of chronic hepatitis C (HCV) have given HCV providers access to treatment regimens able to achieve sustained virological response (SVR or ‘cure’) in the majority of patients. There are, however, groups of patients in whom HCV treatment outcomes with direct acting antivirals (DAAs) are suboptimal (genotype (GT) 3 patients, decompensated cirrhosis, renal failure) or have not been studied in large cohorts (patients with cryoglobulinaemia (CG)). This case outlines the successful eradication of GT-3 hepatitis C (HCV) in a patient with decompensated cirrhosis and renal failure secondary to mixed CG with DAA failure, using a 12-week course of sofosbuvir, ledipasvir and ribavirin. The achievement of SVR in this patient resulted in significant improvement in hepatic and renal function. Patients with decompensated cirrhosis and GT-3 disease remain a difficult to treat population, and the safety and efficacy of sofosbuvir, ledipasvir and ribavirin in this cohort require further study. PMID:27284099

Successful treatment of hepatitis C, genotype 3, with sofosbuvir/ledipasvir in decompensated cirrhosis complicated by mixed cryoglobulinaemia.

PubMed

Flemming, Jennifer A; Lowe, Catherine E

2016-06-09

Advances in the treatment of chronic hepatitis C (HCV) have given HCV providers access to treatment regimens able to achieve sustained virological response (SVR or 'cure') in the majority of patients. There are, however, groups of patients in whom HCV treatment outcomes with direct acting antivirals (DAAs) are suboptimal (genotype (GT) 3 patients, decompensated cirrhosis, renal failure) or have not been studied in large cohorts (patients with cryoglobulinaemia (CG)). This case outlines the successful eradication of GT-3 hepatitis C (HCV) in a patient with decompensated cirrhosis and renal failure secondary to mixed CG with DAA failure, using a 12-week course of sofosbuvir, ledipasvir and ribavirin. The achievement of SVR in this patient resulted in significant improvement in hepatic and renal function. Patients with decompensated cirrhosis and GT-3 disease remain a difficult to treat population, and the safety and efficacy of sofosbuvir, ledipasvir and ribavirin in this cohort require further study. 2016 BMJ Publishing Group Ltd.

Expanding access to transplantation with hepatitis C-positive donors: A new perspective on an old issue.

PubMed

Kling, Catherine E; Limaye, Ajit P; Landis, Charles S; Sibulesky, Lena

2017-02-01

With the need for organs far exceeding supply, donors previously exposed to hepatitis B (HBV) and hepatitis C (HCV) viral infections should be considered for transplantation. Although many centers have protocols for transplanting organs from HBV core antibody-positive (HBcAb+) donors into select recipients, in the era of direct-acting antivirals (DAAs), a new focus should be placed on HCV-positive donors. The transmission rate from HCV antibody-positive (HCVAb+) nucleic acid testing negative (HCV NAT-) donors is expected to be very low, and we encourage use of such organs in HCV recipients provided a normal biopsy, appropriate counseling, and careful post-transplant monitoring. While transmission of HCV from HCV NAT+ donors is universal, the success of DAA in obtaining a sustained viral response in post-transplant recipients should make the use of these organs more appealing. We herein provide information to help guide the use of organs from HCV donors. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Impact of interferon-free regimens on the glomerular filtration rate during treatment of chronic hepatitis C in a real-life cohort.

PubMed

Álvarez-Ossorio, M J; Sarmento E Castro, R; Granados, R; Macías, J; Morano-Amado, L E; Ríos, M J; Merino, D; Álvarez, E N; Collado, A; Pérez-Pérez, M; Téllez, F; Martín, J M; Méndez, J; Pineda, J A; Neukam, K

2018-06-01

Little data are available on renal toxicity exerted by direct-acting antivirals (DAAs) in real life. The aim of this study was to assess the impact of direct-acting antivirals against hepatitis C virus infection currently used in Spain and Portugal on the estimated glomerular filtration rate (eGFR) in clinical practise. From an international, prospective multicohort study, patients treated with DAAs for at least 12 weeks and with eGFR ≥30 mL/min per 1.73 m 2 at baseline were selected. eGFR was determined using the CKD-EPI formula. A total of 1131 patients were included; 658 (58%) were HIV/HCV-coinfected patients. Among the 901 patients treated for 12 weeks, median (interquartile range) eGFR was 100 (87-107) at baseline vs 97 (85-105) mL/min per 1.73 m 2 at week 12 of follow-up (FU12) post-treatment (P < .001). For HIV-coinfected subjects who received tenofovir plus a ritonavir-boosted HIV protease inhibitor (PI/r), baseline vs FU12 eGFR were 104 (86-109) vs 104 (91-110) mL/min per 1.73 m 2 (P = .913). Among subjects receiving ombitasvir/paritaprevir with or without dasabuvir, eGFR did not show any significant change. Of 1100 subjects with eGFR >60 mL/min per 1.73 m 2 at baseline, 22 (2%) had eGFR <60 mL/min per 1.73 m 2 at FU12, but none presented with eGFR <30 mL/min per 1.73 m 2 . In conclusion, eGFR slightly declines during therapy with all-oral DAAs and this effect persists up to 12 weeks after stopping treatment in subjects with normal to moderately impaired renal function, regardless of HIV status. Concomitant use of tenofovir plus PI/r does not seem to have an impact on eGFR. © 2018 John Wiley & Sons Ltd.

Antiviral and Antioxidant Activities of Sulfated Galactomannans from Plants of Caatinga Biome.

PubMed

Marques, Márcia Maria Mendes; de Morais, Selene Maia; da Silva, Ana Raquel Araújo; Barroso, Naiara Dutra; Pontes Filho, Tadeu Rocha; Araújo, Fernanda Montenegro de Carvalho; Vieira, Ícaro Gusmão Pinto; Lima, Danielle Malta; Guedes, Maria Izabel Florindo

2015-01-01

Dengue represents a serious social and economic public health problem; then trying to contribute to improve its control, the objective of this research was to develop phytoterapics for dengue treatment using natural resources from Caatinga biome. Galactomannans isolated from Adenanthera pavonina L., Caesalpinia ferrea Mart., and Dimorphandra gardneriana Tull were chemically sulfated in order to evaluate the antioxidant, and antiviral activities and the role in the inhibition of virus DENV-2 in Vero cells. A positive correlation between the degree of sulfation, antioxidant and antiviral activities was observed. The sulfated galactomannans showed binding to the virus surface, indicating that they interact with DENV-2. The sulfated galactomannans from C. ferrea showed 96% inhibition of replication of DENV-2 followed by D. gardneriana (94%) and A. pavonina (77%) at 25 µg/mL and all sulfated galactomannans also showed antioxidant activity. This work is the first report of the antioxidant and antiviral effects of sulfated galactomannans against DENV-2. The results are very promising and suggest that these sulfated galactomannans from plants of Caatinga biome act in the early step of viral infection. Thus, sulfated galactomannans may act as an entry inhibitor of DENV-2.

Antiviral and Antioxidant Activities of Sulfated Galactomannans from Plants of Caatinga Biome

PubMed Central

Marques, Márcia Maria Mendes; de Morais, Selene Maia; da Silva, Ana Raquel Araújo; Barroso, Naiara Dutra; Pontes Filho, Tadeu Rocha; Araújo, Fernanda Montenegro de Carvalho; Vieira, Ícaro Gusmão Pinto; Lima, Danielle Malta; Guedes, Maria Izabel Florindo

2015-01-01

Dengue represents a serious social and economic public health problem; then trying to contribute to improve its control, the objective of this research was to develop phytoterapics for dengue treatment using natural resources from Caatinga biome. Galactomannans isolated from Adenanthera pavonina L., Caesalpinia ferrea Mart., and Dimorphandra gardneriana Tull were chemically sulfated in order to evaluate the antioxidant, and antiviral activities and the role in the inhibition of virus DENV-2 in Vero cells. A positive correlation between the degree of sulfation, antioxidant and antiviral activities was observed. The sulfated galactomannans showed binding to the virus surface, indicating that they interact with DENV-2. The sulfated galactomannans from C. ferrea showed 96% inhibition of replication of DENV-2 followed by D. gardneriana (94%) and A. pavonina (77%) at 25 µg/mL and all sulfated galactomannans also showed antioxidant activity. This work is the first report of the antioxidant and antiviral effects of sulfated galactomannans against DENV-2. The results are very promising and suggest that these sulfated galactomannans from plants of Caatinga biome act in the early step of viral infection. Thus, sulfated galactomannans may act as an entry inhibitor of DENV-2. PMID:26257815

Significance of day-1 viral response of hepatitis C virus in patients with chronic hepatitis C receiving direct-acting antiviral therapy.

PubMed

Toyoda, Hidenori; Kumada, Takashi; Tada, Toshifumi; Yama, Tsuyoki; Mizuno, Kazuyuki

2018-06-01

On-treatment response of serum hepatitis C virus (HCV) is reportedly less useful to predict the outcome of anti-HCV therapy with interferon (IFN)-free regimen with direct-acting antivirals than with IFN-based regimens in clinical trials. We evaluated the significance of very early viral response after the start of therapy, which indicates direct HCV response to the drugs, on therapeutic outcome. Reductions in serum HCV-RNA levels were measured at 1 day after the start of therapy in 544 patients who underwent IFN-free direct-acting antiviral regimens. The association between these reductions and the achievement or failure of sustained virologic response (SVR) was evaluated. Patient characteristics did not influence 1-day reduction in serum HCV-RNA except for liver fibrosis. There was no difference in 1-day HCV reduction between SVR and non-SVR patients treated with a 24-week regimen. In contrast, in patients treated with a 12-week regimen, 1-day reduction was significantly greater in SVR than in non-SVR patients (P = 0.0013) and was predictive of SVR versus non-SVR (area under the receiver-operating characteristics curve: 0.80). Whereas the reduction in serum HCV-RNA levels at 1 day after the start of therapy was not associated with treatment outcomes in patients who underwent a 24-week regimen of IFN-free therapy, there was an association in patients receiving a 12-week regimen, and this reduction was predictive of SVR, thus potentially serving as a factor to identify patients at risk of treatment failure. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Directional antenna array (DAA) for communications, control, and data link protection

NASA Astrophysics Data System (ADS)

Molchanov, Pavlo A.; Contarino, Vincent M.

2013-06-01

A next generation of Smart antennas with point-to-point communication and jam, spoof protection capability by verification of spatial position is offered. A directional antenna array (DAA) with narrow irradiation beam provides counter terrorism protection for communications, data link, control and GPS. Communications are "invisible" to guided missiles because of 20 dB smaller irradiation outside the beam and spatial separation. This solution can be implemented with current technology. Directional antennas have higher gain and can be multi-frequency or have wide frequency band in contrast to phase antenna arrays. This multi-directional antenna array provides a multi-functional communication network and simultaneously can be used for command control, data link and GPS.

Laboratory evaluation of the Design Analysis Associates DAA H-3613i radar water-level sensor—Results of temperature, distance, and SDI-12 tests

USGS Publications Warehouse

Carnley, Mark V.

2016-09-30

The Design Analysis Associates (DAA) DAA H-3613i radar water-level sensor (DAA H-3613i), manufactured by Xylem Incorporated, was evaluated by the U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility (HIF) for conformance to manufacturer’s accuracy specifications for measuring a distance throughout the sensor’s operating temperature range, for measuring distances from 3 to 15 feet at ambient temperatures, and for compliance with the SDI-12 serial-to-digital interface at 1200-baud communication standard. The DAA H-3613i is a noncontact water-level sensor that uses pulsed radar to measure the distance between the radar and the water surface from 0.75 to 131 feet over a temperature range of −40 to 60 degrees Celsius (°C). Manufacturer accuracy specifications that were evaluated, the test procedures that followed, and the results obtained are described in this report. The sensor’s accuracy specification of ± 0.01 feet (± 3 millimeters) meets USGS requirements for a primary water-stage sensor used in the operation of a streamgage. The sensor met the manufacturer’s stated accuracy specifications for water-level measurements during temperature testing at a distance of 8 feet from the target over its temperature-compensated operating range of −40 to 60 °C, except at 60 °C. At 60 °C, about half the measurements exceeded the manufacturer’s accuracy specification by not more than 0.005 feet.The sensor met the manufacturer’s stated accuracy specifications for water-level measurements during distance-accuracy testing at the tested distances from 3 to 15 feet above the water surface at the HIF.

Effect of Cigarette Smoking on a Marker for Neuroinflammation: A [11C]DAA1106 Positron Emission Tomography Study.

PubMed

Brody, Arthur L; Hubert, Robert; Enoki, Ryutaro; Garcia, Lizette Y; Mamoun, Michael S; Okita, Kyoji; London, Edythe D; Nurmi, Erika L; Seaman, Lauren C; Mandelkern, Mark A

2017-07-01

In the brain, microglia continuously scan the surrounding extracellular space in order to respond to damage or infection by becoming activated and participating in neuroinflammation. When activated, microglia increase the expression of translocator protein (TSPO) 18 kDa, thereby making the TSPO expression a marker for neuroinflammation. We used the radiotracer [ 11 C]DAA1106 (a ligand for TSPO) and positron emission tomography (PET) to determine the effect of smoking on availability of this marker for neuroinflammation. Forty-five participants (30 smokers and 15 non-smokers) completed the study and had usable data. Participants underwent a dynamic PET scanning session with bolus injection of [ 11 C]DAA1106 (with smokers in the satiated state) and blood draws during PET scanning to determine TSPO affinity genotype and plasma nicotine levels. Whole-brain standardized uptake values (SUVs) were determined, and analysis of variance was performed, with group (smoker vs non-smoker) and genotype as factors, thereby controlling for genotype. Smokers and non-smokers differed in whole-brain SUVs (P=0.006) owing to smokers having 16.8% lower values than non-smokers. The groups did not differ in injected radiotracer dose or body weight, which were used to calculate SUV. An inverse association was found between whole-brain SUV and reported cigarettes per day (P<0.05), but no significant relationship was found for plasma nicotine. Thus, smokers have less [ 11 C]DAA1106 binding globally than non-smokers, indicating less microglial activation. Study findings are consistent with much prior research demonstrating that smokers have impaired inflammatory functioning compared with non-smokers and that constituents of tobacco smoke other than nicotine affect inflammatory processes.

Naturally occurring dominant drug resistance mutations occur infrequently in the setting of recently acquired hepatitis C.

PubMed

Applegate, Tanya L; Gaudieri, Silvana; Plauzolles, Anne; Chopra, Abha; Grebely, Jason; Lucas, Michaela; Hellard, Margaret; Luciani, Fabio; Dore, Gregory J; Matthews, Gail V

2015-01-01

Direct-acting antivirals (DAAs) are predicted to transform hepatitis C therapy, yet little is known about the prevalence of naturally occurring resistance mutations in recently acquired HCV. This study aimed to determine the prevalence and frequency of drug resistance mutations in the viral quasispecies among HIV-positive and -negative individuals with recent HCV. The NS3 protease, NS5A and NS5B polymerase genes were amplified from 50 genotype 1a participants of the Australian Trial in Acute Hepatitis C. Amino acid variations at sites known to be associated with possible drug resistance were analysed by ultra-deep pyrosequencing. A total of 12% of individuals harboured dominant resistance mutations, while 36% demonstrated non-dominant resistant variants below that detectable by bulk sequencing (that is, <20%) but above a threshold of 1%. Resistance variants (<1%) were observed at most sites associated with DAA resistance from all classes, with the exception of sofosbuvir. Dominant resistant mutations were uncommonly observed in the setting of recent HCV. However, low-level mutations to all DAA classes were observed by deep sequencing at the majority of sites and in most individuals. The significance of these variants and impact on future treatment options remains to be determined. Clinicaltrials.gov NCT00192569.

Rate and predictors of treatment failure to all-oral HCV regimens outside clinical trials.

PubMed

Arias, Ana; Aguilera, Antonio; Soriano, Vicente; Benítez-Gutiérrez, Laura; Lledó, Gemma; Navarro, Daniel; Treviño, Ana; Otero, Esteban; Peña, José M; Cuervas-Mons, Valentín; de Mendoza, Carmen

2017-01-01

Cure rates above 90% have been reported in most Phase III clinical trials using distinct all-oral direct-acting antivirals (DAAs) in chronic hepatitis C patients. Preliminary results in real-world patients have confirmed this, although efficacy tends to be lower. All consecutive chronic hepatitis C patients treated with all-oral DAA regimens at three hepatitis clinics in Spain were retrospectively examined. Host and viral factors were tested as predictors of treatment failure. A total of 363 chronic hepatitis C patients had completed a course of all-oral DAA therapy outside clinical trials up to the end of 2015. All but 14 (4%) patients achieved sustained virological response. There were 10 failures that occurred after 12 weeks of sofosbuvir-ledipasvir, despite 5 of them being on ribavirin. All failures but one were relapses. The only patient with viral breakthrough selected NS5B L159F and NS5A Y93H. In multivariate analyses, only advanced liver fibrosis (Metavir F3-F4) and HIV coinfection were significantly associated with treatment failure. A trend towards lower response was seen for HCV genotype 4. Treatment failures outside clinical trials are roughly seen in 4% of chronic hepatitis C patients who complete a course of all-oral DAA therapy, resembling what is seen in registration trials. In our series, outcomes were not significantly influenced by ribavirin addition, IL28B polymorphisms, HCV genotype, high baseline HCV RNA or prior interferon failure. However, advanced liver fibrosis and HIV coinfection were significantly associated with treatment failure. Our findings support that there is still room for individualization of current DAA therapy.

TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein

PubMed Central

Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen

2017-01-01

ABSTRACT Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. PMID:28202764

TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein.

PubMed

Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen; Gao, Guangxia

2017-05-01

Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. Copyright © 2017 American Society for Microbiology.

Rapid and large-scale implementation of HCV treatment advances in France, 2007-2015.

PubMed

Brouard, Cécile; Boussac-Zarebska, Marjorie; Silvain, Christine; Durand, Julien; de Lédinghen, Victor; Pillonel, Josiane; Delarocque-Astagneau, Elisabeth

2017-12-20

The last decade was marked by major advances in HCV treatment with the introduction of first wave protease inhibitors (1st-wave PIs, telaprevir or boceprevir) in 2011 and second direct-acting antivirals (2nd-wave DAAs) in 2014, that followed low effective pegylated interferon α / ribavirin bitherapy. We estimated the number of patients initiating HCV treatment in France between 2007 and 2015 according to the type of therapy, described their demographical characteristics, and estimated how many were cured with 2nd-wave DAAs in 2014-2015. Individual data from the national health insurance information system were analysed. HCV treatment initiation was defined as a drug reimbursement in the absence of any reimbursement for the same drug in the previous six weeks. Between 2007 and 2015, 72,277 patients initiated at least one HCV treatment. The annual number of patients initiating treatment decreased from 2007 (~13,300) to 2010 (~10,000). It then increased with the introduction of 1st-wave PIs (~12,500 in 2012), before decreasing again in 2013 (~8400). A marked increase followed upon the approval of 2nd-wave DAAs in 2014 (~11,600). Approximately, 8700 and 14,700 patients initiated 2nd-wave DAAs in 2014 and 2015, respectively, corresponding to an estimated 20,300 cured patients in 2014-2015. Patients initiating HCV treatment were mostly male (~65% throughout the 9-year period). Women were older than men (mean age: 55.0 vs. 48.9). Increasing age was associated with more advanced treatment. Among patients initiating 2nd-wave DAAs, the proportions of those under 40 and over 79 years old increased between 2014 and 2015, whereas the proportion of those previously treated for HCV 2007 onwards declined. Successive advances in HCV treatment have been rapidly and widely implemented in France. With the announcement of universal access to DAAs in mid-2016 and price reductions, access to 2nd-wave DAAs is expected to expand even more.

Entry inhibitors: New advances in HCV treatment

PubMed Central

Qian, Xi-Jing; Zhu, Yong-Zhe; Zhao, Ping; Qi, Zhong-Tian

2016-01-01

Hepatitis C virus (HCV) infection affects approximately 3% of the world's population and causes chronic liver diseases, including liver fibrosis, cirrhosis, and hepatocellular carcinoma. Although current antiviral therapy comprising direct-acting antivirals (DAAs) can achieve a quite satisfying sustained virological response (SVR) rate, it is still limited by viral resistance, long treatment duration, combined adverse reactions, and high costs. Moreover, the currently marketed antivirals fail to prevent graft reinfections in HCV patients who receive liver transplantations, probably due to the cell-to-cell transmission of the virus, which is also one of the main reasons behind treatment failure. HCV entry is a highly orchestrated process involving initial attachment and binding, post-binding interactions with host cell factors, internalization, and fusion between the virion and the host cell membrane. Together, these processes provide multiple novel and promising targets for antiviral therapy. Most entry inhibitors target host cell components with high genetic barriers and eliminate viral infection from the very beginning of the viral life cycle. In future, the addition of entry inhibitors to a combination of treatment regimens might optimize and widen the prevention and treatment of HCV infection. This review summarizes the molecular mechanisms and prospects of the current preclinical and clinical development of antiviral agents targeting HCV entry. PMID:26733381

IS INCREASED HCV CASE-FINDING COMBINED WITH CURRENT OR 8–12 WEEK DAA THERAPY COST-EFFECTIVE IN UK PRISONS? A PREVENTION BENEFIT ANALYSIS

PubMed Central

Martin, Natasha K; Vickerman, Peter; Brew, Iain F; Williamson, Joan; Miners, Alec; Irving, William L; Saksena, Sushma; Hutchinson, Sharon J; Mandal, Sema; O’Moore, Eamonn; Hickman, Matthew

2016-01-01

Background Prisoners have a high prevalence of Hepatitis C virus (HCV), but case-finding may not have been cost-effective because treatment often exceeded average prison stay combined with a lack of continuity-of-care. We assess the cost-effectiveness of increased HCV case-finding and treatment in UK prisons using short-course therapies. Methods A dynamic HCV transmission model assesses the cost-effectiveness of doubling HCV case-finding (achieved through introducing opt-out HCV testing in UK pilot prisons) and increasing treatment in UK prisons, compared to status-quo voluntary risk-based testing (6% prison entrants/year), using currently recommended therapies (8–24 weeks) or IFN-free DAAs (8–12 weeks, 95% SVR, £3300/wk). Costs (GBP£) and health utilities (quality-adjusted life-years, QALYs) were used to calculate mean incremental cost-effectiveness ratios (ICERs). We assume 56% referral and 2.5%/25% of referred people who inject drugs (PWID)/exPWID treated within 2 months of diagnosis in prison. PWID and ex/nonPWID are in prison an average 4/8 months, respectively. Results Doubling prison testing rates with existing treatments produces a mean ICER of £19,850/QALY gained compared to current testing/treatment, and is 45% likely to be cost-effective under a £20,000 willingness-to-pay (WTP) threshold. Switching to 8–12 week IFN-free DAAs in prisons could increase cost-effectiveness (ICER £15,090/QALY gained). Excluding prevention benefit decreases cost-effectiveness. If >10% referred PWID are treated in prison (2.5% base-case), either treatment could be highly cost-effective (ICER<£13,000). HCV case-finding and IFN-free DAAs could be highly cost-effective if DAA cost is 10% lower or 8 weeks duration. Conclusions Increased HCV testing in UK prisons (such as through opt-out testing) is borderline cost-effective compared to status-quo voluntary risk-based testing under a £20,000 WTP with current treatments, but likely to be cost-effective if short

Chemical genetics-based development of small molecules targeting hepatitis C virus.

PubMed

Jin, Guanghai; Lee, Jisu; Lee, Kyeong

2017-09-01

Hepatitis C virus (HCV) infection is a major worldwide problem that has emerged as one of the most significant diseases affecting humans. There are currently no vaccines or efficient therapies without side effects, despite today's advanced medical technology. Currently, the common therapy for most patients (i.e. genotype 1) is combination of HCV-specific direct-acting antivirals (DAAs). Up to 2011, the standard of care (SOC) was a combination of peg-IFNα with ribavirin (RBV). After approval of NS3/4A protease inhibitor, SOC was peg-IFNα and RBV with either the first-generation DAAs boceprevir or telaprevir. In the past several years, various novel small molecules have been discovered and some of them (i.e., HCV polymerase, protease, helicase and entry inhibitors) have undergone clinical trials. Between 2013 and 2016, the second-generation DAA drugs simeprevir, asunaprevir, daclatasvir, dasabuvir, sofosbuvir, and elbasvir were approved, as well as the combinational drugs Harvoni ® , Zepatier ® , Technivie ® , and Epclusa ® . A number of reviews have been recently published describing the structure-activity relationship (SAR) in the development of HCV inhibitors and outlining current therapeutic approaches to hepatitis C infection. Target identification involves studying a drug's mechanism of action (MOA), and a variety of target identification methods have been developed in the past few years. Chemical biology has emerged as a powerful tool for studying biological processes using small molecules. The use of chemical genetic methods is a valuable strategy for studying the molecular mechanisms of the viral lifecycle and screening for anti-viral agents. Two general screening approaches have been employed: forward and reverse chemical genetics. This review reveals information on the small molecules in HCV drug discovery by using chemical genetics for targeting the HCV protein and describes successful examples of targets identified with these methods.

Polymorphisms associated with resistance to protease inhibitors in naïve patients infected with hepatitis C virus genotype 1 in Argentina: Low prevalence of Q80K.

PubMed

Martínez, Alfredo P; Culasso, Andrés C A; Pérez, Paula S; Romano, Vanesa; Campos, Rodolfo H; Ridruejo, Ezequiel; García, Gabriel; Di Lello, Federico A

2017-08-15

Incorporation of direct acting antivirals (DAA) in the treatment of Hepatitis C Virus (HCV) significantly increases sustained virologic response rates. However, despite the greater potency offered by these antivirals, drug resistance plays a key role in patients with failure to DAA. Nevertheless, there is no information about the prevalence of resistance-associated substitutions (RASs) in Argentina. The aim of this study was to analyze HCV variants resistant to protease inhibitors (PI) in naïve patients infected with HCV genotype 1 from Argentina. In this retrospective cross-sectional study, 103 patients infected with HCV-1 were included. Eighteen positions related with RASs were analyzed by Sanger at baseline and phylogenetic analysis was performed to determine the diversification of this samples. The analyzed RASs were present in 38 out of 103 patients (36.9%) infected with HCV-1. Patients infected with subtype HCV-1b had higher prevalence of baseline RASs than patients infected with HCV-1a [51.6% vs. 12.8%, respectively (p<0.001)]. The Q80K polymorphism was not found in HCV-1a samples, even when 51% of them belonged to cluster 1, which is associated with a high frequency of Q80K. Phylogenetic analysis showed that Argentinean samples were intermingled with sequences from other geographic regions. RASs to PI were highly prevalent and subtype dependent in treatment-naïve Argentinean patients. Surprisingly, Q80K polymorphism was not detected in our study population. The phylogenetic analysis showed no relationship between our samples and other samples from Brazil which also present a low prevalence of Q80K. This study supports the need for surveillance of resistance in patients who will be treated with DAA in each particular country since the observed RASs have very different prevalence worldwide. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of phosphatidylethanol (PEth) in whole blood in comparison to ethyl glucuronide in hair (hEtG) in driving aptitude assessment (DAA).

PubMed

Schröck, Alexandra; Pfäffli, Matthias; König, Stefan; Weinmann, Wolfgang

2016-11-01

For driving aptitude assessment (DAA), the analysis of several alcohol biomarkers is essential for the detection of alcohol intake besides psycho-medical exploration. In Switzerland, EtG in hair (hEtG) is often the only direct marker for abstinence monitoring in DAA. Therefore, the suitability of phosphatidylethanol (PEth) was investigated as additional biomarker. PEth 16:0/18:1 and 16:0/18:2 were determined by online-SPE-LC-MS/MS in 136 blood samples of persons undergoing DAA and compared to hEtG, determined in hair segments taken at the same time. With a PEth 16:0/18:1 threshold of 210 ng/mL for excessive alcohol consumption, all (n = 30) but one tested person also had hEtG values ≥30 pg/mg. In 54 cases, results are not in contradiction to an abstinence as neither PEth (<20 ng/mL) nor hEtG (<7 pg/mg) was detected. In eight cases, both markers showed moderate consumption. Altogether, PEth and hEtG were in accordance in 68 % of the samples, although covering different time periods of alcohol consumption. With receiver operating characteristic analysis, PEth was evaluated to differentiate abstinence, moderate, and excessive alcohol consumption in accordance with hEtG limits. A PEth 16:0/18:1 threshold of 150 ng/mL resulted in the best sensitivity (70.6 %) and specificity (98.8 %) for excessive consumption. Values between 20 and 150 ng/mL passed for moderate consumption, values <20 ng/mL passed for abstinence. As PEth mostly has a shorter detection window (2-4 weeks) than hEtG (up to 6 months depending on hair length), changes in drinking behavior can be detected earlier by PEth than by hEtG analysis alone. Therefore, PEth helps to improve the diagnostic information and is a valuable additional alcohol marker for DAA.

TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP)

PubMed Central

Lau, Zerlina; Cheung, Pamela; Schneider, William M.; Bozzacco, Leonia; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M.; Felsenfeld, Dan P.; MacDonald, Margaret R.

2017-01-01

The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP’s antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP’s ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity. PMID:28060952

TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP).

PubMed

Li, Melody M H; Lau, Zerlina; Cheung, Pamela; Aguilar, Eduardo G; Schneider, William M; Bozzacco, Leonia; Molina, Henrik; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M; Felsenfeld, Dan P; MacDonald, Margaret R

2017-01-01

The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP's antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP's ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity.

Incidence of DAA failure and the clinical impact of retreatment in real-life patients treated in the advanced stage of liver disease: Interim evaluations from the PITER network

PubMed Central

Gaeta, Giovanni Battista; Brunetto, Maurizia Rossana; Di Leo, Alfredo; Iannone, Andrea; Santantonio, Teresa Antonia; Giammario, Adele; Raimondo, Giovanni; Filomia, Roberto; Coppola, Carmine; Amoruso, Daniela Caterina; Blanc, Pierluigi; Del Pin, Barbara; Chemello, Liliana; Cavalletto, Luisa; Morisco, Filomena; Donnarumma, Laura; Rumi, Maria Grazia; Gasbarrini, Antonio; Siciliano, Massimo; Massari, Marco; Corsini, Romina; Coco, Barbara; Madonia, Salvatore; Cannizzaro, Marco; Zignego, Anna Linda; Monti, Monica; Russo, Francesco Paolo; Zanetto, Alberto; Persico, Marcello; Masarone, Mario; Villa, Erica; Bernabucci, Veronica; Taliani, Gloria; Biliotti, Elisa; Chessa, Luchino; Pasetto, Maria Cristina; Andreone, Pietro; Margotti, Marzia; Brancaccio, Giuseppina; Ieluzzi, Donatella; Borgia, Guglielmo; Zappulo, Emanuela; Calvaruso, Vincenza; Petta, Salvatore; Falzano, Loredana; Quaranta, Maria Giovanna; Weimer, Liliana Elena; Rosato, Stefano; Vella, Stefano; Giannini, Edoardo Giovanni

2017-01-01

Background Few data are available on the virological and clinical outcomes of advanced liver disease patients retreated after first-line DAA failure. Aim To evaluate DAA failure incidence and the retreatment clinical impact in patients treated in the advanced liver disease stage. Methods Data on HCV genotype, liver disease severity, and first and second line DAA regimens were prospectively collected in consecutive patients who reached the 12-week post-treatment and retreatment evaluations from January 2015 to December 2016 in 23 of the PITER network centers. Results Among 3,830 patients with advanced fibrosis (F3) or cirrhosis, 139 (3.6%) failed to achieve SVR. Genotype 3, bilirubin levels >1.5mg/dl, platelet count <120,000/mm3 and the sofosbuvir+ribavirin regimen were independent predictors of failure by logistic regression analysis. The failure rate was 7.6% for patients treated with regimens that are no longer recommended or considered suboptimal (sofosbuvir+ribavirin or simeprevir+sofosbuvir±ribavirin), whereas 1.4% for regimens containing sofosbuvir combined with daclatasvir or ledipasvir or other DAAs. Of the patients who failed to achieve SVR, 72 (51.8%) were retreated with a second DAA regimen, specifically 38 (52.7%) with sofosbuvir+daclatasvir, 27 (37.5%) with sofosbuvir+ledipasvir, and 7 (9.7%) with other DAAs ±ribavirin. Among these, 69 (96%) patients achieved SVR12 and 3 (4%) failed. During a median time of 6 months (range: 5–14 months) between failure and the second DAA therapy, the Child-Pugh class worsened in 12 (16.7%) patients: from A to B in 10 patients (19.6%) and from B to C in 2 patients (10.5%), whereas it did not change in the remaining 60 patients. Following the retreatment SVR12 (median time of 6 months; range: 3–12 months), the Child-Pugh class improved in 17 (23.6%) patients: from B to A in 14 (19.4%) patients, from C to A in 1 patient (1.4%) and from C to B in 2 (2.9%) patients; it remained unchanged in 53 patients (73.6%) and

Incidence of DAA failure and the clinical impact of retreatment in real-life patients treated in the advanced stage of liver disease: Interim evaluations from the PITER network.

PubMed

Kondili, Loreta A; Gaeta, Giovanni Battista; Brunetto, Maurizia Rossana; Di Leo, Alfredo; Iannone, Andrea; Santantonio, Teresa Antonia; Giammario, Adele; Raimondo, Giovanni; Filomia, Roberto; Coppola, Carmine; Amoruso, Daniela Caterina; Blanc, Pierluigi; Del Pin, Barbara; Chemello, Liliana; Cavalletto, Luisa; Morisco, Filomena; Donnarumma, Laura; Rumi, Maria Grazia; Gasbarrini, Antonio; Siciliano, Massimo; Massari, Marco; Corsini, Romina; Coco, Barbara; Madonia, Salvatore; Cannizzaro, Marco; Zignego, Anna Linda; Monti, Monica; Russo, Francesco Paolo; Zanetto, Alberto; Persico, Marcello; Masarone, Mario; Villa, Erica; Bernabucci, Veronica; Taliani, Gloria; Biliotti, Elisa; Chessa, Luchino; Pasetto, Maria Cristina; Andreone, Pietro; Margotti, Marzia; Brancaccio, Giuseppina; Ieluzzi, Donatella; Borgia, Guglielmo; Zappulo, Emanuela; Calvaruso, Vincenza; Petta, Salvatore; Falzano, Loredana; Quaranta, Maria Giovanna; Weimer, Liliana Elena; Rosato, Stefano; Vella, Stefano; Giannini, Edoardo Giovanni

2017-01-01

Few data are available on the virological and clinical outcomes of advanced liver disease patients retreated after first-line DAA failure. To evaluate DAA failure incidence and the retreatment clinical impact in patients treated in the advanced liver disease stage. Data on HCV genotype, liver disease severity, and first and second line DAA regimens were prospectively collected in consecutive patients who reached the 12-week post-treatment and retreatment evaluations from January 2015 to December 2016 in 23 of the PITER network centers. Among 3,830 patients with advanced fibrosis (F3) or cirrhosis, 139 (3.6%) failed to achieve SVR. Genotype 3, bilirubin levels >1.5mg/dl, platelet count <120,000/mm3 and the sofosbuvir+ribavirin regimen were independent predictors of failure by logistic regression analysis. The failure rate was 7.6% for patients treated with regimens that are no longer recommended or considered suboptimal (sofosbuvir+ribavirin or simeprevir+sofosbuvir±ribavirin), whereas 1.4% for regimens containing sofosbuvir combined with daclatasvir or ledipasvir or other DAAs. Of the patients who failed to achieve SVR, 72 (51.8%) were retreated with a second DAA regimen, specifically 38 (52.7%) with sofosbuvir+daclatasvir, 27 (37.5%) with sofosbuvir+ledipasvir, and 7 (9.7%) with other DAAs ±ribavirin. Among these, 69 (96%) patients achieved SVR12 and 3 (4%) failed. During a median time of 6 months (range: 5-14 months) between failure and the second DAA therapy, the Child-Pugh class worsened in 12 (16.7%) patients: from A to B in 10 patients (19.6%) and from B to C in 2 patients (10.5%), whereas it did not change in the remaining 60 patients. Following the retreatment SVR12 (median time of 6 months; range: 3-12 months), the Child-Pugh class improved in 17 (23.6%) patients: from B to A in 14 (19.4%) patients, from C to A in 1 patient (1.4%) and from C to B in 2 (2.9%) patients; it remained unchanged in 53 patients (73.6%) and worsened in 2 (2.8%) patients. Of

Interferon-free therapy in hepatitis C virus (HCV) monoinfected and HCV/HIV coinfected patients: effect on cognitive function, fatigue, and mental health.

PubMed

Kleefeld, Felix; Heller, Sophie; Ingiliz, Patrick; Jessen, Heiko; Petersen, Anders; Kopp, Ute; Kraft, Antje; Hahn, Katrin

2018-05-21

The efficacy and safety of interferon-free therapies for hepatitis C virus (HCV) infection have been reported. Considering the accumulating evidence for a direct central nervous system infection by HCV, we aim to evaluate the effect of direct acting antivirals (DAA) therapy on cognitive function in HCV patients. We conducted a longitudinal analysis of the cognitive performance of 22 patients (8 HCV+, 14 HCV+/HIV+) who completed neuropsychological testing at baseline and at week 12 after DAA therapy. In 20 patients, we analyzed specific attention parameters derived from an experimental testing based on the Theory of Visual Attention (TVA). Depression, fatigue, and mental health were assessed as patient reported outcomes. At baseline, 54.5% of the patients met the criteria for cognitive impairment and 40% showed impairment in TVA parameters. Follow-up analysis revealed significant improvements in the domains of visual memory/learning, executive functions, verbal fluency, processing speed, and motor skills but not in verbal learning and attention/working memory. We did not observe significant improvement in visual attention measured by TVA. Fatigue and mental health significantly improved at follow-up. Our findings indicate that successful DAA treatment leads to cognitive improvements in several domains measured by standard neuropsychological testing. The absence of improvement in TVA parameters and of significant improvement in the domain of attention/working memory might reflect the persistence of specific cognitive deficits after HCV eradication. In summary, DAA treatment seems to have a positive effect on some cognitive domains and leads to an improvement in mental health and fatigue in HCV-infected patients.

Linkage and retention in HCV care for HIV-infected populations: early data from the DAA era.

PubMed

Sacks-Davis, Rachel; Doyle, Joseph S; Rauch, Andri; Beguelin, Charles; Pedrana, Alisa E; Matthews, Gail V; Prins, Maria; van der Valk, Marc; Klein, Marina B; Saeed, Sahar; Lacombe, Karine; Chkhartishvili, Nikoloz; Altice, Frederick L; Hellard, Margaret E

2018-04-01

There is currently no published data on the effectiveness of DAA treatment for elimination of HCV infection in HIV-infected populations at a population level. However, a number of relevant studies and initiatives are emerging. This research aims to report cascade of care data for emerging HCV elimination initiatives and studies that are currently being evaluated in HIV/HCV co-infected populations in the context of implementation science theory. HCV elimination initiatives and studies in HIV co-infected populations that are currently underway were identified. Context, intervention characteristics and cascade of care data were synthesized in the context of implementation science frameworks. Seven HCV elimination initiatives and studies were identified in HIV co-infected populations, mainly operating in high-income countries. Four were focused mainly on HCV elimination in HIV-infected gay and bisexual men (GBM), and three included a combination of people who inject drugs (PWID), GBM and other HIV-infected populations. None were evaluating treatment delivery in incarcerated populations. Overall, HCV RNA was detected in 4894 HIV-infected participants (range within studies: 297 to 994): 48% of these initiated HCV treatment (range: 21% to 85%; within studies from a period where DAAs were broadly available the total is 57%, range: 36% to 74%). Among studies with treatment completion data, 96% of 1109 initiating treatment completed treatment (range: 94% to 99%). Among those who could be assessed for sustained virological response at 12 weeks (SVR12), 1631 of 1757 attained SVR12 (93%, range: 86% to 98%). Early results from emerging research on HCV elimination in HIV-infected populations suggest that HCV treatment uptake is higher than reported levels prior to DAA treatment availability, but approximately half of patients remain untreated. These results are among diagnosed populations and additional effort is required to increase diagnosis rates. Among those who have

The Changing Face of Hepatitis C: Recent Advances on HCV Inhibitors Targeting NS5A

PubMed

Rai, Diwakar; Wang, Liu; Jiang, Xuemei; Zhan, Peng; Jia, Haiyong; De Clercq, Erik; Liu, Xinyong

2015-05-05

Current treatment for HCV infections consists of approved direct acting antivirals (DAAs), viz. the protease inhibitors (boceprevir, telaprevir, and simeprevir), NS5B polymerase inhibitors (sofosbuvir) and NS5A inhibitor (ledipasvir) in combination with pegylated interferon α and ribavirin). These treatments have made a great improvement in the treatment of chronic HCV infections in recent years, but their adverse side effects, emergence of resistant mutants, high cost, and increased pill burden have limited their clinical use. Recently, with the increasing knowledge in understanding the HCV life cycle, more targets have been recognized. NS5A protein plays a critical role in assembly of infectious HCV particles and offering potential for HCV therapies. Therefore, discovery and development of novel DAAs targeting NS5A with novel mechanisms of action, is of great necessity to improve the quality of existing HCV treatments. In the present review, we discuss recent advances with NS5A inhibitors with potent anti-HCV activity, and the potential for the development of HCV NS5A inhibitors to combat HCV infections.

IFNL4 ss469415590 Variant Is Associated with Treatment Response in Japanese HCV Genotype 1 Infected Individuals Treated with IFN-Including Regimens

PubMed Central

Miyamura, Tatsuo; Kanda, Tatsuo; Nakamoto, Shingo; Arai, Makoto; Nakamura, Masato; Wu, Shuang; Jiang, Xia; Sasaki, Reina; Yasui, Shin; Ooka, Yoshihiko; Imazeki, Fumio; Mikami, Shigeru; Yokosuka, Osamu

2014-01-01

Aim. Eradication of hepatitis C virus (HCV) is still challenging even if interferon- (IFN-) free regimens with direct-acting antiviral agents (DAAs) for HCV-infected individuals are available in clinical practice. IFNL4 is a newly described protein, associated with human antiviral defenses. We investigated whether IFNL4 ss469415590 variant has an effect on the prediction of treatment response in HCV-infected patients treated with IFN-including regimens. Patients and Methods. In all, 185 patients infected with HCV genotype 1 treated with peg-IFN plus ribavirin, with or without telaprevir, were genotyped for IFNL4 ss469415590. We retrospectively investigated whether the role of IFNL4 ss469415590 variant and other factors could predict sustained virological response (SVR) in Japanese patients infected with HCV genotype 1. Results. There were 65.7%, 31.5%, and 2.8% patients in the IFNL4 ss469415590 TT/TT, TT/-G, and -G/-G groups, respectively. SVR rates were 82.1% or 49.3% in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. IFNL4 ss469415590 variant and HCV viral loads or IFNL4 ss469415590 variant and early virological response were better predictors of SVR in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. Conclusion. In the era of DAAs, measurement of IFNL4 ss469415590 variant could help the prediction of SVR in Japanese HCV genotype 1 infected individuals treated with IFN-including regimens. PMID:25548683

Improvement of ALT decay kinetics by all-oral HCV treatment: Role of NS5A inhibitors and differences with IFN-based regimens

PubMed Central

Cento, Valeria; Nguyen, Thi Huyen Tram; Di Carlo, Domenico; Biliotti, Elisa; Gianserra, Laura; Lenci, Ilaria; Di Paolo, Daniele; Calvaruso, Vincenza; Teti, Elisabetta; Cerrone, Maddalena; Romagnoli, Dante; Melis, Michela; Danieli, Elena; Menzaghi, Barbara; Polilli, Ennio; Siciliano, Massimo; Nicolini, Laura Ambra; Di Biagio, Antonio; Magni, Carlo Federico; Bolis, Matteo; Antonucci, Francesco Paolo; Di Maio, Velia Chiara; Alfieri, Roberta; Sarmati, Loredana; Casalino, Paolo; Bernardini, Sergio; Micheli, Valeria; Rizzardini, Giuliano; Parruti, Giustino; Quirino, Tiziana; Puoti, Massimo; Babudieri, Sergio; D’Arminio Monforte, Antonella; Andreoni, Massimo; Craxì, Antonio; Angelico, Mario; Pasquazzi, Caterina; Taliani, Gloria; Guedj, Jeremie; Ceccherini-Silberstein, Francesca

2017-01-01

Background Intracellular HCV-RNA reduction is a proposed mechanism of action of direct-acting antivirals (DAAs), alternative to hepatocytes elimination by pegylated-interferon plus ribavirin (PR). We modeled ALT and HCV-RNA kinetics in cirrhotic patients treated with currently-used all-DAA combinations to evaluate their mode of action and cytotoxicity compared with telaprevir (TVR)+PR. Study design Mathematical modeling of ALT and HCV-RNA kinetics was performed in 111 HCV-1 cirrhotic patients, 81 treated with all-DAA regimens and 30 with TVR+PR. Kinetic-models and Cox-analysis were used to assess determinants of ALT-decay and normalization. Results HCV-RNA kinetics was biphasic, reflecting a mean effectiveness in blocking viral production >99.8%. The first-phase of viral-decline was faster in patients receiving NS5A-inhibitors compared to TVR+PR or sofosbuvir+simeprevir (p<0.001), reflecting higher efficacy in blocking assembly/secretion. The second-phase, noted δ and attributed to infected-cell loss, was faster in patients receiving TVR+PR or sofosbuvir+simeprevir compared to NS5A-inhibitors (0.27 vs 0.21 d-1, respectively, p = 0.0012). In contrast the rate of ALT-normalization, noted λ, was slower in patients receiving TVR+PR or sofosbuvir+simeprevir compared to NS5A-inhibitors (0.17 vs 0.27 d-1, respectively, p<0.001). There was no significant association between the second-phase of viral-decline and ALT normalization rate and, for a given level of viral reduction, ALT-normalization was more profound in patients receiving DAA, and NS5A in particular, than TVR+PR. Conclusions Our data support a process of HCV-clearance by all-DAA regimens potentiated by NS5A-inhibitor, and less relying upon hepatocyte death than IFN-containing regimens. This may underline a process of “cell-cure” by DAAs, leading to a fast improvement of liver homeostasis. PMID:28545127

Potential Liver Transplant Recipients with Hepatitis C: Should They Be Treated Before or After Transplantation?

PubMed

Anand, Anil C

2017-03-01

Treatment of hepatitis C virus (HCV) with newer directly acting antivirals (DAAs) and lead to sustained viral response (SVR) in majority of patients and SVR has been documented to be associated with reversal of liver cirrhosis. The improved SVR rates and safety profiles of DAAs have led to the treatment of patients with decompensated cirrhosis awaiting liver transplantation (LT). Several clinical trials of DAAs in decompensated HCV patients have recently demonstrated SVR rates above 80%, which have been associated with significant improvements, in the Child-Pugh-Turcotte scores/or model for end-stage liver disease scores in a proportion of patients. Moreover, it has been shown that HCV RNA becomes negative after 2-4 weeks of treatment, and those who are transplanted after becoming HCV RNA negative will be have very low the risk of HCV recurrence after transplantation. Some of the patients may have reached the "point of no return" and may proceed to worsening of decomposition over time. To avoid the risk of worsening, there is an additional option of treating these patients after LT should they develop recurrent HCV infection. Currently there are no guidelines as to select patients who would benefit from treatment prior to LT as opposed to those who will be better off being treated after the transplant surgery. The article discusses a possible approach for such selection.

Safety analysis of sofosbuvir and ledipasvir for treating hepatitis C.

PubMed

Fazel, Yousef; Lam, Brian; Golabi, Pegah; Younossi, Zobair

2015-08-01

The approval of sofosbuvir (SOF), a nucleotide analogue NS5B polymerase inhibitor, and ledipasvir (LDV), a NS5A inhibitor, marked a new chapter in IFN and ribavirin-free treatment of hepatitis C virus (HCV). This drug reduces adverse events associated with IFN therapy. The purpose of this paper is to evaluate the safety and efficacy of LDV/SOF. Clinical trials illustrating safety and efficacy of LDV/SOF are reviewed and compared to other IFN and ribavirin-free treatment options available. In trials enrolling more than 3000 patients, LDV/SOF is well tolerated with a good safety and side-effect profile in diverse cohorts, including previous direct-acting antiviral (DAA) treatment failures, liver transplant recipients, decompensated cirrhosis and HIV/HCV co-infection. As with all DAAs, the potential for drug-drug interactions must be carefully evaluated, as demonstrated by recent post-marketing reports of symptomatic bradycardia when LDV/SOF is co-administered with amiodarone. Currently, dose recommendations cannot be given for patients with advanced renal disease. Trials in this population are ongoing, more study is warranted. When surveying the DAA regimens available, efficacy, safety and tolerability of LDV/SOF is comparable or better, and LDV/SOF provides an option with convenient single-tablet, once daily, ribavirin-free dosing with relatively few significant drug-drug interactions.

Dasabuvir (ABT333) for the treatment of chronic HCV genotype I: a new face of cure, an expert review.

PubMed

Mantry, Parvez S; Pathak, Lakshmikant

2016-01-01

Hepatitis C virus (HCV) affects nearly 1.3% of US population and around 2% of people worldwide. It is associated with serious complication of Cirrhosis and Hepatocellular carcinoma leading to significant morbidity and mortality. Until now the only treatment option for this serious disease was interferon based therapy which had poor tolerance and at best SVR (Sustained virological response) in only 50% of cases. With the introduction of other direct - acting antiviral agents the treatment of HCV has been revolutionized with significantly high rates of cure. Among novel Direct acting antivirals are non-nucleoside inhibitor NS5B which is highly effective in treatment of HCV genotype 1 a and 1b including those with compensated cirrhosis achieving high cure rates with SVR more than 97 % in pooled analysis from six different phase 3 trials. This review will discuss the DAA - Dasabuvir, a non - nucleoside NS5B inhibitor, its mechanism of action, efficacy, safety & tolerance, and drug resistance. Dasabuvir is approved by FDA in combination with other DAA agents called as the 3D(Viekira Pak) in various interferon free regimens achieving high cure rates (SVR >95%) with low adverse effects. In Europe, it is approved by European medicines agency for use in combination with Ombitasvir, Paritaprevir, and ritonavir with or without ribavirin. The drug is used in treatment naive as well as previously treated patient with high success rates. It is also approved in patients with compensated cirrhosis, patients with HIV co-infection and liver transplant recipients which were in the past were excluded from treatment with interferon based therapy. Dasabuvir is extensively evaluated in large clinical trials and shown excellent SVR among HCV genotype1 patient population in combination with other oral DAAs, with good safety profile and tolerance. Its drawback is its genotype restriction, need for ribavirin (RBV) for 1a genotype, low resistance barrier and high cost. It is well tolerated

UAS Integration in the NAS Project: DAA-TCAS Interoperability "mini" HITL Primary Results

NASA Technical Reports Server (NTRS)

Rorie, Conrad; Fern, Lisa; Shively, Jay; Santiago, Confesor

2016-01-01

At the May 2015 SC-228 meeting, requirements for TCAS II interoperability became elevated in priority. A TCAS interoperability workgroup was formed to identify and address key issues/questions. The TCAS workgroup came up with an initial list of questions and a plan to address those questions. As part of that plan, NASA proposed to run a mini HITL to address display, alerting and guidance issues. A TCAS Interoperability Workshop was held to determine potential display/alerting/guidance issues that could be explored in future NASA mini HITLS. Consensus on main functionality of DAA guidance when TCAS II RA occurs. Prioritized list of independent variables for experimental design. Set of use cases to stress TCAS Interoperability.

Inhibitors of the Hepatitis C Virus Polymerase; Mode of Action and Resistance.

PubMed

Eltahla, Auda A; Luciani, Fabio; White, Peter A; Lloyd, Andrew R; Bull, Rowena A

2015-09-29

The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development, and direct-acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens.

Predictors of functional benefit of hepatitis C therapy in a ‘real-life’ cohort

PubMed Central

Steinebrunner, Niels; Stein, Kerstin; Sandig, Catharina; Bruckner, Thomas; Stremmel, Wolfgang; Pathil, Anita

2018-01-01

AIM To define predictors of functional benefit of direct-acting antivirals (DAAs) in patients with chronic hepatitis C virus (HCV) infection and liver cirrhosis. METHODS We analysed a cohort of 199 patients with chronic HCV genotype 1, 2, 3 and 4 infection involving previously treated and untreated patients with compensated (76%) and decompensated (24%) liver cirrhosis at two tertiary centres in Germany. Patients were included with treatment initiation between February 2014 and August 2016. All patients received a combination regimen of one or more DAAs for either 12 or 24 wk. Predictors of functional benefit were assessed in a univariable as well as multivariable model by binary logistic regression analysis. RESULTS Viral clearance was achieved in 88% (175/199) of patients. Sustained virological response (SVR) 12 rates were as follows: among 156 patients with genotype 1 infection the SVR 12 rate was 90% (n = 141); among 7 patients with genotype 2 infection the SVR 12 rate was 57% (n = 4); among 30 patients with genotype 3 infection the SVR 12 rate was 87% (n = 26); and among 6 patients with genotype 4 infection the SVR 12 rate was 67% (n = 4). Follow-up MELD scores were available for 179 patients. A MELD score improvement was observed in 37% (65/179) of patients, no change of MELD score in 41% (74/179) of patients, and an aggravation was observed in 22% (40/179) of patients. We analysed predictors of functional benefit from antiviral therapy in our patients beyond viral eradication. We identified the Child-Pugh score, the MELD score, the number of platelets and the levels of albumin and bilirubin as significant factors for functional benefit. CONCLUSION Our data may contribute to the discussion of potential risks and benefits of antiviral therapy with individual patients infected with HCV and with advanced liver disease. PMID:29467555

Broad-spectrum antivirals against viral fusion

PubMed Central

Vigant, Frederic; Santos, Nuno C.; Lee, Benhur

2015-01-01

Effective antivirals have been developed against specific viruses, such as HIV, Hepatitis C virus and influenza virus. This ‘one bug–one drug’ approach to antiviral drug development can be successful, but it may be inadequate for responding to an increasing diversity of viruses that cause significant diseases in humans. The majority of viral pathogens that cause emerging and re-emerging infectious diseases are membrane-enveloped viruses, which require the fusion of viral and cell membranes for virus entry. Therefore, antivirals that target the membrane fusion process represent new paradigms for broad-spectrum antiviral discovery. In this Review, we discuss the mechanisms responsible for the fusion between virus and cell membranes and explore how broad-spectrum antivirals target this process to prevent virus entry. PMID:26075364

The Generic Resolution Advisor and Conflict Evaluator (GRACE) for Detect-And-Avoid (DAA) Systems

NASA Technical Reports Server (NTRS)

Abramson, Michael; Refai, Mohamad; Santiago, Confesor

2017-01-01

The paper describes the Generic Resolution Advisor and Conflict Evaluator (GRACE), a novel alerting and guidance algorithm that combines flexibility, robustness, and computational efficiency. GRACE is "generic" in that it makes no assumptions regarding temporal or spatial scales, aircraft performance, or its sensor and communication systems. Accordingly, GRACE is well suited to research applications where alerting and guidance is a central feature and requirements are fluid involving a wide range of aviation technologies. GRACE has been used at NASA in a number of real-time and fast-time experiments supporting evolving requirements of DAA research, including parametric studies, NAS-wide simulations, human-in-the-loop experiments, and live flight tests.

Beyond interferon: rationale and prospects for newer treatment paradigms for chronic hepatitis C

PubMed Central

Cortez, Karoll J.

2015-01-01

Hepatitis C virus (HCV) infection results in a chronic carrier state in 80% of individuals infected with the virus and presently affects over 170 million people worldwide. Approximately 20% of those chronically infected will ultimately progress to develop cirrhosis and death due to end-stage liver disease or hepatocellular carcinoma (HCC). Unlike many other chronic viral infections, effective treatments for HCV are available. Cure from the infection is known as a sustained virologic response (SVR). SVR is associated with reversal of the long-term outcomes of chronic liver disease, decrease in incidence of HCC, and decrease HCV attributable mortality. The current FDA approved therapies for hepatitis C virus genotype 1 (GT-1) include pegylated interferon (PEG-IFN) and ribavirin (RBV) in combination with a directly acting antiviral agent (DAA). New therapeutic advances are being made aiming to simplify management, improve the tolerability of treatment, and shorten the duration of therapy. Moreover, treatment regimens that will effectively eradicate hepatitis C without the use of interferon formulations (IFN) are being developed. In this review, we report the transition of HCV therapeutics from an interferon-α based combination therapy to an all-oral, directly acting antiviral therapy. PMID:25553238

Ribonuclease from Bacillus Acts as an Antiviral Agent against Negative- and Positive-Sense Single Stranded Human Respiratory RNA Viruses

PubMed Central

Müller, Christin; Romanova, Yulia; Mostafa, Ahmed; Ulyanova, Vera; Pleschka, Stephan; Ilinskaya, Olga

2017-01-01

Bacillus pumilus ribonuclease (binase) was shown to be a promising antiviral agent in animal models and cell cultures. However, the mode of its antiviral action remains unknown. To assess the binase effect on intracellular viral RNA we have selected single stranded negative- and positive-sense RNA viruses, influenza virus, and rhinovirus, respectively, which annually cause respiratory illnesses and are characterized by high contagious nature, mutation rate, and antigen variability. We have shown that binase exerts an antiviral effect on both viruses at the same concentration, which does not alter the spectrum of A549 cellular proteins and expression of housekeeping genes. The titers of influenza A (H1N1pdm) virus and human rhinovirus serotype 1A were reduced by 40% and 65%, respectively. A preincubation of influenza virus with binase before infection significantly reduced viral titer after single-cycle replication of the virus. Using influenza A virus mini genome system we showed that binase reduced GFP reporter signaling indicating a binase action on the expression of viral mRNA. Binase reduced the level of H1N1pdm viral NP mRNA accumulation in A549 cells by 20%. Since the viral mRNA is a possible target for binase this agent could be potentially applied in the antiviral therapy against both negative- and positive-sense RNA viruses. PMID:28546965

Current antiviral drugs and their analysis in biological materials - Part II: Antivirals against hepatitis and HIV viruses.

PubMed

Nováková, Lucie; Pavlík, Jakub; Chrenková, Lucia; Martinec, Ondřej; Červený, Lukáš

2018-01-05

This review is a Part II of the series aiming to provide comprehensive overview of currently used antiviral drugs and to show modern approaches to their analysis. While in the Part I antivirals against herpes viruses and antivirals against respiratory viruses were addressed, this part concerns antivirals against hepatitis viruses (B and C) and human immunodeficiency virus (HIV). Many novel antivirals against hepatitis C virus (HCV) and HIV have been introduced into the clinical practice over the last decade. The recent broadening portfolio of these groups of antivirals is reflected in increasing number of developed analytical methods required to meet the needs of clinical terrain. Part II summarizes the mechanisms of action of antivirals against hepatitis B virus (HBV), HCV, and HIV, their use in clinical practice, and analytical methods for individual classes. It also provides expert opinion on state of art in the field of bioanalysis of these drugs. Analytical methods reflect novelty of these chemical structures and use by far the most current approaches, such as simple and high-throughput sample preparation and fast separation, often by means of UHPLC-MS/MS. Proper method validation based on requirements of bioanalytical guidelines is an inherent part of the developed methods. Copyright © 2017 Elsevier B.V. All rights reserved.

On-treatment decrease of NKG2D correlates to early emergence of clinically evident hepatocellular carcinoma after interferon-free therapy for chronic hepatitis C.

PubMed

Chu, Po-Sung; Nakamoto, Nobuhiro; Taniki, Nobuhito; Ojiro, Keisuke; Amiya, Takeru; Makita, Yuko; Murata, Hiroko; Yamaguchi, Akihiro; Shiba, Shunsuke; Miyake, Rei; Katayama, Tadashi; Ugamura, Aya; Ikura, Akihiko; Takeda, Karin; Ebinuma, Hirotoshi; Saito, Hidetsugu; Kanai, Takanori

2017-01-01

Interferon (IFN)- free direct antiviral agents (DAAs) with rapid HCV eradication might evoke immunological reconstitutions, and some early recurrences of HCC after IFN-free DAAs have been reported. This study aimed to investigate whether natural killer group 2, member D (NKG2D) predicts early emergence of HCC after IFN-free DAAs. We conducted a clinical practice-based observational study of 101 patients infected with genotype 1 HCV who received IFN-free (DAAs), and stratified them into those who did or did not develop early (i.e., during the 6-month surveillance period following treatment.) recurrence or occurrence of clinically evident HCC. We also analyzed the peripheral blood mononuclear cells, both before treatment and at end of treatment (EOT), of 24 of the patients who received IFN-free DAAs, and 16 who received IFN-combined protease inhibitor. We found early emergence of clinically evident HCC after IFN-free DAAs in 12 (12%) patients. Higher pre-treatment NKG2D expression, higher FIB-4 score, previous HCC history and failure to achieve sustained viral response were significant factors correlating to early HCC emergence. After IFN-free DAAs, a rapid decrease of NKG2D at EOT correlated with early HCC emergence in the IFN-free DAA-treated patients, but not in patients treated with the IFN-combined regimen. The decrease of NKG2D until EOT was predictive of early HCC emergence at a cut-off of -52% (AUC = 0.92). On-treatment decrease of NKG2D may be a useful predictor of early emerging HCC in patients treated with IFN-free DAAs.

The cost impact of outreach testing and treatment for hepatitis C in an urban Drug Treatment Unit.

PubMed

Selvapatt, Nowlan; Ward, Thomas; Harrison, Lorna; Lombardini, Jody; Thursz, Mark; McEwan, Phil; Brown, Ashley

2017-03-01

In developed countries persons who inject drugs (PWID) represents a significant risk for chronic hepatitis C virus (HCV). It is reported that up to half of persons with chronic HCV remain undiagnosed and reliance on attendance to specialist clinics remain a barrier to treatment. This study assesses the feasibility and cost-effectiveness of outreach screening and treatment within a Drug Treatment Unit (DTU). All persons attending a London DTU were offered HCV testing, and where appropriate follow-up and treatment by a specialist nurse at the DTU. Three years of data informed a cost-effective-analysis using a validated Markov model. A hypothetical scenario in which only direct acting antiviral (DAA) treatments were used was also assessed. Of 321 persons eligible, 216 were screened, 89 were HCV positive and 66 had confirmatory evidence of viraemia. All were infected with either HCV genotype 1 or 3. Treatment was initiated in 29 persons, 22 with interferon based and 7 DAA only regimens. Following initial treatment 21 (72%) achieved SVR12. It is estimated that this programme represents an average per-patient cost-saving of £2498 and a quality-adjusted life year (QALY) gain of 4.10 over a lifetime. In a hypothetical scenario of all oral DAA treatment, an incremental cost per QALY of £1029 was estimated. This study demonstrates feasibility and cost effectiveness of outreach testing and treatment of hepatitis C within comparable DTU settings. Additional costs of newer DAA therapies would not be prohibitive when considering willingness-to-pay thresholds commonly used by policy makers. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Daclatasvir inhibits hepatitis C virus NS5A motility and hyper-accumulation of phosphoinositides

PubMed Central

Chukkapalli, Vineela; Berger, Kristi L.; Kelly, Sean M.; Thomas, Meryl; Deiters, Alexander; Randall, Glenn

2014-01-01

Combinations of direct-acting antivirals (DAAs) against the hepatitis C virus (HCV) have the potential to revolutionize the HCV therapeutic regime. An integral component of DAA combination therapies are HCV NS5A inhibitors. It has previously been proposed that NS5A DAAs inhibit two functions of NS5A: RNA replication and virion assembly. In this study, we characterize the impact of a prototype NS5A DAA, daclatasvir (DCV), on HCV replication compartment formation. DCV impaired HCV replicase localization and NS5A motility. In order to characterize the mechanism behind altered HCV replicase localization, we examined the impact of DCV on the interaction of NS5A with its essential cellular cofactor, phosphatidylinositol-4-kinase III α (PI4KA). We observed that DCV does not inhibit PI4KA directly, nor does it impair early events of the NS5A-PI4KA interaction that can occur when NS5A is expressed alone. NS5A functions that are unaffected by DCV include PI4KA binding, as determined by co-immunoprecipitation, and a basal accumulation of the PI4KA product, PI4P. However, DCV impairs late steps in PI4KA activation that requires NS5A expressed in the context of the HCV polyprotein. These NS5A functions include hyper-stimulation of PI4P levels and appropriate replication compartment formation. The data are most consistent with a model wherein DCV inhibits conformational changes in the NS5A protein or protein complex formations that occur in the context of HCV polyprotein expression and stimulate PI4P hyper-accumulation and replication compartment formation. PMID:25546252

Hepatitis B and C coinfection in a real-life setting: viral interactions and treatment issues.

PubMed

Papadopoulos, Nikolaos; Papavdi, Maria; Pavlidou, Anna; Konstantinou, Dimitris; Kranidioti, Hariklia; Kontos, George; Koskinas, John; Papatheodoridis, George V; Manolakopoulos, Spilios; Deutsch, Melanie

2018-01-01

Only limited data concerning hepatitis B (HBV) and C viruses (HCV) coinfection are available. Direct-acting antivirals (DAAs) may be more effective for HCV clearance than interferon (IFN)-based regimens with a risk of HBV reactivation. We retrospectively enrolled 40 HBV/HCV-coinfected patients to evaluate their clinical profile and treatment outcomes. Chronic dual infection was present in 25/40 (62.5%) patients, acute HCV superinfection in 5/40 (12.5%) patients and acute HBV superinfection in 10/40 (25%). Twenty-five patients (62.5%) were treated: 16/25 (64%) with IFN, 4/25 (16%) with nucleot(s)ide analogs (NUCs) and 5/25 (20%) with DAAs. Of the 16 patients treated with IFN-based therapy, 6 (37.5%) achieved both sustained virological response (SVR) and HBsAg clearance. Of the 4 patients treated with NUCs, one (25%) achieved both SVR and HBsAg clearance. All five patients treated with DAAs (100%) achieved SVR, while one case of HBV reactivation was recorded. Fifteen of the 40 patients (37.5%) did not receive any treatment. Eight of them (53.5%) presented with acute HBV superinfection: spontaneous HCV clearance was recorded in 5/8 (62.5%), while HBsAg clearance occurred in 6/8 (75%). Three of them (20%) presented with acute HCV superinfection; spontaneous HCV clearance was recorded in one of the three (33.5%). The other four patients (26.5%) presented with dual HBV/HCV infection. A significant proportion of patients presented with active HBV replication. Treatment with DAAs seems to be efficacious for HCV eradication. However, clinicians should be aware of HBV reactivation. HBV superinfection may lead to both HBsAg and HCV clearance.

Ultrasensitive HCV RNA Quantification in Antiviral Triple Therapy: New Insight on Viral Clearance Dynamics and Treatment Outcome Predictors

PubMed Central

Garbuglia, Anna Rosa; Visco-Comandini, Ubaldo; Lionetti, Raffaella; Lapa, Daniele; Castiglione, Filippo; D’Offizi, Gianpiero; Taibi, Chiara; Montalbano, Marzia; Capobianchi, Maria Rosaria; Paci, Paola

2016-01-01

Objectives Identifying the predictive factors of Sustained Virological Response (SVR) represents an important challenge in new interferon-based DAA therapies. Here, we analyzed the kinetics of antiviral response associated with a triple drug regimen, and the association between negative residual viral load at different time points during treatment. Methods Twenty-three HCV genotype 1 (GT 1a n = 11; GT1b n = 12) infected patients were included in the study. Linear Discriminant Analysis (LDA) was used to establish possible association between HCV RNA values at days 1 and 4 from start of therapy and SVR. Principal component analysis (PCA) was applied to analyze the correlation between HCV RNA slope and SVR. A ultrasensitive (US) method was established to measure the residual HCV viral load in those samples which resulted “detected <12IU/ml” or undetectable with ABBOTT standard assay, and was retrospectively used on samples collected at different time points to establish its predictive power for SVR. Results According to LDA, there was no association between SVR and viral kinetics neither at time points earlier than 1 week (days 1 and 4) after therapy initiation nor later. The slopes were not relevant for classifying patients as SVR or no-SVR. No significant differences were observed in the median HCV RNA values at T0 among SVR and no-SVR patients. HCV RNA values with US protocol (LOD 1.2 IU/ml) after 1 month of therapy were considered; the area under the ROC curve was 0.70. Overall, PPV and NPV of undetectable HCV RNA with the US method for SVR was 100% and 46.7%, respectively; sensitivity and specificity were 38.4% and 100% respectively. Conclusion HCV RNA “not detected” by the US method after 1 month of treatment is predictive of SVR in first generation Protease inhibitor (PI)-based triple therapy. The US method could have clinical utility for advanced monitoring of virological response in new interferon based DAA combination regimens. PMID:27560794

Long-acting antiviral agents for HIV treatment

PubMed Central

Margolis, David A.; Boffito, Marta

2015-01-01

Purpose of review Long-acting antiretroviral (ARV) agents are currently under development for the treatment of chronic HIV infection. This review focuses on data recently produced on injectable ARVs for patients living with HIV/AIDS and on the patients’ perspectives on the use of these agents. Recent findings Crystalline nanoparticle formulations of the nonnucleoside reverse transcriptase inhibitor rilpivirine (TMC278) and of the HIV-1 integrase strand transfer inhibitor cabotegravir (GSK1265744) have progressed into phase II clinical trials as injectable maintenance therapy for patients living with HIV/AIDS with an undetectable viral load. Summary Phase II studies evaluating the coadministration of rilpivirine and cabotegravir intramuscularly to HIV-infected individuals with an undetectable viral load are currently underway. Rilpivirine and cabotegravir are characterized by different mechanisms of action against HIV and a favorable drug interaction profile, providing a rationale for coadministration. The high potency and low daily dosing requirements of oral cabotegravir and rilpivirine facilitate long-acting formulation development. Intramuscular dosing is preceded by an oral lead-in phase to assess safety and tolerability in individual participants. In addition to assessing the safety of injectable therapies in ongoing studies, it will be important to evaluate whether differences in drug adherence between injectable and oral therapies lead to different virologic outcomes, including rates of virologic failure and the emergence of resistance. Long-acting formulations may be associated with challenges, such as the management of adverse effects with persistent drug concentrations and the risk of virologic resistance, as drug concentrations decline following discontinuation. PMID:26049949

Alveolar macrophage–derived type I interferons orchestrate innate immunity to RSV through recruitment of antiviral monocytes

PubMed Central

Goritzka, Michelle; Makris, Spyridon; Kausar, Fahima; Durant, Lydia R.; Pereira, Catherine; Kumagai, Yutaro; Culley, Fiona J.; Mack, Matthias; Akira, Shizuo

2015-01-01

Type I interferons (IFNs) are important for host defense from viral infections, acting to restrict viral production in infected cells and to promote antiviral immune responses. However, the type I IFN system has also been associated with severe lung inflammatory disease in response to respiratory syncytial virus (RSV). Which cells produce type I IFNs upon RSV infection and how this directs immune responses to the virus, and potentially results in pathological inflammation, is unclear. Here, we show that alveolar macrophages (AMs) are the major source of type I IFNs upon RSV infection in mice. AMs detect RSV via mitochondrial antiviral signaling protein (MAVS)–coupled retinoic acid–inducible gene 1 (RIG-I)–like receptors (RLRs), and loss of MAVS greatly compromises innate immune restriction of RSV. This is largely attributable to loss of type I IFN–dependent induction of monocyte chemoattractants and subsequent reduced recruitment of inflammatory monocytes (infMo) to the lungs. Notably, the latter have potent antiviral activity and are essential to control infection and lessen disease severity. Thus, infMo recruitment constitutes an important and hitherto underappreciated, cell-extrinsic mechanism of type I IFN–mediated antiviral activity. Dysregulation of this system of host antiviral defense may underlie the development of RSV-induced severe lung inflammation. PMID:25897172

Discovery of a Broad-Spectrum Antiviral Compound That Inhibits Pyrimidine Biosynthesis and Establishes a Type 1 Interferon-Independent Antiviral State

PubMed Central

Adcock, Robert S.; Schroeder, Chad E.; Chu, Yong-Kyu; Sotsky, Julie B.; Cramer, Daniel E.; Chilton, Paula M.; Song, Chisu; Anantpadma, Manu; Davey, Robert A.; Prodhan, Aminul I.; Yin, Xinmin; Zhang, Xiang

2016-01-01

Viral emergence and reemergence underscore the importance of developing efficacious, broad-spectrum antivirals. Here, we report the discovery of tetrahydrobenzothiazole-based compound 1, a novel, broad-spectrum antiviral lead that was optimized from a hit compound derived from a cytopathic effect (CPE)-based antiviral screen using Venezuelan equine encephalitis virus. Compound 1 showed antiviral activity against a broad range of RNA viruses, including alphaviruses, flaviviruses, influenza virus, and ebolavirus. Mechanism-of-action studies with metabolomics and molecular approaches revealed that the compound inhibits host pyrimidine synthesis and establishes an antiviral state by inducing a variety of interferon-stimulated genes (ISGs). Notably, the induction of the ISGs by compound 1 was independent of the production of type 1 interferons. The antiviral activity of compound 1 was cell type dependent with a robust effect observed in human cell lines and no observed antiviral effect in mouse cell lines. Herein, we disclose tetrahydrobenzothiazole compound 1 as a novel lead for the development of a broad-spectrum, antiviral therapeutic and as a molecular probe to study the mechanism of the induction of ISGs that are independent of type 1 interferons. PMID:27185801

Nucleobases and corresponding nucleosides display potent antiviral activities against dengue virus possibly through viral lethal mutagenesis.

PubMed

Qiu, Li; Patterson, Steven E; Bonnac, Laurent F; Geraghty, Robert J

2018-04-01

Dengue virus affects millions of people worldwide each year. To date, there is no drug for the treatment of dengue-associated disease. Nucleosides are effective antivirals and work by inhibiting the accurate replication of the viral genome. Nucleobases offer a cheaper alternative to nucleosides for broad antiviral applications. Metabolic activation of nucleobases involves condensation with 5-phosphoribosyl-1-pyrophosphate to give the corresponding nucleoside-5'-monophosphate. This could provide an alternative to phosphorylation of a nucleoside, a step that is often rate limiting and inefficient in activation of nucleosides. We evaluated more than 30 nucleobases and corresponding nucleosides for their antiviral activity against dengue virus. Five nucleobases and two nucleosides were found to induce potent antiviral effects not previously described. Our studies further revealed that nucleobases were usually more active with a better tissue culture therapeutic index than their corresponding nucleosides. The development of viral lethal mutagenesis, an antiviral approach that takes into account the quasispecies behavior of RNA viruses, represents an exciting prospect not yet studied in the context of dengue replication. Passage of the virus in the presence of the nucleobase 3a (T-1105) and corresponding nucleoside 3b (T-1106), favipiravir derivatives, induced an increase in apparent mutations, indicating lethal mutagenesis as a possible antiviral mechanism. A more concerted and widespread screening of nucleobase libraries is a very promising approach to identify dengue virus inhibitors including those that may act as viral mutagens.

Mechanisms of Antiviral Action of Plant Antimicrobials against Murine Norovirus

PubMed Central

Gilling, Damian H.; Kitajima, Masaaki; Torrey, Jason R.

2014-01-01

Numerous plant compounds have antibacterial or antiviral properties; however, limited research has been conducted with nonenveloped viruses. The efficacies of allspice oil, lemongrass oil, and citral were evaluated against the nonenveloped murine norovirus (MNV), a human norovirus surrogate. The antiviral mechanisms of action were also examined using an RNase I protection assay, a host cell binding assay, and transmission electron microscopy. All three antimicrobials produced significant reductions (P ≤ 0.05) in viral infectivity within 6 h of exposure (0.90 log10 to 1.88 log10). After 24 h, the reductions were 2.74, 3.00, and 3.41 log10 for lemongrass oil, citral, and allspice oil, respectively. The antiviral effect of allspice oil was both time and concentration dependent; the effects of lemongrass oil and citral were time dependent. Based on the RNase I assay, allspice oil appeared to act directly upon the viral capsid and RNA. The capsids enlarged from ≤35 nm to up to 75 nm following treatment. MNV adsorption to host cells was not significantly affected. Alternatively, the capsid remained intact following exposure to lemongrass oil and citral, which appeared to coat the capsid, causing nonspecific and nonproductive binding to host cells that did not lead to successful infection. Such contrasting effects between allspice oil and both lemongrass oil and citral suggest that though different plant compounds may yield similar reductions in virus infectivity, the mechanisms of inactivation may be highly varied and specific to the antimicrobial. This study demonstrates the antiviral properties of allspice oil, lemongrass oil, and citral against MNV and thus indicates their potential as natural food and surface sanitizers to control noroviruses. PMID:24907316

Primary Hepatic Marginal Zone Lymphoma in a Patient with Chronic Hepatitis C.

PubMed

Gherlan, George S; Stoia, Razvan; Enyedi, Mihaly; Dobrea, Camelia; Calistru, Petre I

2016-09-01

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is a low-grade malignant lymphoma that appears frequently in the stomach, but other sites can also be involved: the intestinal tract, lungs, head, neck, skin, thyroid, breasts and liver. Recently, epidemiological evidences support the idea that there is an association between hepatitis C and B-cell non-Hodgkin lymphomas (that include MALT as a subtype). Primary non-Hodgkin lymphomas confi ned only to the liver are very rare (only 0.016% of all cases of all non-Hodgkin's lymphomas) and MALT is not the most frequent type. We present the case of a male patient, age 62, known with chronic hepatitis C, previously relapser a" er a 72 week treatment with peg-interferon alfa and ribavirin that was diagnosed at three years a" er the relapse with multiple focal liver lesions. One of the tumors was surgically removed and the histological exam performed demonstrated an extranodal marginal zone lymphoma with small B-cell with plasmacytoid diff erentiation confi ned only to the liver. Direct acting antiviral (DAA) therapy was started, but the virologic clearance was not obtained by week 10, leading to a change of DAA regimen at week 12. The antiviral therapy was continued until week 24. Imaging showed an increase in number and size of the focal lesions until week 12. At week 12 chemo- and immune-therapy was started with bendamustine and rituximab. A" erwards the evolution was favorable, the patient being now in complete remission and with undetectable viral load.

Chronic Hepatitis C Treatment with Daclatasvir Plus Asunaprevir Does Not Lead to a Decreased Quality of Life.

PubMed

Kawakubo, Megumi; Eguchi, Yuichiro; Okada, Michiaki; Iwane, Shinji; Oeda, Satoshi; Otsuka, Taiga; Nakashita, Syunya; Araki, Norimasa; Koga, Akemi

2018-03-09

Objective The aim of this study was to determine if direct-acting antiviral (DAA) treatment with daclatasvir (DCV) plus asunaprevir (ASV) for 24 weeks influenced the health-related quality of life (HRQOL) at 12 and 24 weeks after treatment initiation (end of treatment [EOT]). Methods This was a prospective, longitudinal study comparing the HRQOL of patients receiving DAA treatment at 12 weeks after treatment initiation and EOT with the HRQOL at baseline. We used a Japanese-validated version of the 8-item Short Form Health Survey (SF-8) to assess the HRQOL of patients. This score can be compared to the Japanese normative sample scores of SF-8. Wilcoxon signed-rank tests were used to compare the HRQOL before treatment, 12 weeks after treatment initiation, and at EOT. Patients We enrolled patients who received 24-week combination therapy using DCV and ASV for HCV at Saga University Hospital between November 2014 and July 2015. Those who discontinued treatment due to relapse or adverse reactions during the treatment period were excluded from the study. Results There were no significant changes in any of the SF-8 subscales, Physical component scores (PCS) or mental component scores (MCS) during the treatment period for both males and females. Conclusion Our study makes a significant contribution to the literature because 24-week DAA treatment with DCV plus ASV did not decrease the HRQOL at 12 or 24 weeks after treatment initiation.

HCV-RNA quantification in liver bioptic samples and extrahepatic compartments, using the abbott RealTime HCV assay.

PubMed

Antonucci, FrancescoPaolo; Cento, Valeria; Sorbo, Maria Chiara; Manuelli, Matteo Ciancio; Lenci, Ilaria; Sforza, Daniele; Di Carlo, Domenico; Milana, Martina; Manzia, Tommaso Maria; Angelico, Mario; Tisone, Giuseppe; Perno, Carlo Federico; Ceccherini-Silberstein, Francesca

2017-08-01

We evaluated the performance of a rapid method to quantify HCV-RNA in the hepatic and extrahepatic compartments, by using for the first time the Abbott RealTime HCV-assay. Non-tumoral (NT), tumoral (TT) liver samples, lymph nodes and ascitic fluid from patients undergoing orthotopic-liver-transplantation (N=18) or liver resection (N=4) were used for the HCV-RNA quantification; 5/22 patients were tested after or during direct acting antivirals (DAA) treatment. Total RNA and DNA quantification from tissue-biopsies allowed normalization of HCV-RNA concentrations in IU/μg of total RNA and IU/10 6 liver-cells, respectively. HCV-RNA was successfully quantified with high reliability in liver biopsies, lymph nodes and ascitic fluid samples. Among the 17 untreated patients, a positive and significant HCV-RNA correlation between serum and NT liver-samples was observed (Pearson: rho=0.544, p=0.024). Three DAA-treated patients were HCV-RNA "undetectable" in serum, but still "detectable" in all tested liver-tissues. Differently, only one DAA-treated patient, tested after sustained-virological-response, showed HCV-RNA "undetectability" in liver-tissue. HCV-RNA was successfully quantified with high reliability in liver bioptic samples and extrahepatic compartments, even when HCV-RNA was "undetectable" in serum. Abbott RealTime HCV-assay is a good diagnostic tool for HCV quantification in intra- and extra-hepatic compartments, whenever a bioptic sample is available. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of Hepatitis C Virus Decline during Treatment with the Protease Inhibitor Danoprevir Using a Multiscale Model

DOE PAGES

Rong, Libin; Guedj, Jeremie; Dahari, Harel; ...

2013-03-14

The current paradigm for studying hepatitis C virus (HCV) dynamics in patients utilizes a standard viral dynamic model that keeps track of uninfected (target) cells, infected cells, and virus. The model does not account for the dynamics of intracellular viral replication, which is the major target of direct-acting antiviral agents (DAAs). In this paper, we describe and study a recently developed multiscale age-structured model that explicitly considers the potential effects of DAAs on intracellular viral RNA production, degradation, and secretion as virus into the circulation. We show that when therapy significantly blocks both intracellular viral RNA production and virus secretion,more » the serum viral load decline has three phases, with slopes reflecting the rate of serum viral clearance, the rate of loss of intracellular viral RNA, and the rate of loss of intracellular replication templates and infected cells, respectively. We also derive analytical approximations of the multiscale model and use one of them to analyze data from patients treated for 14 days with the HCV protease inhibitor danoprevir. Analysis suggests that danoprevir significantly blocks intracellular viral production (with mean effectiveness 99.2%), enhances intracellular viral RNA degradation about 5-fold, and moderately inhibits viral secretion (with mean effectiveness 56%). Finally, the multiscale model can be used to study viral dynamics in patients treated with other DAAs and explore their mechanisms of action in treatment of hepatitis C.« less

A 2015 roadmap for the management of hepatitis C virus infections in Asia.

PubMed

Lim, Seng Gee; Dan, Yock Young

2015-07-01

The prevalence of hepatitis C virus (HCV) in Asia is 0.5% to 4.7%, with three different genotypes predominating, depending on the geographic region: genotype 1b in East Asia, genotype 3 in South and Southeast Asia, and genotype 6 in Indochina. Official approval for direct-acting antiviral agents (DAAs) in Asia lags significantly behind that in the West, such that in most countries the mainstay of therapy is still pegylated interferon and ribavirin (PR). Because the interleukin-28B genetic variant, associated with a high sustained virologic response (SVR), is common in Asians, this treatment is still acceptable in Asian patients with HCV infections. A roadmap for HCV therapy that starts with PR and takes into account those DAAs already approved in some Asian countries can provide guidance as to the best strategies for management, particularly of genotype 1 and 3 infections, based on SVR rates. Sofosbuvir and PR are likely to be the initial therapies for genotype 1 and 3 disease, although in the former these drugs may be suboptimal in patients with cirrhosis (62% SVR) and the extension of treatment to 24 weeks may be required. For difficult to treat genotype 3 infections in treatment-experienced patients with cirrhosis, a combination of sofosbuvir and PR result in an 83% SVR and is, therefore, currently the optimal treatment regimen. Treatment failure is best avoided since data on rescue therapies for DAA failure are still incomplete.

Interferon-Free Treatment of Hepatitis C Virus in HIV/Hepatitis C Virus-Coinfected Subjects Results in Increased Serum Low-Density Lipoprotein Concentration

PubMed Central

Townsend, Kerry; Meissner, Eric G.; Sidharthan, Sreetha; Sampson, Maureen; Remaley, Alan T.; Tang, Lydia; Kohli, Anita; Osinusi, Anu; Masur, Henry

2016-01-01

Abstract Chronic hepatitis C virus (HCV) infection is associated with lower serum concentration of low-density lipoprotein (LDL-C), the primary cholesterol metabolite targeted pharmaceutically to modulate cardiovascular risk. Chronic infection with human immunodeficiency virus (HIV) and treatment with antiretrovirals (ARVs) are associated with dyslipidemia and increased risk of cardiovascular disease. In subjects coinfected with HIV and HCV, lipid abnormalities associated with either infection alone are often attenuated. Treatment of chronic HCV infection in HIV/HCV-coinfected subjects is now possible with interferon (IFN)-free regimens composed of directly acting antivirals (DAAs). We previously observed a marked increase in serum LDL-C in HCV-monoinfected subjects treated with sofosbuvir and ribavirin (SOF/RBV) that correlated with viral decline in serum, suggesting a direct influence of HCV clearance on serum cholesterol. In the present study, we assessed longitudinal changes in cholesterol in HIV/HCV-coinfected subjects during treatment of HCV genotype-1 (GT1) infection with combination DAA therapy. We report a rapid increase in LDL-C and LDL particle size by week 2 of treatment that was sustained during and after treatment in HIV/HCV-coinfected subjects. No change in serum LDL-C was observed at day 3 of treatment, in spite of a marked reduction in serum HCV viral load, suggesting LDL-C increases do not directly reflect HCV clearance as measured in peripheral blood. After effective DAA therapy for HCV, an increase in LDL should be anticipated in HIV/HCV-coinfected subjects. PMID:26559180

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rong, Libin; Guedj, Jeremie; Dahari, Harel

The current paradigm for studying hepatitis C virus (HCV) dynamics in patients utilizes a standard viral dynamic model that keeps track of uninfected (target) cells, infected cells, and virus. The model does not account for the dynamics of intracellular viral replication, which is the major target of direct-acting antiviral agents (DAAs). In this paper, we describe and study a recently developed multiscale age-structured model that explicitly considers the potential effects of DAAs on intracellular viral RNA production, degradation, and secretion as virus into the circulation. We show that when therapy significantly blocks both intracellular viral RNA production and virus secretion,more » the serum viral load decline has three phases, with slopes reflecting the rate of serum viral clearance, the rate of loss of intracellular viral RNA, and the rate of loss of intracellular replication templates and infected cells, respectively. We also derive analytical approximations of the multiscale model and use one of them to analyze data from patients treated for 14 days with the HCV protease inhibitor danoprevir. Analysis suggests that danoprevir significantly blocks intracellular viral production (with mean effectiveness 99.2%), enhances intracellular viral RNA degradation about 5-fold, and moderately inhibits viral secretion (with mean effectiveness 56%). Finally, the multiscale model can be used to study viral dynamics in patients treated with other DAAs and explore their mechanisms of action in treatment of hepatitis C.« less

Antiviral drug research proposal activity.

PubMed

Injaian, Lisa; Smith, Ann C; Shipley, Jennifer German; Marbach-Ad, Gili; Fredericksen, Brenda

2011-01-01

The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an "expert" in one aspect of the project. The Antiviral Drug Research Proposal (ADRP) culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity.

Consensus statement on the management of patients with HCV infection in Romania

PubMed Central

Ancuța, Ioan

2017-01-01

Background HCV direct-acting antivirals (DAAs) have made treatment easier for both patients and healthcare practitioners, but have also brought new challenges in terms of patient management and monitoring prior to, during, and after treatment. Methods To sum up and unify the clinical experience of Romanian DAA prescribing physicians, we have organized a Consensus Meeting in November 2016 in Bucharest, Romania. Consensus Statement The Consensus Meeting has provided expert answers to ten significant questions regarding HCV infection, namely: How do we diagnose patients with HCV infection? How do we stage liver disease in patients with HCV infection? How do we monitor patients with HCV infection prior to treatment? Which patients with HCV infection do we treat? When do we start treatment for HCV infection? What regimens do we use for treating HCV infection? How do we monitor patients with HCV infection during treatment? What adverse events should we expect during treatment of HCV infection and how do we prevent/manage them? How do we monitor patients with HCV infection after treatment? How do we expect the landscape of HCV to change in the following years? PMID:28331840

Newer influenza antivirals, biotherapeutics and combinations

PubMed Central

Hayden, Frederick G.

2012-01-01

Please cite this paper as: Hayden FG. (2012) Newer Influenza Antivirals, Biotherapeutics and Combinations. Influenza and Other Respiratory Viruses 7(Suppl. 1), 63–75. This summary provides an overview of investigational antiviral agents for influenza and of future directions for development of influenza therapeutics. While progress in developing clinically useful antiviral agents for influenza has been generally slow, especially with respect to seriously ill and high‐risk patients, important clinical studies of intravenous neuraminidase inhibitors, antibodies and drug combinations are currently in progress. The current decade offers the promise of developing small molecular weight inhibitors with novel mechanisms of action, including host‐directed therapies, new biotherapeutics and drug combinations, that should provide more effective antiviral therapies and help mitigate the problem of antiviral resistance. Immunomodulatory interventions also offer promise but need to be based on better understanding of influenza pathogenesis, particularly in seriously ill patients. The development of combination interventions, immunomodulators and host‐directed therapies presents unique clinical trial design and regulatory hurdles that remain to be addressed. PMID:23279899

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Lockhart, Pauline; Daly, Fergus; Pitkethly, Marie; Comerford, Natalia; Sullivan, Frank

2009-10-07

Antiviral agents against herpes simplex virus are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but their effectiveness is uncertain. Significant morbidity can be associated with severe cases. This review addresses the effect of antiviral therapy on Bell's palsy. We updated the search of the Cochrane Neuromuscular Disease Group Trials Register (December 2008), MEDLINE (from January 1966 to December 8 2008), EMBASE (from January 1980 to December 8 2008) and LILACS (from January 1982 to December 2008). Randomized trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. Twenty-three papers were selected for consideration. Seven trials including 1987 participants met the inclusion criteria, adding five studies to the two in the previous review.Incomplete recovery at one year. There was no significant benefit in the rate of incomplete recovery from antivirals compared with placebo (n = 1886, RR 0.88, 95% CI 0.65 to 1.18). In meta-analyses with some unexplained heterogeneity, the outcome with antivirals was significantly worse than with corticosteroids (n = 768, RR 2.82, 95% CI 1.09 to 7.32) and the outcome with antivirals plus corticosteroids was significantly better than with placebo (n = 658, RR 0.56, 95% CI 0.41 to 0.76).Motor synkinesis or crocodile tears at one year. In single trials, there was no significant difference in long term sequelae comparing antivirals and corticosteroids with corticosteroids alone (n = 99, RR 0.39, 95% CI 0.14 to 1.07) or antivirals with corticosteroids (n = 101, RR 1.03, 95% CI 0.51 to 2.07).Adverse events.There was no significant difference in rates of adverse events between antivirals and placebo (n = 1544, RR 1.06, 95% CI 0.81 to 1.38), between antivirals and corticosteroids (n = 667, RR 0.96, 95% CI 0.65 to 1.41) or between the antiviral-corticosteroid combination and placebo (n = 658, RR 1.15, 95% CI 0.79 to 1.66). High quality evidence showed no

Hepatitis C Virus in Kidney Transplant Recipients: A Problem on the Path to Eradication.

PubMed

Suarez Benjumea, A; Gonzalez-Corvillo, C; Sousa, J M; Bernal Blanco, G; Suñer Poblet, M; Perez Valdivia, M A; Gonzalez Roncero, F M; Acevedo, P; Gentil Govantez, M A

2016-11-01

Hepatitis C virus (HCV) still has significant prevalence in kidney transplant (KT) recipients and is related to poor recipient and graft survival. New direct-acting antivirals (DAA) are leading to a radical change in the problem. We studied HCV prevalence at the time of transplantation and in follow-up patients, the way cases are handled, and the results of DAA. A total of 2,001 KT had been performed in our center since 1978. Pre- or post-transplantation HCV serology was present in 1,880 cases and was positive in 13.4%. A total of 1,195 transplant recipients were still being monitored by us, with only 60 (5%) HCV+ and 45 (3.6%) RNA+ cases. Of these 45 HCV+/RNA+, 25 had been or were being treated, 7 were about to begin treatment, 1 was awaiting new DAA treatment owing to low glomerular filtration rate (GFR), 3 were being evaluated, 2 had been excluded owing to high comorbidity, 2 refused to be treated, 2 needed to return to hemodialysis, and 1 was lost to follow-up. Except 1 case where Viekira Pak was used because of low GFR, all cases included sofosbuvir as the main drug associated with either ledipasvir (70%) or daclatasvir (25%). Ribavirin was added as coadjuvant in 35% of cases. Twenty-one patients had completed treatment (84%). Two patients had to interrupt DAA therapy (8%), one because of hepatotoxicity and the other as a result of a liver transplantation. In every case, the graft maintained function and negativization of viral replication occurred. Side effects have been low, anemia related to ribavirin being the main one. Just one case needed to be interrupted at the 7th week of DAA therapy due to hepatotoxicity. It has frequently been necessary to adjust immunosuppression treatment with the use of higher doses of tacrolimus. Copyright © 2016 Elsevier Inc. All rights reserved.

What You Should Know about Flu Antiviral Drugs

MedlinePlus

... Other What You Should Know About Flu Antiviral Drugs Language: English (US) Español Recommend on Facebook Tweet ... used to treat flu illness. What are antiviral drugs? Antiviral drugs are prescription medicines (pills, liquid, an ...

Viruses and Antiviral Immunity in Drosophila

PubMed Central

Xu, Jie; Cherry, Sara

2013-01-01

Viral pathogens present many challenges to organisms, driving the evolution of a myriad of antiviral strategies to combat infections. A wide variety of viruses infect invertebrates, including both natural pathogens that are insect-restricted, and viruses that are transmitted to vertebrates. Studies using the powerful tools available in the model organism Drosophila have expanded our understanding of antiviral defenses against diverse viruses. In this review, we will cover three major areas. First, we will describe the tools used to study viruses in Drosophila. Second, we will survey the major viruses that have been studied in Drosophila. And lastly, we will discuss the well-characterized mechanisms that are active against these diverse pathogens, focusing on non-RNAi mediated antiviral mechanisms. Antiviral RNAi is discussed in another paper in this issue. PMID:23680639

Antiviral Lectins: Selective Inhibitors of Viral Entry

PubMed Central

Mitchell, Carter A.; Ramessar, Koreen; O’Keefe, Barry R.

2017-01-01

Many natural lectins have been reported to have antiviral activity. As some of these have been put forward as potential development candidates for preventing or treating viral infections, we have set out in this review to survey the literature on antiviral lectins. The review groups lectins by structural class and class of source organism we also detail their carbohydrate specificity and their reported antiviral activities. The review concludes with a brief discussion of several of the pertinent hurdles that heterologous proteins must clear to be useful clinical candidates and cites examples where such studies have been reported for antiviral lectins. Though the clearest path currently being followed is the use of antiviral lectins as anti-HIV microbicides via topical mucosal administration, some investigators have also found systemic efficacy against acute infections following subcutaneous administration. PMID:28322922

Long-term outcomes of direct acting antivirals in post-transplant advanced hepatitis C virus recurrence and fibrosing cholestatic hepatitis.

PubMed

Vukotic, R; Conti, F; Fagiuoli, S; Morelli, M C; Pasulo, L; Colpani, M; Foschi, F G; Berardi, S; Pianta, P; Mangano, M; Donato, M F; Malinverno, F; Monico, S; Tamè, M; Mazzella, G; Belli, L S; Viganò, R; Carrai, P; Burra, P; Russo, F P; Lenci, I; Toniutto, P; Merli, M; Loiacono, L; Iemmolo, R; Degli Antoni, A M; Romano, A; Picciotto, A; Rendina, M; Andreone, P

2017-10-01

Long-term functional outcomes of sofosbuvir-based antiviral treatment were evaluated in a cohort study involving 16 Italian centres within the international compassionate use programme for post-transplant hepatitis C virus (HCV) recurrence. Seventy-three patients with cirrhosis (n=52) or fibrosing cholestatic hepatitis (FCH, n=21) received 24-week sofosbuvir with ribavirin±pegylated interferon or interferon-free sofosbuvir-based regimen with daclatasvir/simeprevir+ribavirin. The patients were observed for a median time of 103 (82-112) weeks. Twelve of 73 (16.4%) died (10 non-FCH, 2 FCH) and two underwent re-LT. Sustained virological response was achieved in 46 of 66 (69.7%): 31 of 47 (66%) non-FCH and 15 of 19 (79%) FCH patients. All relapsers were successfully retreated. Comparing the data of baseline with last follow-up, MELD and Child-Turcotte-Pugh scores improved both in non-FCH (15.3±6.5 vs 10.5±3.8, P<.0001 and 8.4±2.1 vs 5.7±1.3, P<.0001, respectively) and FCH (17.3±5.9 vs 10.1±2.8, P=.001 and 8.2±1.6 vs 5.5±1, P=.001, respectively). Short-treatment mortality was higher in patients with baseline MELD≥25 than in those with MELD<25 (42.9% vs 4.8%, P=.011). Long-term mortality was 53.3% among patients with baseline MELD≥20 and 7.5% among those with MELD<20 (P<.0001). Among deceased patients 75% were Child-Turcotte-Pugh class C at baseline, while among survivors 83.9% were class A or B (P<.0001). Direct acting antivirals-based treatments for severe post-transplant hepatitis C recurrence, comprising fibrosing cholestatic hepatitis, significantly improve liver function, even without viral clearance and permit an excellent long-term survival. The setting of severe HCV recurrence may require the identification of "too-sick-to-treat patients" to avoid futile treatments. © 2017 John Wiley & Sons Ltd.

Intervention Packages to Reduce the Impact of HIV and HCV Infections Among People Who Inject Drugs in Eastern Europe and Central Asia: A Modeling and Cost-effectiveness Study.

PubMed

Mabileau, Guillaume; Scutelniciuc, Otilia; Tsereteli, Maia; Konorazov, Ivan; Yelizaryeva, Alla; Popovici, Svetlana; Saifuddin, Karimov; Losina, Elena; Manova, Manoela; Saldanha, Vinay; Malkin, Jean-Elie; Yazdanpanah, Yazdan

2018-03-01

We evaluated the effectiveness and cost-effectiveness of interventions targeting hepatitis C virus (HCV) and HIV infections among people who inject drugs (PWID) in Eastern Europe/Central Asia. We specifically considered the needle-syringe program (NSP), opioid substitution therapy (OST), HCV and HIV diagnosis, antiretroviral therapy (ART), and/or new HCV treatment (direct acting antiviral [DAA]) in Belarus, Georgia, Kazakhstan, Republic of Moldova, and Tajikistan. We developed a deterministic dynamic compartmental model and evaluated the number of infections averted, costs, and incremental cost-effectiveness ratios (ICERs) of interventions. OST decreased frequencies of injecting by 85% and NSP needle sharing rates by 57%; ART was introduced at CD4 <350 and DAA at fibrosis stage ≥F2 at a $2370 to $23 280 cost. Increasing NSP+OST had a high impact on transmissions (infections averted in PWID: 42% in Tajikistan to 55% in Republic of Moldova for HCV; 30% in Belarus to 61% in Kazakhstan for HIV over 20 years). Increasing NSP+OST+ART was very cost-effective in Georgia (ICER = $910/year of life saved [YLS]), and was cost-saving in Kazakhstan and Republic of Moldova. NSP+OST+ART and HIV diagnosis was very cost-effective in Tajikistan (ICER = $210/YLS). Increasing the coverage of all interventions was always the most effective strategy and was cost-effective in Belarus and Kazakhstan (ICER = $12 960 and $21 850/YLS); it became cost-effective/cost-saving in all countries when we decreased DAA costs. Increasing NSP+OST coverage, in addition to ART and HIV diagnosis, had a high impact on both epidemics and was very cost-effective and even cost-saving. When HCV diagnosis was improved, increased DAA averted a high number of new infections if associated with NSP+OST.

Analysis of hepatitis C NS5A resistance associated polymorphisms using ultra deep single molecule real time (SMRT) sequencing.

PubMed

Bergfors, Assar; Leenheer, Daniël; Bergqvist, Anders; Ameur, Adam; Lennerstrand, Johan

2016-02-01

Development of Hepatitis C virus (HCV) resistance against direct-acting antivirals (DAAs), including NS5A inhibitors, is an obstacle to successful treatment of HCV when DAAs are used in sub-optimal combinations. Furthermore, it has been shown that baseline (pre-existing) resistance against DAAs is present in treatment naïve-patients and this will potentially complicate future treatment strategies in different HCV genotypes (GTs). Thus the aim was to detect low levels of NS5A resistant associated variants (RAVs) in a limited sample set of treatment-naïve patients of HCV GT1a and 3a, since such polymorphisms can display in vitro resistance as high as 60000 fold. Ultra-deep single molecule real time (SMRT) sequencing with the Pacific Biosciences (PacBio) RSII instrument was used to detect these RAVs. The SMRT sequencing was conducted on ten samples; three of them positive with Sanger sequencing (GT1a Q30H and Y93N, and GT3a Y93H), five GT1a samples, and two GT3a non-positive samples. The same methods were applied to the HCV GT1a H77-plasmid in a dilution series, in order to determine the error rates of replication, which in turn was used to determine the limit of detection (LOD), as defined by mean + 3SD, of minority variants down to 0.24%. We found important baseline NS5A RAVs at levels between 0.24 and 0.5%, which could potentially have clinical relevance. This new method with low level detection of baseline RAVs could be useful in predicting the most cost-efficient combination of DAA treatment, and reduce the treatment duration for an HCV infected individual. Copyright © 2015 Elsevier B.V. All rights reserved.

Viruses and antiviral immunity in Drosophila.

PubMed

Xu, Jie; Cherry, Sara

2014-01-01

Viral pathogens present many challenges to organisms, driving the evolution of a myriad of antiviral strategies to combat infections. A wide variety of viruses infect invertebrates, including both natural pathogens that are insect-restricted, and viruses that are transmitted to vertebrates. Studies using the powerful tools in the model organism Drosophila have expanded our understanding of antiviral defenses against diverse viruses. In this review, we will cover three major areas. First, we will describe the tools used to study viruses in Drosophila. Second, we will survey the major viruses that have been studied in Drosophila. And lastly, we will discuss the well-characterized mechanisms that are active against these diverse pathogens, focusing on non-RNAi mediated antiviral mechanisms. Antiviral RNAi is discussed in another paper in this issue. Copyright © 2013 Elsevier Ltd. All rights reserved.

Activation of cGAS-dependent antiviral responses by DNA intercalating agents

PubMed Central

Pépin, Geneviève; Nejad, Charlotte; Thomas, Belinda J.; Ferrand, Jonathan; McArthur, Kate; Bardin, Philip G.; Williams, Bryan R.G.; Gantier, Michael P.

2017-01-01

Acridine dyes, including proflavine and acriflavine, were commonly used as antiseptics before the advent of penicillins in the mid-1940s. While their mode of action on pathogens was originally attributed to their DNA intercalating activity, work in the early 1970s suggested involvement of the host immune responses, characterized by induction of interferon (IFN)-like activities through an unknown mechanism. We demonstrate here that sub-toxic concentrations of a mixture of acriflavine and proflavine instigate a cyclic-GMP-AMP (cGAMP) synthase (cGAS)-dependent type-I IFN antiviral response. This pertains to the capacity of these compounds to induce low level DNA damage and cytoplasmic DNA leakage, resulting in cGAS-dependent cGAMP-like activity. Critically, acriflavine:proflavine pre-treatment of human primary bronchial epithelial cells significantly reduced rhinovirus infection. Collectively, our findings constitute the first evidence that non-toxic DNA binding agents have the capacity to act as indirect agonists of cGAS, to exert potent antiviral effects in mammalian cells. PMID:27694309

Negative regulation of RIG-I-mediated antiviral signaling by TRK-fused gene (TFG) protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Na-Rae; Shin, Han-Bo; Kim, Hye-In

2013-07-19

Highlights: •TRK-fused gene product (TFG) interacts with TRIM25 upon viral infection. •TFG negatively regulates RIG-I mediated antiviral signaling. •TFG depletion leads to enhanced viral replication. •TFG act downstream of MAVS. -- Abstract: RIG-I (retinoic acid inducible gene I)-mediated antiviral signaling serves as the first line of defense against viral infection. Upon detection of viral RNA, RIG-I undergoes TRIM25 (tripartite motif protein 25)-mediated K63-linked ubiquitination, leading to type I interferon (IFN) production. In this study, we demonstrate that TRK-fused gene (TFG) protein, previously identified as a TRIM25-interacting protein, binds TRIM25 upon virus infection and negatively regulates RIG-I-mediated type-I IFN signaling. RIG-I-mediatedmore » IFN production and nuclear factor (NF)-κB signaling pathways were upregulated by the suppression of TFG expression. Furthermore, vesicular stomatitis virus (VSV) replication was significantly inhibited by small inhibitory hairpin RNA (shRNA)-mediated knockdown of TFG, supporting the suppressive role of TFG in RIG-I-mediated antiviral signaling. Interestingly, suppression of TFG expression increased not only RIG-I-mediated signaling but also MAVS (mitochondrial antiviral signaling protein)-induced signaling, suggesting that TFG plays a pivotal role in negative regulation of RNA-sensing, RIG-I-like receptor (RLR) family signaling pathways.« less

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-11-09

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. This review was first published in 2001 and revised several times, most recently in 2009. This version replaces an update of the review in Issue 7 of the Cochrane Library subsequently withdrawn because of an ongoing investigation into the reliability of data from an included study. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Ten trials, including 2280 participants, met the inclusion criteria and are included in the final analysis. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found a significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.61, 95% confidence interval (CI) 0.39 to 0.97, n = 1315). For people with severe Bell

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-07-01

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.47 to 1.02, n = 1715). For people with severe Bell's palsy (House-Brackmann scores of 5 and 6 or the equivalent in other scales), we found a reduction in the rate of incomplete recovery at month six when antivirals plus corticosteroids were used (RR 0.64, 95% CI 0.41 to 0

Virus-encoded chemokine receptors--putative novel antiviral drug targets.

PubMed

Rosenkilde, Mette M

2005-01-01

Large DNA viruses, in particular herpes- and poxviruses, have evolved proteins that serve as mimics or decoys for endogenous proteins in the host. The chemokines and their receptors serve key functions in both innate and adaptive immunity through control of leukocyte trafficking, and have as such a paramount role in the antiviral immune responses. It is therefore not surprising that viruses have found ways to exploit and subvert the chemokine system by means of molecular mimicry. By ancient acts of molecular piracy and by induction and suppression of endogenous genes, viruses have utilized chemokines and their receptors to serve a variety of roles in viral life-cycle. This review focuses on the pharmacology of virus-encoded chemokine receptors, yet also the family of virus-encoded chemokines and chemokine-binding proteins will be touched upon. Key properties of the virus-encoded receptors, compared to their closest endogenous homologs, are interactions with a wider range of chemokines, which can act as agonists, antagonists and inverse agonists, and the exploitation of many signal transduction pathways. High constitutive activity is another key property of some--but not all--of these receptors. The chemokine receptors belong to the superfamily of G-protein coupled 7TM receptors that per se are excellent drug targets. At present, non-peptide antagonists have been developed against many chemokine receptors. The potentials of the virus-encoded chemokine receptors as drug targets--ie. as novel antiviral strategies--will be highlighted here together with the potentials of the virus-encoded chemokines and chemokine-binding proteins as novel anti-inflammatory biopharmaceutical strategies.

Viral ancestors of antiviral systems.

PubMed

Villarreal, Luis P

2011-10-01

All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the 'Big Bang' theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

Newer influenza antivirals, biotherapeutics and combinations.

PubMed

Hayden, Frederick G

2013-01-01

This summary provides an overview of investigational antiviral agents for influenza and of future directions for development of influenza therapeutics. While progress in developing clinically useful antiviral agents for influenza has been generally slow, especially with respect to seriously ill and high-risk patients, important clinical studies of intravenous neuraminidase inhibitors, antibodies and drug combinations are currently in progress. The current decade offers the promise of developing small molecular weight inhibitors with novel mechanisms of action, including host-directed therapies, new biotherapeutics and drug combinations, that should provide more effective antiviral therapies and help mitigate the problem of antiviral resistance. Immunomodulatory interventions also offer promise but need to be based on better understanding of influenza pathogenesis, particularly in seriously ill patients. The development of combination interventions, immunomodulators and host-directed therapies presents unique clinical trial design and regulatory hurdles that remain to be addressed. © 2012 Blackwell Publishing Ltd.

Nanoparticulate delivery systems for antiviral drugs.

PubMed

Lembo, David; Cavalli, Roberta

2010-01-01

Nanomedicine opens new therapeutic avenues for attacking viral diseases and for improving treatment success rates. Nanoparticulate-based systems might change the release kinetics of antivirals, increase their bioavailability, improve their efficacy, restrict adverse drug side effects and reduce treatment costs. Moreover, they could permit the delivery of antiviral drugs to specific target sites and viral reservoirs in the body. These features are particularly relevant in viral diseases where high drug doses are needed, drugs are expensive and the success of a therapy is associated with a patient's adherence to the administration protocol. This review presents the current status in the emerging area of nanoparticulate delivery systems in antiviral therapy, providing their definition and description, and highlighting some peculiar features. The paper closes with a discussion on the future challenges that must be addressed before the potential of nanotechnology can be translated into safe and effective antiviral formulations for clinical use.

Antiviral activity of silymarin against chikungunya virus

PubMed Central

Lani, Rafidah; Hassandarvish, Pouya; Chiam, Chun Wei; Moghaddam, Ehsan; Chu, Justin Jang Hann; Rausalu, Kai; Merits, Andres; Higgs, Stephen; Vanlandingham, Dana; Abu Bakar, Sazaly; Zandi, Keivan

2015-01-01

The mosquito-borne chikungunya virus (CHIKV) causes chikungunya fever, with clinical presentations such as severe back and small joint pain, and debilitating arthritis associated with crippling pains that persist for weeks and even years. Although there are several studies to evaluate the efficacy of drugs against CHIKV, the treatment for chikungunya fever is mainly symptom-based and no effective licensed vaccine or antiviral are available. Here, we investigated the antiviral activity of three types of flavonoids against CHIKV in vitro replication. Three compounds: silymarin, quercetin and kaempferol were evaluated for their in vitro antiviral activities against CHIKV using a CHIKV replicon cell line and clinical isolate of CHIKV of Central/East African genotype. A cytopathic effect inhibition assay was used to determine their activities on CHIKV viral replication and quantitative reverse transcription PCR was used to calculate virus yield. Antiviral activity of effective compound was further investigated by evaluation of CHIKV protein expression using western blotting for CHIKV nsP1, nsP3, and E2E1 proteins. Briefly, silymarin exhibited significant antiviral activity against CHIKV, reducing both CHIKV replication efficiency and down-regulating production of viral proteins involved in replication. This study may have important consequence for broaden the chance of getting the effective antiviral for CHIKV infection. PMID:26078201

Antiviral Natural Products and Herbal Medicines

PubMed Central

Lin, Liang-Tzung; Hsu, Wen-Chan; Lin, Chun-Ching

2014-01-01

Viral infections play an important role in human diseases, and recent outbreaks in the advent of globalization and ease of travel have underscored their prevention as a critical issue in safeguarding public health. Despite the progress made in immunization and drug development, many viruses lack preventive vaccines and efficient antiviral therapies, which are often beset by the generation of viral escape mutants. Thus, identifying novel antiviral drugs is of critical importance and natural products are an excellent source for such discoveries. In this mini-review, we summarize the antiviral effects reported for several natural products and herbal medicines. PMID:24872930

Fatty liver in hepatitis C patients post-sustained virological response with direct-acting antivirals

PubMed Central

Noureddin, Mazen; Wong, Micaela M; Todo, Tsuyoshi; Lu, Shelly C; Sanyal, Arun J; Mena, Edward A

2018-01-01

AIM To determine steatosis and fibrosis prevalence in hepatitis C patients after a sustained virological response achieved with direct-acting antivirals. METHODS Transient elastography with controlled attenuation parameter (CAP) was used to assess hepatic steatosis post-sustained virological response (SVR); the CAP technology was not available in the United States at study initiation. Liver stiffness/fibrosis was measured before and 47 wk after treatment completion. Patients with genotype 3 and patients with cirrhosis were excluded. RESULTS One hundred and one patients were included in the study. Post-SVR there were decreases from baseline in alanine aminotransferase (ALT) (63.1 to 17.8 U/L), aspartate aminotransferase (51.8 to 21.5 U/L) and fibrosis score (7.4 to 6.1 kPa) (P < 0.05). Post-SVR, 48 patients (47.5%) had steatosis on CAP; of these, 6.25% had advanced fibrosis. Patients with steatosis had higher body mass index (29.0 vs 26.1 kg/m2), glucose (107.8 vs 96.6 mg/dL), ALT (20.4 vs 15.3 mg/dL), CAP score (296.3 vs 212.4 dB/m) and fibrosis score (7.0 vs 5.3 kPa); P < 0.05. Interestingly, compared to baseline, both patients with and without steatosis had change in fibrosis score post-SVR (7.7 kPa vs 7.0 kPa and 7.0 kPa vs 5.3 kPa); alternatively, (P < 0.05) and therefore patients with steatosis continued to have clinically significant stiffness (≥ 7 kPa). CONCLUSION Fatty liver is very common in hepatitis C virus (HCV) patients post-SVR. These patients continue to have elevated mean fibrosis score (≥ 7 kPa) compared to those without fatty liver; some have advanced fibrosis. Long term follow up is needed to assess steatosis and fibrosis in HCV patients post-SVR. PMID:29568207

Fatty liver in hepatitis C patients post-sustained virological response with direct-acting antivirals.

PubMed

Noureddin, Mazen; Wong, Micaela M; Todo, Tsuyoshi; Lu, Shelly C; Sanyal, Arun J; Mena, Edward A

2018-03-21

To determine steatosis and fibrosis prevalence in hepatitis C patients after a sustained virological response achieved with direct-acting antivirals. Transient elastography with controlled attenuation parameter (CAP) was used to assess hepatic steatosis post-sustained virological response (SVR); the CAP technology was not available in the United States at study initiation. Liver stiffness/fibrosis was measured before and 47 wk after treatment completion. Patients with genotype 3 and patients with cirrhosis were excluded. One hundred and one patients were included in the study. Post-SVR there were decreases from baseline in alanine aminotransferase (ALT) (63.1 to 17.8 U/L), aspartate aminotransferase (51.8 to 21.5 U/L) and fibrosis score (7.4 to 6.1 kPa) ( P < 0.05). Post-SVR, 48 patients (47.5%) had steatosis on CAP; of these, 6.25% had advanced fibrosis. Patients with steatosis had higher body mass index (29.0 vs 26.1 kg/m 2 ), glucose (107.8 vs 96.6 mg/dL), ALT (20.4 vs 15.3 mg/dL), CAP score (296.3 vs 212.4 dB/m) and fibrosis score (7.0 vs 5.3 kPa); P < 0.05. Interestingly, compared to baseline, both patients with and without steatosis had change in fibrosis score post-SVR (7.7 kPa vs 7.0 kPa and 7.0 kPa vs 5.3 kPa); alternatively, ( P < 0.05) and therefore patients with steatosis continued to have clinically significant stiffness (≥ 7 kPa). Fatty liver is very common in hepatitis C virus (HCV) patients post-SVR. These patients continue to have elevated mean fibrosis score (≥ 7 kPa) compared to those without fatty liver; some have advanced fibrosis. Long term follow up is needed to assess steatosis and fibrosis in HCV patients post-SVR.

Antiviral Drug Research Proposal Activity †

PubMed Central

Injaian, Lisa; Smith, Ann C.; Shipley, Jennifer German; Marbach-Ad, Gili; Fredericksen, Brenda

2011-01-01

The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an “expert” in one aspect of the project. The Antiviral Drug Research Proposal (ADRP) culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity. PMID:23653735

Viral Ancestors of Antiviral Systems

PubMed Central

Villarreal, Luis P.

2011-01-01

All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the ‘Big Bang’ theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features. PMID:22069523

3,7-Dideazaneplanocin: Synthesis and antiviral analysis.

PubMed

Yin, Xue-Qiang; Schneller, Stewart W

2017-12-01

Objective To synthesize 3,7-dideazaneplanocin and evaluate its antiviral potential. Methods The target 3,7-dideazaneplanocin has been prepared in five steps from a readily available cyclopentenol. A thorough in vitro antiviral analysis was conducted versus both DNA and RNA viruses. Results A rational synthesis of 3,7-dideazaneplanocin was conceived and successfully pursued in such a way that it can be adapted to various analogs of 3,7-dideazaneplanocin. Using standard antiviral assays, no activity for 3,7-dideazaneplanocn was found. Conclusion Two structural features are necessary for adenine-based carbocyclic nucleosides (like neplanocin) for potential antiviral properties: (i) inhibition of S-adenosylhomocysteine hydrolase and/or (ii) C-5' activation via the mono-nucleotide. These two requisite adenine structural features to fit these criteria are not present in in the target 3,7-dideazaneplanocin: (i) an N-7 is necessary for inhibition of the hydrolase and the N-3 is claimed to be essential for phosphorylation at C-5'. Thus, it is not surprising that 3,7-dideazaneplaoncin lacked antiviral properties.

Immune Receptors and Co-receptors in Antiviral Innate Immunity in Plants.

PubMed

Gouveia, Bianca C; Calil, Iara P; Machado, João Paulo B; Santos, Anésia A; Fontes, Elizabeth P B

2016-01-01

Plants respond to pathogens using an innate immune system that is broadly divided into PTI (pathogen-associated molecular pattern- or PAMP-triggered immunity) and ETI (effector-triggered immunity). PTI is activated upon perception of PAMPs, conserved motifs derived from pathogens, by surface membrane-anchored pattern recognition receptors (PRRs). To overcome this first line of defense, pathogens release into plant cells effectors that inhibit PTI and activate effector-triggered susceptibility (ETS). Counteracting this virulence strategy, plant cells synthesize intracellular resistance (R) proteins, which specifically recognize pathogen effectors or avirulence (Avr) factors and activate ETI. These coevolving pathogen virulence strategies and plant resistance mechanisms illustrate evolutionary arms race between pathogen and host, which is integrated into the zigzag model of plant innate immunity. Although antiviral immune concepts have been initially excluded from the zigzag model, recent studies have provided several lines of evidence substantiating the notion that plants deploy the innate immune system to fight viruses in a manner similar to that used for non-viral pathogens. First, most R proteins against viruses so far characterized share structural similarity with antibacterial and antifungal R gene products and elicit typical ETI-based immune responses. Second, virus-derived PAMPs may activate PTI-like responses through immune co-receptors of plant PTI. Finally, and even more compelling, a viral Avr factor that triggers ETI in resistant genotypes has recently been shown to act as a suppressor of PTI, integrating plant viruses into the co-evolutionary model of host-pathogen interactions, the zigzag model. In this review, we summarize these important progresses, focusing on the potential significance of antiviral immune receptors and co-receptors in plant antiviral innate immunity. In light of the innate immune system, we also discuss a newly uncovered layer of

Identification of Inonotus obliquus polysaccharide with broad-spectrum antiviral activity against multi-feline viruses.

PubMed

Tian, Jin; Hu, Xiaoliang; Liu, Dafei; Wu, Hongxia; Qu, Liandong

2017-02-01

Inonotus obliquus polysaccharides (IOPs) are a potential drug for the prevention and treatment of cancer, cardiopathy, diabetes, AIDs, pancreatitis and other diseases. In this study, we found that IOP can act as a broad-spectrum antiviral drug against feline viruses in the in vitro experiment. Using cell models of feline calicivirus (FCV), we demonstrated that IOP treatment was capable of exhibiting anti-FCV strain F9 activity in cell-based assays and also showed low cytotoxicity. Investigation of the mechanism of action of the compound revealed that IOP treatment induces its inhibitory actions directly on virus particles through blocking viral binding/absorpting. The inhibitory activity against other FCV isolates from China was also identified. More importantly, we found that IOP exhibited broad-spectrum antiviral activity against the feline herpesvirus 1, feline influenza virus H3N2 and H5N6, feline panleukopenia virus and feline infectious peritonitis virus that can contribute to respiratory and gastrointestinal diseases in cats. These findings suggest that IOP may be a potential broad-spectrum antiviral drug against feline viruses. Copyright © 2016 Elsevier B.V. All rights reserved.

Systems biology: A tool for charting the antiviral landscape.

PubMed

Bowen, James R; Ferris, Martin T; Suthar, Mehul S

2016-06-15

The host antiviral programs that are initiated following viral infection form a dynamic and complex web of responses that we have collectively termed as "the antiviral landscape". Conventional approaches to studying antiviral responses have primarily used reductionist systems to assess the function of a single or a limited subset of molecules. Systems biology is a holistic approach that considers the entire system as a whole, rather than individual components or molecules. Systems biology based approaches facilitate an unbiased and comprehensive analysis of the antiviral landscape, while allowing for the discovery of emergent properties that are missed by conventional approaches. The antiviral landscape can be viewed as a hierarchy of complexity, beginning at the whole organism level and progressing downward to isolated tissues, populations of cells, and single cells. In this review, we will discuss how systems biology has been applied to better understand the antiviral landscape at each of these layers. At the organismal level, the Collaborative Cross is an invaluable genetic resource for assessing how genetic diversity influences the antiviral response. Whole tissue and isolated bulk cell transcriptomics serves as a critical tool for the comprehensive analysis of antiviral responses at both the tissue and cellular levels of complexity. Finally, new techniques in single cell analysis are emerging tools that will revolutionize our understanding of how individual cells within a bulk infected cell population contribute to the overall antiviral landscape. Copyright © 2016 Elsevier B.V. All rights reserved.

Antiviral therapy for hepatitis C: Has anything changed for pregnant/lactating women?

PubMed Central

Spera, Anna Maria; Eldin, Tarek Kamal; Tosone, Grazia; Orlando, Raffaele

2016-01-01

Hepatitis C virus (HCV) affects about 3% of the world’s population, with the highest prevalence in individuals under 40. The prevalence in pregnant women varies with geographical distribution (highest in developing countries). Prevalence also increases in sub-populations of women at high risk for blood-transmitted infections. HCV infection in pregnancy represents a non-negligible problem. However, most of the past antiviral regimens cannot be routinely offered to pregnant or breastfeeding women because of their side effects. We briefly reviewed the issue of treatment of HCV infection in pregnant/breastfeeding women focusing on the effects of the new direct-acting antivirals on fertility, pregnancy and lactation in animal studies and on the potential risk for humans based on the pharmacokinetic properties of each drug. Currently, all new therapy regimens are contraindicated in this setting because of lack of sufficient safety information and adequate measures of contraception are still routinely recommended for female patients of childbearing potential. PMID:27134703

Antiviral therapy for hepatitis C: Has anything changed for pregnant/lactating women?

PubMed

Spera, Anna Maria; Eldin, Tarek Kamal; Tosone, Grazia; Orlando, Raffaele

2016-04-28

Hepatitis C virus (HCV) affects about 3% of the world's population, with the highest prevalence in individuals under 40. The prevalence in pregnant women varies with geographical distribution (highest in developing countries). Prevalence also increases in sub-populations of women at high risk for blood-transmitted infections. HCV infection in pregnancy represents a non-negligible problem. However, most of the past antiviral regimens cannot be routinely offered to pregnant or breastfeeding women because of their side effects. We briefly reviewed the issue of treatment of HCV infection in pregnant/breastfeeding women focusing on the effects of the new direct-acting antivirals on fertility, pregnancy and lactation in animal studies and on the potential risk for humans based on the pharmacokinetic properties of each drug. Currently, all new therapy regimens are contraindicated in this setting because of lack of sufficient safety information and adequate measures of contraception are still routinely recommended for female patients of childbearing potential.

Hydrogen bonds and antiviral activity of benzaldehyde derivatives

NASA Astrophysics Data System (ADS)

Tolstorozhev, G. B.; Skornyakov, I. V.; Belkov, M. V.; Shadyro, O. I.; Brinkevich, S. D.; Samovich, S. N.

2012-09-01

We have obtained the Fourier transform IR spectra of solutions of benzaldehyde derivatives having different antiviral activities against a herpes virus. We observe a correlation between the presence of hydrogen bonds in the benzaldehyde molecules and the appearance of antiviral properties in the compounds. For compounds having antiviral activity, we have obtained spectral data suggesting the existence of hydrogen bonds of the type C=OṡṡṡH-O and O-HṡṡṡO in the molecules. When the hydrogen atom in the hydroxyl groups are replaced by a methyl group, no intramolecular hydrogen bonds are formed and the compounds lose their antiviral activity.

Oral antivirals for the acute treatment of recurrent herpes labialis.

PubMed

Jensen, Lori A; Hoehns, James D; Squires, Cindy L

2004-04-01

To evaluate the use and benefit of oral antivirals in the acute treatment of episodic, recurrent herpes labialis. A literature search was performed in MEDLINE (1966-August 2003) using acyclovir, famciclovir, valacyclovir, cold sores, herpes labialis, and HSV-1 as search terms. We reviewed 5 placebo-controlled and 2 comparative studies evaluating oral antivirals for acute treatment of recurrent herpes labialis. No studies directly compared different antivirals. Studies discussing the efficacy of antivirals for chronic suppression of herpes simplex virus-1 infection were not included. Treatment with oral antivirals decreases the duration of lesion episodes and pain by approximately one day; however, the antivirals do not abort lesions from developing. Clinical implications of these results appear relatively modest.

Multifunctional roles of leader protein of foot-and-mouth disease viruses in suppressing host antiviral responses.

PubMed

Liu, Yingqi; Zhu, Zixiang; Zhang, Miaotao; Zheng, Haixue

2015-10-28

Foot-and-mouth disease virus (FMDV) leader protein (L(pro)) is a papain-like proteinase, which plays an important role in FMDV pathogenesis. L(pro) exists as two forms, Lab and Lb, due to translation being initiated from two different start codons separated by 84 nucleotides. L(pro) self-cleaves from the nascent viral polyprotein precursor as the first mature viral protein. In addition to its role as a viral proteinase, L(pro) also has the ability to antagonize host antiviral effects. To promote FMDV replication, L(pro) can suppress host antiviral responses by three different mechanisms: (1) cleavage of eukaryotic translation initiation factor 4 γ (eIF4G) to shut off host protein synthesis; (2) inhibition of host innate immune responses through restriction of interferon-α/β production; and (3) L(pro) can also act as a deubiquitinase and catalyze deubiquitination of innate immune signaling molecules. In the light of recent functional and biochemical findings regarding L(pro), this review introduces the basic properties of L(pro) and the mechanisms by which it antagonizes host antiviral responses.

Early development of de novo hepatocellular carcinoma after direct-acting agent therapy: Comparison with pegylated interferon-based therapy in chronic hepatitis C patients.

PubMed

Yoo, S H; Kwon, J H; Nam, S W; Kim, H Y; Kim, C W; You, C R; Choi, S W; Cho, S H; Han, J-Y; Song, D S; Chang, U I; Yang, J M; Lee, H L; Lee, S W; Han, N I; Kim, S-H; Song, M J; Hwang, S; Sung, P S; Jang, J W; Bae, S H; Choi, J Y; Yoon, S K

2018-04-16

Patients with chronic hepatitis C who achieve a sustained viral response after pegylated interferon therapy have a reduced risk of hepatocellular carcinoma, but the risk after treatment with direct-acting antivirals is unclear. We compared the rates of early development of hepatocellular carcinoma after direct-acting antivirals and after pegylated interferon therapy. We retrospectively analysed 785 patients with chronic hepatitis C who had no history of hepatocellular carcinoma (211 treated with pegylated interferon, 574 with direct-acting antivirals) and were followed up for at least 24 weeks after antiviral treatment. De novo hepatocellular carcinoma developed in 6 of 574 patients receiving direct-acting antivirals and in 1 of 211 patients receiving pegylated interferon. The cumulative incidence of early hepatocellular carcinoma development did not differ between the treatment groups either for the whole cohort (1.05% vs 0.47%, P = .298) or for those patients with Child-Pugh Class A cirrhosis (3.73% vs 2.94%, P = .827). Multivariate analysis indicated that alpha-fetoprotein level >9.5 ng/mL at the time of end-of-treatment response was the only independent risk factor for early development of hepatocellular carcinoma in all patients (P < .0001, hazard ratio 176.174, 95% confidence interval 10.768-2882.473) and in patients treated with direct-acting agents (P < .0001, hazard ratio 128.402, 95% confidence interval 8.417-1958.680). In conclusion, the rate of early development of hepatocellular carcinoma did not differ between patients treated with pegylated interferon and those treated with direct-acting antivirals and was associated with the serum alpha-fetoprotein level at the time of end-of-treatment response. © 2018 John Wiley & Sons Ltd.

Antiviral Defense Mechanisms in Honey Bees

PubMed Central

Brutscher, Laura M.; Daughenbaugh, Katie F.; Flenniken, Michelle L.

2015-01-01

Honey bees are significant pollinators of agricultural crops and other important plant species. High annual losses of honey bee colonies in North America and in some parts of Europe have profound ecological and economic implications. Colony losses have been attributed to multiple factors including RNA viruses, thus understanding bee antiviral defense mechanisms may result in the development of strategies that mitigate colony losses. Honey bee antiviral defense mechanisms include RNA-interference, pathogen-associated molecular pattern (PAMP) triggered signal transduction cascades, and reactive oxygen species generation. However, the relative importance of these and other pathways is largely uncharacterized. Herein we review the current understanding of honey bee antiviral defense mechanisms and suggest important avenues for future investigation. PMID:26273564

Systems Biology-Based Investigation of Cellular Antiviral Drug Targets Identified by Gene-Trap Insertional Mutagenesis.

PubMed

Cheng, Feixiong; Murray, James L; Zhao, Junfei; Sheng, Jinsong; Zhao, Zhongming; Rubin, Donald H

2016-09-01

Viruses require host cellular factors for successful replication. A comprehensive systems-level investigation of the virus-host interactome is critical for understanding the roles of host factors with the end goal of discovering new druggable antiviral targets. Gene-trap insertional mutagenesis is a high-throughput forward genetics approach to randomly disrupt (trap) host genes and discover host genes that are essential for viral replication, but not for host cell survival. In this study, we used libraries of randomly mutagenized cells to discover cellular genes that are essential for the replication of 10 distinct cytotoxic mammalian viruses, 1 gram-negative bacterium, and 5 toxins. We herein reported 712 candidate cellular genes, characterizing distinct topological network and evolutionary signatures, and occupying central hubs in the human interactome. Cell cycle phase-specific network analysis showed that host cell cycle programs played critical roles during viral replication (e.g. MYC and TAF4 regulating G0/1 phase). Moreover, the viral perturbation of host cellular networks reflected disease etiology in that host genes (e.g. CTCF, RHOA, and CDKN1B) identified were frequently essential and significantly associated with Mendelian and orphan diseases, or somatic mutations in cancer. Computational drug repositioning framework via incorporating drug-gene signatures from the Connectivity Map into the virus-host interactome identified 110 putative druggable antiviral targets and prioritized several existing drugs (e.g. ajmaline) that may be potential for antiviral indication (e.g. anti-Ebola). In summary, this work provides a powerful methodology with a tight integration of gene-trap insertional mutagenesis testing and systems biology to identify new antiviral targets and drugs for the development of broadly acting and targeted clinical antiviral therapeutics.

Activation of cGAS-dependent antiviral responses by DNA intercalating agents.

PubMed

Pépin, Geneviève; Nejad, Charlotte; Thomas, Belinda J; Ferrand, Jonathan; McArthur, Kate; Bardin, Philip G; Williams, Bryan R G; Gantier, Michael P

2017-01-09

Acridine dyes, including proflavine and acriflavine, were commonly used as antiseptics before the advent of penicillins in the mid-1940s. While their mode of action on pathogens was originally attributed to their DNA intercalating activity, work in the early 1970s suggested involvement of the host immune responses, characterized by induction of interferon (IFN)-like activities through an unknown mechanism. We demonstrate here that sub-toxic concentrations of a mixture of acriflavine and proflavine instigate a cyclic-GMP-AMP (cGAMP) synthase (cGAS)-dependent type-I IFN antiviral response. This pertains to the capacity of these compounds to induce low level DNA damage and cytoplasmic DNA leakage, resulting in cGAS-dependent cGAMP-like activity. Critically, acriflavine:proflavine pre-treatment of human primary bronchial epithelial cells significantly reduced rhinovirus infection. Collectively, our findings constitute the first evidence that non-toxic DNA binding agents have the capacity to act as indirect agonists of cGAS, to exert potent antiviral effects in mammalian cells. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Direct anti-HCV agents

PubMed Central

Zhang, Xingquan

2015-01-01

Unlike human immunodeficiency virus (HIV) and hepatitis B virus (HBV), hepatitis C virus (HCV) infection is a curable disease. Current direct antiviral agent (DAA) targets are focused on HCV NS3/4A protein (protease), NS5B protein (polymerase) and NS5A protein. The first generation of DAAs includes boceprevir and telaprevir, which are protease inhibitors and were approved for clinical use in 2011. The cure rate for genotype 1 patients increased from 45% to 70% when boceprevir or telaprevir was added to standard PEG-IFN/ribavirin. More effective and less toxic second generation DAAs supplanted these drugs by 2013. The second generation of DAAs includes sofosbuvir (Sovaldi), simeprevir (Olysio), and fixed combination medicines Harvoni and Viekira Pak. These drugs increase cure rates to over 90% without the need for interferon and effectively treat all HCV genotypes. With these drugs the “cure HCV” goal has become a reality. Concerns remain about drug resistance mutations and the high cost of these drugs. The investigation of new HCV drugs is progressing rapidly; fixed dose combination medicines in phase III clinical trials include Viekirax, asunaprevir+daclatasvir+beclabuvir, grazoprevir+elbasvir and others. PMID:26904396

Drug interactions between buprenorphine, methadone and hepatitis C therapeutics.

PubMed

Ogbuagu, Onyema; Friedland, Gerald; Bruce, R Douglas

2016-07-01

People who inject drugs (PWID) and other individuals with opioid use disorders have a dramatically higher prevalence of hepatitis C virus (HCV) infection than the general population. The availability of novel direct acting antivirals (DAAs) for the treatment of HCV infection with very high efficacy, improved tolerability and shortened treatment durations have led to global efforts to ramp up treatment for all HCV-infected individuals to prevent or delay complications of the disease. Individuals with opioid use disorders, including those on medication-assisted therapy such as methadone or buprenorphine, are a key demographic group that can benefit from HCV treatment given their high HCV prevalence; however, pharmacokinetic and pharmacodynamic drug interactions could blunt their utility. We performed a comprehensive literature review of published and unpublished data from PubMed database, relevant conference abstracts/proceedings and FDA approved drug package inserts, to review the pharmacokinetic (PK) profile and drug interactions between currently approved HCV DAAs and methadone and buprenorphine. The paper highlights specific drug combinations which result in altered opioid drug levels including telaprevir/methadone, daclatasvir/buprenorphine, and Abbvie 3D combination regimen (paritaprevir, ritonavir, ombitasvir and dasabuvir)/buprenorphine. However, concurrent pharmacodynamics assessments did not reveal significant signs and symptoms of opioid withdrawal or toxicity that would preclude concurrent administration.

State of the Art, Unresolved Issues, and Future Research Directions in the Fight against Hepatitis C Virus: Perspectives for Screening, Diagnostics of Resistances, and Immunization

PubMed Central

Ansaldi, Filippo

2016-01-01

Hepatitis C virus (HCV) still represents a major public health threat, with a dramatic burden from both epidemiological and clinical points of view. New generation of direct-acting antiviral agents (DAAs) has been recently introduced in clinical practice promising to cure HCV and to overcome the issues related to the interferon-based therapies. However, the emergence of drug resistance and the suboptimal activity of DAAs therapies against diverse HCV genotypes have been observed, determining treatment failure and hampering an effective control of HCV spread worldwide. Moreover, these treatments remain poorly accessible, particularly in low-income countries. Finally, effective screening strategy is crucial to early identifying and treating all HCV chronically infected patients. For all these reasons, even though new drugs may contribute to impacting HCV spread worldwide a preventive HCV vaccine remains a cornerstone in the road to significantly reduce the HCV spread globally, with the ultimate goal of its eradication. Advances in molecular vaccinology, together with a strong financial, political, and societal support, will enable reaching this fundamental success in the coming years. In this comprehensive review, the state of the art about these major topics in the fight against HCV and the future of research in these fields are discussed. PMID:27843956

Hepatitis C Virus: A Critical Appraisal of New Approaches to Therapy

PubMed Central

Nelson, David R.; Jensen, Donald M.; Sulkowski, Mark S.; Everson, Greg; Fried, Michael W.; Gordon, Stuart C.; Jacobson, Ira; Reau, Nancy S.; Sherman, Kenneth; Terrault, Nora; Thomas, David

2012-01-01

The HCV council 2011 convened 11 leading clinicians and researchers in hepatitis C virus from academic medical centers in the United States to provide a forum for the practical and comprehensive evaluation of current data regarding best practices for integrating new direct-acting antiviral agents into existing treatment paradigms. The council investigated 10 clinical practice statements related to HCV treatment that reflect key topical areas. Faculty members reviewed and discussed the data related to each statement, and voted on the nature of the evidence and their level of support for each statement. In this new era of DAAs, a comprehensive and critical analysis of the literature is needed to equip clinicians with the knowledge necessary to design, monitor, and modify treatment regimens in order to optimize patient outcomes. PMID:23094146

Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn

Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified amore » novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.« less

Efficacy and safety of 3-week response-guided triple direct-acting antiviral therapy for chronic hepatitis C infection: a phase 2, open-label, proof-of-concept study

DOE PAGES

Lau, George; Benhamou, Yves; Chen, Guofeng; ...

2016-07-25

In order to shorten the course of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, we examined the antiviral efficacy and safety of 3 weeks of response-guided therapy with an NS3 protease inhibitor and dual NS5A inhibitor–NS5B nucleotide analogue. In this open-label, phase 2a, single centre study, Chinese patients with chronic HCV genotype 1b infection without cirrhosis were randomly allocated by a computer program to one of three treatment groups (sofosbuvir, ledipasvir, and asunaprevir; sofosbuvir, daclatasvir, and simeprevir; or sofosbuvir, daclatasvir, and asunaprevir) until six patients in each group (1:1:1) achieved an ultrarapid virological response (plasma HCV RNAmore » <500 IU/mL by day 2, measured by COBAS TaqMan HCV test, version 2.0). Patients with an ultrarapid virological response received 3 weeks of therapy. Patients who did not achieve an ultrarapid response were switched to sofosbuvir and ledipasvir for either 8 weeks or 12 weeks. Furthermore, the primary endpoint was the proportion of patients with a sustained virological response at 12 weeks (SVR12) after treatment completion, analysed in the intention-to-treat population. All patients who achieved an ultrarapid virological response were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT02470858. Between April 5, 2015, and April 15, 2015, 26 eligible patients were recruited. 12 patients were assigned to sofosbuvir, ledipasvir, and asunaprevir; six to sofosbuvir, daclatasvir, and simeprevir; and eight to sofosbuvir, daclatasvir, and asunaprevir. Six patients in each group achieved an ultrarapid virological response (18 [69%]). All patients with an ultrarapid virological response who were given 3 weeks of triple therapy achieved SVR12. The most common adverse events were fatigue (one [17%] of six patients receiving sofosbuvir, ledipasvir, and asunaprevir; one [17%] of six patients receiving sofosbuvir, daclatasvir, and

Efficacy and safety of 3-week response-guided triple direct-acting antiviral therapy for chronic hepatitis C infection: a phase 2, open-label, proof-of-concept study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lau, George; Benhamou, Yves; Chen, Guofeng

In order to shorten the course of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, we examined the antiviral efficacy and safety of 3 weeks of response-guided therapy with an NS3 protease inhibitor and dual NS5A inhibitor–NS5B nucleotide analogue. In this open-label, phase 2a, single centre study, Chinese patients with chronic HCV genotype 1b infection without cirrhosis were randomly allocated by a computer program to one of three treatment groups (sofosbuvir, ledipasvir, and asunaprevir; sofosbuvir, daclatasvir, and simeprevir; or sofosbuvir, daclatasvir, and asunaprevir) until six patients in each group (1:1:1) achieved an ultrarapid virological response (plasma HCV RNAmore » <500 IU/mL by day 2, measured by COBAS TaqMan HCV test, version 2.0). Patients with an ultrarapid virological response received 3 weeks of therapy. Patients who did not achieve an ultrarapid response were switched to sofosbuvir and ledipasvir for either 8 weeks or 12 weeks. Furthermore, the primary endpoint was the proportion of patients with a sustained virological response at 12 weeks (SVR12) after treatment completion, analysed in the intention-to-treat population. All patients who achieved an ultrarapid virological response were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT02470858. Between April 5, 2015, and April 15, 2015, 26 eligible patients were recruited. 12 patients were assigned to sofosbuvir, ledipasvir, and asunaprevir; six to sofosbuvir, daclatasvir, and simeprevir; and eight to sofosbuvir, daclatasvir, and asunaprevir. Six patients in each group achieved an ultrarapid virological response (18 [69%]). All patients with an ultrarapid virological response who were given 3 weeks of triple therapy achieved SVR12. The most common adverse events were fatigue (one [17%] of six patients receiving sofosbuvir, ledipasvir, and asunaprevir; one [17%] of six patients receiving sofosbuvir, daclatasvir, and

WITHDRAWN. Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-05-04

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.47 to 1.02, n = 1715). For people with severe Bell's palsy (House-Brackmann scores of 5 and 6 or the equivalent in other scales), we found a reduction in the rate of incomplete recovery at month six when antivirals plus corticosteroids were used (RR 0.64, 95% CI 0.41 to 0

IFNβ/TNFα synergism induces a non-canonical STAT2/IRF9-dependent pathway triggering a novel DUOX2 NADPH Oxidase-mediated airway antiviral response

PubMed Central

Fink, Karin; Martin, Lydie; Mukawera, Esperance; Chartier, Stéfany; De Deken, Xavier; Brochiero, Emmanuelle; Miot, Françoise; Grandvaux, Nathalie

2013-01-01

Airway epithelial cells are key initial innate immune responders in the fight against respiratory viruses, primarily via the secretion of antiviral and proinflammatory cytokines that act in an autocrine/paracrine fashion to trigger the establishment of an antiviral state. It is currently thought that the early antiviral state in airway epithelial cells primarily relies on IFNβ secretion and the subsequent activation of the interferon-stimulated gene factor 3 (ISGF3) transcription factor complex, composed of STAT1, STAT2 and IRF9, which regulates the expression of a panoply of interferon-stimulated genes encoding proteins with antiviral activities. However, the specific pathways engaged by the synergistic action of different cytokines during viral infections, and the resulting physiological outcomes are still ill-defined. Here, we unveil a novel delayed antiviral response in the airways, which is initiated by the synergistic autocrine/paracrine action of IFNβ and TNFα, and signals through a non-canonical STAT2- and IRF9-dependent, but STAT1-independent cascade. This pathway ultimately leads to the late induction of the DUOX2 NADPH oxidase expression. Importantly, our study uncovers that the development of the antiviral state relies on DUOX2-dependent H2O2 production. Key antiviral pathways are often targeted by evasion strategies evolved by various pathogenic viruses. In this regard, the importance of the novel DUOX2-dependent antiviral pathway is further underlined by the observation that the human respiratory syncytial virus is able to subvert DUOX2 induction. PMID:23545780

Antiviral screening of forty-two Egyptian medicinal plants.

PubMed

Soltan, Maha Mohamed; Zaki, Adel Kamal

2009-10-29

Egyptian medicinal plants are well known by their diverse uses in traditional folk medicine to cure various ailments including infectious diseases. Forty-two Egyptian medicinal plant species were selected from local market and were subjected to antiviral screening bioassay to investigate and to evaluate their biological activities. Hydro-alcoholic extracts of each species were separately prepared and tested against three viruses: herpes simplex-1 virus (HSV), poliomyelitis-1 virus (POLIO) and vesicular stomatitis virus (VSV). The antiviral activity were determined by means of the end point titration technique (EPTT) that depends on the ability of plant extract dilutions to inhibit the produced cytopathogenic effect (CPE) and expressed as reduction factor (Rf) of the viral titer. Achillea fragrantissima, Jasonia montana and Globularia arabica are found to have antiviral activity against POLIO in a concentration dependent manner at complete non-toxic concentration range 10-100 microg/ml (Rf 10(6)), 10-100 microg/ml (Rf 10(5)) and 50-100 microg/ml (Rf 10(4)), respectively while Tanacetum sinaicum are found to have moderate antiviral activity against POLIO at concentration of 50-100 microg/ml (Rf 10(2)). Ephedra alata and Moringa peregrina are found to have antiviral activity against HSV (Rf 10(4)). Also, the results revealed that Capparis sinaica, Tamarix nilotica and Cyperus rotundus are found to have virucidal effect against HSV. All the forty-two plant species are found to have no reliable antiviral activity against VSV. The specific indications claimed by the traditional healers are confirmed by antiviral test.

Genetic Diversity and Selective Pressure in Hepatitis C Virus Genotypes 1-6: Significance for Direct-Acting Antiviral Treatment and Drug Resistance.

PubMed

Cuypers, Lize; Li, Guangdi; Libin, Pieter; Piampongsant, Supinya; Vandamme, Anne-Mieke; Theys, Kristof

2015-09-16

Treatment with pan-genotypic direct-acting antivirals, targeting different viral proteins, is the best option for clearing hepatitis C virus (HCV) infection in chronically infected patients. However, the diversity of the HCV genome is a major obstacle for the development of antiviral drugs, vaccines, and genotyping assays. In this large-scale analysis, genome-wide diversity and selective pressure was mapped, focusing on positions important for treatment, drug resistance, and resistance testing. A dataset of 1415 full-genome sequences, including genotypes 1-6 from the Los Alamos database, was analyzed. In 44% of all full-genome positions, the consensus amino acid was different for at least one genotype. Focusing on positions sharing the same consensus amino acid in all genotypes revealed that only 15% was defined as pan-genotypic highly conserved (≥99% amino acid identity) and an additional 24% as pan-genotypic conserved (≥95%). Despite its large genetic diversity, across all genotypes, codon positions were rarely identified to be positively selected (0.23%-0.46%) and predominantly found to be under negative selective pressure, suggesting mainly neutral evolution. For NS3, NS5A, and NS5B, respectively, 40% (6/15), 33% (3/9), and 14% (2/14) of the resistance-related positions harbored as consensus the amino acid variant related to resistance, potentially impeding treatment. For example, the NS3 variant 80K, conferring resistance to simeprevir used for treatment of HCV1 infected patients, was present in 39.3% of the HCV1a strains and 0.25% of HCV1b strains. Both NS5A variants 28M and 30S, known to be associated with resistance to the pan-genotypic drug daclatasvir, were found in a significant proportion of HCV4 strains (10.7%). NS5B variant 556G, known to confer resistance to non-nucleoside inhibitor dasabuvir, was observed in 8.4% of the HCV1b strains. Given the large HCV genetic diversity, sequencing efforts for resistance testing purposes may need to be

Antiviral therapy: current concepts and practices.

PubMed Central

Bean, B

1992-01-01

Drugs capable of inhibiting viruses in vitro were described in the 1950s, but real progress was not made until the 1970s, when agents capable of inhibiting virus-specific enzymes were first identified. The last decade has seen rapid progress in both our understanding of antiviral therapy and the number of antiviral agents on the market. Amantadine and ribavirin are available for treatment of viral respiratory infections. Vidarabine, acyclovir, ganciclovir, and foscarnet are used for systemic treatment of herpesvirus infections, while ophthalmic preparations of idoxuridine, trifluorothymidine, and vidarabine are available for herpes keratitis. For treatment of human immunodeficiency virus infections, zidovudine and didanosine are used. Immunomodulators, such as interferons and colony-stimulating factors, and immunoglobulins are being used increasingly for viral illnesses. While resistance to antiviral drugs has been seen, especially among AIDS patients, it has not become widespread and is being intensely studied. Increasingly, combinations of agents are being used: to achieve synergistic inhibition of viruses, to delay or prevent resistance, and to decrease dosages of toxic drugs. New approaches, such as liposomes carrying antiviral drugs and computer-aided drug design, are exciting and promising prospects for the future. PMID:1576586

RIG-I Like Receptors and Their Signaling Crosstalk in the Regulation of Antiviral Immunity

PubMed Central

Ramos, Hilario J; Gale, Michael

2011-01-01

During virus infection, multiple immune signaling pathways are triggered, both within the host cell and bystander cells of an infected tissue. These pathways act in concert to mediate innate antiviral immunity and to initiate the inflammatory response against infection. The RIG-I-like receptor (RLR) family of pattern recognition receptors (PRRs) is a group of cytosolic RNA helicase proteins that can identify viral RNA as nonself via binding to pathogen associated molecular patter (PAMP) motifs within RNA ligands that accumulate during virus infection. This interaction then leads to triggering of an innate antiviral response within the infected cells through RLR induction of downstream effector molecules such as type I interferon (IFN) and other pro-inflammatory cytokines that serve to induce antiviral and inflammatory gene expression within the local tissue. Cellular regulation of RLR signaling is a critical process that can direct the outcome of infection and is essential for governance of the overall immune response and avoidance of immune toxicity. Mechanisms of positive and negative regulation of RLR signaling have been identified that include signaling crosstalk between RLR pathways and Nuclear Oligomerization Domain (NOD)-Like Receptor (NLR) pathways and Caspase networks. Furthermore, many viruses have evolved mechanisms to target these pathways to promote enhanced replication and spread within the host. These virus-host interactions therefore carry important consequences for host immunity and viral pathogenesis. Understanding the pivotal role of RLRs in immune regulation and signaling crosstalk in antiviral immunity may provide new insights into therapeutic strategies for the control of virus infection and immunity. PMID:21949557

Targeting Innate Immunity for Antiviral Therapy through Small Molecule Agonists of the RLR Pathway

PubMed Central

Pattabhi, Sowmya; Wilkins, Courtney R.; Dong, Ran; Knoll, Megan L.; Posakony, Jeffrey; Kaiser, Shari; Mire, Chad E.; Wang, Myra L.; Ireton, Renee C.; Geisbert, Thomas W.; Bedard, Kristin M.; Iadonato, Shawn P.

2015-01-01

ABSTRACT The cellular response to virus infection is initiated when pathogen recognition receptors (PRR) engage viral pathogen-associated molecular patterns (PAMPs). This process results in induction of downstream signaling pathways that activate the transcription factor interferon regulatory factor 3 (IRF3). IRF3 plays a critical role in antiviral immunity to drive the expression of innate immune response genes, including those encoding antiviral factors, type 1 interferon, and immune modulatory cytokines, that act in concert to restrict virus replication. Thus, small molecule agonists that can promote IRF3 activation and induce innate immune gene expression could serve as antivirals to induce tissue-wide innate immunity for effective control of virus infection. We identified small molecule compounds that activate IRF3 to differentially induce discrete subsets of antiviral genes. We tested a lead compound and derivatives for the ability to suppress infections caused by a broad range of RNA viruses. Compound administration significantly decreased the viral RNA load in cultured cells that were infected with viruses of the family Flaviviridae, including West Nile virus, dengue virus, and hepatitis C virus, as well as viruses of the families Filoviridae (Ebola virus), Orthomyxoviridae (influenza A virus), Arenaviridae (Lassa virus), and Paramyxoviridae (respiratory syncytial virus, Nipah virus) to suppress infectious virus production. Knockdown studies mapped this response to the RIG-I-like receptor pathway. This work identifies a novel class of host-directed immune modulatory molecules that activate IRF3 to promote host antiviral responses to broadly suppress infections caused by RNA viruses of distinct genera. IMPORTANCE Incidences of emerging and reemerging RNA viruses highlight a desperate need for broad-spectrum antiviral agents that can effectively control infections caused by viruses of distinct genera. We identified small molecule compounds that can

Decision making with regard to antiviral intervention during an influenza pandemic.

PubMed

Shim, Eunha; Chapman, Gretchen B; Galvani, Alison P

2010-01-01

Antiviral coverage is defined by the proportion of the population that takes antiviral prophylaxis or treatment. High coverage of an antiviral drug has epidemiological and evolutionary repercussions. Antivirals select for drug resistance within the population, and individuals may experience adverse effects. To determine optimal antiviral coverage in the context of an influenza outbreak, we compared 2 perspectives: 1) the individual level (the Nash perspective), and 2) the population level (utilitarian perspective). We developed an epidemiological game-theoretic model of an influenza pandemic. The data sources were published literature and a national survey. The target population was the US population. The time horizon was 6 months. The perspective was individuals and the population overall. The interventions were antiviral prophylaxis and treatment. The outcome measures were the optimal coverage of antivirals in an influenza pandemic. At current antiviral pricing, the optimal Nash strategy is 0% coverage for prophylaxis and 30% coverage for treatment, whereas the optimal utilitarian strategy is 19% coverage for prophylaxis and 100% coverage for treatment. Subsidizing prophylaxis by $440 and treatment by $85 would bring the Nash and utilitarian strategies into alignment. For both prophylaxis and treatment, the optimal antiviral coverage decreases as pricing of antivirals increases. Our study does not incorporate the possibility of an effective vaccine and lacks probabilistic sensitivity analysis. Our survey also does not completely represent the US population. Because our model assumes a homogeneous population and homogeneous antiviral pricing, it does not incorporate heterogeneity of preference. The optimal antiviral coverage from the population perspective and individual perspectives differs widely for both prophylaxis and treatment strategies. Optimal population and individual strategies for prophylaxis and treatment might be aligned through subsidization.

Bugs Are Not to Be Silenced: Small RNA Pathways and Antiviral Responses in Insects.

PubMed

Mongelli, Vanesa; Saleh, Maria-Carla

2016-09-29

Like every other organism on Earth, insects are infected with viruses, and they rely on RNA interference (RNAi) mechanisms to circumvent viral infections. A remarkable characteristic of RNAi is that it is both broadly acting, because it is triggered by double-stranded RNA molecules derived from virtually any virus, and extremely specific, because it targets only the particular viral sequence that initiated the process. Reviews covering the different facets of the RNAi antiviral immune response in insects have been published elsewhere. In this review, we build a framework to guide future investigation. We focus on the remaining questions and avenues of research that need to be addressed to move the field forward, including issues such as the activity of viral suppressors of RNAi, comparative genomics, the development of detailed maps of the subcellular localization of viral replication complexes with the RNAi machinery, and the regulation of the antiviral RNAi response.

Nucleic acid polymers: Broad spectrum antiviral activity, antiviral mechanisms and optimization for the treatment of hepatitis B and hepatitis D infection.

PubMed

Vaillant, Andrew

2016-09-01

Antiviral polymers are a well-studied class of broad spectrum viral attachment/entry inhibitors whose activity increases with polymer length and with increased amphipathic (hydrophobic) character. The newest members of this class of compounds are nucleic acid polymers whose activity is derived from the sequence independent properties of phosphorothioated oligonucleotides as amphipathic polymers. Although the antiviral mechanisms and broad spectrum antiviral activity of nucleic acid polymers mirror the functionality of other members of this class, they exert in addition a unique post entry activity in hepatitis B infection which inhibits the release of HBsAg from infected hepatocytes. This review provides a general overview of the antiviral polymer class with a focus on nucleic acid polymers and their development as therapeutic agents for the treatment of hepatitis B/hepatitis D. This article forms part of a symposium in Antiviral Research on ''An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B.''. Copyright © 2016 The Author. Published by Elsevier B.V. All rights reserved.

Modeling cost-effectiveness and health gains of a "universal" versus "prioritized" hepatitis C virus treatment policy in a real-life cohort.

PubMed

Kondili, Loreta A; Romano, Federica; Rolli, Francesca Romana; Ruggeri, Matteo; Rosato, Stefano; Brunetto, Maurizia Rossana; Zignego, Anna Linda; Ciancio, Alessia; Di Leo, Alfredo; Raimondo, Giovanni; Ferrari, Carlo; Taliani, Gloria; Borgia, Guglielmo; Santantonio, Teresa Antonia; Blanc, Pierluigi; Gaeta, Giovanni Battista; Gasbarrini, Antonio; Chessa, Luchino; Erne, Elke Maria; Villa, Erica; Ieluzzi, Donatella; Russo, Francesco Paolo; Andreone, Pietro; Vinci, Maria; Coppola, Carmine; Chemello, Liliana; Madonia, Salvatore; Verucchi, Gabriella; Persico, Marcello; Zuin, Massimo; Puoti, Massimo; Alberti, Alfredo; Nardone, Gerardo; Massari, Marco; Montalto, Giuseppe; Foti, Giuseppe; Rumi, Maria Grazia; Quaranta, Maria Giovanna; Cicchetti, Americo; Craxì, Antonio; Vella, Stefano

2017-12-01

We evaluated the cost-effectiveness of two alternative direct-acting antiviral (DAA) treatment policies in a real-life cohort of hepatitis C virus-infected patients: policy 1, "universal," treat all patients, regardless of fibrosis stage; policy 2, treat only "prioritized" patients, delay treatment of the remaining patients until reaching stage F3. A liver disease progression Markov model, which used a lifetime horizon and health care system perspective, was applied to the PITER cohort (representative of Italian hepatitis C virus-infected patients in care). Specifically, 8,125 patients naive to DAA treatment, without clinical, sociodemographic, or insurance restrictions, were used to evaluate the policies' cost-effectiveness. The patients' age and fibrosis stage, assumed DAA treatment cost of €15,000/patient, and the Italian liver disease costs were used to evaluate quality-adjusted life-years (QALY) and incremental cost-effectiveness ratios (ICER) of policy 1 versus policy 2. To generalize the results, a European scenario analysis was performed, resampling the study population, using the mean European country-specific health states costs and mean treatment cost of €30,000. For the Italian base-case analysis, the cost-effective ICER obtained using policy 1 was €8,775/QALY. ICERs remained cost-effective in 94%-97% of the 10,000 probabilistic simulations. For the European treatment scenario the ICER obtained using policy 1 was €19,541.75/QALY. ICER was sensitive to variations in DAA costs, in the utility value of patients in fibrosis stages F0-F3 post-sustained virological response, and in the transition probabilities from F0 to F3. The ICERs decrease with decreasing DAA prices, becoming cost-saving for the base price (€15,000) discounts of at least 75% applied in patients with F0-F2 fibrosis. Extending hepatitis C virus treatment to patients in any fibrosis stage improves health outcomes and is cost-effective; cost-effectiveness significantly increases

Decision Making with Regard to Antiviral Intervention during an Influenza Pandemic

PubMed Central

Shim, Eunha; Chapman, Gretchen B.; Galvani, Alison P.

2012-01-01

Background Antiviral coverage is defined by the proportion of the population that takes antiviral prophylaxis or treatment. High coverage of an antiviral drug has epidemiological and evolutionary repercussions. Antivirals select for drug resistance within the population, and individuals may experience adverse effects. To determine optimal antiviral coverage in the context of an influenza outbreak, we compared 2 perspectives: 1) the individual level (the Nash perspective), and 2) the population level (utilitarian perspective). Methods We developed an epidemiological game-theoretic model of an influenza pandemic. The data sources were published literature and a national survey. The target population was the US population. The time horizon was 6 months. The perspective was individuals and the population overall. The interventions were antiviral prophylaxis and treatment. The outcome measures were the optimal coverage of antivirals in an influenza pandemic. Results At current antiviral pricing, the optimal Nash strategy is 0% coverage for prophylaxis and 30% coverage for treatment, whereas the optimal utilitarian strategy is 19% coverage for prophylaxis and 100% coverage for treatment. Subsidizing prophylaxis by $440 and treatment by $85 would bring the Nash and utilitarian strategies into alignment. For both prophylaxis and treatment, the optimal antiviral coverage decreases as pricing of antivirals increases. Our study does not incorporate the possibility of an effective vaccine and lacks probabilistic sensitivity analysis. Our survey also does not completely represent the US population. Because our model assumes a homogeneous population and homogeneous antiviral pricing, it does not incorporate heterogeneity of preference. Conclusions The optimal antiviral coverage from the population perspective and individual perspectives differs widely for both prophylaxis and treatment strategies. Optimal population and individual strategies for prophylaxis and treatment might

Healthcare system cost evaluation of antiviral stockpiling for pandemic influenza preparedness.

PubMed

Li, Yang; Hsu, Edbert B; Links, Jonathan M

2010-06-01

Healthcare workers need to be protected during a severe influenza outbreak; therefore, we evaluated 4 different antiviral strategies: (1) using antiviral medication for outbreak prophylaxis of all hospital employees; (2) using antiviral medication for postexposure prophylaxis (PEP) or treatment of all hospital employees; (3) using a combination of antiviral medication for outbreak prophylaxis of high-risk clinical staff and postexposure prophylaxis or treatment for all other staff; and (4) using antiviral medication for postexposure prophylaxis or treatment of high-risk clinical staff only. Three different purchasing options were applied to each of the 4 antiviral strategies: (1) just-in-time purchase during a severe influenza outbreak, (2) prepandemic stockpiling, or (3) stockpiling through contracts with pharmaceutical manufacturers to reserve a predetermined antiviral supply. Although outbreak prophylaxis of all hospital employees would offer the maximum protection, the large costs associated with such a purchase make this option unrealistic and impractical. In addition, even though postexposure prophylaxis or treatment of only high-risk clinical staff would incur the least expense, the assumed level of protection if these options were offered only to high-risk clinical staff may not be sufficient to maintain routine hospital operations, since needed non-high-risk staff would not be protected. Considering the potential benefits and drawbacks of stockpiling antiviral medication from a cost perspective, it does not appear feasible for hospitals to stockpile antiviral medication in large quantities prior to a severe influenza outbreak. This article focuses on the financial viability of stockpiling antiviral medication, but the potential impact of other factors on the decision to stockpile was also considered and will be explored in future analyses. While legal hurdles related to prescribing, storing, and dispensing antiviral medication can be addressed

18th International Conference on Antiviral Research.

PubMed

Mitchell, William M

2005-08-01

The 18th International Conference on Antiviral Research (ICAR) was held at the Princess Sofia Hotel in Barcelona, Spain, from 11th-14th April, 2005. This is a yearly international meeting sponsored by the International Society for Antiviral Research (ISAR). The current president of ISAR is John A Secrest 3rd of the Southern Research Institute. The scientific programme committee was chaired by John C Drach from the University of Michigan. ISAR was founded in 1987 to exchange prepublication basic, applied and clinical information on the development of antiviral, chemical and biological agents as well as to promote collaborative research. The ISAR has had a major role in the significant advances of the past decade in the reduction of the societal burdens of viral diseases by the focus of ICAR on the discovery and clinical application of antiviral agents. The 18th ICAR was organised as a series of focus presentations on specific viral groups consisting of oral and poster presentations of original research findings. In addition, the conference included plenary speakers, award presentations, a minisymposium on bioterrorism, and a satellite symposium on clinical antiviral drug developments. The size of the conference (> 50 oral and 250 poster presentations) necessitates limitation to the most noteworthy in the judgment of this reviewer. The current membership of the ISAR is approximately 700 with approximately 50% the membership in attendance.

Exploration of (hetero)aryl derived thienylchalcones for antiviral and anticancer activities.

PubMed

Patil, Vikrant; Patil, Siddappa A; Patil, Renukadevi; Bugarin, Alejandro; Beaman, Kenneth; Patil, Shivaputra A

2018-05-23

Search for new antiviral and anticancer agents are essential because of the emergence of drug resistance in recent years. In continuation of our efforts in identifying the new small molecule antiviral and anticancer agents, we identified chalcones as potent antiviral and anticancer agents. With the aim of identifying the broad acting antiviral and anticancer agents, we discovered substituted aryl/heteroaryl derived thienyl chalcones as antiviral and anticancer agents. A focused set of thienyl chalcone derivaties II-VI was screened for selected viruses Hepatitis B virus (HBV), Herpes simplex virus 1 (HSV-1), Human cytomegalovirus (HCMV), Dengue virus 2 (DENV2), Influenza A (H1N1) virus, MERS coronavirus, Poliovirus 1 (PV 1), Rift Valley fever (RVF), Tacaribe virus (TCRV), Venezuelan equine encephalitis virus (VEE) and Zika virus (ZIKV) using the National Institute of Allergy and Infectious Diseases (NIAID)'s Division of Microbiology and Infectious Diseases (DMID) antiviral screening program. Additionally, a cyclopropylquinoline derivative IV has been screened for 60 human cancer cell lines using the Development Therapeutics Program (DTP) of NCI. All thienyl chalcone derivatives II-VI displayed moderate to excellent antiviral activity towards several viruses tested. Compounds V and VI were turned out be active compounds towards human cytomegalovirus for both normal strain (AD169) as well as resistant isolate (GDGr K17). Particularly, cyano derivative V showed very high potency (EC50: <0.05 µM) towards AD169 strain of HCMV compared to standard drug Ganciclovir (EC50: 0.12 µM). Additionally, it showed moderate activity in the secondary assay (AD169; EC50: 2.30 µM). The cyclopropylquinoline derivative IV displayed high potency towards Rift Valley fever virus (RVFV) and Tacaribe virus (TCRV). The cyclopropylquinoline derivative IV is nearly 28 times more potent in our initial in vitro visual assay (EC50: 0.39 μg/ml) and nearly 17 times more potent in neutral red

GPATCH3 negatively regulates RLR-mediated innate antiviral responses by disrupting the assembly of VISA signalosome.

PubMed

Nie, Ying; Ran, Yong; Zhang, Hong-Yan; Huang, Zhe-Fu; Pan, Zhao-Yi; Wang, Su-Yun; Wang, Yan-Yi

2017-04-01

Upon viral infection, retinoic acid-inducible gene I-like receptors (RLRs) recognize viral RNA and trigger a series of signaling events, leading to the induction of type I interferons (IFNs). These processes are delicately regulated to prevent excessive and harmful immune responses. In this study, we identified G patch domain-containing protein 3 (GPATCH3) as a negative regulator of RLR-mediated antiviral signaling pathways. Overexpression of GPATCH3 impaired RNA virus- triggered induction of downstream antiviral genes, whereas its knockdown had opposite effects and attenuated viral replication. In addition, GPATCH3-deficient cells had higher IFNB1 mRNA level compared with control cells after RNA virus infection. Mechanistically, GPATCH3 was recruited to VISA in a viral infection dependent manner and the assembly of VISA/TRAF6/TBK1 signalosome was impaired in GPATCH3-overexpressing cells. In contrast, upon viral infection, the recruitment of TRAF6 and TBK1 to VISA was enhanced in GPATCH3 deficient cells. Taking together, our findings demonstrate that GPATCH3 interacts with VISA and disrupts the assembly of virus-induced VISA signalosome therefore acts as a negative regulator of RLR-mediated innate antiviral immune responses.

GPATCH3 negatively regulates RLR-mediated innate antiviral responses by disrupting the assembly of VISA signalosome

PubMed Central

Nie, Ying; Ran, Yong; Zhang, Hong-Yan; Huang, Zhe-Fu; Wang, Su-Yun

2017-01-01

Upon viral infection, retinoic acid–inducible gene I–like receptors (RLRs) recognize viral RNA and trigger a series of signaling events, leading to the induction of type I interferons (IFNs). These processes are delicately regulated to prevent excessive and harmful immune responses. In this study, we identified G patch domain-containing protein 3 (GPATCH3) as a negative regulator of RLR-mediated antiviral signaling pathways. Overexpression of GPATCH3 impaired RNA virus- triggered induction of downstream antiviral genes, whereas its knockdown had opposite effects and attenuated viral replication. In addition, GPATCH3-deficient cells had higher IFNB1 mRNA level compared with control cells after RNA virus infection. Mechanistically, GPATCH3 was recruited to VISA in a viral infection dependent manner and the assembly of VISA/TRAF6/TBK1 signalosome was impaired in GPATCH3-overexpressing cells. In contrast, upon viral infection, the recruitment of TRAF6 and TBK1 to VISA was enhanced in GPATCH3 deficient cells. Taking together, our findings demonstrate that GPATCH3 interacts with VISA and disrupts the assembly of virus-induced VISA signalosome therefore acts as a negative regulator of RLR-mediated innate antiviral immune responses. PMID:28414768

Structure-Activity Relationships of Acyclic Selenopurine Nucleosides as Antiviral Agents.

PubMed

Sahu, Pramod K; Umme, Tamima; Yu, Jinha; Kim, Gyudong; Qu, Shuhao; Naik, Siddhi D; Jeong, Lak Shin

2017-07-12

A series of acyclic selenopurine nucleosides 3a - f and 4a - g were synthesized based on the bioisosteric rationale between oxygen and selenium, and then evaluated for antiviral activity. Among the compounds tested, seleno-acyclovir ( 4a ) exhibited the most potent anti-herpes simplex virus (HSV)-1 (EC 50 = 1.47 µM) and HSV-2 (EC 50 = 6.34 µM) activities without cytotoxicity up to 100 µM, while 2,6-diaminopurine derivatives 4e - g exhibited significant anti-human cytomegalovirus (HCMV) activity, which is slightly more potent than the guanine derivative 4d , indicating that they might act as prodrugs of seleno-ganciclovir ( 4d ).

The Race To Find Antivirals for Zika Virus

PubMed Central

2017-01-01

ABSTRACT Zika virus (ZIKV), a flavivirus transmitted by mosquitoes, was an almost neglected pathogen until its introduction in the Americas in 2015 and its subsequent explosive spread throughout the continent, where it has infected millions of people. The virus has caused social and sanitary alarm, mainly due to its association with severe neurological disorders (Guillain-Barré syndrome and microcephaly in fetuses and newborns). Nowadays, no specific antiviral therapy against ZIKV is available. However, during the past months, a great effort has been made to search for antiviral candidates using different approaches and methodologies, ranging from testing specific compounds with known antiviral activity to the screening of libraries with hundreds of bioactive molecules. The identified antiviral candidates include drugs targeting viral components as well as cellular ones. Here, an updated review of what has been done in this line is presented. PMID:28348160

Peptidomimetic Escape Mechanisms Arise via Genetic Diversity in the Ligand-Binding Site of the Hepatitis C Virus NS3/4A Serine Protease

PubMed Central

Welsch, Christoph; Shimakami, Tetsuro; Hartmann, Christoph; Yang, Yan; Domingues, Francisco S.; Lengauer, Thomas; Zeuzem, Stefan; Lemon, Stanley M.

2011-01-01

Background & Aims It is a challenge to develop direct-acting antiviral agents (DAAs) that target the NS3/4A protease of hepatitis C virus (HCV) because resistant variants develop. Ketoamide compounds, designed to mimic the natural protease substrate, have been developed as inhibitors. However, clinical trials have revealed rapid selection of resistant mutants, most of which are considered to be pre-existing variants. Methods We identified residues near the ketoamide-binding site in X-ray structures of the genotype 1a protease, co-crystallized with boceprevir or a telaprevir-like ligand, and then identified variants at these positions in 219 genotype 1 sequences from a public database. We used side-chain modeling to assess the potential effects of these variants on the interaction between ketoamide and the protease, and compared these results with the phenotypic effects on ketoamide resistance, RNA replication capacity, and infectious virus yields in a cell culture model of infection. Results Thirteen natural binding-site variants with potential for ketoamide resistance were identified at 10 residues in the protease, near the ketoamide binding site. Rotamer analysis of amino acid side-chain conformations indicated that 2 variants (R155K and D168G) could affect binding of telaprevir more than boceprevir. Measurements of antiviral susceptibility in cell culture studies were consistent with this observation. Four variants (Q41H, I132V, R155K, and D168G) caused low-to-moderate levels of ketoamide resistance; 3 of these were highly fit (Q41H, I132V, and R155K). Conclusions Using a comprehensive sequence and structure-based analysis, we showed how natural variation in the HCV protease NS3/4A sequences might affect susceptibility to first-generation DAAs. These findings increase our understanding of the molecular basis of ketoamide resistance among naturally existing viral variants. PMID:22155364

HCV treatment rates and sustained viral response among people who inject drugs in seven UK sites: real world results and modelling of treatment impact.

PubMed

Martin, N K; Foster, G R; Vilar, J; Ryder, S; Cramp, M E; Gordon, F; Dillon, J F; Craine, N; Busse, H; Clements, A; Hutchinson, S J; Ustianowski, A; Ramsay, M; Goldberg, D J; Irving, W; Hope, V; De Angelis, D; Lyons, M; Vickerman, P; Hickman, M

2015-04-01

Hepatitis C virus (HCV) antiviral treatment for people who inject drugs (PWID) could prevent onwards transmission and reduce chronic prevalence. We assessed current PWID treatment rates in seven UK settings and projected the potential impact of current and scaled-up treatment on HCV chronic prevalence. Data on number of PWID treated and sustained viral response rates (SVR) were collected from seven UK settings: Bristol (37-48% HCV chronic prevalence among PWID), East London (37-48%), Manchester (48-56%), Nottingham (37-44%), Plymouth (30-37%), Dundee (20-27%) and North Wales (27-33%). A model of HCV transmission among PWID projected the 10-year impact of (i) current treatment rates and SVR (ii) scale-up with interferon-free direct acting antivirals (IFN-free DAAs) with 90% SVR. Treatment rates varied from <5 to over 25 per 1000 PWID. Pooled intention-to-treat SVR for PWID were 45% genotypes 1/4 [95%CI 33-57%] and 61% genotypes 2/3 [95%CI 47-76%]. Projections of chronic HCV prevalence among PWID after 10 years of current levels of treatment overlapped substantially with current HCV prevalence estimates. Scaling-up treatment to 26/1000 PWID annually (achieved already in two sites) with IFN-free DAAs could achieve an observable absolute reduction in HCV chronic prevalence of at least 15% among PWID in all sites and greater than a halving in chronic HCV in Plymouth, Dundee and North Wales within a decade. Current treatment rates among PWID are unlikely to achieve observable reductions in HCV chronic prevalence over the next 10 years. Achievable scale-up, however, could lead to substantial reductions in HCV chronic prevalence. © 2014 The Authors Journal of Viral Hepatitis Published by John Wiley & Sons Ltd.

HCV treatment rates and sustained viral response among people who inject drugs in seven UK sites: real world results and modelling of treatment impact

PubMed Central

Martin, N K; Foster, G R; Vilar, J; Ryder, S; E Cramp, M; Gordon, F; Dillon, J F; Craine, N; Busse, H; Clements, A; Hutchinson, S J; Ustianowski, A; Ramsay, M; Goldberg, D J; Irving, W; Hope, V; De Angelis, D; Lyons, M; Vickerman, P; Hickman, M

2015-01-01

Hepatitis C virus (HCV) antiviral treatment for people who inject drugs (PWID) could prevent onwards transmission and reduce chronic prevalence. We assessed current PWID treatment rates in seven UK settings and projected the potential impact of current and scaled-up treatment on HCV chronic prevalence. Data on number of PWID treated and sustained viral response rates (SVR) were collected from seven UK settings: Bristol (37–48% HCV chronic prevalence among PWID), East London (37–48%), Manchester (48–56%), Nottingham (37–44%), Plymouth (30–37%), Dundee (20–27%) and North Wales (27–33%). A model of HCV transmission among PWID projected the 10-year impact of (i) current treatment rates and SVR (ii) scale-up with interferon-free direct acting antivirals (IFN-free DAAs) with 90% SVR. Treatment rates varied from <5 to over 25 per 1000 PWID. Pooled intention-to-treat SVR for PWID were 45% genotypes 1/4 [95%CI 33–57%] and 61% genotypes 2/3 [95%CI 47–76%]. Projections of chronic HCV prevalence among PWID after 10 years of current levels of treatment overlapped substantially with current HCV prevalence estimates. Scaling-up treatment to 26/1000 PWID annually (achieved already in two sites) with IFN-free DAAs could achieve an observable absolute reduction in HCV chronic prevalence of at least 15% among PWID in all sites and greater than a halving in chronic HCV in Plymouth, Dundee and North Wales within a decade. Current treatment rates among PWID are unlikely to achieve observable reductions in HCV chronic prevalence over the next 10 years. Achievable scale-up, however, could lead to substantial reductions in HCV chronic prevalence. PMID:25288193

Antiviral Activity of Polyacrylic and Polymethacrylic Acids

PubMed Central

De Somer, P.; De Clercq, E.; Billiau, A.; Schonne, E.; Claesen, M.

1968-01-01

Polyacrylic acid (PAA) and polymethacrylic acid (PMAA) were investigated for their antiviral properties in tissue culture. Compared to other related polyanions, as dextran sulfate, polystyrene sulfonate, polyvinyl sulfate, and polyphloroglucinol phosphate, PAA and PMAA were found to be significantly more antivirally active and less cytotoxic. PMAA added 24 hr prior to virus inoculation inhibited viral growth most efficiently but it was still effective when added 3 hr after infection. Neither a direct irreversible action on the virus nor inhibition of virus penetration into the cell could explain the antiviral activity of PMAA. PMAA inhibited the adsorption of the virus to the host cell and suppressed the one-cycle viral synthesis in tissue cultures inoculated with infectious RNA. PMID:4302187

Antiviral Innate Immunity through the lens of Systems Biology

PubMed Central

Tripathi, Shashank; García-Sastre, Adolfo

2015-01-01

Cellular innate immunity poses the first hurdle against invading viruses in their attempt to establish infection. This antiviral response is manifested with the detection of viral components by the host cell, followed by transduction of antiviral signals, transcription and translation of antiviral effectors and leads to the establishment of an antiviral state. These events occur in a rather branched and interconnected sequence than a linear path. Traditionally, these processes were studied in the context of a single virus and a host component. However, with the advent of rapid and affordable OMICS technologies it has become feasible to address such questions on a global scale. In the discipline of Systems Biology’, extensive omics datasets are assimilated using computational tools and mathematical models to acquire deeper understanding of complex biological processes. In this review we have catalogued and discussed the application of Systems Biology approaches in dissecting the antiviral innate immune responses. PMID:26657882

Urgency to treat patients with chronic hepatitis C in Asia.

PubMed

Kao, Jia-Horng; Ahn, Sang Hoon; Chien, Rong-Nan; Cho, Mong; Chuang, Wan-Long; Jeong, Sook-Hyang; Liu, Chen-Hua; Paik, Seung-Woon

2017-05-01

Chronic hepatitis C (CHC) infection poses a global healthcare burden, being associated with serious complications if untreated. The prevalence of hepatitis C virus (HCV) infection is highest in areas of Central, South, and East Asia; over 50% of HCV patients worldwide live in the region, where HCV genotypes 1b, 2, 3, and 6 are the most prevalent. Treatment outcomes for chronic hepatitis C vary by ethnicity, and Asian patients achieve higher sustained virologic response rates following interferon (IFN)-based therapy than non-Asians. However, low efficacy, poor safety profile, and subcutaneous administration limit the use of IFN-based therapies. Superior virologic outcomes have been observed with different classes of direct-acting antivirals (DAAs) alone or in combination, and several all-oral DAA regimens are available in Asia. These regimens have shown excellent efficacy and favorable tolerability in clinical trials, yet there is a need for further studies of DAAs in a real world context, particularly in Asia. Furthermore, IFN-free treatment may not be accessible for many patients in the region, and IFN-based regimens remain an option in some countries. There is a need to improve current clinical practices for HCV management in Asia, including effective screening, disease awareness, and prevention programs, and to further understand the cost-effectiveness of IFN-free regimens. The evolution of potent treatments makes HCV eradication a possibility that should be available to all patients. However, access to these therapies in Asian countries has been slow, primarily because of economic barriers that continue to present a hurdle to optimal treatment. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

"Hep C, where art thou": What are the remaining (fundable) questions in hepatitis C virus research?

PubMed

Rosen, Hugo Ramón

2017-01-01

Hepatitis C virus (HCV) has dominated the field of hepatology for the past 25 years, and its cure in the majority of treated patients is one of the greatest achievements in all of medicine. However, the latter has led to the belief by some that HCV research should be shelved for other, more pressing areas. The mission for HCV eradication is far from accomplished. As a historical reference, we should consider that disease elimination has required vaccination with all previously controlled infections including smallpox and polio and that simple, effective treatment is not sufficient in most infections to lead to substantial control. Syphilis is the best example, for which a single dose of penicillin (which literally costs pennies and that we have had since 1945) is curative in early stages. Not only have we not eradicated syphilis, rates of infection have increased in many places within the United States in recent years. Most HCV-infected subjects are unaware of their infection, remaining at risk for transmission to others and disease progression, including cirrhosis and hepatocellular carcinoma. In the era of highly effective direct-acting antivirals (DAAs), many questions pertaining to HCV remain, but they are more complex and difficult to answer. Here, I provide my perspective on some of these salient issues: the residual risk for disease progression after sustained virologic response, the optimal approach to current DAA failures, the impact of targeting people who inject drugs with DAAs, vaccine prospects, and application of neutralizing HCV glycoprotein antibodies. (Hepatology 2017;65:341-349). © 2016 by the American Association for the Study of Liver Diseases.

Declining Hepatitis C Virus (HCV) Incidence in Dutch Human Immunodeficiency Virus-Positive Men Who Have Sex With Men After Unrestricted Access to HCV Therapy.

PubMed

Boerekamps, Anne; van den Berk, Guido E; Lauw, Fanny N; Leyten, Eliane M; van Kasteren, Marjo E; van Eeden, Arne; Posthouwer, Dirk; Claassen, Mark A; Dofferhoff, Anton S; Verhagen, Dominique W M; Bierman, Wouter F; Lettinga, Kamilla D; Kroon, Frank P; Delsing, Corine E; Groeneveld, Paul H; Soetekouw, Robert; Peters, Edgar J; Hullegie, Sebastiaan J; Popping, Stephanie; van de Vijver, David A M C; Boucher, Charles A; Arends, Joop E; Rijnders, Bart J

2018-04-17

Direct-acting antivirals (DAAa) cure hepatitis C virus (HCV) infections in 95% of infected patients. Modeling studies predict that universal HCV treatment will lead to a decrease in the incidence of new infections but real-life data are lacking. The incidence of HCV among Dutch human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) has been high for >10 years. In 2015 DAAs became available to all Dutch HCV patients and resulted in a rapid treatment uptake in HIV-positive MSM. We assessed whether this uptake was followed by a decrease in the incidence of HCV infections. Two prospective studies of treatment for acute HCV infection enrolled patients in 17 Dutch HIV centers, having 76% of the total HIV-positive MSM population in care in the Netherlands. Patients were recruited in 2014 and 2016, the years before and after unrestricted DAA availability. We compared the HCV incidence in both years. The incidence of acute HCV infection decreased from 93 infections during 8290 person-years of follow-up (PYFU) in 2014 (11.2/1000 PYFU; 95% confidence interval [CI], 9.1-13.7) to 49 during 8961 PYFU in 2016 (5.5/1000 PYFU; 4.1-7.2). The incidence rate ratio of 2016 compared with 2014 was 0.49 (95% CI, .35-.69). Simultaneously, a significant increase in the percentage positive syphilis (+2.2%) and gonorrhea (+2.8%) tests in HIV-positive MSM was observed at sexual health clinics across the Netherlands and contradicts a decrease in risk behavior as an alternative explanation. Unrestricted DAA availability in the Netherlands was followed by a 51% decrease in acute HCV infections among HIV-positive MSM.

Analysis of resistance-associated substitutions in acute hepatitis C virus infection by deep sequencing across six genotypes and three continents.

PubMed

Eltahla, A A; Rodrigo, C; Betz-Stablein, B; Grebely, J; Applegate, T; Luciani, F; Schinkel, J; Dore, G J; Page, K; Bruneau, J; Morris, M D; Cox, A L; Kim, A Y; Shoukry, N H; Lauer, G M; Maher, L; Hellard, M; Prins, M; Lloyd, A R; Bull, R A

2017-01-01

Several direct-acting antivirals (DAAs) have been approved for the treatment of chronic hepatitis C virus (HCV) infections, opening the door to highly effective interferon-free treatment regimens. Resistance-associated substitutions (RASs) have been reported both in treatment-naïve patients and following treatment with protease (NS3), phosphoprotein (NS5A) and polymerase (NS5B) inhibitors. The prevalence of naturally occurring RASs in untreated HCV-infected individuals has mostly been analysed in those infected with genotype 1 (GT1), in the late phase of infection, and only within limited regions of the genome. Furthermore, the geographic distribution of RASs remains poorly characterized. In this study, we used next-generation sequencing to analyse full-length HCV genomes for the prevalence of RASs in acute HCV infections identified in nine international prospective cohorts. RASs were analysed in 179 participants infected with all six major HCV genotypes (GT1-GT6), and the geographic distribution of RASs was assessed in 107 GT1a and GT3a samples. While RASs were detected at varied frequencies across the three genomic regions, and between genotypes, RASs relevant to multiple DAAs in the leading IFN-free regimens were rarely detected in combination. Low-frequency RASs (<10% of the viral population) were also shown to have a GT-specific distribution. The main RASs with geographic associations were NS3 Q80K in GT1a samples and NS5B N142T in GT3a. These data provide the backdrop for prospective surveillance of RASs during DAA treatment scale-up. © 2016 John Wiley & Sons Ltd.

Identification of drug resistance and immune-driven variations in hepatitis C virus (HCV) NS3/4A, NS5A and NS5B regions reveals a new approach toward personalized medicine.

PubMed

Ikram, Aqsa; Obaid, Ayesha; Awan, Faryal Mehwish; Hanif, Rumeza; Naz, Anam; Paracha, Rehan Zafar; Ali, Amjad; Janjua, Hussnain Ahmed

2017-01-01

Cellular immune responses (T cell responses) during hepatitis C virus (HCV) infection are significant factors for determining the outcome of infection. HCV adapts to host immune responses by inducing mutations in its genome at specific sites that are important for HLA processing/presentation. Moreover, HCV also adapts to resist potential drugs that are used to restrict its replication, such as direct-acting antivirals (DAAs). Although DAAs have significantly reduced disease burden, resistance to these drugs is still a challenge for the treatment of HCV infection. Recently, drug resistance mutations (DRMs) observed in HCV proteins (NS3/4A, NS5A and NS5B) have heightened concern that the emergence of drug resistance may compromise the effectiveness of DAAs. Therefore, the NS3/4A, NS5A and NS5B drug resistance variations were investigated in this study, and their prevalence was examined in a large number of protein sequences from all HCV genotypes. Furthermore, potential CD4 + and CD8 + T cell epitopes were predicted and their overlap with genetic variations was explored. The findings revealed that many reported DRMs within NS3/4A, NS5A and NS5B are not drug-induced; rather, they are already present in HCV strains, as they were also detected in HCV-naïve patients. This study highlights several hot spots in which HLA and drug selective pressure overlap. Interestingly, these overlapping mutations were frequently observed among many HCV genotypes. This study implicates that knowledge of the host HLA type and HCV subtype/genotype can provide important information in defining personalized therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Antiviral Regulation in Porcine Monocytic Cells at Different Activation States

PubMed Central

Rowland, Raymond R. R.

2014-01-01

ABSTRACT Monocytic cells, including macrophages and dendritic cells, exist in different activation states that are critical to the regulation of antimicrobial immunity. Many pandemic viruses are monocytotropic, including porcine reproductive and respiratory syndrome virus (PRRSV), which directly infects subsets of monocytic cells and interferes with antiviral responses. To study antiviral responses in PRRSV-infected monocytic cells, we characterized inflammatory cytokine responses and genome-wide profiled signature genes to investigate response pathways in uninfected and PRRSV-infected monocytic cells at different activation states. Our findings showed suppressed interferon (IFN) production in macrophages in non-antiviral states and an arrest of lipid metabolic pathways in macrophages at antiviral states. Importantly, porcine monocytic cells at different activation states were susceptible to PRRSV and responded differently to viral infection. Based on Gene Ontology (GO) analysis, two approaches were used to potentiate antiviral activity: (i) pharmaceutical modulation of cellular lipid metabolism and (ii) in situ PRRSV replication-competent expression of interferon alpha (IFN-α). Both approaches significantly suppressed exogenous viral infection in monocytic cells. In particular, the engineered IFN-expressing PRRSV strain eliminated exogenous virus infection and sustained cell viability at 4 days postinfection in macrophages. These findings suggest an intricate interaction of viral infection with the activation status of porcine monocytic cells. An understanding and integration of antiviral infection with activation status of monocytic cells may provide a means of potentiating antiviral immunity. IMPORTANCE Activation statuses of monocytic cells, including monocytes, macrophages (Mϕs), and dendritic cells (DCs), are critically important for antiviral immunity. Unfortunately, the activation status of porcine monocytic cells or how cell activation status

Changing the face of hepatitis C management – the design and development of sofosbuvir

PubMed Central

Noell, Bennett C; Besur, Siddesh V; deLemos, Andrew S

2015-01-01

The availability of direct-acting antiviral (DAA) therapy has launched a new era in the management of chronic hepatitis C. Sofosbuvir, a uridine nucleotide analog that inhibits the hepatitis C RNA-dependent RNA polymerase, is the backbone of chronic hepatitis C therapy. Acting at the catalytic site of the polymerase, sofosbuvir is highly potent in suppressing viral replication and has a high genetic barrier to resistance. Sofosbuvir is effective across all hepatitis C genotypes, and is a mainstay of interferon-free combination therapy. In Phase II and III studies, genotype 1 patients who took sofosbuvir in combination with another DAA such as the NS3-4A protease inhibitor, simeprevir, or the NS5A replication complex inhibitors, ledipasvir or daclatasvir, achieved a sustained virologic response rate of over 90%. Harvoni®, a combination tablet of sofosbuvir and ledipasvir, dosed once daily is recommended for 24 weeks for treatment-experienced genotype 1 patients with cirrhosis, but 12 weeks of therapy is sufficient for all other populations. While genotype 2 (12 weeks or 16 weeks) and treatment-naïve genotype 3 patients (24 weeks) have excellent response rates with sofosbuvir and ribavirin, treatment-experienced cirrhotic genotype 3 patients may need the addition of another DAA such as daclatasvir. Sofosbuvir is efficacious in special populations such as HIV–hepatitis C virus-coinfected patients and liver transplant recipients and has already made a profound impact in these groups. Since it is renally eliminated, patients with advanced kidney disease or on dialysis must await dosing recommendations. Sofosbuvir-based regimens appear to be well tolerated with headache and fatigue being the most common side effects. The opportunity to cure patients with hepatitis C with sofosbuvir combination therapy is likely to change the future for our patients, particularly if the emphasis shifts to identifying those patients unaware that they are infected and providing

Simplification of antiviral hepatitis C virus therapy to support expanded access in resource-limited settings.

PubMed

Ford, Nathan; Swan, Tracy; Beyer, Peter; Hirnschall, Gottfried; Easterbrook, Philippa; Wiktor, Stefan

2014-11-01

Currently, access to treatment for HCV is limited, with treatment rates lowest in the more resource-limited countries, including those countries with the highest prevalence. The use of oral DAAs has the potential to provide treatment at scale by offering opportunities to simplify drug regimens, laboratory requirements, and service delivery models. Key desirable characteristics of future HCV treatment regimens include high efficacy, tolerability, pan-genotype activity, short treatment duration, oral therapy, affordability, and availability as fixed-dose combination. Using such a regimen, HCV treatment delivery could be greatly simplified. Treatment could be initiated following confirmation of the presence of viraemia, with an initial assessment of the stage of liver disease. A combination DAA therapy that is safe and effective across genotypes could remove the need for genotyping and intermediary viral load assessments for response-guided therapy and reduce the need for adverse event monitoring. Simpler, safer, shorter therapy will also facilitate simplified service delivery, including task shifting, decentralization, and integration of treatment and care. The opportunity to scale up HCV treatment using such delivery approaches will depend on efforts needed to guarantee that the new DAAs are affordable in low-income settings. This will require the engagement of all stakeholders, ranging from the companies developing these new treatments, WHO and other international organizations, including procurement and funding mechanisms, governments and civil society. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Sofosbuvir, Velpatasvir, and Voxilaprevir for Previously Treated HCV Infection.

PubMed

Bourlière, Marc; Gordon, Stuart C; Flamm, Steven L; Cooper, Curtis L; Ramji, Alnoor; Tong, Myron; Ravendhran, Natarajan; Vierling, John M; Tran, Tram T; Pianko, Stephen; Bansal, Meena B; de Lédinghen, Victor; Hyland, Robert H; Stamm, Luisa M; Dvory-Sobol, Hadas; Svarovskaia, Evguenia; Zhang, Jie; Huang, K C; Subramanian, G Mani; Brainard, Diana M; McHutchison, John G; Verna, Elizabeth C; Buggisch, Peter; Landis, Charles S; Younes, Ziad H; Curry, Michael P; Strasser, Simone I; Schiff, Eugene R; Reddy, K Rajender; Manns, Michael P; Kowdley, Kris V; Zeuzem, Stefan

2017-06-01

Patients who are chronically infected with hepatitis C virus (HCV) and who do not have a sustained virologic response after treatment with regimens containing direct-acting antiviral agents (DAAs) have limited retreatment options. We conducted two phase 3 trials involving patients who had been previously treated with a DAA-containing regimen. In POLARIS-1, patients with HCV genotype 1 infection who had previously received a regimen containing an NS5A inhibitor were randomly assigned in a 1:1 ratio to receive either the nucleotide polymerase inhibitor sofosbuvir, the NS5A inhibitor velpatasvir, and the protease inhibitor voxilaprevir (150 patients) or matching placebo (150 patients) once daily for 12 weeks. Patients who were infected with HCV of other genotypes (114 patients) were enrolled in the sofosbuvir-velpatasvir-voxilaprevir group. In POLARIS-4, patients with HCV genotype 1, 2, or 3 infection who had previously received a DAA regimen but not an NS5A inhibitor were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir-voxilaprevir (163 patients) or sofosbuvir-velpatasvir (151 patients) for 12 weeks. An additional 19 patients with HCV genotype 4 infection were enrolled in the sofosbuvir-velpatasvir-voxilaprevir group. In the three active-treatment groups, 46% of the patients had compensated cirrhosis. In POLARIS-1, the rate of sustained virologic response was 96% with sofosbuvir-velpatasvir-voxilaprevir, as compared with 0% with placebo. In POLARIS-4, the rate of response was 98% with sofosbuvir-velpatasvir-voxilaprevir and 90% with sofosbuvir-velpatasvir. The most common adverse events were headache, fatigue, diarrhea, and nausea. In the active-treatment groups in both trials, the percentage of patients who discontinued treatment owing to adverse events was 1% or lower. Sofosbuvir-velpatasvir-voxilaprevir taken for 12 weeks provided high rates of sustained virologic response among patients across HCV genotypes in whom treatment with a DAA regimen

The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

PubMed Central

Wang, Wei; Wang, Shi-Xin; Guan, Hua-Shi

2012-01-01

Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail. PMID:23235364

Antiviral potential of a diterpenoid compound sugiol from Metasequoia glyptostroboides.

PubMed

Bajpai, Vivek K; Kim, Na-Hyung; Kim, Kangmin; Kang, Sun Chul

2016-05-01

This research reports first time antiviral activity of sugiol, a diterpenoid isolated from Metasequoia glyptostroboides in terms of its ability to inhibit in vitro growth of H1N1 influenza virus. Antiviral potential of sugiol was evaluated through hcytopathogenic reduction assay using Madin-Darby canine kidney (MDCK) cell line. Sugiol (500 μg/ml) was found to exhibit considerable anti-cytopathic effect on MDCK cell line confirming its antiviral efficacy against H1N1 influenza virus. These findings strongly reinforce the suggestion that sugiol could be a candidate of choice in combinational regimen with potential antiviral efficacy.

Antiviral activity of aconite alkaloids from Aconitum carmichaelii Debx.

PubMed

Xu, Weiming; Zhang, Min; Liu, Hongwu; Wei, Kun; He, Ming; Li, Xiangyang; Hu, Deyu; Yang, Song; Zheng, Yuguo

2017-12-22

Four diterpenoid alkaloids, namely, (a) hypaconitine, (b) songorine, (c) mesaconitine and (d) aconitine, were isolated from the ethanol root extract of Aconitum carmichaelii Debx. The antiviral activities of these alkaloids against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) were evaluated. Antiviral activity test in vivo showed that compounds a and c, which were C19-diterpenoid alkaloids, showed inactivation efficacy values of 82.4 and 85.6% against TMV at 500 μg/mL, respectively. By contrast, compound c presented inactivation activity of 52.1% against CMV at 500 μg/mL, which was almost equal to that of the commercial Ningnanmycin (87.1% inactivation activity against TMV and 53.8% inactivation activity against CMV). C19-Diterpenoid alkaloids displayed moderate to high antiviral activity against TMV and CMV at 500 μg/mL, dosage plays an important role in antiviral activities. This paper is the first report on the evolution of aconite diterpenoid alkaloids for antiviral activity against CMV.

Potential Antiviral Agents from Marine Fungi: An Overview

PubMed Central

Zorofchian Moghadamtousi, Soheil; Nikzad, Sonia; Abdul Kadir, Habsah; Abubakar, Sazaly; Zandi, Keivan

2015-01-01

Biodiversity of the marine world is only partially subjected to detailed scientific scrutiny in comparison to terrestrial life. Life in the marine world depends heavily on marine fungi scavenging the oceans of lifeless plants and animals and entering them into the nutrient cycle by. Approximately 150 to 200 new compounds, including alkaloids, sesquiterpenes, polyketides, and aromatic compounds, are identified from marine fungi annually. In recent years, numerous investigations demonstrated the tremendous potential of marine fungi as a promising source to develop new antivirals against different important viruses, including herpes simplex viruses, the human immunodeficiency virus, and the influenza virus. Various genera of marine fungi such as Aspergillus, Penicillium, Cladosporium, and Fusarium were subjected to compound isolation and antiviral studies, which led to an illustration of the strong antiviral activity of a variety of marine fungi-derived compounds. The present review strives to summarize all available knowledge on active compounds isolated from marine fungi with antiviral activity. PMID:26204947

Prophylaxis Among Hepatitis B Core Antibody-positive Deceased-donor Liver Transplant Recipients: Hepatitis B Immunoglobulin Plus Oral Antiviral Agents Versus Antiviral Agents Alone: A Single-center Experience.

PubMed

Malik, Mohammad U; Ucbilek, Enver; Trilianos, Panagiotis; Cameron, Andrew M; Gurakar, Ahmet

2017-04-01

Hepatitis B core antibody immunoglobulin G seropositivity is evidence of past exposure to hepatitis B virus. Donor or recipient hepatitis B core antibody positivity may pose a risk of reactivation, especially early after liver transplant. Although most centers advocate using antiviral agents plus hepatitis B immunoglobulin, some have recently relied on antivirals only as prophylaxis after liver transplant. Here, we retrospectively investigated patient survival in hepatitis B core antibody-positive recipients, comparing those treated with antivirals plus hepatitis B immunoglobulin versus antivirals alone. After Internal Review Board approval, we reviewed medical records of deceased-donor liver transplant recipients between 1995 and 2013. Demographic characteristics, transplant indication, hepatitis B core antibody status, time to death, and type of posttransplant prophylaxis were recorded. We also recorded whether donors showed hepatitis B core antibody positivity. Patients who died within 30 days of liver transplant were excluded. There were 148 hepatitis B core antibody-positive recipients. Prophylaxis was given to 75 recipients after transplant: 8 (5%) received hepatitis B immunoglobulin, 22 (15%) received antivirals, and 45 (30%) received the combination. There were 34 deaths: 3 (38%) in hepatitis B immunoglobulin only, 3 (14%) in antiviral only, 8 (18%) in the combination, and 20 (27%) in no prophylaxis groups. One- and 5-year survival rates were similar for binary comparisons among prophylaxis groups (P > .05). Preliminary results support the current practice of using hepatitis B immunoglobulin plus antivirals for prophylaxis after liver transplant. The similar survival benefit with the combination versus antiviral agents alone suggests equal effectivity for prophylaxis posttransplant. However, a clear benefit of antivirals was not evident in our analysis. Future larger prospective studies are warranted to identify potential benefits of using antivirals alone

Innate and intrinsic antiviral immunity in Drosophila.

PubMed

Mussabekova, Assel; Daeffler, Laurent; Imler, Jean-Luc

2017-06-01

The fruit fly Drosophila melanogaster has been a valuable model to investigate the genetic mechanisms of innate immunity. Initially focused on the resistance to bacteria and fungi, these studies have been extended to include antiviral immunity over the last decade. Like all living organisms, insects are continually exposed to viruses and have developed efficient defense mechanisms. We review here our current understanding on antiviral host defense in fruit flies. A major antiviral defense in Drosophila is RNA interference, in particular the small interfering (si) RNA pathway. In addition, complex inducible responses and restriction factors contribute to the control of infections. Some of the genes involved in these pathways have been conserved through evolution, highlighting loci that may account for susceptibility to viral infections in humans. Other genes are not conserved and represent species-specific innovations.

Synthesis and antiviral activity of certain second generation methylenecyclopropane nucleosides

PubMed Central

Williams, John D.; Khan, Atiyya R.; Harden, Emma A.; Hartline, Caroll B.; Jefferson, Geraldine M.; Keith, Kathy A.; Prichard, Mark N.; Zemlicka, Jiri; Peet, Norton P.; Bowlin, Terry L.

2012-01-01

A second-generation series of substituted methylenecyclopropane nucleosides (MCPNs) has been synthesized and evaluated for antiviral activity against a panel of human herpesviruses, and for cytotoxicity. Although alkylated 2,6-diaminopurine analogs showed little antiviral activity, the compounds containing ether and thioether substituents at the 6-position of the purine did demonstrate potent and selective antiviral activity against several different human herpesviruses. In the 6-alkoxy series, antiviral activity depended on the length of the ether carbon chain, with the optimum chain length being about four carbon units long. For the corresponding thioethers, compounds containing secondary thioethers were more potent than those with primary thioethers. PMID:22607883

Cost-effectiveness of using kidneys from Hepatitis C nucleic acid test positive donors for transplantation in Hepatitis C negative recipients.

PubMed

Kadatz, Matthew; Klarenbach, Scott; Gill, Jagbir; Gill, John S

2018-05-23

Kidneys from deceased donors that are hepatitis C (HCV) nucleic acid test (NAT) positive are infrequently used for transplantation in HCV negative patients due to concerns of disease transmission. With the development of direct acting antivirals (DAA's) for HCV, there is now potential to use these kidneys in HCV negative candidates. However, the high cost of DAAs poses a challenge to adoption of this strategy. We created a Markov model to examine the cost-effectiveness of using deceased donors infected with HCV for kidney transplantation in uninfected waitlist candidates. In the primary analysis this strategy was cost saving and improved health outcomes compared to remaining on the waitlist for an additional two or more years to receive a HCV negative transplant. The strategy was also cost-effective with an incremental cost-effectiveness ratio of $56018 per quality adjusted life year (QALY) from the payer perspective, and $4647 per QALY from the societal perspective, compared to remaining on the waitlist for one additional year. The results were consistent in one way and probabilistic sensitivity analyses. We conclude that the use of kidneys from deceased donors with HCV infection are likely to lead to improved clinical outcomes at reduced cost for HCV negative transplant candidates. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The growth and potential of human antiviral monoclonal antibody therapeutics.

PubMed

Marasco, Wayne A; Sui, Jianhua

2007-12-01

Monoclonal antibodies (mAbs) have long provided powerful research tools for virologists to understand the mechanisms of virus entry into host cells and of antiviral immunity. Even so, commercial development of human (or humanized) mAbs for the prophylaxis, preemptive and acute treatment of viral infections has been slow. This is surprising, as new antibody discovery tools have increased the speed and precision with which potent neutralizing human antiviral mAbs can be identified. As longstanding barriers to antiviral mAb development, such as antigenic variability of circulating viral strains and the ability of viruses to undergo neutralization escape, are being overcome, deeper insight into the mechanisms of mAb action and engineering of effector functions are also improving the efficacy of antiviral mAbs. These successes, in both industrial and academic laboratories, coupled with ongoing changes in the biomedical and regulatory environments, herald an era when the commercial development of human antiviral mAb therapies will likely surge.

Diagnosis and antiviral intervention strategies for mitigating an influenza epidemic.

PubMed

Moss, Robert; McCaw, James M; McVernon, Jodie

2011-02-04

Many countries have amassed antiviral stockpiles for pandemic preparedness. Despite extensive trial data and modelling studies, it remains unclear how to make optimal use of antiviral stockpiles within the constraints of healthcare infrastructure. Modelling studies informed recommendations for liberal antiviral distribution in the pandemic phase, primarily to prevent infection, but failed to account for logistical constraints clearly evident during the 2009 H1N1 outbreaks. Here we identify optimal delivery strategies for antiviral interventions accounting for logistical constraints, and so determine how to improve a strategy's impact. We extend an existing SEIR model to incorporate finite diagnostic and antiviral distribution capacities. We evaluate the impact of using different diagnostic strategies to decide to whom antivirals are delivered. We then determine what additional capacity is required to achieve optimal impact. We identify the importance of sensitive and specific case ascertainment in the early phase of a pandemic response, when the proportion of false-positive presentations may be high. Once a substantial percentage of ILI presentations are caused by the pandemic strain, identification of cases for treatment on syndromic grounds alone results in a greater potential impact than a laboratory-dependent strategy. Our findings reinforce the need for a decentralised system capable of providing timely prophylaxis. We address specific real-world issues that must be considered in order to improve pandemic preparedness policy in a practical and methodologically sound way. Provision of antivirals on the scale proposed for an effective response is infeasible using traditional public health outbreak management and contact tracing approaches. The results indicate to change the transmission dynamics of an influenza epidemic with an antiviral intervention, a decentralised system is required for contact identification and prophylaxis delivery, utilising a range of

Innate and intrinsic antiviral immunity in Drosophila

PubMed Central

Mussabekova, Assel; Daeffler, Laurent; Imler, Jean-Luc

2017-01-01

The fruitfly Drosophila melanogaster has been a valuable model to investigate the genetic mechanisms of innate immunity. Initially focused on the resistance to bacteria and fungi, these studies have been extended to include antiviral immunity over the last decade. Like all living organisms, insects are continually exposed to viruses and have developed efficient defense mechanisms. We review here our current understanding on antiviral host-defense in fruit flies. A major antiviral defense in Drosophila is RNA interference, in particular the small interfering (si) RNA pathway. In addition, complex inducible responses and restriction factors contribute to the control of infections. Some of the genes involved in these pathways have been conserved through evolution, highlighting loci that may account for susceptibility to viral infections in humans. Other genes are not conserved and represent species-specific innovations. PMID:28102430

Polysaccharide and extracts from Lentinula edodes: structural features and antiviral activity

PubMed Central

2012-01-01

Background Lentinula edodes, known as shiitake, has been utilized as food, as well as, in popular medicine, moreover, compounds isolated from its mycelium and fruiting body have shown several therapeutic properties. The aim of this study was to determine the antiviral activity of aqueous (AqE) and ethanol (EtOHE) extracts and polysaccharide (LeP) from Lentinula edodes in the replication of poliovirus type 1 (PV-1) and bovine herpes virus type 1 (BoHV-1). Methods The time-of-addition assay was performed at the times -2, -1, 0, 1 and 2 h of the infection. The virucidal activity and the inhibition of viral adsorption were also evaluated. Plaque assay was used to monitor antiviral activity throughout. Results The AqE and LeP were more effective when added at 0 h of infection, however, EtOHE was more effective at the times 1 h and 2 h of the infection. AqE, EtOHE and LeP showed low virucidal activity, and the inhibition of viral adsorption was not significant. Conclusions The results allowed us to conclude that AqE, EtOHE and LeP act on the initial processes of the replication of both strains of virus. PMID:22336004

Cross-Genotypic Examination of Hepatitis C Virus Polymerase Inhibitors Reveals a Novel Mechanism of Action for Thumb Binders

PubMed Central

Eltahla, Auda A.; Tay, Enoch; Douglas, Mark W.

2014-01-01

Direct-acting antivirals (DAAs) targeting proteins encoded by the hepatitis C virus (HCV) genome have great potential for the treatment of HCV infections. However, the efficacy of DAAs designed to target genotype 1 (G1) HCV against non-G1 viruses has not been characterized fully. In this study, we investigated the inhibitory activities of nonnucleoside inhibitors (NNIs) against the HCV RNA-dependent RNA polymerase (RdRp). We examined the ability of six NNIs to inhibit G1b, G2a, and G3a subgenomic replicons in cell culture, as well as in vitro transcription by G1b and G3a recombinant RdRps. Of the six G1 NNIs, only the palm II binder nesbuvir demonstrated activity against G1, G2, and G3 HCV, in both replicon and recombinant enzyme models. The thumb I binder JTK-109 also inhibited G1b and G3a replicons and recombinant enzymes but was 41-fold less active against the G2a replicon. The four other NNIs, which included a palm I binder (setrobuvir), two thumb II binders (lomibuvir and filibuvir), and a palm β-hairpin binder (tegobuvir), all showed at least 40-fold decreases in potency against G2a and G3a replicons and the G3a enzyme. This antiviral resistance was largely conferred by naturally occurring amino acid residues in the G2a and G3a RdRps that are associated with G1 resistance. Lomibuvir and filibuvir (thumb II binders) inhibited primer-dependent but not de novo activity of the G1b polymerase. Surprisingly, these compounds instead specifically enhanced the de novo activity at concentrations of ≥100 nM. These findings highlight a potential differential mode of RdRp inhibition for HCV NNIs, depending on their prospective binding pockets, and also demonstrate a surprising enhancement of de novo activity for thumb RdRp binders. These results also provide a better understanding of the antiviral coverage for these polymerase inhibitors, which will likely be used in future combinational interferon-free therapies. PMID:25246395

New approaches in the treatment of hepatitis C

PubMed Central

González-Grande, Rocío; Jiménez-Pérez, Miguel; González Arjona, Carolina; Mostazo Torres, José

2016-01-01

About 130-170 million people, is estimated to be infected with the hepatitis C virus (HCV). Chronic HCV infection is one of the leading causes of liver-related death and in many countries it is the primary reason for having a liver transplant. The main aim of antiviral treatment is to eradicate the virus. Until a few years ago the only treatment strategy was based on the combination of pegylated interferon and ribavirin (PEG/RBV). However, in genotypes 1 and 4 the rates of viral response did not surpass 50%, reaching up to 80% in the rest. In 2011 approval was given for the first direct acting antiviral agents (DAA), boceprevir and telaprevir, for treatment of genotype 1, in combination with traditional dual therapy. This strategy managed to increase the rates of sustained viral response (SVR) in both naive patients and in retreated patients, but with greater toxicity, interactions and cost, as well as being less safe in patients with advanced disease, in whom this treatment can trigger decompensation or even death. The recent, accelerated incorporation since 2013 of new more effective DAA, with pan-genomic properties and excellent tolerance, besides increasing the rates of SVR (even up to 100%), has also created a new scenario: shorter therapies, less toxicity and regimens free of PEG/RBV. This has enabled their almost generalised applicability in all patients. However, it should be noted that most of the scientific evidence available is based on expert opinion, case-control series, cohort studies and phase 2 and 3 trials, some with a reduced number of patients and select groups. Few data are currently available about the use of these drugs in daily clinical practice, particularly in relation to the appearance of side effects and interactions with other drugs, or their use in special populations or persons with the less common genotypes. This situation suggests the need for the generalised implementation of registries of patients receiving antiviral therapy. The

Cytomegalovirus Antivirals and Development of Improved Animal Models

PubMed Central

McGregor, Alistair; Choi, K. Yeon

2015-01-01

Introduction Cytomegalovirus (CMV) is a ubiquitous pathogen that establishes a life long asymptomatic infection in healthy individuals. Infection of immunesuppressed individuals causes serious illness. Transplant and AIDS patients are highly susceptible to CMV leading to life threatening end organ disease. Another vulnerable population is the developing fetus in utero, where congenital infection can result in surviving newborns with long term developmental problems. There is no vaccine licensed for CMV and current antivirals suffer from complications associated with prolonged treatment. These include drug toxicity and emergence of resistant strains. There is an obvious need for new antivirals. Candidate intervention strategies are tested in controlled pre-clinical animal models but species specificity of HCMV precludes the direct study of the virus in an animal model. Areas covered This review explores the current status of CMV antivirals and development of new drugs. This includes the use of animal models and the development of new improved models such as humanized animal CMV and bioluminescent imaging of virus in animals in real time. Expert Opinion Various new CMV antivirals are in development, some with greater spectrum of activity against other viruses. Although the greatest need is in the setting of transplant patients there remains an unmet need for a safe antiviral strategy against congenital CMV. This is especially important since an effective CMV vaccine remains an elusive goal. In this capacity greater emphasis should be placed on suitable pre-clinical animal models and greater collaboration between industry and academia. PMID:21883024

Antiviral lead compounds from marine sponges.

PubMed

Sagar, Sunil; Kaur, Mandeep; Minneman, Kenneth P

2010-10-11

Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hoped to be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

Autoimmune disease: A role for new anti-viral therapies?

PubMed

Dreyfus, David H

2011-12-01

Many chronic human diseases may have an underlying autoimmune mechanism. In this review, the author presents a case of autoimmune CIU (chronic idiopathic urticaria) in stable remission after therapy with a retroviral integrase inhibitor, raltegravir (Isentress). Previous reports located using the search terms "autoimmunity" and "anti-viral" and related topics in the pubmed data-base are reviewed suggesting that novel anti-viral agents such as retroviral integrase inhibitors, gene silencing therapies and eventually vaccines may provide new options for anti-viral therapy of autoimmune diseases. Cited epidemiologic and experimental evidence suggests that increased replication of epigenomic viral pathogens such as Epstein-Barr Virus (EBV) in chronic human autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus Erythematosus (SLE), and multiple sclerosis (MS) may activate endogenous human retroviruses (HERV) as a pathologic mechanism. Memory B cells are the reservoir of infection of EBV and also express endogenous retroviruses, thus depletion of memory b-lymphocytes by monoclonal antibodies (Rituximab) may have therapeutic anti-viral effects in addition to effects on B-lymphocyte presentation of both EBV and HERV superantigens. Other novel anti-viral therapies of chronic autoimmune diseases, such as retroviral integrase inhibitors, could be effective, although not without risk. Copyright © 2011 Elsevier B.V. All rights reserved.

Nucleic acid-induced antiviral immunity in invertebrates: an evolutionary perspective.

PubMed

Wang, Pei-Hui; Weng, Shao-Ping; He, Jian-Guo

2015-02-01

Nucleic acids derived from viral pathogens are typical pathogen associated molecular patterns (PAMPs). In mammals, the recognition of viral nucleic acids by pattern recognition receptors (PRRs), which include Toll-like receptors (TLRs) and retinoic acid-inducible gene (RIG)-I-like receptors (RLRs), induces the release of inflammatory cytokines and type I interferons (IFNs) through the activation of nuclear factor κB (NF-κB) and interferon regulatory factor (IRF) 3/7 pathways, triggering the host antiviral state. However, whether nucleic acids can induce similar antiviral immunity in invertebrates remains ambiguous. Several studies have reported that nucleic acid mimics, especially dsRNA mimic poly(I:C), can strongly induce non-specific antiviral immune responses in insects, shrimp, and oyster. This behavior shows multiple similarities to the hallmarks of mammalian IFN responses. In this review, we highlight the current understanding of nucleic acid-induced antiviral immunity in invertebrates. We also discuss the potential recognition and regulatory mechanisms that confer non-specific antiviral immunity on invertebrate hosts. Copyright © 2014 Elsevier Ltd. All rights reserved.

RIOK3 Is an Adaptor Protein Required for IRF3-Mediated Antiviral Type I Interferon Production

PubMed Central

Feng, Jun; De Jesus, Paul D.; Su, Victoria; Han, Stephanie; Gong, Danyang; Wu, Nicholas C.; Tian, Yuan; Li, Xudong; Wu, Ting-Ting; Chanda, Sumit K.

2014-01-01

ABSTRACT Detection of cytosolic nucleic acids by pattern recognition receptors leads to the induction of type I interferons (IFNs) and elicits the innate immune response. We report here the identification of RIOK3 as a novel adaptor protein that is essential for the cytosolic nucleic acid-induced type I IFN production and for the antiviral response to gammaherpesvirus through two independent kinome-wide RNA interference screens. RIOK3 knockdown blocks both cytosolic double-stranded B-form DNA and double-stranded RNA-induced IRF3 activation and IFN-β production. In contrast, the overexpression of RIOK3 activates IRF3 and induces IFN-β. RIOK3 functions downstream of TBK1 and upstream of IRF3 activation. Furthermore, RIOK3 physically interacts with both IRF3 and TBK1 and is necessary for the interaction between TBK1 and IRF3. In addition, global transcriptome analysis shows that the expression of many gene involved antiviral responses is dependent on RIOK3. Thus, knockdown of RIOK3 inhibits cellular antiviral responses against both DNA and RNA viruses (herpesvirus and influenza A virus). Our data suggest that RIOK3 plays a critical role in the antiviral type I IFN pathway by bridging TBK1 and IRF3. IMPORTANCE The innate immune response, such as the production of type I interferons, acts as the first line of defense, limiting infectious pathogens directly and shaping the adaptive immune response. In this study, we identified RIOK3 as a novel regulator of the antiviral type I interferon pathway. Specifically, we found that RIOK3 physically interacts with TBK1 and IRF3 and bridges the functions between TBK1 and IRF3 in the activation of type I interferon pathway. The identification of a cellular kinase that plays a role the type I interferon pathway adds another level of complexity in the regulation of innate immunity and will have implications for developing novel strategies to combat viral infection. PMID:24807708

Treatment of hepatitis C virus infection in patients with cirrhosis and predictive value of model for end-stage liver disease: Analysis of data from the Hepa-C registry.

PubMed

Fernández Carrillo, Carlos; Lens, Sabela; Llop, Elba; Pascasio, Juan Manuel; Crespo, Javier; Arenas, Juan; Fernández, Inmaculada; Baliellas, Carme; Carrión, José Antonio; de la Mata, Manuel; Buti, Maria; Castells, Lluís; Albillos, Agustín; Romero, Manuel; Turnes, Juan; Pons, Clara; Moreno-Planas, José María; Moreno-Palomares, José Javier; Fernández-Rodriguez, Conrado; García-Samaniego, Javier; Prieto, Martín; Fernández Bermejo, Miguel; Salmerón, Javier; Badia, Ester; Salcedo, Magdalena; Herrero, José Ignacio; Granados, Rafael; Blé, Michel; Mariño, Zoe; Calleja, José Luis

2017-06-01

Direct-acting antiviral agents (DAAs) are highly effective and well tolerated in patients with chronic hepatitis C virus infection, including those with compensated cirrhosis. However, fewer data are available in patients with more advanced liver disease. Our retrospective, noninterventional, national, multicenter study in patients from the Spanish Hepa-C registry investigated the effectiveness and safety of interferon-free DAA regimens in patients with advanced liver disease, including those with decompensated cirrhosis, in routine practice (all currently approved regimens were registered). Patients transplanted during treatment or within 12 weeks of completing treatment were excluded. Among 843 patients with cirrhosis (Child-Turcotte-Pugh [CTP] class A, n = 564; CTP class B/C, n = 175), 90% achieved sustained virologic response 12 weeks after treatment (SVR12). Significant differences in SVR12 and relapse rates were observed between CTP class A and CTP class B/C patients (94% versus 78%, and 4% versus 14%, respectively; both P < 0.001). Serious adverse events (SAEs) were more common in CTP class B/C versus CTP class A patients (50% versus 12%, respectively; P < 0.001). Incident decompensation was the most common serious adverse event (7% overall). Death rate during the study period was 16/843 (2%), significantly higher among CTP class B/C versus CTP class A patients (6.4% versus 0.9%; P < 0.001). Baseline Model for End-Stage Liver Disease (MELD) score alone (cut-off 18) was the best predictor of survival. Patients with decompensated cirrhosis receiving DAAs present lower response rates and experience more SAEs. In this setting, a MELD score ≥18 may help clinicians to identify those patients with a higher risk of complications and to individualize treatment decisions. (Hepatology 2017;65:1810-1822). © 2017 by the American Association for the Study of Liver Diseases.

Reaching hepatitis C virus elimination targets requires health system interventions to enhance the care cascade.

PubMed

Scott, Nick; Doyle, Joseph S; Wilson, David P; Wade, Amanda; Howell, Jess; Pedrana, Alisa; Thompson, Alexander; Hellard, Margaret E

2017-09-01

Modelling suggests that achieving the World Health Organization's elimination targets for hepatitis C virus (HCV) is possible by scaling up use of direct-acting antiviral (DAA) therapy. However, poor linkage to health services and retention in care presents a major barrier, in particular among people who inject drugs (PWID). We identify and assess the cost-effectiveness of additional health system interventions required to achieve HCV elimination targets in Australia, a setting where all people living with HCV have access to DAA therapy. We used a dynamic HCV transmission and liver-disease progression mathematical model among current and former PWID, capturing testing, treatment and other features of the care cascade. Interventions tested were: availability of point-of-care RNA testing; increased testing of PWID; using biomarkers in place of liver stiffness measurement; and scaling up primary care treatment delivery. The projected treatment uptake in Australia reduced the number of people living with HCV from approximately 230,000 in 2015 to approximately 24,000 by 2030 and reduced incidence by 45%. However, the majority (74%) of remaining infections were undiagnosed and among PWID. Scaling up primary care treatment delivery and using biomarkers in place of liver stiffness measurement only reduced incidence by a further 1% but saved AU$32 million by 2030, with no change to health outcomes. Additionally replacing HCV antibody testing with point-of-care RNA testing increased healthcare cost savings to AU$62 million, increased incidence reduction to 64% and gained 11,000 quality-adjusted life years, but critically, additional screening of PWID was required to achieve HCV elimination targets. Even with unlimited and unrestricted access to HCV DAA treatment, interventions to improve the HCV cascade of care and target PWID will be required to achieve elimination targets. Copyright © 2017 Elsevier B.V. All rights reserved.

[Reviews on antiviral activity of chemical constituents from plants].

PubMed

Yang, Xian-Feng; Wang, Yu-Li; Xu, Wei-Ren

2008-01-01

This paper reviewed the progress in researches on antiviral activity of chemical constituents from plants in recent years, the antiviral activity and mechanism of action of flavonoids, alkaloids, terpenoids, coumarins and polysaccharoses were sammarszed, provided new leading compound for antivirus new drugs from the plares in prospect.

Overlapping and Distinct Molecular Determinants Dictating the Antiviral Activities of TRIM56 against Flaviviruses and Coronavirus

PubMed Central

Liu, Baoming; Li, Nan L.; Wang, Jie; Shi, Pei-Yong; Wang, Tianyi; Miller, Mark A.

2014-01-01

), and a human coronavirus, HCoV-OC43, but not encephalomyocarditis virus, a picornavirus. Further, we show that TRIM56-mediated inhibition of HCoV-OC43 multiplication depends solely on its E3 ligase activity, whereas its restriction of YFV and DENV2 requires both the E3 ligase activity and integrity of the C-terminal portion. The differing molecular determinants appear to accommodate distinct antiviral mechanisms TRIM56 adopts to target different families of viruses; while TRIM56 curbs intracellular YFV/DENV2 RNA replication, it acts at a later step in HCoV-OC43 life cycle. These novel findings illuminate the molecular basis of the versatility and specificity of TRIM56's antiviral activities against positive-strand RNA viruses. PMID:25253338

Overlapping and distinct molecular determinants dictating the antiviral activities of TRIM56 against flaviviruses and coronavirus.

PubMed

Liu, Baoming; Li, Nan L; Wang, Jie; Shi, Pei-Yong; Wang, Tianyi; Miller, Mark A; Li, Kui

2014-12-01

coronavirus, HCoV-OC43, but not encephalomyocarditis virus, a picornavirus. Further, we show that TRIM56-mediated inhibition of HCoV-OC43 multiplication depends solely on its E3 ligase activity, whereas its restriction of YFV and DENV2 requires both the E3 ligase activity and integrity of the C-terminal portion. The differing molecular determinants appear to accommodate distinct antiviral mechanisms TRIM56 adopts to target different families of viruses; while TRIM56 curbs intracellular YFV/DENV2 RNA replication, it acts at a later step in HCoV-OC43 life cycle. These novel findings illuminate the molecular basis of the versatility and specificity of TRIM56's antiviral activities against positive-strand RNA viruses. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Macromolecular Antiviral Agents against Zika, Ebola, SARS, and Other Pathogenic Viruses.

PubMed

Schandock, Franziska; Riber, Camilla Frich; Röcker, Annika; Müller, Janis A; Harms, Mirja; Gajda, Paulina; Zuwala, Kaja; Andersen, Anna H F; Løvschall, Kaja Borup; Tolstrup, Martin; Kreppel, Florian; Münch, Jan; Zelikin, Alexander N

2017-12-01

Viral pathogens continue to constitute a heavy burden on healthcare and socioeconomic systems. Efforts to create antiviral drugs repeatedly lag behind the advent of pathogens and growing understanding is that broad-spectrum antiviral agents will make strongest impact in future antiviral efforts. This work performs selection of synthetic polymers as novel broadly active agents and demonstrates activity of these polymers against Zika, Ebola, Lassa, Lyssa, Rabies, Marburg, Ebola, influenza, herpes simplex, and human immunodeficiency viruses. Results presented herein offer structure-activity relationships for these pathogens in terms of their susceptibility to inhibition by polymers, and for polymers in terms of their anionic charge and hydrophobicity that make up broad-spectrum antiviral agents. The identified leads cannot be predicted based on prior data on polymer-based antivirals and represent promising candidates for further development as preventive microbicides. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antiviral Screening of Multiple Compounds against Ebola Virus.

PubMed

Dowall, Stuart D; Bewley, Kevin; Watson, Robert J; Vasan, Seshadri S; Ghosh, Chandradhish; Konai, Mohini M; Gausdal, Gro; Lorens, James B; Long, Jason; Barclay, Wendy; Garcia-Dorival, Isabel; Hiscox, Julian; Bosworth, Andrew; Taylor, Irene; Easterbrook, Linda; Pitman, James; Summers, Sian; Chan-Pensley, Jenny; Funnell, Simon; Vipond, Julia; Charlton, Sue; Haldar, Jayanta; Hewson, Roger; Carroll, Miles W

2016-10-27

In light of the recent outbreak of Ebola virus (EBOV) disease in West Africa, there have been renewed efforts to search for effective antiviral countermeasures. A range of compounds currently available with broad antimicrobial activity have been tested for activity against EBOV. Using live EBOV, eighteen candidate compounds were screened for antiviral activity in vitro. The compounds were selected on a rational basis because their mechanisms of action suggested that they had the potential to disrupt EBOV entry, replication or exit from cells or because they had displayed some antiviral activity against EBOV in previous tests. Nine compounds caused no reduction in viral replication despite cells remaining healthy, so they were excluded from further analysis (zidovudine; didanosine; stavudine; abacavir sulphate; entecavir; JB1a; Aimspro; celgosivir; and castanospermine). A second screen of the remaining compounds and the feasibility of appropriateness for in vivo testing removed six further compounds (ouabain; omeprazole; esomeprazole; Gleevec; D-LANA-14; and Tasigna). The three most promising compounds (17-DMAG; BGB324; and NCK-8) were further screened for in vivo activity in the guinea pig model of EBOV disease. Two of the compounds, BGB324 and NCK-8, showed some effect against lethal infection in vivo at the concentrations tested, which warrants further investigation. Further, these data add to the body of knowledge on the antiviral activities of multiple compounds against EBOV and indicate that the scientific community should invest more effort into the development of novel and specific antiviral compounds to treat Ebola virus disease.

Closing the Gap: The Challenges of Treating Hepatitis C Virus Genotype 3 Infection.

PubMed

Martin, Michelle T; Deming, Paulina

2017-06-01

The efficacy of hepatitis C virus (HCV) treatment has increased over the last 5 years to nearly 100% for many patient groups. Patients with genotype (GT) 3 HCV infection, however, and specifically cirrhotic or treatment-experienced patients, have lower sustained virologic response (SVR) rates than patients with other GTs. Because GT 3 presents more clinical challenges than other GTs, this review focuses on the evolution and efficacy of direct-acting antiviral (DAA) treatment options for HCV GT 3 infection after the historical standard of care with pegylated interferon and ribavirin. Our objective was to review the SVR rates with available and late-pipeline DAAs for HCV GT 3 infection and discuss challenges with successful GT 3 treatment. Authors performed a literature search of the PubMed/MEDLINE database (inception to March 27, 2017) and narrowed the field to clinical trials published in English. Trials that evaluated alternative treatments, non-DAA historical treatment, and DAAs not currently indicated for HCV were excluded. Trials only involving patients with human immunodeficiency virus/HCV coinfection were also excluded. Additional trials were identified from a review of the ClinicalTrials.gov database. Authors further identified references from a review of literature citations and reviewed annual meeting abstracts from the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver for pipeline and real-world GT 3 data. Phase III trial data were not available to support all GT 3 treatment recommendations found in the guidelines. The SVR rates were lower in treatment-experienced and cirrhotic patients with GT 3 than other HCV populations. Treatment failure was associated with resistance to current treatment regimens. Clinical studies included patients with various levels of advanced liver disease, but few patients with decompensated cirrhosis were represented. Recent advances in pharmacologic treatment with DAAs

Awareness of the severity of liver disease re-examined using software-combined biomarkers of liver fibrosis and necroinflammatory activity

PubMed Central

Deckmyn, Olivier; Munteanu, Mona; Ngo, Yen; Drane, Fabienne; Castille, Jean Marie; Housset, Chantal; Ratziu, Vlad

2015-01-01

Background Effective antiviral treatment (direct-acting antiviral agents (DAAs)), the requirement for a fibrosis score to support DDA reimbursement and a screening strategy, such as the USA baby boomer campaign, should lead to an increased awareness of liver disease severity. Objective To compare the awareness of liver disease severity between the USA and France, two countries with similar access to hepatitis C virus (HCV) and hepatitis B virus (HBV) treatments, similar rules for treatment reimbursement and similar availability of validated fibrosis tests, but with different policies, as France has no screening. Method The global database of the FibroTest–ActiTest, including 1 085 657 subjects between 2002 and 2014, was retrospectively analysed. Awareness was defined as the test prescription rate and was compared between the USA and France, according to year of birth, gender and dates of DAA availability and screening campaign (2013–2014). Results In the USA 252 688 subjects were investigated for HCV, with a dramatic increase (138%) in the test rate in 2013–2014 (119 271) compared with 2011–2012 (50 031). In France 470 762 subjects were investigated (subjects with HCV and other disease) and the rates were stable. In USA 82.4% of subjects and in France 84.6% were classified as either the highest or lowest priority. The most striking difference was the higher test rate in women born between 1935 and 1944 in France 30 384/200 672 (15.1%) compared with the USA 8035/97 079 (8.3%) (OR=1.98 (95% CI 1.93 to 2.03) p<0.0001). This resulted in twice as many cases of cirrhosis being detected, 2.6% (5191/200 672 women) and 1.3% (1303/97 079), respectively, despite the same prevalence of cirrhosis in this age group (17.1% vs 16.2%) and without any clear explanation as to why they had not been included in the USA screening. Conclusions This study highlighted in the USA the association between awareness of liver disease and both the HCV campaign and

Improving Photovoltaic Performance of a Fused-Ring Azepinedione Copolymer via a D-A-A Design.

PubMed

Zhang, Honghong; Li, Ting; Xiao, Zuo; Lei, Zhongli; Ding, Liming

2018-04-01

Two conjugated copolymer donors, PTTABDT and PBTTABDT, based on a fused-ring azepinedione acceptor unit, 5-(2-octyldodecyl)-4H-thieno[2',3':4,5]thieno[3,2-c]thieno[2',3':4,5]thieno[2,3-e]azepine-4,6(5H)-dione (TTA), are prepared. PTTABDT possesses a conventional donor-acceptor (D-A) structure with one TTA in the repeat unit, while PBTTABDT has a D-A-A structure with two TTAs in the repeat unit. Compared with PTTABDT, PBTTABDT shows a deeper highest occupied molecular orbital (HOMO) level, a narrower bandgap, and a higher hole mobility, and exhibits better performance in bulk heterojunction solar cells. Power conversion efficiencies of 6.18% and 7.81% are achieved from PTTABDT:PC 71 BM and PBTTABDT:PC 71 BM solar cells, respectively. The higher performance of PBTTABDT:PC 71 BM solar cells results from the enhanced open-circuit voltage (V oc ) and short-circuit current density (  J sc ). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Estimating the cascade of hepatitis C testing, care and treatment among people who inject drugs in Australia.

PubMed

Iversen, Jenny; Grebely, Jason; Catlett, Beth; Cunningham, Philip; Dore, Gregory J; Maher, Lisa

2017-09-01

Hepatitis C virus (HCV) infection is endemic among people who inject drugs (PWID) globally. Despite high prevalence, treatment uptake is low, with cumulative uptake <10% in most settings. This study aimed to populate the cascade of HCV testing, care and treatment among PWID using data collected in Australia prior to the introduction of broadly accessible interferon-free direct-acting antiviral (DAA) therapies in March 2016. The Australian Needle and Syringe Program Survey is a cross-sectional surveillance system that recruits ∼2300 PWID annually and collects behavioural data and dried blood samples (DBS). HCV antibody and ribonucleic acid (RNA) test results from DBS collected in 2015 were combined with data on HCV diagnostic testing, care and treatment to populate the HCV cascade among Australian PWID. Among an estimated 93,000 PWID in Australia in 2015, the majority (89%) had a lifetime history of HCV antibody testing. More than half (57%) of PWID tested HCV antibody positive and of these, 79% had detectable HCV RNA consistent with active infection. Less than half (46%) of HCV antibody positive PWID had received confirmatory HCV RNA testing. Among the estimated 43,201 PWID with active infection or chronic infection that had been successfully treated, 31% had received specialist HCV assessment, 8% had received antiviral treatment and 3% were cured. This study provides baseline estimates of the cascade of HCV testing, care and treatment among PWID through enhancement of a well-established surveillance mechanism. Characterisation of the HCV cascade among PWID will be crucial to evaluating and monitoring the roll out of direct-acting antiviral therapies in Australia, including assessing potential HCV treatment as prevention benefits. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of hepatitis C oral therapy in portal hypertension.

PubMed

Libânio, Diogo; Marinho, Rui Tato

2017-07-14

Chronic hepatitis C is a leading cause of morbidity and mortality, mainly related to fibrosis/cirrhosis and portal hypertension. Direct antiviral agents are highly effective and safe and can now cure > 90% of the patients. Sustained viral response (SVR) after interferon-based regimens has been associated with improvement in liver function, fibrosis and portal hypertension in a significant proportion of patients, although a point of no return seems to exist from which viral elimination is no longer capable of preventing portal hypertension progression and liver decompensation. Indeed, although SVR is associated with improvement of hepatic venous pressure gradients and therefore a decreased risk of de novo esophageal varices, several studies show that viral clearance does not eliminate the risk of variceal progression, liver decompensation and death in patients with pre-established portal hypertension. Although evidence about the effects of direct antiviral agents (DAAs) on clinically significant outcomes is still scarce and with short follow-up, DAAs can decrease the burden of the disease if patients are timely treated before significant fibrosis and portal hypertension develops. Studies with longer follow-up are waited to establish the real magnitude of hepatitis C treatment on portal hypertension. Future studies should also focus on predictors of portal hypertension resolution since it can influence management and avoid unnecessary monitoring.

C. elegans ADARs antagonize silencing of cellular dsRNAs by the antiviral RNAi pathway.

PubMed

Reich, Daniel P; Tyc, Katarzyna M; Bass, Brenda L

2018-02-01

Cellular dsRNAs are edited by adenosine deaminases that act on RNA (ADARs). While editing can alter mRNA-coding potential, most editing occurs in noncoding sequences, the function of which is poorly understood. Using dsRNA immunoprecipitation (dsRIP) and RNA sequencing (RNA-seq), we identified 1523 regions of clustered A-to-I editing, termed editing-enriched regions (EERs), in four stages of Caenorhabditis elegans development, often with highest expression in embryos. Analyses of small RNA-seq data revealed 22- to 23-nucleotide (nt) siRNAs, reminiscent of viral siRNAs, that mapped to EERs and were abundant in adr-1;adr-2 mutant animals. Consistent with roles for these siRNAs in silencing, EER-associated genes (EAGs) were down-regulated in adr-1;adr-2 embryos, and this was dependent on associated EERs and the RNAi factor RDE-4. We observed that ADARs genetically interact with the 26G endogenous siRNA (endo-siRNA) pathway, which likely competes for RNAi components; deletion of factors required for this pathway ( rrf-3 or ergo-1 ) in adr-1;adr-2 mutant strains caused a synthetic phenotype that was rescued by deleting antiviral RNAi factors. Poly(A) + RNA-seq revealed EAG down-regulation and antiviral gene induction in adr-1;adr-2;rrf-3 embryos, and these expression changes were dependent on rde-1 and rde-4 Our data suggest that ADARs restrict antiviral silencing of cellular dsRNAs. © 2018 Reich et al.; Published by Cold Spring Harbor Laboratory Press.

Budesonide and Formoterol Reduce Early Innate Anti-Viral Immune Responses In Vitro

PubMed Central

Davies, Janet M.; Carroll, Melanie L.; Li, Hongzhuo; Poh, Alisa M.; Kirkegard, Darren; Towers, Michelle; Upham, John W.

2011-01-01

Asthma is a chronic inflammatory airways disease in which respiratory viral infections frequently trigger exacerbations. Current treatment of asthma with combinations of inhaled corticosteroids and long acting beta2 agonists improves asthma control and reduces exacerbations but what impact this might have on innate anti-viral immunity is unclear. We investigated the in vitro effects of asthma drugs on innate anti-viral immunity. Peripheral blood mononuclear cells (PBMC) from healthy and asthmatic donors were cultured for 24 hours with the Toll-like receptor 7 agonist, imiquimod, or rhinovirus 16 (RV16) in the presence of budesonide and/or formoterol. Production of proinflammatory cytokines and expression of anti-viral intracellular signalling molecules were measured by ELISA and RT-PCR respectively. In PBMC from healthy donors, budesonide alone inhibited IP-10 and IL-6 production induced by imiquimod in a concentration-dependent manner and the degree of inhibition was amplified when budesonide and formoterol were used in combination. Formoterol alone had little effect on these parameters, except at high concentrations (10−6 M) when IL-6 production increased. In RV16 stimulated PBMC, the combination of budesonide and formoterol inhibited IFNα and IP-10 production in asthmatic as well as healthy donors. Combination of budesonide and formoterol also inhibited RV16-stimulated expression of the type I IFN induced genes myxovirus protein A and 2′, 5′ oligoadenylate synthetise. Notably, RV16 stimulated lower levels of type Myxovirus A and oligoadenylate synthase in PBMC of asthmatics than control donors. These in vitro studies demonstrate that combinations of drugs commonly used in asthma therapy inhibit both early pro-inflammatory cytokines and key aspects of the type I IFN pathway. These findings suggest that budesonide and formoterol curtail excessive inflammation induced by rhinovirus infections in patients with asthma, but whether this inhibits viral clearance

A 2,5-Dihydroxybenzoic Acid–Gelatin Conjugate: The Synthesis, Antiviral Activity and Mechanism of Antiviral Action Against Two Alphaherpesviruses

PubMed Central

Lisov, Alexander; Vrublevskaya, Veronika; Lisova, Zoy; Leontievsky, Alexey; Morenkov, Oleg

2015-01-01

Various natural and synthetic polyanionic polymers with different chemical structures are known to exhibit potent antiviral activity in vitro toward a variety of enveloped viruses and may be considered as promising therapeutic agents. A water-soluble conjugate of 2,5-dihydroxybezoic acid (2,5-DHBA) with gelatin was synthesized by laccase-catalyzed oxidation of 2,5-DHBA in the presence of gelatin, and its antiviral activity against pseudorabies virus (PRV) and bovine herpesvirus type 1 (BoHV-1), two members of the Alphaherpesvirinae subfamily, was studied. The conjugate produced no direct cytotoxic effect on cells, and did not inhibit cell growth at concentrations up to 1000 µg/mL. It exhibited potent antiviral activity against PRV (IC50, 1.5–15 µg/mL for different virus strains) and BoHV-1 (IC50, 0.5–0.7 µg/mL). When present during virus adsorption, the conjugate strongly inhibited the attachment of PRV and BoHV-1 to cells. The 2,5-DHBA–gelatin conjugate had no direct virucidal effect on the viruses and did not influence their penetration into cells, cell-to-cell spread, production of infectious virus particles in cells, and expression of PRV glycoproteins E and B. The results indicated that the 2,5-DHBA–gelatin conjugate strongly inhibits the adsorption of alphaherpesviruses to cells and can be a promising synthetic polymer for the development of antiviral formulations against alphaherpesvirus infections. PMID:26501311

Antiviral flavonoids from the seeds of Aesculus chinensis.

PubMed

Wei, Feng; Ma, Shuang-Cheng; Ma, Lin-Yun; But, Paul Pui-Hay; Lin, Rui-Chao; Khan, Ikhlas A

2004-04-01

A bioassay-guided fractionation of an ethanol extract of the seeds of Aesculus chinensis led to the isolation of two new flavanoids (1 and 2), along with eight known ones (3-10). The structures of the new compounds were elucidated by spectroscopic methods including 2D NMR. All compounds were tested for antiviral activity against respiratory syncytial virus (RSV), parainfluenza virus type 3 (PIV 3), and influenza virus type A (Flu A). Compounds 1, 2, and 6 showed significant antiviral activities against RSV with IC(50) values of 4.5, 6.7, and 4.1 microg/mL and selective index (SI) values of 15.8, 32, and 63.8, respectively. Compound 8 demonstrated significant antiviral activity against Flu A with an IC(50) of 24.5 microg/mL and a SI of 16.0, respectively.

An antiviral protein from Bougainvillea spectabilis roots; purification and characterisation.

PubMed

Balasaraswathi, R; Sadasivam, S; Ward, M; Walker, J M

1998-04-01

An antiviral protein active against mechanical transmission of tomato spotted wilt virus was identified in the root tissues of Bougainvillea spectabilis Willd. Bougainvillea Antiviral Protein I (BAP I) was purified to apparent homogeneity from the roots of Bougainvillea by ammonium sulphate precipitation, CM- and DEAE-Sepharose chromatography and reverse phase HPLC. BAP I is a highly basic protein (pI value > 8.6) with an Mr of 28,000. The N-terminal sequence of BAP I showed homology with other plant antiviral proteins. Preliminary tests suggest that purified BAP I is capable of interfering with in vitro protein synthesis.

Niclosamide is a proton carrier and targets acidic endosomes with broad antiviral effects.

PubMed

Jurgeit, Andreas; McDowell, Robert; Moese, Stefan; Meldrum, Eric; Schwendener, Reto; Greber, Urs F

2012-01-01

Viruses use a limited set of host pathways for infection. These pathways represent bona fide antiviral targets with low likelihood of viral resistance. We identified the salicylanilide niclosamide as a broad range antiviral agent targeting acidified endosomes. Niclosamide is approved for human use against helminthic infections, and has anti-neoplastic and antiviral effects. Its mode of action is unknown. Here, we show that niclosamide, which is a weak lipophilic acid inhibited infection with pH-dependent human rhinoviruses (HRV) and influenza virus. Structure-activity studies showed that antiviral efficacy and endolysosomal pH neutralization co-tracked, and acidification of the extracellular medium bypassed the virus entry block. Niclosamide did not affect the vacuolar H(+)-ATPase, but neutralized coated vesicles or synthetic liposomes, indicating a proton carrier mode-of-action independent of any protein target. This report demonstrates that physico-chemical interference with host pathways has broad range antiviral effects, and provides a proof of concept for the development of host-directed antivirals.

Polyacetal Carboxylic Acids: a New Group of Antiviral Polyanions

PubMed Central

Claes, P.; Billiau, A.; De Clercq, E.; Desmyter, J.; Schonne, E.; Vanderhaeghe, H.; De Somer, P.

1970-01-01

Chlorite-oxidized oxypolysaccharides are polyacetal carboxylic acids. They inhibited the cytopathic effect of vesicular stomatitis virus in mouse embryo cell cultures challenged at low input multiplicity. After intraperitoneal injection of these compounds in mice, interferon appeared in the circulation. The compounds also protected mice against lethal mengovirus infection and against the development of experimental pox lesions on the tail. Chlorite-oxidized oxyamylose was antiviral only when at least 64% of the glucopyranose units were oxidized, an observation which suggested a correlation between charge density and antiviral effect. The antiviral activity was also influenced by the molecular weight, as demonstrated by the fact that chlorite-oxidized dextrans which had a high intrinsic viscosity were more active than those with low intrinsic viscosity. PMID:4314553

Antiviral agents for infectious mononucleosis (glandular fever).

PubMed

De Paor, Muireann; O'Brien, Kirsty; Fahey, Tom; Smith, Susan M

2016-12-08

Infectious mononucleosis (IM) is a clinical syndrome, usually caused by the Epstein Barr virus (EPV), characterised by lymphadenopathy, fever and sore throat. Most cases of symptomatic IM occur in older teenagers or young adults. Usually IM is a benign self-limiting illness and requires only symptomatic treatment. However, occasionally the disease course can be complicated or prolonged and lead to decreased productivity in terms of school or work. Antiviral medications have been used to treat IM, but the use of antivirals for IM is controversial. They may be effective by preventing viral replication which helps to keep the virus inactive. However, there are no guidelines for antivirals in IM. To assess the effects of antiviral therapy for infectious mononucleosis (IM). We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 3, March 2016), which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register, MEDLINE (1946 to 15 April 2016), Embase (1974 to 15 April 2016), CINAHL (1981 to 15 April 2016), LILACS (1982 to 15 April 2016) and Web of Science (1955 to 15 April 2016). We searched the World Health Organization (WHO) International Clinical Trials Registry Platform and ClinicalTrials.gov for completed and ongoing trials. We included randomised controlled trials (RCTs) comparing antivirals versus placebo or no treatment in IM. We included trials of immunocompetent participants of any age or sex with clinical and laboratory-confirmed diagnosis of IM, who had symptoms for up to 14 days. Our primary outcomes were time to clinical recovery and adverse events and side effects of medication. Secondary outcomes included duration of abnormal clinical examination, complications, viral shedding, health-related quality of life, days missing from school or work and economic outcomes. Two review authors independently assessed studies for inclusion, assessed the included studies' risk of bias and extracted data using a

Exposure-Response Relationship for Ombitasvir and Paritaprevir/Ritonavir in Hepatitis C Virus Subgenotype 1b-Infected Japanese Patients in the Phase 3 Randomized GIFT-I Study.

PubMed

Gopalakrishnan, Sathej; Khatri, Amit; Mensing, Sven; Redman, Rebecca; Menon, Rajeev; Zha, Jiuhong

2016-04-01

The all-oral 2 direct-acting antiviral (DAA) regimen of ombitasvir/paritaprevir/ritonavir 25/150/100 mg once a day has been evaluated in hepatitis C virus subgenotype 1b-infected Japanese adults in the GIFT-I study. The aim of this analysis was to evaluate potential relationships between DAA exposures and laboratory abnormalities/adverse events of peripheral edema in patients in GIFT-I. The GIFT-I study consisted of a randomized, double-blind, placebo-controlled substudy in patients without cirrhosis and an open-label substudy in patients with compensated cirrhosis. Patients received ombitasvir/paritaprevir/ritonavir for 12 weeks. Exposure-response relationships between individual components of the ombitasvir/paritaprevir/ritonavir regimen and clinical parameters of interest were explored using pharmacokinetic and clinical data from patients in the study. Graphical analyses were performed. For events that occurred in at least 10 patients (total bilirubin elevation ≥grade 2 and peripheral edema ≥grade 1), multivariate logistic regression analyses were used to identify significant relationships between predictor variables (drug exposures) and response variables (probability of adverse events or laboratory abnormalities), with consideration for the effect of potential covariates and baseline status of response variables. Data from 321 noncirrhotic and 42 compensated cirrhotic patients were analyzed. There were 14 events of peripheral edema (10 at grade 1 and 4 at grade 2) in patients who received concomitant administration of calcium channel blockers and ombitasvir/paritaprevir/ritonavir. There was no apparent relationship between the incidences of peripheral edema and exposures of paritaprevir, ombitasvir, or ritonavir. There was a shallow relationship between total bilirubin elevation and exposures of paritaprevir which is an inhibitor of bilirubin transporter organic anion-transporting polypeptide 1B. Based on graphical analyses, exposures of paritaprevir

Prevalence of HCV Infection in Adults with Congenital Heart Disease and Treatment with Direct Antiviral Agents.

PubMed

Gade, Ajay Reddy; Patel, Manisha; West, Donna R; Abrams, Gary A

2018-03-01

Hepatitis C virus (HCV) infection affects >3% of the US population, which over time can lead to cirrhosis and hepatocellular carcinoma. The lack of a reliable screening method for HCV before 1992 resulted in a higher prevalence of the virus in adults with congenital heart disease who underwent corrective surgery that required blood transfusions. Direct-acting antiviral agents such as sofosbuvir/ledipasvir have significantly increased the efficacy of HCV therapy, although use of these medications in adults with congenital heart disease has not been described. Ours was a retrospective study of 188 adults with congenital heart conditions who had cardiac surgery before 1992. These patients were screened for HCV using HCV antibody followed by HCV RNA if the screening test was positive. Of the 188 adults, 116 (43% male patients, 24-70 years) were screened for the HCV antibody, demonstrating that 104 individuals were negative and 12 subjects were positive for the virus. Subsequently, further testing for the presence of HCV demonstrated 11 of 12 were infected, with an overall prevalence of 9.5%. Five individuals chose to be treated with sofosbuvir/ledipasvir and 5 of 5 have successfully cleared the virus and are considered cured. Adults with congenital heart disease who underwent cardiac surgery before 1992 warrant being screened for HCV, and, if testing positive, may be considered for therapy using direct-acting antiviral agents with close monitoring for cardiac complications.

Approved Antiviral Drugs over the Past 50 Years

PubMed Central

2016-01-01

SUMMARY Since the first antiviral drug, idoxuridine, was approved in 1963, 90 antiviral drugs categorized into 13 functional groups have been formally approved for the treatment of the following 9 human infectious diseases: (i) HIV infections (protease inhibitors, integrase inhibitors, entry inhibitors, nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors, and acyclic nucleoside phosphonate analogues), (ii) hepatitis B virus (HBV) infections (lamivudine, interferons, nucleoside analogues, and acyclic nucleoside phosphonate analogues), (iii) hepatitis C virus (HCV) infections (ribavirin, interferons, NS3/4A protease inhibitors, NS5A inhibitors, and NS5B polymerase inhibitors), (iv) herpesvirus infections (5-substituted 2′-deoxyuridine analogues, entry inhibitors, nucleoside analogues, pyrophosphate analogues, and acyclic guanosine analogues), (v) influenza virus infections (ribavirin, matrix 2 protein inhibitors, RNA polymerase inhibitors, and neuraminidase inhibitors), (vi) human cytomegalovirus infections (acyclic guanosine analogues, acyclic nucleoside phosphonate analogues, pyrophosphate analogues, and oligonucleotides), (vii) varicella-zoster virus infections (acyclic guanosine analogues, nucleoside analogues, 5-substituted 2′-deoxyuridine analogues, and antibodies), (viii) respiratory syncytial virus infections (ribavirin and antibodies), and (ix) external anogenital warts caused by human papillomavirus infections (imiquimod, sinecatechins, and podofilox). Here, we present for the first time a comprehensive overview of antiviral drugs approved over the past 50 years, shedding light on the development of effective antiviral treatments against current and emerging infectious diseases worldwide. PMID:27281742

Glycodendritic structures: promising new antiviral drugs.

PubMed

Rojo, Javier; Delgado, Rafael

2004-09-01

DC-SIGN, a C-type lectin expressed by dendritic cells, is able to recognize high mannosylated glycoproteins at the surface of a broad range of pathogens including viruses, bacteria, fungi and parasites. For at least some of these agents this interaction appears to be an important part of the infection process. Therefore, this lectin might be considered in the design of new antiviral drugs. In this manner, multivalent carbohydrate systems based on dendrimers and dendritic polymers are promising candidates as antiviral drugs. Boltorn hyperbranched dendritic polymers functionalized with mannose have been used to inhibit DC-SIGN-mediated infection in an Ebola-pseudotyped viral model. Their physiological solubility, lack of toxicity and especially their low price suggest the application of these glycodendritic polymers for possible formulation as microbicides.

Antiviral effect of emodin from Rheum palmatum against coxsakievirus B5 and human respiratory syncytial virus in vitro.

PubMed

Liu, Zhao; Ma, Nian; Zhong, Yan; Yang, Zhan-qiu

2015-12-01

Viral infections are the major causes of morbidity and mortality in elderly people and young children throughout the world. The most common pathogens include coxsackie virus (CV) and respiratory syncytial virus (RSV). However, no antiviral agents with low toxicity and drug resistance are currently available in clinic therapy. The present study aimed to examine the antiviral activities of emodin (an ingredient of Rheum palmatum) against CVB5 and RSV infections, in an attempt to discover new antiviral agents for virus infection. The monomer emodin was extracted and isolated from Rheum palmatum. The antiviral activities of emodin on HEp-2 cells were evaluated, including virus replication inhibition, virucidal and anti-absorption effects, by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tet-razolium bromide (MTT) assay and plaque reduction assay (PRA). The kinetics of virus inhibition by emodin in a period of 14 h was further determined by plaque assay and quantitative real time PCR (qPCR). Cytokine (IFN-γ, TNF-α) mRNA expressions after emodin treatment (7.5, 15, 30 μmol/L) were also assessed by qPCR post-infection. The results showed that emodin had potent inhibitory activities against CVB5 and RSV, with the 50% effective concentration (EC50) ranging from 13.06 to 14.27 μmol/L and selectivity index (SI) being 5.38-6.41 μmol/L. However, emodin couldn't directly inactivate the viruses or block their absorption to cells. It acted as a biological synthesis inhibitor against CVB4 and RSV in a concentration- and time-dependent manner, especially during the first 0-4 h post-infection. Moreover, emodin could decrease the mRNA expression of IFN-α but enhance TNF-γ expression significantly compared to the viral controls in vitro. Our results provide a molecular basis for development of emodin as a novel and safe antiviral agent for human enterovirus and respiratory virus infection in the clinical therapy.

Chemical Space Mapping and Structure-Activity Analysis of the ChEMBL Antiviral Compound Set.

PubMed

Klimenko, Kyrylo; Marcou, Gilles; Horvath, Dragos; Varnek, Alexandre

2016-08-22

Curation, standardization and data fusion of the antiviral information present in the ChEMBL public database led to the definition of a robust data set, providing an association of antiviral compounds to seven broadly defined antiviral activity classes. Generative topographic mapping (GTM) subjected to evolutionary tuning was then used to produce maps of the antiviral chemical space, providing an optimal separation of compound families associated with the different antiviral classes. The ability to pinpoint the specific spots occupied (responsibility patterns) on a map by various classes of antiviral compounds opened the way for a GTM-supported search for privileged structural motifs, typical for each antiviral class. The privileged locations of antiviral classes were analyzed in order to highlight underlying privileged common structural motifs. Unlike in classical medicinal chemistry, where privileged structures are, almost always, predefined scaffolds, privileged structural motif detection based on GTM responsibility patterns has the decisive advantage of being able to automatically capture the nature ("resolution detail"-scaffold, detailed substructure, pharmacophore pattern, etc.) of the relevant structural motifs. Responsibility patterns were found to represent underlying structural motifs of various natures-from very fuzzy (groups of various "interchangeable" similar scaffolds), to the classical scenario in medicinal chemistry (underlying motif actually being the scaffold), to very precisely defined motifs (specifically substituted scaffolds).

Mechanisms, applications, and perspectives of antiviral RNA silencing in plants

PubMed Central

Garcia-Ruiz, Hernan; Ruiz, Mayra Teresa Garcia; Peralta, Sergio Manuel Gabriel; Gabriel, Cristina Betzabeth Miravel; El-Mounadi, Kautar

2017-01-01

Viral diseases of plants cause important economic losses due to reduction in crop quality and quantity to the point of threatening food security in some countries. Given the reduced availability of natural sources, genetic resistance to viruses has been successfully engineered for some plant-virus combinations. A sound understanding of the basic mechanisms governing plant-virus interactions, including antiviral RNA silencing, is the foundation to design better management strategies and biotechnological approaches to engineer and implement antiviral resistance in plants. In this review, we present current molecular models to explain antiviral RNA silencing and its application in basic plant research, biotechnology and genetic engineering. PMID:28890589

Treatment as Prevention for Hepatitis C (TraP Hep C) - a nationwide elimination programme in Iceland using direct-acting antiviral agents.

PubMed

Olafsson, S; Tyrfingsson, T; Runarsdottir, V; Bergmann, O M; Hansdottir, I; Björnsson, E S; Johannsson, B; Sigurdardottir, B; Fridriksdottir, R H; Löve, A; Hellard, M; Löve, T J; Gudnason, T; Heimisdottir, M; Gottfredsson, M

2018-05-01

A nationwide programme for the treatment of all patients infected with hepatitis C virus (HCV) was launched in Iceland in January 2016. By providing universal access to direct-acting antiviral agents to the entire patient population, the two key aims of the project were to (i) offer a cure to patients and thus reduce the long-term sequelae of chronic hepatitis C, and (ii) to reduce domestic incidence of HCV in the population by 80% prior to the WHO goal of HCV elimination by the year 2030. An important part of the programme is that vast majority of cases will be treated within 36 months from the launch of the project, during 2016-2018. Emphasis is placed on early case finding and treatment of patients at high risk for transmitting HCV, that is people who inject drugs (PWID), as well as patients with advanced liver disease. In addition to treatment scale-up, the project also entails intensification of harm reduction efforts, improved access to diagnostic tests, as well as educational campaigns to curtail spread, facilitate early detection and improve linkage to care. With these efforts, Iceland is anticipated to achieve the WHO hepatitis C elimination goals well before 2030. This article describes the background and organization of this project. Clinical trial number: NCT02647879. © 2018 The Authors. Journal of Internal Medicine published by John Wiley & Sons Ltd on behalf of Association for Publication of The Journal of Internal Medicine.

Screening for Antiviral Activities of Isolated Compounds from Essential Oils

PubMed Central

Astani, Akram; Reichling, Jürgen; Schnitzler, Paul

2011-01-01

Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1) in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60–80% and sesquiterpenes suppressed herpes virus infection by 40–98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV. PMID:20008902

Mst1 shuts off cytosolic antiviral defense through IRF3 phosphorylation

PubMed Central

Meng, Fansen; Zhou, Ruyuan; Wu, Shiying; Zhang, Qian; Jin, Qiuheng; Zhou, Yao; Plouffe, Steven W.; Liu, Shengduo; Song, Hai; Xia, Zongping; Zhao, Bin; Ye, Sheng; Feng, Xin-Hua; Guan, Kun-Liang; Zou, Jian

2016-01-01

Cytosolic RNA/DNA sensing elicits primary defense against viral pathogens. Interferon regulatory factor 3 (IRF3), a key signal mediator/transcriptional factor of the antiviral-sensing pathway, is indispensible for interferon production and antiviral defense. However, how the status of IRF3 activation is controlled remains elusive. Through a functional screen of the human kinome, we found that mammalian sterile 20-like kinase 1 (Mst1), but not Mst2, profoundly inhibited cytosolic nucleic acid sensing. Mst1 associated with IRF3 and directly phosphorylated IRF3 at Thr75 and Thr253. This Mst1-mediated phosphorylation abolished activated IRF3 homodimerization, its occupancy on chromatin, and subsequent IRF3-mediated transcriptional responses. In addition, Mst1 also impeded virus-induced activation of TANK-binding kinase 1 (TBK1), further attenuating IRF3 activation. As a result, Mst1 depletion or ablation enabled an enhanced antiviral response and defense in cells and mice. Therefore, the identification of Mst1 as a novel physiological negative regulator of IRF3 activation provides mechanistic insights into innate antiviral defense and potential antiviral prevention strategies. PMID:27125670

Steroid plus antiviral treatment for Bell's palsy.

PubMed

Kang, H M; Jung, S Y; Byun, J Y; Park, M S; Yeo, S G

2015-05-01

The effectiveness of antiviral agents for the treatment of Bell's palsy is uncertain. We evaluated whether a steroid with an antiviral agent (S + A group) provided better recovery outcomes than a steroid alone (S group) in patients with Bell's palsy. A total of 1342 patients diagnosed with Bell's palsy who visited the Kyung Hee Medical Center in Seoul, Korea, from 2002 to 2012 were included in this study. Patients in the S + A group were treated with prednisolone and antiviral agents (n = 569) and those in the S group with prednisolone alone (n = 773). Outcomes were measured using the House-Brackmann (HB) scale according to age, initial disease severity, electroneurography (ENoG) findings and underlying comorbidities. The rate of recovery (HB grades I and II) with initially severe Bell's palsy (HB grades V and VI) was higher in the S + A than in the S group (P = 0.001). However, the rates of recovery were similar with initially moderate palsy (HB grades II-IV) (P = 0.502). In patients classified according to age and ENoG-determined severity of palsy, the overall recovery rate was higher in the S + A than in the S group, but the differences were not statistically significant (P > 0.05 for both). The recovery rate without diabetes mellitus (DM) and hypertension (HTN) was higher in the S + A group than in the S group (P = 0.031). But in the patients with HTN and DM, the difference in recovery rates between the S + A and S groups was not statistically significant (P = 0.805). Treatment with a steroid plus antiviral agent resulted in significantly higher recovery rates than steroid therapy alone in patients with initially severe Bell's palsy and without either HTN or DM, and a nonsignificant trend towards higher recovery rates in all patients with Bell's palsy in this study. Antiviral agents may therefore help in the treatment of Bell's palsy. © 2014 The Association for the Publication of the Journal of Internal Medicine.

CRM1 Inhibitors for Antiviral Therapy

PubMed Central

Mathew, Cynthia; Ghildyal, Reena

2017-01-01

Infectious diseases are a major global concern and despite major advancements in medical research, still cause significant morbidity and mortality. Progress in antiviral therapy is particularly hindered by appearance of mutants capable of overcoming the effects of drugs targeting viral components. Alternatively, development of drugs targeting host proteins essential for completion of viral lifecycle holds potential as a viable strategy for antiviral therapy. Nucleocytoplasmic trafficking pathways in particular are involved in several pathological conditions including cancer and viral infections, where hijacking or alteration of function of key transporter proteins, such as Chromosome Region Maintenance1 (CRM1) is observed. Overexpression of CRM1-mediated nuclear export is evident in several solid and hematological malignancies. Interestingly, CRM1-mediated nuclear export of viral components is crucial in various stages of the viral lifecycle and assembly. This review summarizes the role of CRM1 in cancer and selected viruses. Leptomycin B (LMB) is the prototypical inhibitor of CRM1 potent against various cancer cell lines overexpressing CRM1 and in limiting viral infections at nanomolar concentrations in vitro. However, the irreversible shutdown of nuclear export results in high cytotoxicity and limited efficacy in vivo. This has prompted search for synthetic and natural CRM1 inhibitors that can potentially be developed as broadly active antivirals, some of which are summarized in this review. PMID:28702009

Antiviral activity of silver nanoparticle/chitosan composites against H1N1 influenza A virus

NASA Astrophysics Data System (ADS)

Mori, Yasutaka; Ono, Takeshi; Miyahira, Yasushi; Nguyen, Vinh Quang; Matsui, Takemi; Ishihara, Masayuki

2013-02-01

Silver nanoparticle (Ag NP)/chitosan (Ch) composites with antiviral activity against H1N1 influenza A virus were prepared. The Ag NP/Ch composites were obtained as yellow or brown floc-like powders following reaction at room temperature in aqueous medium. Ag NPs (3.5, 6.5, and 12.9 nm average diameters) were embedded into the chitosan matrix without aggregation or size alternation. The antiviral activity of the Ag NP/Ch composites was evaluated by comparing the TCID50 ratio of viral suspensions treated with the composites to untreated suspensions. For all sizes of Ag NPs tested, antiviral activity against H1N1 influenza A virus increased as the concentration of Ag NPs increased; chitosan alone exhibited no antiviral activity. Size dependence of the Ag NPs on antiviral activity was also observed: antiviral activity was generally stronger with smaller Ag NPs in the composites. These results indicate that Ag NP/Ch composites interacting with viruses exhibit antiviral activity.

Cytotoxicity and antiviral activity of methanol extract from Polygonum minus

NASA Astrophysics Data System (ADS)

Wahab, Noor Zarina Abd; Bunawan, Hamidun; Ibrahim, Nazlina

2015-09-01

A study was carried out to test the cytotoxicity and antiviral effects of methanolic extracts from the leaves and stem of Polygonum minus or kesum. Cytotoxicity tests were performed on Vero cells indicates the LC50 value for leaf extract towards the Vero cells was 875 mg/L and the LC50 value for stem extract was 95 mg/L. The LC50 values indidcate the non-cytotoxic effect of the extracts and worth for further testing. Antiviral test were carried out towards herpes simplex virus infected Vero cells using three concentration of extract which were equivalent to 1.0 LC50, 0.1 LC50 and 0.01 LC50. Three different treatments to detect antiviral activity were used. Mild antiviral activity of the stem extract was detected when cells were treated for 24 hours with plant extract before viral infection. This demonstrates the capability of the test compound to protect the cells from viral attachment and of the possible prophylactic effect of the P. minus stem methanol extract.

Cellular Antiviral Factors that Target Particle Infectivity of HIV-1.

PubMed

Goffinet, Christine

2016-01-01

In the past decade, the identification and characterization of antiviral genes with the ability to interfere with virus replication has established cell-intrinsic innate immunity as a third line of antiviral defense in addition to adaptive and classical innate immunity. Understanding how cellular factors have evolved to inhibit HIV-1 reveals particularly vulnerable points of the viral replication cycle. Many, but not all, antiviral proteins share type I interferon-upregulated expression and sensitivity to viral counteraction or evasion measures. Whereas well-established restriction factors interfere with early post-entry steps and release of HIV-1, recent research has revealed a diverse set of proteins that reduce the infectious quality of released particles using individual, to date poorly understood modes of action. These include induction of paucity of mature glycoproteins in nascent virions or self-incorporation into the virus particle, resulting in poor infectiousness of the virion and impaired spread of the infection. A better understanding of these newly discovered antiviral factors may open new avenues towards the design of drugs that repress the spread of viruses whose genomes have already integrated.

Discovery of Multitarget Agents Active as Broad-Spectrum Antivirals and Correctors of Cystic Fibrosis Transmembrane Conductance Regulator for Associated Pulmonary Diseases.

PubMed

Tassini, Sabrina; Sun, Liang; Lanko, Kristina; Crespan, Emmanuele; Langron, Emily; Falchi, Federico; Kissova, Miroslava; Armijos-Rivera, Jorge I; Delang, Leen; Mirabelli, Carmen; Neyts, Johan; Pieroni, Marco; Cavalli, Andrea; Costantino, Gabriele; Maga, Giovanni; Vergani, Paola; Leyssen, Pieter; Radi, Marco

2017-02-23

Enteroviruses (EVs) are among the most frequent infectious agents in humans worldwide and represent the leading cause of upper respiratory tract infections. No drugs for the treatment of EV infections are currently available. Recent studies have also linked EV infection with pulmonary exacerbations, especially in cystic fibrosis (CF) patients, and the importance of this link is probably underestimated. The aim of this work was to develop a new class of multitarget agents active both as broad-spectrum antivirals and as correctors of the F508del-cystic fibrosis transmembrane conductance regulator (CFTR) folding defect responsible for >90% of CF cases. We report herein the discovery of the first small molecules able to simultaneously act as correctors of the F508del-CFTR folding defect and as broad-spectrum antivirals against a panel of EVs representative of all major species.

Antiviral effect of lithium chloride on infection of cells by canine parvovirus.

PubMed

Zhou, Pei; Fu, Xinliang; Yan, Zhongshan; Fang, Bo; Huang, San; Fu, Cheng; Hong, Malin; Li, Shoujun

2015-11-01

Canine parvovirus type 2 causes significant viral disease in dogs, with high morbidity, high infectivity, and high mortality. Lithium chloride is a potential antiviral drug for viruses. We determined the antiviral effect of Lithium Chloride on canine parvovirus type 2 in feline kidney cells. The viral DNA and proteins of canine parvovirus were suppressed in a dose-dependent manner by lithium chloride. Further investigation verified that viral entry into cells was inhibited in a dose-dependent manner by lithium chloride. These results indicated that lithium chloride could be a potential antiviral drug for curing dogs with canine parvovirus infection. The specific steps of canine parvovirus entry into cells that are affected by lithium chloride and its antiviral effect in vivo should be explored in future studies.

Induced antiviral innate immunity in Drosophila.

PubMed

Lamiable, Olivier; Imler, Jean-Luc

2014-08-01

Immunity to viral infections in the model organism Drosophila melanogaster involves both RNA interference and additional induced responses. The latter include not only cellular mechanisms such as programmed cell death and autophagy, but also the induction of a large set of genes, some of which contribute to the control of viral replication and resistance to infection. This induced response to infection is complex and involves both virus-specific and cell-type specific mechanisms. We review here recent developments, from the sensing of viral infection to the induction of signaling pathways and production of antiviral effector molecules. Our current understanding, although still partial, validates the Drosophila model of antiviral induced immunity for insect pests and disease vectors, as well as for mammals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antiviral Potential of Algae Polysaccharides Isolated from Marine Sources: A Review.

PubMed

Ahmadi, Azin; Zorofchian Moghadamtousi, Soheil; Abubakar, Sazaly; Zandi, Keivan

2015-01-01

From food to fertilizer, algal derived products are largely employed in assorted industries, including agricultural, biomedical, food, and pharmaceutical industries. Among different chemical compositions isolated from algae, polysaccharides are the most well-established compounds, which were subjected to a variety of studies due to extensive bioactivities. Over the past few decades, the promising results for antiviral potential of algae-derived polysaccharides have advocated them as inordinate candidates for pharmaceutical research. Numerous studies have isolated various algal polysaccharides possessing antiviral activities, including carrageenan, alginate, fucan, laminaran, and naviculan. In addition, different mechanisms of action have been reported for these polysaccharides, such as inhibiting the binding or internalization of virus into the host cells or suppressing DNA replication and protein synthesis. This review strives for compiling previous antiviral studies of algae-derived polysaccharides and their mechanism of action towards their development as natural antiviral agents for future investigations.

76 FR 28991 - Privacy Act of 1974; Report of a New System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-19

... pandemic 2009 H1N1 influenza vaccines, antiviral medications (e.g., Tamiflu), anthrax vaccines, and smallpox vaccines. The PREP Act directs the Secretary to establish administrative procedures to compensate... resulting from pandemic, epidemic, or security countermeasures such as vaccines identified in declarations...

Recent advances in the treatment of hepatitis C.

PubMed

Dhingra, Abhinav; Kapoor, Saloni; Alqahtani, Saleh A

2014-10-01

Hepatitis C virus (HCV) therapeutics is amidst a revolution. With the recent approval of sofosbuvir (Sovaldi) and simeprevir (Olysio), clinicians and patients started to recognize that for the first time in the history, hepatitis C can be cured in a majority of patients without interferon. These new regimens are safe, and have excellent efficacy and minimal adverse events. Sofosbuvir, a nucleotide analogue (NS5B polymerase inhibitor), is a potent drug with excellent tolerability and pan-genotypic activity with a high barrier to resistance. Simeprevir, a second-generation protease inhibitor which inhibits the initial cleavage of the HCV poly-protein by the NS3/4A protease. Simeprevir has been evaluated in clinical trials in combination with interferon and ribavirin based therapy and also in the COSMO trial in combination with sofosbuvir. More directly acting antiviral therapy drugs are in the pipeline with several drugs being expected to be approved by the FDA in late 2014. Although these drugs have excellent efficacy, they are more costly. The price of these drugs limits treatments of many patients in the world especially in countries with limited economic resources. However, with the availability of a variety of excellent directly acting antivirals (DAAs) in the near future, hopefully many patients would be able to afford the treatment. The future in HCV therapy will focus on special groups of patients who were excluded from initial HCV clinical trials such as post-liver transplant HCV recurrence, patients with HCV/HIV co-infection, and patients with advanced cirrhosis.

RNA interference-mediated intrinsic antiviral immunity in invertebrates.

PubMed

Nayak, Arabinda; Tassetto, Michel; Kunitomi, Mark; Andino, Raul

2013-01-01

In invertebrates such as insects and nematodes, RNA interference (RNAi) provides RNA-based protection against viruses. This form of immunity restricts viral replication and dissemination from infected cells and viruses, in turn, have evolved evasion mechanisms or RNAi suppressors to counteract host defenses. Recent advances indicate that, in addition to RNAi, other related small RNA pathways contribute to antiviral functions in invertebrates. This has led to a deeper understanding of fundamental aspects of small RNA-based antiviral immunity in invertebrates and its contribution to viral spread and pathogenesis.

Antiviral and cytotoxic activities of some Indonesian plants.

PubMed

Lohézic-Le Dévéhat, F; Bakhtiar, A; Bézivin, C; Amoros, M; Boustie, J

2002-08-01

Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.

Genome-Wide RNAi Screen Identifies Broadly-Acting Host Factors That Inhibit Arbovirus Infection

PubMed Central

Yasunaga, Ari; Hanna, Sheri L.; Li, Jianqing; Cho, Hyelim; Rose, Patrick P.; Spiridigliozzi, Anna; Gold, Beth; Diamond, Michael S.; Cherry, Sara

2014-01-01

Vector-borne viruses are an important class of emerging and re-emerging pathogens; thus, an improved understanding of the cellular factors that modulate infection in their respective vertebrate and insect hosts may aid control efforts. In particular, cell-intrinsic antiviral pathways restrict vector-borne viruses including the type I interferon response in vertebrates and the RNA interference (RNAi) pathway in insects. However, it is likely that additional cell-intrinsic mechanisms exist to limit these viruses. Since insects rely on innate immune mechanisms to inhibit virus infections, we used Drosophila as a model insect to identify cellular factors that restrict West Nile virus (WNV), a flavivirus with a broad and expanding geographical host range. Our genome-wide RNAi screen identified 50 genes that inhibited WNV infection. Further screening revealed that 17 of these genes were antiviral against additional flaviviruses, and seven of these were antiviral against other vector-borne viruses, expanding our knowledge of invertebrate cell-intrinsic immunity. Investigation of two newly identified factors that restrict diverse viruses, dXPO1 and dRUVBL1, in the Tip60 complex, demonstrated they contributed to antiviral defense at the organismal level in adult flies, in mosquito cells, and in mammalian cells. These data suggest the existence of broadly acting and functionally conserved antiviral genes and pathways that restrict virus infections in evolutionarily divergent hosts. PMID:24550726

Using the Ferret as an Animal Model for Investigating Influenza Antiviral Effectiveness

PubMed Central

Oh, Ding Y.; Hurt, Aeron C.

2016-01-01

The concern of the emergence of a pandemic influenza virus has sparked an increased effort toward the development and testing of novel influenza antivirals. Central to this is the animal model of influenza infection, which has played an important role in understanding treatment effectiveness and the effect of antivirals on host immune responses. Among the different animal models of influenza, ferrets can be considered the most suitable for antiviral studies as they display most of the human-like symptoms following influenza infections, they can be infected with human influenza virus without prior viral adaptation and have the ability to transmit influenza virus efficiently between one another. However, an accurate assessment of the effectiveness of an antiviral treatment in ferrets is dependent on three major experimental considerations encompassing firstly, the volume and titer of virus, and the route of viral inoculation. Secondly, the route and dose of drug administration, and lastly, the different methods used to assess clinical symptoms, viral shedding kinetics and host immune responses in the ferrets. A good understanding of these areas is necessary to achieve data that can accurately inform the human use of influenza antivirals. In this review, we discuss the current progress and the challenges faced in these three major areas when using the ferret model to measure influenza antiviral effectiveness. PMID:26870031

Micro-costing analysis of guideline-based treatment by direct-acting agents: the real-life case of hepatitis C management in Brazil.

PubMed

Perazzo, Hugo; Jorge, Marcelino Jose; Silva, Julio Castro; Avellar, Alexandre Monken; Silva, Patrícia Santos; Romero, Carmen; Veloso, Valdilea Gonçalves; Mujica-Mota, Ruben; Anderson, Rob; Hyde, Chris; Castro, Rodolfo

2017-11-23

Eradication of hepatitis C virus (HCV) using direct-acting agents (DAA) has been associated with a financial burden to health authorities worldwide. We aimed to evaluate the guideline-based treatment costs by DAAs from the perspective of the Brazilian Ministry of Health (BMoH). The activity based costing method was used to estimate the cost for monitoring/treatment of genotype-1 (GT1) HCV patients by the following strategies: peg-interferon (PEG-IFN)/ribavirin (RBV) for 48 weeks, PEG-IFN/RBV plus boceprevir (BOC) or telaprevir (TEL) for 48 weeks, and sofosbuvir (SOF) plus daclastavir (DCV) or simeprevir (SIM) for 12 weeks. Costs were reported in United States Dollars without (US$) and with adjustment for purchasing power parity (PPP$). Drug costs were collected at the National Database of Health Prices and an overview of the literature was performed to assess effectiveness of SOF/DCV and SOF/SIM regimens in real-world cohorts. Treatment costs of GT1-HCV patients were PPP$ 43,176.28 (US$ 24,020.16) for PEG-IFN/RBV, PPP$ 71,196.03 (US$ 39,578.23) for PEG-IFN/RBV/BOC and PPP$ 86,250.33 (US$ 47,946.92) for PEG-IFN/RBV/TEL. Treatment by all-oral interferon-free regimens were the less expensive approach: PPP$ 19,761.72 (US$ 10,985.90) for SOF/DCV and PPP$ 21,590.91 (US$ 12,002.75) for SOF/SIM. The overview reported HCV eradication in up to 98% for SOF/DCV and 96% for SOF/SIM. Strategies with all oral interferon-free might lead to lower costs for management of GT1-HCV patients compared to IFN-based regimens in Brazil. This occurred mainly because of high discounts over international DAA prices due to negotiation between BMoH and pharmaceutical industries.

LGP2 Synergy with MDA5 in RLR-Mediated RNA Recognition and Antiviral Signaling

PubMed Central

Bruns, Annie M.; Horvath, Curt M.

2015-01-01

Mammalian cells have the ability to recognize virus infection and mount a powerful antiviral response. Pattern recognition receptor proteins detect molecular signatures of virus infection and activate antiviral signaling. The RIG-I-like receptor (RLR) proteins are expressed in the cytoplasm of nearly all cells and specifically recognize virus-derived RNA species as a molecular feature discriminating the pathogen from the host. The RLR family is composed of three homologous proteins, RIG-I, MDA5, and LGP2. All RLRs have the ability to detect virus-derived dsRNA and hydrolyze ATP, but display individual differences in enzymatic activity, intrinsic ability to recognize RNA, and mechanisms of activation. Emerging evidence suggests that MDA5 and RIG-I utilize distinct mechanisms to form oligomeric complexes along dsRNA. Aligning of their signaling domains creates a platform capable of propagating and amplifying antiviral signaling responses. LGP2 with intact ATP hydrolysis is critical for the MDA5-mediated antiviral response, but LGP2 lacks the domains essential for activation of antiviral signaling, leaving the role of LGP2 in antiviral signaling unclear. Recent studies revealed a mechanistic basis of synergy between LGP2 and MDA5 leading to enhanced antiviral signaling. This review briefly summarizes the RLR system, and focuses on the relationship between LGP2 and MDA5, describing in detail how these two proteins work together to detect foreign RNA and generate a fully functional antiviral response. PMID:25794939

Antiviral effect of diammonium glycyrrhizinate on cell infection by porcine parvovirus

USDA-ARS?s Scientific Manuscript database

Porcine parvovirus (PPV) can cause reproductive failure in swine resulting in economic losses to the industry. Antiviral effects of diammonium glycyrrhizinate (DG) have been reported on several animal viruses; however, to date it has yet to be tested on PPV. In this study, the antiviral activity of ...

Antiviral activity of some South American medicinal plants.

PubMed

Abad, M J; Bermejo, P; Sanchez Palomino, S; Chiriboga, X; Carrasco, L

1999-03-01

Folk medicinal plants are potential sources of useful therapeutic compounds including some with antiviral activities. Extracts prepared from 10 South American medicinal plants (Baccharis trinervis, Baccharis teindalensis, Eupatorium articulatum, Eupatorium glutinosum, Tagetes pusilla, Neurolaena lobata, Conyza floribunda, Phytolacca bogotensis, Phytolacca rivinoides and Heisteria acuminata) were screened for in vitro antiviral activity against herpes simplex type I (HSV-1), vesicular stomatitis virus (VSV) and poliovirus type 1. The most potent inhibition was observed with an aqueous extract of B. trinervis, which inhibited HSV-1 replication by 100% at 50-200 micrograms/mL, without showing cytotoxic effects. Good activities were also found with the ethanol extract of H. acuminata and the aqueous extract of E. articulatum, which exhibited antiviral effects against both DNA and RNA viruses (HSV-1 and VSV, respectively) at 125-250 micrograms/mL. The aqueous extracts of T. pusilla (100-250 micrograms/mL), B. teindalensis (50-125 micrograms/mL) and E. glutinosum (50-125 micrograms/mL) also inhibited the replication of VSV, but none of the extracts tested had any effect on poliovirus replication.

Insect antiviral innate immunity: pathways, effectors, and connections

PubMed Central

Kingsolver, Megan B.; Huang, Zhijing; Hardy, Richard W.

2014-01-01

Insects are infected by a wide array of viruses some of which are insect-restricted and pathogenic, and some of which are transmitted by biting insects to vertebrates. The medical and economic importance of these viruses heightens the need to understand the interaction between the infecting pathogen and the insect immune system in order to develop transmission interventions. The interaction of the virus with the insect host innate immune system plays a critical role in the outcome of infection. The major mechanism of antiviral defense is the siRNA pathway that responds through the detection of virus-derived dsRNA to suppress virus replication. However, other innate antimicrobial pathways such as Imd, Toll, Jak-STAT, and the autophagy pathway have also been shown to play important roles in antiviral immunity. In this review we provide an overview of the current understanding of the main insect antiviral pathways and examine recent findings that further our understanding of the roles of these pathways in facilitating a systemic and specific response to infecting viruses. PMID:24120681

Insect antiviral innate immunity: pathways, effectors, and connections.

PubMed

Kingsolver, Megan B; Huang, Zhijing; Hardy, Richard W

2013-12-13

Insects are infected by a wide array of viruses some of which are insect restricted and pathogenic, and some of which are transmitted by biting insects to vertebrates. The medical and economic importance of these viruses heightens the need to understand the interaction between the infecting pathogen and the insect immune system in order to develop transmission interventions. The interaction of the virus with the insect host innate immune system plays a critical role in the outcome of infection. The major mechanism of antiviral defense is the small, interfering RNA pathway that responds through the detection of virus-derived double-stranded RNA to suppress virus replication. However, other innate antimicrobial pathways such as Imd, Toll, and Jak-STAT and the autophagy pathway have also been shown to play important roles in antiviral immunity. In this review, we provide an overview of the current understanding of the main insect antiviral pathways and examine recent findings that further our understanding of the roles of these pathways in facilitating a systemic and specific response to infecting viruses. © 2013.

TRIM25 in the Regulation of the Antiviral Innate Immunity.

PubMed

Martín-Vicente, María; Medrano, Luz M; Resino, Salvador; García-Sastre, Adolfo; Martínez, Isidoro

2017-01-01

TRIM25 is an E3 ubiquitin ligase enzyme that is involved in various cellular processes, including regulation of the innate immune response against viruses. TRIM25-mediated ubiquitination of the cytosolic pattern recognition receptor RIG-I is an essential step for initiation of the intracellular antiviral response and has been thoroughly documented. In recent years, however, additional roles of TRIM25 in early innate immunity are emerging, including negative regulation of RIG-I, activation of the melanoma differentiation-associated protein 5-mitochondrial antiviral signaling protein-TRAF6 antiviral axis and modulation of p53 levels and activity. In addition, the ability of TRIM25 to bind RNA may uncover new mechanisms by which this molecule regulates intracellular signaling and/or RNA virus replication.

TRIM25 in the Regulation of the Antiviral Innate Immunity

PubMed Central

Martín-Vicente, María; Medrano, Luz M.; Resino, Salvador; García-Sastre, Adolfo; Martínez, Isidoro

2017-01-01

TRIM25 is an E3 ubiquitin ligase enzyme that is involved in various cellular processes, including regulation of the innate immune response against viruses. TRIM25-mediated ubiquitination of the cytosolic pattern recognition receptor RIG-I is an essential step for initiation of the intracellular antiviral response and has been thoroughly documented. In recent years, however, additional roles of TRIM25 in early innate immunity are emerging, including negative regulation of RIG-I, activation of the melanoma differentiation-associated protein 5–mitochondrial antiviral signaling protein–TRAF6 antiviral axis and modulation of p53 levels and activity. In addition, the ability of TRIM25 to bind RNA may uncover new mechanisms by which this molecule regulates intracellular signaling and/or RNA virus replication. PMID:29018447

Antiviral properties of deazaadenine nucleoside derivatives.

PubMed

Vittori, S; Dal Ben, D; Lambertucci, C; Marucci, G; Volpini, R; Cristalli, G

2006-01-01

Viral infections have menaced human beings since time immemorial, and even today new viral strains that cause lethal diseases are being discovered with alarming frequency. One major example is HIV, the etiological agent of AIDS, which spread up in the last two decades. Very recently, other virus based diseases such as avian flu have spread fear around the world, and hemorrhagic fevers from central Africa serious threaten human health because of their very deadly effects. New antiviral agents are still greatly needed to counter these menaces. Many scientists are involved in this field of research, and many of the recently discovered effective antiviral compounds are nucleoside analogues. Among those derivatives, deazapurine nucleoside analogues have demonstrated potent inhibitory effect of viral replication. This review reports on recently generated data from preparing and testing deazapurine nucleoside derivatives as inhibitors in virus replication systems. Although most of the reported data have been produced in antiHIV, antiHCMV, and antiHSV biological testing, very recently other new important fields of application have been discovered, all in topical subjects of strong interest. In fact, deazapurine nucleosides have been found to be active as chemotherapeutics for some veterinary systemic viral infections, for which no antiviral drugs are licensed yet. Furthermore, they demonstrated efficacy in the inhibition of Hepatitis C virus replication. Finally, these compounds showed high potency as virucides against Ebola Virus, curing Ebola infected mice with a single dose administration.

The history of hepatitis C virus (HCV): Basic research reveals unique features in phylogeny, evolution and the viral life cycle with new perspectives for epidemic control.

PubMed

Bukh, Jens

2016-10-01

The discovery of hepatitis C virus (HCV) in 1989 permitted basic research to unravel critical components of a complex life cycle for this important human pathogen. HCV is a highly divergent group of viruses classified in 7 major genotypes and a great number of subtypes, and circulating in infected individuals as a continuously evolving quasispecies destined to escape host immune responses and applied antivirals. Despite the inability to culture patient viruses directly in the laboratory, efforts to define the infectious genome of HCV resulted in development of experimental recombinant in vivo and in vitro systems, including replicons and infectious cultures in human hepatoma cell lines. And HCV has become a model virus defining new paradigms in virology, immunology and biology. For example, HCV research discovered that a virus could be completely dependent on microRNA for its replication since microRNA-122 is critical for the HCV life cycle. A number of other host molecules critical for HCV entry and replication have been identified. Thus, basic HCV research revealed important molecules for development of host targeting agents (HTA). The identification and characterization of HCV encoded proteins and their functional units contributed to the development of highly effective direct acting antivirals (DAA) against the NS3 protease, NS5A and the NS5B polymerase. In combination, these inhibitors have since 2014 permitted interferon-free therapy with cure rates above 90% among patients with chronic HCV infection; however, viral resistance represents a challenge. Worldwide control of HCV will most likely require the development of a prophylactic vaccine, and numerous candidates have been pursued. Research characterizing features critical for antibody-based virus neutralization and T cell based virus elimination from infected cells is essential for this effort. If the world community promotes an ambitious approach by applying current DAA broadly, continues to develop

Hepatitis C in injection drug users: It is time to treat.

PubMed

Grassi, Alberto; Ballardini, Giorgio

2017-05-28

Injection drug users (IDUs) are at risk of hepatitis C virus (HCV) infection, due to needle and syringe sharing. Chronic HCV infection is a major cause of liver-related morbidity and mortality but can be cured with antiviral treatment leading to sustained viral response (SVR). It is well demonstrated that, when close cooperation between specialists in drug addiction and psychiatrists is assured, patients on maintenance treatment with methadone/buprenorphine can be treated for HCV with response rate, tolerability and side effects similar to those reported in non-IDUs. Current guidelines recommend that active injection drug use should not exclude patients from HCV treatment, but many services remain reluctant to treat IDUs. No significant pharmacodynamic interactions were reported between approved direct anti-viral agents (DAAs) and buprenorphine or methadone. Dose adjustments are not recommended; therefore DAAs appear to be the "perfect" therapy for patients taking opiate substitutive therapy. These suggestions have been recently recognized by the European Association for the Study of the Liver (EASL) and included in EASL Recommendations on Treatment of Hepatitis C 2016. Guidelines confirm that HCV treatment for IDUs should be considered on an individualized basis and delivered within a multidisciplinary team setting; a history of intravenous drug use and recent drug use at treatment initiation are not associated with reduced SVR and decisions to treat must be made on a case-by-case basis.

Cycluridine: A novel antiviral effective against flaviviruses

PubMed Central

Galabov, Angel S; Mukova, Lucia; Abashev, Yuriy P; Wassilewa, Lilia; Tzvetkov, Petko; Minkov, Vassil; Barinskiy, Igor F; Rice, Charles M; Ouzounov, Sergey; Sidzhakova, Dorotea

2017-01-01

This review describes the contemporary state of research for antivirals effective against flaviviruses, especially focusing on inhibitors of the pestivirus causative agent of bovine viral diarrhoea virus. We highlight cycluridine, an originally synthesized Mannich’s base [a tetrahydro-2(1H)-pyrimidinones derivative], as a highly effective antiviral possessing a strong inhibitory effect on bovine viral diarrhoea virus replication. Cycluridine was active against replication of a wide variety of bovine viral diarrhoea virus strains in cell cultures. The drug-sensitive period in the bovine viral diarrhoea virus replication cycle included the latent period and the exponential phase; a 90-min delay in the peak of viral RNA synthesis was observed. Cycluridine administered orally manifested a pronounced protective effect in calves with natural mucosal disease/viral diarrhoea and calves experimentally infected with bovine viral diarrhoea virus. Its magnitude of activity and selectivity places cycluridine in the lead among all known substances with anti- bovine viral diarrhoea virus activity. Additionally, cycluridine applied subcutaneously showed anti-tick-born encephalitis virus activity, manifesting a marked protective effect in mice infected with tick-born encephalitis virus. Cycluridine could be a prospective antiviral in veterinary and medical practice for the treatment of bovine viral diarrhoea virus and other flavivirus infections. PMID:28768435

Antiviral activity of maca (Lepidium meyenii) against human influenza virus.

PubMed

Del Valle Mendoza, Juana; Pumarola, Tomàs; Gonzales, Libertad Alzamora; Del Valle, Luis J

2014-09-01

To investigate antiviral activity of maca to reduce viral load in Madin-Darby canine kidney (MDCK) cells infected with influenza type A and B viruses (Flu-A and Flu-B, respectively). Maca were extracted with methanol (1:2, v/v). The cell viability and toxicity of the extracts were evaluated on MDCK cells using method MTT assay. Antiviral activity of compounds against Flu-A and Flu-B viruses was assayed using a test for determining the inhibition of the cytopathic effect on cell culture and multiplex RT-PCR. The methanol extract of maca showed low cytotoxicity and inhibited influenza-induced cytopathic effect significantly, while viral load was reduced via inhibition of viral growth in MDCK infected cells. Maca contains potent inhibitors of Flu-A and Flu-B with a selectivity index [cytotoxic concentration 50%/IC50] of 157.4 and 110.5, respectively. In vitro assays demonstrated that maca has antiviral activity not only against Flu-A (like most antiviral agents) but also Flu-B viruses, providing remarkable therapeutic benefits. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

A novel peptide with potent and broad-spectrum antiviral activities against multiple respiratory viruses

PubMed Central

Zhao, Hanjun; Zhou, Jie; Zhang, Ke; Chu, Hin; Liu, Dabin; Poon, Vincent Kwok-Man; Chan, Chris Chung-Sing; Leung, Ho-Chuen; Fai, Ng; Lin, Yong-Ping; Zhang, Anna Jin-Xia; Jin, Dong-Yan; Yuen, Kwok-Yung; Zheng, Bo-Jian

2016-01-01

A safe, potent and broad-spectrum antiviral is urgently needed to combat emerging respiratory viruses. In light of the broad antiviral activity of β-defensins, we tested the antiviral activity of 11 peptides derived from mouse β-defensin-4 and found that a short peptide, P9, exhibited potent and broad-spectrum antiviral effects against multiple respiratory viruses in vitro and in vivo, including influenza A virus H1N1, H3N2, H5N1, H7N7, H7N9, SARS-CoV and MERS-CoV. The antiviral activity of P9 was attributed to its high-affinity binding to viral glycoproteins, as well as the abundance of basic amino acids in its composition. After binding viral particles through viral surface glycoproteins, P9 entered into cells together with the viruses via endocytosis and prevented endosomal acidification, which blocked membrane fusion and subsequent viral RNA release. This study has paved the avenue for developing new prophylactic and therapeutic agents with broad-spectrum antiviral activities. PMID:26911565

Direct Acting Antiviral Agents in Korean Patients with Chronic Hepatitis C and Hemophilia Who Are Treatment-Naïve or Treatment-Experienced.

PubMed

Lee, Hyun Woong; Yoo, Ki Young; Won, Joung Won; Kim, Hyung Joon

2017-09-15

Chronic hepatitis C (CHC) is a major comorbidity in patients with hemophilia. Patients (n=30) were enrolled between September 2015 and April 2016. Twenty-six patients were genotype 1 (1b, n=21; 1a, n=5) and four patients were genotype 2a/2b. Among 21 patients with genotype 1b, Y93H resistance-associated variants (RAVs) were detected in three patients (14.3%). We evaluated sustained virologic response (SVRs) at 12 weeks, as well as relapse and safety. Five patients with genotype 1a and three patients with genotype 1b (RAV positive) received ledipasvir/sofosbuvir for 12 weeks. SVR12 rate was 100% (8/8). Eleven patients with genotype 1b were treatment-naïve and received daclatasvir plus asunaprevir for 24 weeks. SVR12 rate was 91% (10/11). One patient experienced viral breakthrough without RAV at 12 weeks. Seven treatment-experienced patients with genotype 1b received daclatasvir plus asunaprevir for 24 weeks. SVR12 rate was 85.7% (6/7). One patient experienced viral breakthrough with RAV (L31M, Y93H) at 12 weeks. Four patients with genotype 2a/2b received sofosbuvir plus ribavirin for 12 weeks. SVR12 rate was 100% (4/4). No serious adverse event-related discontinuations were noted. New direct acting antiviral treatment achieved high SVRs rates at 12 weeks in CHC patients with hemophilia without serious adverse events.

Direct Acting Antiviral Agents in Korean Patients with Chronic Hepatitis C and Hemophilia Who Are Treatment-Naïve or Treatment-Experienced

PubMed Central

Lee, Hyun Woong; Yoo, Ki Young; Won, Joung Won; Kim, Hyung Joon

2017-01-01

Background/Aims Chronic hepatitis C (CHC) is a major comorbidity in patients with hemophilia. Methods Patients (n=30) were enrolled between September 2015 and April 2016. Twenty-six patients were genotype 1 (1b, n=21; 1a, n=5) and four patients were genotype 2a/2b. Among 21 patients with genotype 1b, Y93H resistance-associated variants (RAVs) were detected in three patients (14.3%). We evaluated sustained virologic response (SVRs) at 12 weeks, as well as relapse and safety. Results Five patients with genotype 1a and three patients with genotype 1b (RAV positive) received ledipasvir/sofosbuvir for 12 weeks. SVR12 rate was 100% (8/8). Eleven patients with genotype 1b were treatment-naïve and received daclatasvir plus asunaprevir for 24 weeks. SVR12 rate was 91% (10/11). One patient experienced viral breakthrough without RAV at 12 weeks. Seven treatment-experienced patients with genotype 1b received daclatasvir plus asunaprevir for 24 weeks. SVR12 rate was 85.7% (6/7). One patient experienced viral breakthrough with RAV (L31M, Y93H) at 12 weeks. Four patients with genotype 2a/2b received sofosbuvir plus ribavirin for 12 weeks. SVR12 rate was 100% (4/4). No serious adverse event-related discontinuations were noted. Conclusions New direct acting antiviral treatment achieved high SVRs rates at 12 weeks in CHC patients with hemophilia without serious adverse events. PMID:28874040

HCV Treatment Initiation in Patients with Chronic Kidney Disease: Results from ERCHIVES

PubMed Central

Butt, Adeel; Ren, Yanjie; Puenpatom, Amy; Arduino, Jean Marie; Kumar, Ritesh; Abou-Samra, Abdul-Badi

2017-01-01

Abstract Background Newer directing antiviral agents against HCV (DAAs) are safe and efficacious in persons with chronic kidney disease (CKD). Whether availability of these newer DAAs has resulted in more persons with CKD initiating HCV treatment remains unknown. Methods We identified HCV+ persons in ERCHIVES. We excluded HIV+ and HBsAg+ and those with missing HCV RNA and eGFR data. We determined the CKD stage according to National Kidney Foundation criteria. We determined the number of persons initiated on any of the approved DAA-regimen (defined as >14 days of DAA prescription). Logistic regression analyses was used to determine factors associated with treatment initiation. Results Among 76,513 evaluable persons, 21.1% initiated DAA treatment. Initiation rates differed significantly by CKD stage: 21.1% (15,136/68,469) for eGFR>90mL/minute/1.73m2 and CKD stage-2; 14.0% 9853/6,086) for CKD stage 3; and 7.6% (148/1,958) for CKD stage-4/5. Those with CKD stage-3 were 35% less likely and those with CKD stage-4/5 were 65% less likely to initiate treatment with a DAA compared with those with baseline eGFR>90mL/minute/1.73m2. Those with Body Mass Index (BMI)>30 were more likely to initiate treatment (OR 1.24, 95% CI 1.19,1.29). Treatment initiation was less likely in HCV genotype 2 or 3 and those with diabetes (OR 0.82, 95% CI 0.78,0.86), cardiovascular disease (OR 0.73, 95% CI 0.68,0.78), alcohol abuse or dependence (OR 0.75, 95% CI 0.72,0.78) or cirrhosis (OR 0.85, 95% CI 0.80,0.89) at baseline. Conclusion Persons with more advanced CKD are less likely to receive treatment for HCV. Strategies are needed to improve treatment rates in the HCV/CKD population. Disclosures A. Butt, Merck: Investigator, Grant recipient. A. Puenpatom, Merck: Employee, Salary. J. M. Arduino, Merck: Employee, Salary. R. Kumar, Merck: Employee, Salary

Cytotoxic, Virucidal, and Antiviral Activity of South American Plant and Algae Extracts

PubMed Central

Faral-Tello, Paula; Mirazo, Santiago; Dutra, Carmelo; Pérez, Andrés; Geis-Asteggiante, Lucía; Frabasile, Sandra; Koncke, Elina; Davyt, Danilo; Cavallaro, Lucía; Heinzen, Horacio; Arbiza, Juan

2012-01-01

Herpes simplex virus type 1 (HSV-1) infection has a prevalence of 70% in the human population. Treatment is based on acyclovir, valacyclovir, and foscarnet, three drugs that share the same mechanism of action and of which resistant strains have been isolated from patients. In this aspect, innovative drug therapies are required. Natural products offer unlimited opportunities for the discovery of antiviral compounds. In this study, 28 extracts corresponding to 24 plant species and 4 alga species were assayed in vitro to detect antiviral activity against HSV-1. Six of the methanolic extracts inactivated viral particles by direct interaction and 14 presented antiviral activity when incubated with cells already infected. Most interesting antiviral activity values obtained are those of Limonium brasiliense, Psidium guajava, and Phyllanthus niruri, which inhibit HSV-1 replication in vitro with 50% effective concentration (EC50) values of 185, 118, and 60 μg/mL, respectively. For these extracts toxicity values were calculated and therefore selectivity indexes (SI) obtained. Further characterization of the bioactive components of antiviral plants will pave the way for the discovery of new compounds against HSV-1. PMID:22619617

Is hepatitis C virus elimination possible among people living with HIV and what will it take to achieve it?

PubMed

Martin, Natasha K; Boerekamps, Anne; Hill, Andrew M; Rijnders, Bart J A

2018-04-01

The World Health Organization targets for hepatitis C virus (HCV) elimination include a 90% reduction in new infections by 2030. Our objective is to review the modelling evidence and cost data surrounding feasibility of HCV elimination among people living with HIV (PLWH), and identify likely components for elimination. We also discuss the real-world experience of HCV direct acting antiviral (DAA) scale-up and elimination efforts in the Netherlands. We review modelling evidence of what intervention scale-up is required to achieve WHO HCV elimination targets among HIV-infected (HIV+) people who inject drugs (PWID) and men who have sex with men (MSM), review cost-effectiveness of HCV therapy among PLWH and discuss economic implications of elimination. We additionally use the real-world experience of DAA scale-up in the Netherlands to illustrate the promise and potential challenges of HCV elimination strategies in MSM. Finally, we summarize key components of the HCV elimination response among PWLH. Modelling indicates HCV elimination among HIV+ MSM and PWID is potentially achievable but requires combination treatment and either harm reduction or behavioural risk reductions. Preliminary modelling indicates elimination among HIV+ PWID will require elimination efforts among PWID more broadly. Treatment for PLWH and high-risk populations (PWID and MSM) is cost-effective in high-income countries, but costs of DAAs remain a barrier to scale-up worldwide despite the potential low production price ($50 per 12 week course). In the Netherlands, universal DAA availability led to rapid uptake among HIV+ MSM in 2015/16, and a 50% reduction in acute HCV incidence among HIV+ MSM from 2014 to 2016 was observed. In addition to HCV treatment, elimination among PLWH globally also likely requires regular HCV testing, development of low-cost accurate HCV diagnostics, reduced costs of DAA therapy, broad treatment access without restrictions, close monitoring for HCV reinfection and

Infection-specific phosphorylation of glutamyl-prolyl tRNA synthetase induces antiviral immunity

PubMed Central

Lee, Eun-Young; Lee, Hyun-Cheol; Kim, Hyun-Kwan; Jang, Song Yee; Park, Seong-Jun; Kim, Yong-Hoon; Kim, Jong Hwan; Hwang, Jungwon; Kim, Jae-Hoon; Kim, Tae-Hwan; Arif, Abul; Kim, Seon-Young; Choi, Young-Ki; Lee, Cheolju; Lee, Chul-Ho; Jung, Jae U; Fox, Paul L; Kim, Sunghoon; Lee, Jong-Soo; Kim, Myung Hee

2016-01-01

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/−) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection. PMID:27595231

A new mechanism of interferon's antiviral action: Induction of autophagy, essential for paramyxovirus replication, is inhibited by the interferon stimulated gene, TDRD7.

PubMed

Subramanian, Gayatri; Kuzmanovic, Teodora; Zhang, Ying; Peter, Cara Beate; Veleeparambil, Manoj; Chakravarti, Ritu; Sen, Ganes C; Chattopadhyay, Saurabh

2018-01-01

The interferon (IFN) system represents the first line of defense against a wide range of viruses. Virus infection rapidly triggers the transcriptional induction of IFN-β and IFN Stimulated Genes (ISGs), whose protein products act as viral restriction factors by interfering with specific stages of virus life cycle, such as entry, transcription, translation, genome replication, assembly and egress. Here, we report a new mode of action of an ISG, IFN-induced TDRD7 (tudor domain containing 7) inhibited paramyxovirus replication by inhibiting autophagy. TDRD7 was identified as an antiviral gene by a high throughput screen of an ISG shRNA library for blocking IFN's protective effect against Sendai virus (SeV) replication. The antiviral activity of TDRD7 against SeV, human parainfluenza virus 3 and respiratory syncytial virus was confirmed by its genetic ablation or ectopic expression in several types of mouse and human cells. TDRD7's antiviral action was mediated by its ability to inhibit autophagy, a cellular catabolic process which was robustly induced by SeV infection and required for its replication. Mechanistic investigation revealed that TDRD7 interfered with the activation of AMP-dependent kinase (AMPK), an enzyme required for initiating autophagy. AMPK activity was required for efficient replication of several paramyxoviruses, as demonstrated by its genetic ablation or inhibition of its activity by TDRD7 or chemical inhibitors. Therefore, our study has identified a new antiviral ISG with a new mode of action.

Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

NASA Astrophysics Data System (ADS)

Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

2015-09-01

Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

Favipiravir elicits antiviral mutagenesis during virus replication in vivo.

PubMed

Arias, Armando; Thorne, Lucy; Goodfellow, Ian

2014-10-21

Lethal mutagenesis has emerged as a novel potential therapeutic approach to treat viral infections. Several studies have demonstrated that increases in the high mutation rates inherent to RNA viruses lead to viral extinction in cell culture, but evidence during infections in vivo is limited. In this study, we show that the broad-range antiviral nucleoside favipiravir reduces viral load in vivo by exerting antiviral mutagenesis in a mouse model for norovirus infection. Increased mutation frequencies were observed in samples from treated mice and were accompanied with lower or in some cases undetectable levels of infectious virus in faeces and tissues. Viral RNA isolated from treated animals showed reduced infectivity, a feature of populations approaching extinction during antiviral mutagenesis. These results suggest that favipiravir can induce norovirus mutagenesis in vivo, which in some cases leads to virus extinction, providing a proof-of-principle for the use of favipiravir derivatives or mutagenic nucleosides in the clinical treatment of noroviruses.

Evolution and Antiviral Specificities of Interferon-Induced Mx Proteins of Bats against Ebola, Influenza, and Other RNA Viruses

PubMed Central

Fuchs, Jonas; Hölzer, Martin; Schilling, Mirjam; Patzina, Corinna; Schoen, Andreas; Zimmer, Gert; Marz, Manja; Müller, Marcel A.

2017-01-01

ABSTRACT Bats serve as a reservoir for various, often zoonotic viruses, including significant human pathogens such as Ebola and influenza viruses. However, for unknown reasons, viral infections rarely cause clinical symptoms in bats. A tight control of viral replication by the host innate immune defense might contribute to this phenomenon. Transcriptomic studies revealed the presence of the interferon-induced antiviral myxovirus resistance (Mx) proteins in bats, but detailed functional aspects have not been assessed. To provide evidence that bat Mx proteins might act as key factors to control viral replication we cloned Mx1 cDNAs from three bat families, Pteropodidae, Phyllostomidae, and Vespertilionidae. Phylogenetically these bat Mx1 genes cluster closely with their human ortholog MxA. Using transfected cell cultures, minireplicon systems, virus-like particles, and virus infections, we determined the antiviral potential of the bat Mx1 proteins. Bat Mx1 significantly reduced the polymerase activity of viruses circulating in bats, including Ebola and influenza A-like viruses. The related Thogoto virus, however, which is not known to infect bats, was not inhibited by bat Mx1. Further, we provide evidence for positive selection in bat Mx1 genes that might explain species-specific antiviral activities of these proteins. Together, our data suggest a role for Mx1 in controlling these viruses in their bat hosts. IMPORTANCE Bats are a natural reservoir for various viruses that rarely cause clinical symptoms in bats but are dangerous zoonotic pathogens, like Ebola or rabies virus. It has been hypothesized that the interferon system might play a key role in controlling viral replication in bats. We speculate that the interferon-induced Mx proteins might be key antiviral factors of bats and have coevolved with bat-borne viruses. This study evaluated for the first time a large set of bat Mx1 proteins spanning three major bat families for their antiviral potential, including

Real-world challenges for hepatitis C virus medications: a critical overview.

PubMed

Shahid, Imran; AlMalki, Waleed Hassan; Hassan, Sajida; Hafeez, Muhammad Hassan

2018-03-01

From 2010, the landscape of hepatitis C therapeutics has been changed rapidly, and today we are standing at a cusp of a pharmacological revolution where highly effective and interferon (IFN)-free direct acting antivirals (DAAs) are already on the market. Such treatment paradigms attain 90-95% sustained virologic response (SVR; undetectable viral load at week 12 or 24 at the end of therapy) rates in treated individuals compared to 50-70% with treatment completion of dual-therapy-pegylated interferon (PEG-IFN) and ribavirin (RBV). As the major goal now for the hepatologists, clinicians, physicians, and health care workers is likely to eradicate hepatitis C infection in parallel to treatment, the demand is for a one-size-fits-all pill that could be prescribed beyond the limitations of hepatitis C genotype, viral load, previous treatment history, advanced hepatic manifestations (fibrosis, cirrhosis) and antiviral drug resistance. Although the new treatment strategies have shown high cure rates in clinical trials, such treatment paradigms are posing dilemmas too in real-world clinical practice. Therapy cost, treatment access to low and middle-income countries, treatment-emergent adverse events, lack of effective viral screening and disease progression simulation models are potential challenges in this prospect. This review article deeply overviews the challenges encountered while surmounting the burden of hepatitis C around the world.

Mitochondrially localised MUL1 is a novel modulator of antiviral signaling.

PubMed

Jenkins, Kristie; Khoo, Jing Jing; Sadler, Anthony; Piganis, Rebecca; Wang, Die; Borg, Natalie A; Hjerrild, Kathryn; Gould, Jodee; Thomas, Belinda J; Nagley, Phillip; Hertzog, Paul J; Mansell, Ashley

2013-04-01

The innate immune response to virus must be balanced to eliminate infection yet limit damaging inflammation. A critical arm of the antiviral response is launched by the retinoic acid-inducible-gene I (RIG-I) protein. RIG-I is activated by viral RNA then associates with the mitochondrial antiviral signaling (MAVS) protein to subsequently induce potent inflammatory cytokines. Here, we demonstrate the mitochondrial E3 ubiquitin protein ligase 1 (MUL1) is a crucial moderator of RIG-I signaling. MUL1 is localized to the mitochondria where it interacts with MAVS and catalyzes RIG-I post-translational modifications that inhibit RIG-I-dependent cell signaling. Accordingly, depletion of MUL1 potentiated RIG-I mediated nuclear factor-kappa B (NF-κB) and interferon (IFN) β reporter activity. Moreover, depletion of MUL1 boosted the antiviral response and increased proinflammatory cytokines following challenge with the RNA mimetic poly I:C and Sendai virus. We therefore submit that MUL1 is a novel regulator of the RIG-I-like receptor-dependent antiviral response, that otherwise functions to limit inflammation.

Automated synthesis of 4-[(18)F]fluoroanisole, [(18)F]DAA1106 and 4-[(18)F]FPhe using Cu-mediated radiofluorination under "minimalist" conditions.

PubMed

Zischler, Johannes; Krapf, Philipp; Richarz, Raphael; Zlatopolskiy, Boris D; Neumaier, Bernd

2016-09-01

The application of the "minimalist" approach to Cu-mediated radiofluorination allows the efficient preparation of (18)F-labeled arenes regardless of their electronic properties. The implementation of this methodology on a commercially available synthesis module (hotbox(three), Scintomics, Germany) enabled the automated production of 4-[(18)F]fluoroanisole as well as the clinically relevant PET-tracers, 4-[(18)F]FPhe and [(18)F]DAA1106, in radiochemical yields of 41-61% and radiochemical purities of >95% within 30-60min. These results demonstrated the high efficacy and versatility of the developed method that will open up opportunities for a broad application of Cu-mediated radiofluorination in PET-chemistry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extraribosomal L13a Is a Specific Innate Immune Factor for Antiviral Defense

PubMed Central

Poddar, Darshana; Basu, Abhijit; Kour, Ravinder; Verbovetskaya, Valentina

2014-01-01

ABSTRACT We report a novel extraribosomal innate immune function of mammalian ribosomal protein L13a, whereby it acts as an antiviral agent. We found that L13a is released from the 60S ribosomal subunit in response to infection by respiratory syncytial virus (RSV), an RNA virus of the Pneumovirus genus and a serious lung pathogen. Unexpectedly, the growth of RSV was highly enhanced in L13a-knocked-down cells of various lineages as well as in L13a knockout macrophages from mice. In all L13a-deficient cells tested, translation of RSV matrix (M) protein was specifically stimulated, as judged by a greater abundance of M protein and greater association of the M mRNA with polyribosomes, while general translation was unaffected. In silico RNA folding analysis and translational reporter assays revealed a putative hairpin in the 3′untranslated region (UTR) of M mRNA with significant structural similarity to the cellular GAIT (gamma-activated inhibitor of translation) RNA hairpin, previously shown to be responsible for assembling a large, L13a-containing ribonucleoprotein complex that promoted translational silencing in gamma interferon (IFN-γ)-activated myeloid cells. However, RNA-protein interaction studies revealed that this complex, which we named VAIT (respiratory syncytial virus-activated inhibitor of translation) is functionally different from the GAIT complex. VAIT is the first report of an extraribosomal L13a-mediated, IFN-γ-independent innate antiviral complex triggered in response to virus infection. We provide a model in which the VAIT complex strongly hinders RSV replication by inhibiting the translation of the rate-limiting viral M protein, which is a new paradigm in antiviral defense. IMPORTANCE The innate immune mechanisms of host cells are diverse in nature and act as a broad-spectrum cellular defense against viruses. Here, we report a novel innate immune mechanism functioning against respiratory syncytial virus (RSV), in which the cellular ribosomal

Strategies for antiviral stockpiling for future influenza pandemics: a global epidemic-economic perspective

PubMed Central

Carrasco, Luis R.; Lee, Vernon J.; Chen, Mark I.; Matchar, David B.; Thompson, James P.; Cook, Alex R.

2011-01-01

Influenza pandemics present a global threat owing to their potential mortality and substantial economic impacts. Stockpiling antiviral drugs to manage a pandemic is an effective strategy to offset their negative impacts; however, little is known about the long-term optimal size of the stockpile under uncertainty and the characteristics of different countries. Using an epidemic–economic model we studied the effect on total mortality and costs of antiviral stockpile sizes for Brazil, China, Guatemala, India, Indonesia, New Zealand, Singapore, the UK, the USA and Zimbabwe. In the model, antivirals stockpiling considerably reduced mortality. There was greater potential avoidance of expected costs in the higher resourced countries (e.g. from $55 billion to $27 billion over a 30 year time horizon for the USA) and large avoidance of fatalities in those less resourced (e.g. from 11.4 to 2.3 million in Indonesia). Under perfect allocation, higher resourced countries should aim to store antiviral stockpiles able to cover at least 15 per cent of their population, rising to 25 per cent with 30 per cent misallocation, to minimize fatalities and economic costs. Stockpiling is estimated not to be cost-effective for two-thirds of the world's population under current antivirals pricing. Lower prices and international cooperation are necessary to make the life-saving potential of antivirals cost-effective in resource-limited countries. PMID:21296791

Strategies for antiviral stockpiling for future influenza pandemics: a global epidemic-economic perspective.

PubMed

Carrasco, Luis R; Lee, Vernon J; Chen, Mark I; Matchar, David B; Thompson, James P; Cook, Alex R

2011-09-07

Influenza pandemics present a global threat owing to their potential mortality and substantial economic impacts. Stockpiling antiviral drugs to manage a pandemic is an effective strategy to offset their negative impacts; however, little is known about the long-term optimal size of the stockpile under uncertainty and the characteristics of different countries. Using an epidemic-economic model we studied the effect on total mortality and costs of antiviral stockpile sizes for Brazil, China, Guatemala, India, Indonesia, New Zealand, Singapore, the UK, the USA and Zimbabwe. In the model, antivirals stockpiling considerably reduced mortality. There was greater potential avoidance of expected costs in the higher resourced countries (e.g. from $55 billion to $27 billion over a 30 year time horizon for the USA) and large avoidance of fatalities in those less resourced (e.g. from 11.4 to 2.3 million in Indonesia). Under perfect allocation, higher resourced countries should aim to store antiviral stockpiles able to cover at least 15 per cent of their population, rising to 25 per cent with 30 per cent misallocation, to minimize fatalities and economic costs. Stockpiling is estimated not to be cost-effective for two-thirds of the world's population under current antivirals pricing. Lower prices and international cooperation are necessary to make the life-saving potential of antivirals cost-effective in resource-limited countries.

Antiviral immunity following smallpox virus infection: a case-control study.

PubMed

Hammarlund, Erika; Lewis, Matthew W; Hanifin, Jon M; Mori, Motomi; Koudelka, Caroline W; Slifka, Mark K

2010-12-01

Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4(+) and CD8(+) T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases.

Antiviral Immunity following Smallpox Virus Infection: a Case-Control Study▿

PubMed Central

Hammarlund, Erika; Lewis, Matthew W.; Hanifin, Jon M.; Mori, Motomi; Koudelka, Caroline W.; Slifka, Mark K.

2010-01-01

Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4+ and CD8+ T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases. PMID:20926574

Cocaine evokes a profile of oxidative stress and impacts innate antiviral response pathways in astrocytes.

PubMed

Cisneros, Irma E; Erdenizmenli, Mert; Cunningham, Kathryn A; Paessler, Slobodan; Dineley, Kelly T

2018-06-01

HIV-1 and Zika virus (ZIKV) represent RNA viruses with neurotropic characteristics. Infected individuals suffer neurocognitive disorders aggravated by environmental toxins, including drugs of abuse such as cocaine, exacerbating HIV-associated neurocognitive disorders through a combination of astrogliosis, oxidative stress and innate immune signaling; however, little is known about how cocaine impacts the progression of ZIKV neural perturbations. Impaired innate immune signaling is characterized by weakened antiviral activation of interferon signaling and alterations in inflammatory signaling, factors contributing to cognitive sequela associated with cocaine in HIV-1/ZIKV infection. We employed cellular/molecular biology techniques to test if cocaine suppresses the efficacy of astrocytes to initiate a Type 1 interferon response to HIV-1/ZIKV, in vitro. We found cocaine activated antiviral signaling pathways and type I interferon in the absence of inflammation. Cocaine pre-exposure suppressed antiviral responses to HIV-1/ZIKV, triggering antiviral signaling and phosphorylation of interferon regulatory transcription factor 3 to stimulate type I interferon gene transcription. Our data indicate that oxidative stress is a major driver of cocaine-mediated astrocyte antiviral immune responses. Although astrocyte antiviral signaling is activated following detection of foreign pathogenic material, oxidative stress and increased cytosolic double-stranded DNA (dsDNA) can drive antiviral signaling via stimulation of pattern recognition receptors. Pretreatment with the glial modulators propentofylline (PPF) or pioglitazone (PIO) reversed cocaine-mediated attenuation of astrocyte responses to HIV-1/ZIKV. Both PPF/PIO protected against cocaine-mediated generation of reactive oxygen species (ROS), increased dsDNA, antiviral signaling pathways and increased type I interferon, indicating that cocaine induces astrocyte type I interferon signaling in the absence of virus and oxidative

Antiviral evaluation of plants from Brazilian Atlantic Tropical Forest.

PubMed

Andrighetti-Fröhner, C R; Sincero, T C M; da Silva, A C; Savi, L A; Gaido, C M; Bettega, J M R; Mancini, M; de Almeida, M T R; Barbosa, R A; Farias, M R; Barardi, C R M; Simões, C M O

2005-06-01

The antiviral activity of six medicinal plants from Brazilian Atlantic Tropical Forest was investigated against two viruses: herpes simplex virus type 1 (HSV-1) and poliovirus type 2 (PV-2). Cuphea carthagenensis and Tillandsia usneoides extracts showed the best antiherpes activity. T. usneoides dichloromethane, ethyl acetate and n-butanol extracts, and Lippia alba n-butanol extract showed inhibition of HSV-1, strain 29R/acyclovir resistant. In addition, only L. alba ethyl acetate extract showed antipoliovirus activity. These results corroborate that medicinal plants can be a rich source of potential antiviral compounds.

Simultaneous quantitation of two direct acting hepatitis C antivirals (sofosbuvir and daclatasvir) by an HPLC-UV method designated for their pharmacokinetic study in rabbits.

PubMed

Atia, Noha N; El-Shaboury, Salwa R; El-Gizawy, Samia M; Abo-Zeid, Mohammad Nabil

2018-05-22

Sofosbuvir (SOF) and daclatasvir (DCS) are novel, recently developed direct acting antiviral agents characterized by potent anti-hepatitis C virus action. A fast and efficient HPLC-UV method was developed, validated and applied for simultaneous determination of SOF and DCS in pharmaceutical formulations and biological fluids based on coupling liquid-liquid extraction with ultrasound and dual wavelength detection at λ max ; 260 and 313 nm for SOF and DCS, respectively. This approach provided simple, sensitive, specific and cost-effective determination of the SOF-DCS mixture with good recoveries of the analytes from plasma. Analytes were separated within 7 min on C 18 analytical column with acetonitrile-10 mM acetate buffer of pH 5.0 at a flow rate of 1.0 mL min -1 . The linear ranges were 1-20 μg mL -1 for SOF and 0.6-6 μg mL -1 for DCS with correlation coefficients ≥0.9995. The detection limits in spiked rabbit plasma were 0.20 and 0.19 μg mL -1 for SOF and DCS, respectively. The method was validated according to ICH and US-FDA guidelines. Finally, the method was successfully applied for simultaneous pharmacokinetic studies of SOF and DCS in rabbits using rofecoxib as internal standard. Copyright © 2018 Elsevier B.V. All rights reserved.

Spectroscopic investigation of herpes simplex viruses infected cells and their response to antiviral therapy

NASA Astrophysics Data System (ADS)

Erukhimovitch, Vitaly; Talyshinsky, Marina; Souprun, Yelena; Huleihel, Mahmoud

2006-07-01

In the present study, we used microscopic Fourier transform infrared spectroscopy (FTIR) to evaluate the antiviral activity of known antiviral agents against herpes viruses. The antiviral activity of Caffeic acid phenethyl ester (CAPE) (which is an active compound of propolis) against herpes simplex type 1 and 2 was examined in cell culture. The advantage of microscopic FTIR spectroscopy over conventional FTIR spectroscopy is that it facilitates inspection of restricted regions of cell culture or tissue. Our results showed significant spectral differences at early stages of infection between infected and non-infected cells, and between infected cells treated with the used antiviral agent and those not treated. In infected cells, there was a considerable increase in phosphate levels. Our results show that treatment with used antiviral agent considerably abolish the spectral changes induced by the viral infection. In addition, it is possible to track by FTIR microscopy method the deferential effect of various doses of the drug.

Use of influenza antiviral agents by ambulatory care clinicians during the 2012-2013 influenza season.

PubMed

Havers, Fiona; Thaker, Swathi; Clippard, Jessie R; Jackson, Michael; McLean, Huong Q; Gaglani, Manjusha; Monto, Arnold S; Zimmerman, Richard K; Jackson, Lisa; Petrie, Josh G; Nowalk, Mary Patricia; Moehling, Krissy K; Flannery, Brendan; Thompson, Mark G; Fry, Alicia M

2014-09-15

Early antiviral treatment (≤2 days since illness onset) of influenza reduces the probability of influenza-associated complications. Early empiric antiviral treatment is recommended for those with suspected influenza at higher risk for influenza complications regardless of their illness severity. We describe antiviral receipt among outpatients with acute respiratory illness (ARI) and antibiotic receipt among patients with influenza. We analyzed data from 5 sites in the US Influenza Vaccine Effectiveness Network Study during the 2012-2013 influenza season. Subjects were outpatients aged ≥6 months with ARI defined by cough of ≤7 days' duration; all were tested for influenza by polymerase chain reaction (PCR). Medical history and prescription information were collected by medical and pharmacy records. Four sites collected prescribing data on 3 common antibiotics (amoxicillin-clavulanate, amoxicillin, and azithromycin). Of 6766 enrolled ARI patients, 509 (7.5%) received an antiviral prescription. Overall, 2366 (35%) had PCR-confirmed influenza; 355 (15%) of those received an antiviral prescription. Among 1021 ARI patients at high risk for influenza complications (eg, aged <2 years or ≥65 years or with ≥1 chronic medical condition) presenting to care ≤2 days from symptom onset, 195 (19%) were prescribed an antiviral medication. Among participants with PCR-confirmed influenza and antibiotic data, 540 of 1825 (30%) were prescribed 1 of 3 antibiotics; 297 of 1825 (16%) were prescribed antiviral medications. Antiviral treatment was prescribed infrequently among outpatients with influenza for whom therapy would be most beneficial; in contrast, antibiotic prescribing was more frequent. Continued efforts to educate clinicians on appropriate antibiotic and antiviral use are essential to improve healthcare quality. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee

Identification of Novel 5,6-Dimethoxyindan-1-one Derivatives as Antiviral Agents.

PubMed

Patil, Siddappa A; Patil, Vikrant; Patil, Renukadevi; Beaman, Kenneth; Patil, Shivaputra A

2017-01-01

Discovery of novel antiviral agents is essential because viral infection continues to threaten human life globally. Various heterocyclic small molecules have been developed as antiviral agents. The 5,6-dimethoxyindan-1-on nucleus is of considerable interest as this ring is the key constituent in a range of bioactive compounds, both naturally occurring and synthetic, and often of considerable complexity. The main purpose of this research was to discover and develop small molecule heterocycles as broad-spectrum of antiviral agents. A focused small set of 5,6-dimethoxyindan-1-one analogs (6-8) along with a thiopene derivative (9) was screened for selected viruses (Vaccinia virus - VACA, Human papillomavirus - HPV, Zika virus - ZIKV, Dengue virus - DENV, Measles virus - MV, Poliovirus 3 - PV, Rift Valley fever virus - RVFV, Tacaribe virus - TCRV, Venezuelan equine encephalitis virus - VEEV, Herpes simplex virus 1 -HSV-1 and Human cytomegalovirus - HCMV) using the National Institute of Allergy and Infectious Diseases (NIAID)'s Division of Microbiology and Infectious Diseases (DMID) antiviral screening program. These molecules demonstrated moderate to excellent antiviral activity towards variety of viruses. The 5,6-dimethoxyindan-1-one analog (7) demonstrated high efficacy towards vaccinia virus (EC50: <0.05 µM) and was nearly 232 times more potent than the standard drug Cidofovir (EC50: 11.59 µM) in primary assay whereas it demonstrated moderate activity (EC50: >30.00 µM) in secondary plaque reduction assay. The thiophene analog (9) has shown very good viral inhibition towards several viruses such as Human papillomavirus, Measles virus, Rift Valley fever virus, Tacaribe virus and Herpes simplex virus 1. Our research identified a novel 5,6-dimethoxyindan-1-one analog (compound 7), as a potent antiviral agent for vaccinia virus, and heterocyclic chalcone analog (compound 9) as a broad spectrum antiviral agent. Copyright© Bentham Science Publishers; For any queries

Human influenza is more effective than avian influenza at antiviral suppression in airway cells.

PubMed

Hsu, Alan Chen-Yu; Barr, Ian; Hansbro, Philip M; Wark, Peter A

2011-06-01

Airway epithelial cells are the initial site of infection with influenza viruses. The innate immune responses of airway epithelial cells to infection are important in limiting virus replication and spread. However, relatively little is known about the importance of this innate antiviral response to infection. Avian influenza viruses are a potential source of future pandemics; therefore, it is critical to examine the effectiveness of the host antiviral system to different influenza viruses. We used a human influenza (H3N2) and a low-pathogenic avian influenza (H11N9) to assess and compare the antiviral responses of Calu-3 cells. After infection, H3N2 replicated more effectively than the H11N9 in Calu-3 cells. This was not due to differential expression of sialic acid residues on Calu-3 cells, but was attributed to the interference of host antiviral responses by H3N2. H3N2 induced a delayed antiviral signaling and impaired type I and type III IFN induction compared with the H11N9. The gene encoding for nonstructural (NS) 1 protein was transfected into the bronchial epithelial cells (BECs), and the H3N2 NS1 induced a greater inhibition of antiviral responses compared with the H11N9 NS1. Although the low-pathogenic avian influenza virus was capable of infecting BECs, the human influenza virus replicated more effectively than avian influenza virus in BECs, and this was due to a differential ability of the two NS1 proteins to inhibit antiviral responses. This suggests that the subversion of human antiviral responses may be an important requirement for influenza viruses to adapt to the human host and cause disease.

Antiviral Activity of Polyacrylic and Polymethacrylic Acids

PubMed Central

De Somer, P.; De Clercq, E.; Billiau, A.; Schonne, E.; Claesen, M.

1968-01-01

A marked virus-inhibiting potency is obtained in the serum after intraperitoneal injection of polyacrylic acid (PAA) and polymethacrylic acid (PMAA) in mice. Much higher antiviral levels were reached than for other related polymers including dextran sulfate, heparin, polyvinyl sulfate, pyran copolymer, polystyrene sulfonate, and macrodex. The broad antiviral action of PAA and PMAA was attributed both to a direct interference with the virus-cell interaction and the viral ribonucleic acid metabolism and to the formation of an interferon-like factor. Both polyanions differed in interferon-inducing ability: highest serum interferon titer was obtained 18 hr after the intraperitoneal injection of PAA. The mechanism of interferon production by PAA and PMAA is discussed. As described previously for Sindbis virus and endotoxin, the animals also became hyporeactive after injection of PAA. PMID:5725320

CMV Infection in Bone Marrow and Solid Organ Transplant Patients in the Era of Antiviral Prophylaxis.

PubMed

Hebart, Holger; Jahn, Gerhard; Sinzger, Christian; Kanz, Lothar; Einsele, Hermann

2000-02-01

Recent developments in the diagnosis and therapy of cytomegalovirus (CMV) infection have helped to reduce CMV-associated morbidity and mortality following allogeneic bone marrow and solid organ transplantation. The clinical symptoms of active CMV infection and the prevalence of life-threatening CMV disease vary widely between different patient populations according to the type of transplant and the intensity of immunosuppression employed. Antiviral prophylaxis with aciclovir, valaciclovir and ganciclovir has been shown to reduce CMV infection and disease following organ transplantation. Antiviral drugs, in particular ganciclovir and foscarnet, have varying sideeffects, however, and antiviral resistance due to prolonged administration of ganciclovir and foscarnet has been reported recently. Short courses of pre-emptive antiviral therapy for documented CMV infection help to reduce the duration and sideeffects of therapy, offering an alternative strategy to antiviral prophylaxis. Studies are required to compare the efficacy and costs of antiviral prophylaxis with pre-emptive therapy.

Antiviral agents for influenza: a comparison of cost-effectiveness data.

PubMed

Lynd, Larry D; Goeree, Ron; O'Brien, Bernie J

2005-01-01

The economic burden of influenza-related illness has been estimated to be 71.3-166 billion US dollars in the US, the majority of which is attributable to indirect costs as a result of lost productivity. There are currently four antiviral drugs available for the treatment of influenza: two ion channel blockers, amantadine and rimantadine; and two neuraminidase inhibitors, zanamivir and oseltamivir. The objective of this paper was to review the studies evaluating the cost effectiveness of currently available antiviral treatment and prophylaxis management strategies for influenza. Published studies that reported both costs and effectiveness of influenza management were extracted using MEDLINE, pre-MEDLINE and EMBASE. To facilitate a broad comparison, all costs were inflated to 2003 US dollars. Fifteen studies met the inclusion criteria of the review, with 14 analyses based on decision-analytic modelling and one economic analysis performed alongside a clinical trial. Management strategies included antiviral influenza prophylaxis or vaccination, empiric treatment of suspected disease, or antiviral treatment following rapid influenza testing. Study populations included healthy adults, adults at risk of influenza-related adverse outcomes, institutionalised and non-institutionalised elderly, and children. The comparator in all studies was standard care (i.e. over-the-counter medications only), and analyses were carried out from both the societal and payer perspectives. The only dominant strategy relative to standard care was vaccination of the institutionalised elderly. All other strategies in all populations were both more costly and more effective than standard care. Depending on the population and the perspective, the incremental cost-effectiveness ratios (ICERs) for antiviral treatment strategies ranged from 5000 US dollars/QALY for amantadine in test-and-treat studies to >400,000 US dollars/QALY for zanamivir or oseltamivir treatment in children. Sensitivity analysis

Sofosbuvir and ABT-450: terminator of hepatitis C virus?

PubMed

Zeng, Qing-Lei; Zhang, Ji-Yuan; Zhang, Zheng; Wang, Li-Feng; Wang, Fu-Sheng

2013-06-07

Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with this regimen. SVR rates are approximately 80% in patients with hepatitis C virus (HCV) genotype 2, 3, 5 and 6 and 40%-50% in patients with genotype 1 and 4. Therefore, strategies to improve SVR rates have been an important issue for clinical physicians. Several direct acting antiviral agents (DAAs) have significantly higher SVR rates when combined with pegIFN-α and RBV than pegIFN-α and RBV alone. Treatments containing DAAs have several advantages over the previous SOC, including higher specificity and efficacy, shorter treatment durations, fewer side effects, and oral administration. Based on these advantages, treatment with pegIFN-α and RBV plus telaprevir or boceprevir has become the current SOC for patients with genotype 1 HCV infection. However, many patients are either not eligible for therapy or decline treatment due to coexisting relative or absolute contraindications as well as an inability to tolerate the hematological side effects and adverse events caused by the new SOC. These factors have contributed to the advent of pegIFN-α-free regimens. The newest therapeutic regimens containing sofosbuvir and ABT-450 have shown promising results. In this review, we summarize the development of anti-HCV agents and the clinical efficacy of sofosbuvir and ABT-450-based therapies as well as the potential for future HCV studies.

Comorbidities and medications of patients with chronic hepatitis C under specialist care in the UK

PubMed Central

Hudson, Benjamin; Walker, Alex J.

2017-01-01

Designing services with the capacity and expertise to meet the needs of the chronic hepatitis C (CHC) population in the era of direct acting antivirals (DAAs), and widening access to such treatments, requires detailed understanding of the characteristics and healthcare needs of the existing patient population. In this retrospective analysis of data from the National HCV Research UK Biobank between March 2012 and October 2014, the characteristics of the CHC population currently under specialist care in the UK were evaluated—with specific focus upon use of medications, adverse lifestyle choices, and comorbidities. Demographic data, risk factors for CHC acquisition, HCV genotype, liver disease status, lifestyle factors, comorbidities, and medication classes were collected. Data were analyzed by history of injecting drug use (IDU), age, and severity of liver disease. A total of 6278 patients (70.5% white; median age, 52 years) from 59 UK specialist centres were included; 59.1% of patients had acquired HCV through IDU. The prevalence of adverse lifestyle factors was significantly lower in non‐IDU compared with previous IDU or recent IDU patients. Depression was common in the previous (50.8%) and recent IDU (68.1%) groups, compared with 27.6% in non‐IDU patients. Cirrhosis was common (23.6%), and prevalence increased with age. We describe a heterogeneous, polymorbid, and aging population of CHC patients in secondary care, and demonstrate underrepresentation of injecting drug users within the current system. The implications of this present significant challenges to physicians and healthcare commissioners in designing services which are fit for purpose inthe DAA era. PMID:28480974

Hepatitis C Virus Infection Outcomes Among Immigrants to Canada: A Retrospective Cohort Analysis.

PubMed

Cooper, Curtis L; Thavorn, Kednapa; Damian, Ecaterina; Corsi, Daniel J

2017-01-01

HCV-infected immigrants contribute to the total prevalence in Canada and other developed nations. Little is known about engagement in care, access to service, and treatment outcomes in recipients of Direct Acting Antiviral (DAA) HCV therapies among immigrants living with HCV. HCV patients assessed at The Ottawa Hospital Viral Hepatitis Clinic between 2000-2016 were identified. Immigration history, race, socioeconomic status, HCV work-up, treatment and outcome data were evaluated. HCV fibrosis assessment, treatment and sustained virologic response (SVR) were compared using logistic regression. 2,335 HCV-infected patients were analyzed with 91% (2114) having data on immigration (23% immigrants). A median 16 years (Quartiles: 5, 29) passed from immigration to referral. Access to diagnostic procedures (Fibroscan/liver biopsy) was greater among immigrants compared to Canadian-born (78% vs. 68%, p = 0.001) and immigrants had an odds ratio of 1.72 (95% CI: 1.18-2.51) of receiving a FibroScan compared to Canadians after adjustment for demographic characteristics, HCV risk factors, and socioeconomic status. No differences in SVR were found between immigrants for IFN recipients. Among DAA recipients, rates of SVR were > 94% among all patients, 93% in Canadian-born and 98% among immigrants (p = 0.14). Nearly 80% of immigrants in this setting had access to fibrosis assessment which was higher than Canadian-born patients. Under half of both groups had initiated HCV therapy. Delays in accessing HCV care represent a missed opportunity to engage, treat and cure HCV patients. HCV screening and health care engagement at the time of immigration would optimize HCV care and therapeutic outcomes.

Utilization of different anti-viral mechanisms by mammalian embryonic stem cells and differentiated cells.

PubMed

Guo, Yan-Lin

2017-01-01

Embryonic stem cells (ESCs) have received tremendous attention because of their potential applications in regenerative medicine. Over the past two decades, intensive research has not only led to the generation of various types of cells from ESCs that can be potentially used for the treatment of human diseases but also led to the formation of new concepts and breakthroughs that have significantly impacted our understanding of basic cell biology and developmental biology. Recent studies have revealed that ESCs and other types of pluripotent cells do not have a functional interferon (IFN)-based anti-viral mechanism, challenging the idea that the IFN system is developed as the central component of anti-viral innate immunity in all types of cells in vertebrates. This finding also provided important insight into a question that has been uncertain for a long time: whether or not the RNA interference (RNAi) anti-viral mechanism operates in mammalian cells. An emerging paradigm is that mammals may have adapted distinct anti-viral mechanisms at different stages of organismal development; the IFN-based system is mainly used by differentiated somatic cells, while the RNAi anti-viral mechanism may be used in ESCs. This paper discusses the molecular basis and biological implications for mammals to have different anti-viral mechanisms during development.

The antiviral protein Viperin suppresses T7 promoter dependent RNA synthesis-possible implications for its antiviral activity.

PubMed

Dukhovny, Anna; Shlomai, Amir; Sklan, Ella H

2018-05-25

Viperin is a multifunctional interferon-inducible broad-spectrum antiviral protein. Viperin belongs to the S-Adenosylmethionine (SAM) superfamily of enzymes known to catalyze a wide variety of radical-mediated reactions. However, the exact mechanism by which viperin exerts its functions is still unclear. Interestingly, for many RNA viruses viperin was shown to inhibit viral RNA accumulation by interacting with different viral non-structural proteins. Here, we show that viperin inhibits RNA synthesis by bacteriophage T7 polymerase in mammalian cells. This inhibition is specific and occurs at the RNA level. Viperin expression significantly reduced T7-mediated cytoplasmic RNA levels. The data showing that viperin inhibits the bacteriophage T7 polymerase supports the conservation of viperin's antiviral activity between species. These results highlight the possibility that viperin might utilize a broader mechanism of inhibition. Accordingly, our results suggest a novel mechanism involving polymerase inhibition and provides a tractable system for future mechanistic studies of viperin.

[Research Progress on Antiviral Activity of Interferon-induced Transmembrane Proteins].

PubMed

Chen, Yongkun; Zhu, Wenfei; Shu, Yuelong

2016-03-01

Interferon-induced Transmembrane Proteins (IFITMs) were identified through small interference RNA (siRNA) screening method in 1980s. The antiviral properties of the IFITMs were firstly discovered in 1996. Recently, its antiviral effect and mechanism have become a research hotspot. Many studies have shown that IFITM can inhibit the replication of multiple pathogenic viruses, including influenza A virus (IAV), Human Immunodeficiency Virus (HIV-1), hepatitis C virus (HCV), Ebola virus (EBOV), West Nile virus and so on. IFITMs inhibit the replication of virus in the early stage of the viral life cycle, which occurred before the release of viral genomes into the cytosol. Recent studies indicate that IFITM proteins could block viral replication by mediate viral membrane fusion. However, the mechanism is still under investigation. Here we review the discovery and characterization of the IFITM proteins, elucidate their antiviral activities and the potential mechanisms.

The Antiviral Effect of Baicalin on Enterovirus 71 In Vitro

PubMed Central

Li, Xiang; Liu, Yuanyuan; Wu, Tingting; Jin, Yue; Cheng, Jianpin; Wan, Changbiao; Qian, Weihe; Xing, Fei; Shi, Weifeng

2015-01-01