Hitchings, Matt David Thomas; Grais, Rebecca Freeman
Background The 2014–6 West African Ebola epidemic highlights the need for rigorous, rapid clinical trial methods for vaccines. A challenge for trial design is making sample size calculations based on incidence within the trial, total vaccine effect, and intracluster correlation, when these parameters are uncertain in the presence of indirect effects of vaccination. Methods and findings We present a stochastic, compartmental model for a ring vaccination trial. After identification of an index case, a ring of contacts is recruited and either vaccinated immediately or after 21 days. The primary outcome of the trial is total vaccine effect, counting cases only from a pre-specified window in which the immediate arm is assumed to be fully protected and the delayed arm is not protected. Simulation results are used to calculate necessary sample size and estimated vaccine effect. Under baseline assumptions about vaccine properties, monthly incidence in unvaccinated rings and trial design, a standard sample-size calculation neglecting dynamic effects estimated that 7,100 participants would be needed to achieve 80% power to detect a difference in attack rate between arms, while incorporating dynamic considerations in the model increased the estimate to 8,900. This approach replaces assumptions about parameters at the ring level with assumptions about disease dynamics and vaccine characteristics at the individual level, so within this framework we were able to describe the sensitivity of the trial power and estimated effect to various parameters. We found that both of these quantities are sensitive to properties of the vaccine, to setting-specific parameters over which investigators have little control, and to parameters that are determined by the study design. Conclusions Incorporating simulation into the trial design process can improve robustness of sample size calculations. For this specific trial design, vaccine effectiveness depends on properties of the ring
... NIAID). /* // ** // */ Prevention Research Vaccines Microbicides Related Topics on AIDS.gov Clinical Trials Immune System 101 HIV Vaccine ... Be the Generation Last revised: 12/09/2016 AIDS.gov HIV/AIDS Basics • Federal Resources • Using New ...
Matthews, Thomas J.; Bolognesi, Dani P.
Reveals that success of discovering vaccines is far from being assured although several candidates are being tested. States that the devious nature of the virus, the lack of a good animal model for the disease, and the difficulties of clinical trials inhibit the efforts of researchers. (RT)
Pérez-Losada, Marcos; Jobes, David V.; Sinangil, Faruk; Crandall, Keith A.; Posada, David; Berman, Phillip W.
In 2003, a phase III placebo-controlled trial (VAX004) of a candidate HIV-1 vaccine (AIDSVAX B/B) was completed in 5,403 volunteers at high risk for HIV-1 infection from North America and the Netherlands. A total of 368 individuals became infected with HIV-1 during the trial. The envelope glycoprotein gene (gp120) from the HIV-1 subtype B viruses infecting 349 patients was sequenced from clinical samples taken as close as possible to the time of diagnosis, rendering a final data set of 1,047 sequences (1,032 from North America and 15 from the Netherlands). Here, we used these data in combination with other sequences available in public databases to assess HIV-1 variation as a function of vaccination treatment, geographic region, race, risk behavior, and viral load. Viral samples did not show any phylogenetic structure for any of these factors, but individuals with different viral loads showed significant differences (P = 0.009) in genetic diversity. The estimated time of emergence of HIV-1 subtype B was 1966–1970. Despite the fact that the number of AIDS cases has decreased in North America since the early 90s, HIV-1 genetic diversity seems to have remained almost constant over time. This study represents one of the largest molecular epidemiologic surveys of viruses responsible for new HIV-1 infections in North America and could help the selection of epidemiologically representative vaccine antigens to include in the next generation of candidate HIV-1 vaccines. PMID:19864468
Sheets, Rebecca L; Zhou, TieQun; Knezevic, Ivana
The clinical development of prophylactic HIV-1/AIDS vaccines is confounded by numerous scientific challenges and these in turn result in challenges to regulators reviewing clinical trial applications (CTAs). The search for an HIV-1/AIDS vaccine will only succeed through the conduct of well-designed, well-conducted and well-controlled human efficacy studies. This review summarizes relevant context in which HIV vaccines are being investigated and the six completed efficacy trials of various candidate vaccines and regimens, as well as the lessons learned from them relevant to regulatory evaluation. A companion review focuses on the scientific challenges regulators face and summarizes some current candidates in development. The lessons learned from the completed efficacy trials will enable the development of better designed, potentially more efficient efficacy trials in future. This summary, supported by the World Health Organization (WHO), is unique in that it is meant to aid regulators in understanding the valuable lessons gained from experience in the field to date.
Sheets, Rebecca L; Zhou, TieQun; Knezevic, Ivana
Clinical development of prophylactic HIV/AIDS vaccines presents many scientific challenges that result in challenges for regulators reviewing clinical trial applications (CTAs). The World Health Organization (WHO) has the responsibility to provide technical support to these regulators. The search for an HIV/AIDS vaccine will only succeed through well-designed, -conducted and -controlled human efficacy studies reviewed and approved by regulators in countries worldwide, particularly in countries where the epidemic has hit hardest, such as in sub-Saharan Africa and Asia. This review summarizes the current candidates in development and focuses on challenges regulators face when reviewing CTAs, such as the evolving landscape of "standard of prevention," trials in adolescents, adaptive trial designs, correlates of protection and their analysis, and access to successful vaccines. There are many unknowns in the field of HIV/AIDS vaccine development and often, there is not a clear right or wrong approach because of the scientific challenges described in this review. Consequently, regulators should not feel that decisions need be made in isolation, when there are many available international collaborative efforts and opportunities to seek expert advice. The WHO provides many such opportunities and support to regulators across the globe.
Lu, Shan; Grimes Serrano, Jill M.; Wang, Shixia
A major hurdle in the development of a global HIV-1 vaccine is viral diversity. For close to three decades, HIV vaccine development has focused on either the induction of T cell immune responses or antibody responses, and only rarely on both components. After the failure of the STEP trial, the scientific community concluded that a T cell-based vaccine would likely not be protective if the T cell immune responses were elicited against only a few dominant epitopes. Similarly, for vaccines focusing on antibody responses, one of the main criticisms after VaxGen’s failed Phase III trials was on the limited antigen breadth included in the two formulations used. The successes of polyvalent vaccine approaches against other antigenically variable pathogens encourage implementation of the same approach for the design of HIV-1 vaccines. A review of the existing HIV-1 vaccination approaches based on the polyvalent principle is included here to provide a historical perspective for the current effort of developing a polyvalent HIV-1 vaccine. Results summarized in this review provide a clear indication that the polyvalent approach is a viable one for the future development of an effective HIV vaccine. PMID:21054250
Girard, M P
After over 20 years of research and development (R&D) and more than 85 clinical trials using various candidate vaccines, there has been little progress in research for a vaccine against HIV/AIDS. This disappointing result raises serious doubts as to whether an effective HIV/AIDS vaccine will be available within a reasonable time frame. There are three main obstacles. The first is that the virus promptly enters into the genome of effector memory T-cells that then constitute an infection reservoir from which the virus cannot be dislodged. The second obstacle involves the genetic hyper-variability of the virus that can easily dodge host immune defenses by mutating. The third obstacle is that we are still unable to induce antibodies able to neutralize wild strains of the virus and block infection early. Current vaccines are designed to induce cellular immune responses - mostly of the CD8+ cytotoxic T cell (CTL) type - in the hope of limiting the clinical consequences of infection by reducing the rate of virus multiplication and decreasing virus load in recently infected persons. This strategy has led to development of numerous live attenuated vaccines using a wide variety of viral or bacterial vectors. These vaccines are currently being tested either singly or in various prime-boost combinations using several of these vaccines or DNA vaccines. The efficacy of these vaccination techniques in humans remains to be determined.
During the 13th International AIDS Conference, the International AIDS Vaccine Initiative (IAVI) issued a detailed working agenda, ¿AIDS Vaccines for World: Preparing Now to Assure Access.¿ The report provides an overview of vaccine economics and concludes that the existing 15-year delay in introducing vaccines to developing countries constitutes a colossal public health failure. Hence, it calls for specific changes in the way vaccines are produced, licensed, priced, purchased, and distributed, and includes a five-point action plan for immediate implementation. To this effect, IAVI proposes a program of unprecedented global collaboration in order to assure global access. This collaboration is a firm commitment from richer nations to purchase vaccines for use in hard-hit developing countries. The Initiative also calls for the tiered pricing of new vaccines so that poorer countries can sharply lower prices than industrialized countries. Moreover, IAVI proposes the creation of an international panel of experts to monitor HIV vaccine trials.
Alter, Galit; Ananworanich, Jintanat; Pantophlet, Ralph; Rybicki, Ed P; Buonaguro, Luigi
The "AIDS Vaccine 2008" Conference was held in Cape Town, South Africa (October 13 to 16, 2008) and organized, under the aegis of the Global HIV Vaccine Enterprise, by Dr. Lynn Morris (Chair of the Conference) National Institute of Communicable Diseases; Dr. Koleka Mlisana from CAPRISA, University KwaZulu-Natal, Durban, Dr. Glenda Gray from Perinatal HIV Research Unit, University Witwatersrand, Johannesburg and Dr. Carolyn Williamson from Institute of Infectious Diseses. and Molecular Medicine, UCT, Cape Town (Co-Chairs of the Conference). Since the first AIDS Vaccine conference, organized in Paris in 2000, this was the first time it was held outside of the U.S. and Europe, and involved nearly 1,000 participants. Besides three Plenary Sessions with ten state-of-the-art plenary lectures and one Keynote Lecture given by Dr. A.S. Fauci (Director of NIAID, NIH, USA), the Conference was organized in nine oral sessions, four poster discussion groups covering a wide spectrum of scientific information relating to HIV vaccine research and development. Moreover three Symposia, two Special Sessions, one Roundtable as well as two Debates were held, the latter focusing on current controversial topics. The conference opening was memorable for a number of reasons: among these was the presence of South Africa's new Minister of Health, Barbara Hogan who, in her first speech in a major forum as a senior member of the SA Government, affirmed that HIV causes AIDS, and that the search for a vaccine is of paramount importance to SA and the rest of the world. A scientific summary of the Conference is reported in the present article, divided into four major topics: (1) vaccine concepts and design; (2) T-cell immunology and innate immunity; (3) B-cell immunology, neutralizing antibodies and mucosal immunology; and (4) clinical trials.
... and effective in people. What is an HIV/AIDS clinical trial? HIV/AIDS clinical trials help researchers ... to HIV Can anyone participate in an HIV/AIDS clinical trial? It depends on the study. Some ...
Chin'ombe, Nyasha; Ruhanya, Vurayai
HIV/AIDS is an important public health problem globally. An affordable, easy-to-deliver and protective HIV vaccine is therefore required to curb the pandemic from spreading further. Recombinant Salmonella bacteria can be harnessed to vector HIV antigens or DNA vaccines to the immune system for induction of specific protective immunity. These are capable of activating the innate, humoral and cellular immune responses at both mucosal and systemic compartments. Several studies have already demonstrated the utility of live recombinant Salmonella in delivering expressed foreign antigens as well as DNA vaccines to the host immune system. This review gives an overview of the studies in which recombinant Salmonella bacteria were used to vector HIV/AIDS antigens and DNA vaccines. Most of the recombinant Salmonella-based HIV/AIDS vaccines developed so far have only been tested in animals (mainly mice) and are yet to reach human trials.
Batson, A.; Ainsworth, M.
The development of vaccines for the prevention of AIDS, malaria, tuberculosis, and other diseases requires both public and private investment. Private investment, however, has been far lower than might have been hoped, given the massive human toll of these diseases, particularly in the poorest countries. With a view to understanding this situation and exploring potential solutions, the World Bank AIDS Vaccine Task Force commissioned a study on the perspectives of the biotechnology, vaccine, and pharmaceutical industries regarding investment in research and development work on an AIDS vaccine. It was found that different obstacles to the development of an AIDS vaccine arose during the product development cycle. During the earlier phases, before obtaining proof of product, the principal barriers were scientific. The lack of consensus on which approach was likely to be effective increased uncertainty and the risks associated with investing in expensive clinical trials. The later phases, which involved adapting, testing, and scaling up production for different populations, were most influenced by market considerations. In order to raise the levels of private research and development in an AIDS vaccine there will probably have to be a combination of push strategies, which reduce the cost and scientific risk of investment, and pull strategies, which guarantee a market. PMID:11545328
Excler, Jean-Louis; Rida, Wasima; Priddy, Frances; Gilmour, Jill; McDermott, Adrian B.; Kamali, Anatoli; Anzala, Omu; Mutua, Gaudensia; Sanders, Eduard J.; Koff, Wayne; Berkley, Seth
Abstract While the long-term goal is to develop highly effective AIDS vaccines, first generation vaccines may be only partially effective. Other HIV prevention modalities such as preexposure prophylaxis with antiretrovirals (PrEP) may have limited efficacy as well. The combined administration of vaccine and PrEP (VAXPREP), however, may have a synergistic effect leading to an overall benefit that is greater than the sum of the individual effects. We propose two test-of-concept trial designs for an AIDS vaccine plus oral or topical ARV. In one design, evidence that PrEP reduces the risk of HIV acquisition is assumed to justify offering it to all participants. A two-arm study comparing PrEP alone to VAXPREP is proposed in which 30 to 60 incident infections are observed to assess the additional benefit of vaccination on risk of infection and setpoint viral load. The demonstrated superiority of VAXPREP does not imply vaccine alone is efficacious. Similarly, the lack of superiority does not imply vaccine alone is ineffective, as antagonism could exist between vaccine and PrEP. In the other design, PrEP is assumed not to be in general use. A 2 × 2 factorial design is proposed in which high-risk individuals are randomized to one of four arms: placebo vaccine given with placebo PrEP, placebo vaccine given with PrEP, vaccine given with placebo PrEP, or VAXPREP. Between 60 and 210 infections are required to detect a benefit of vaccination with or without PrEP on risk of HIV acquisition or setpoint viral load, with fewer infections needed when synergy is present. PMID:21043994
Tang, Xian; Chen, Zhiwei
It is well known that mucosal tissues contain the largest surface area of the human body and are the front line of natural host defense against various pathogens. In fact, more than 80% of infectious disease pathogens probably gain entry into the susceptible human hosts through open mucosal surfaces. Human immunodeficiency virus type one (HIV-1), a mainly sexually transmitted virus, also primarily targets the vaginal and gastrointestinal mucosa as entry sites for viral transmission, seeding, replication and amplification. Since HIV-1 establishes its early replication in vaginal or rectal mucosal tissues, the induction of sufficient mucosal immunity at the initial site of HIV-1 transmission becomes essential for a protective vaccine. However, despite the fact that current conventional vaccine strategies have remained unsuccessful in preventing HIV-1 infection, sufficient financial support and resources have yet to be given to develop a vaccine able to elicit protective mucosal immunity against sexual transmissions. Interestingly, Chinese ancestors invented variolation through intranasal administration about one thousand years ago, which led to the discovery of a successful smallpox vaccine and the final eradication of the disease. It is the hope for all mankind that the development of a mucosal AIDS vaccine will ultimately help control the AIDS pandemic. In order to discover an effective mucosal AIDS vaccine, it is necessary to have a deep understanding of mucosal immunology and to test various mucosal vaccination strategies. PMID:21994611
... https://medlineplus.gov/news/fullstory_162715.html Ebola Vaccine Appears Very Effective in Trial Drug manufacturer says ... Dec. 23, 2016 (HealthDay News) -- An experimental Ebola vaccine was highly effective against the deadly virus in ...
Yamamoto, Janet K.; Sanou, Missa P.; Abbott, Jeffrey R.; Coleman, James K.
Feline immunodeficiency virus (FIV) discovered in 1986 is a lentivirus that causes AIDS in domestic cats. FIV is classified into five subtypes (A–E), and all subtypes and circulating intersubtype recombinants have been identified throughout the world. A commercial FIV vaccine, consisting of inactivated subtype-A and –D viruses (Fel-O-Vax FIV, Fort Dodge Animal Health), was released in the United States in 2002. The United States Department of Agriculture approved the commercial release of Fel-O-Vax FIV based on two efficacy trials using 105 laboratory cats and a major safety trial performed on 689 pet cats. The prototype and commercial FIV vaccines had broad prophylactic efficacy against global FIV subtypes and circulating intersubtype recombinants. The mechanisms of cross-subtype efficacy are attributed to FIV-specific T-cell immunity. Findings from these studies are being used to define the prophylactic epitopes needed for an HIV-1 vaccine for humans. PMID:20210778
Voronin, Yegor; Phogat, Sanjay
The symposium "HIV/AIDS: Vaccines and Alternate Strategies for Treatment and Prevention" brought together HIV vaccine researchers to discuss the latest developments in the field. From basic discoveries in virus diversity and mechanisms of neutralization by antibodies to nonhuman primate research and clinical trials of vaccine candidates in volunteers, scientists are making great strides in understanding the mechanisms that may protect against HIV and pathways to achieve this protection through vaccination.
... Harvoni Hepatitis A and Hepatitis B (Recombinant) Vaccine Hepatitis B Vaccine Human Papillomavirus 9 Valent (Types 6, 11, 16, ... Chagas Disease Coccidioidomycosis Cryptococcosis Cryptosporidiosis Cytomegalovirus ... Circumcision Microbicides Post-Exposure Prophylaxis (PEP) Pre- ...
Lubaroff, David M
This review presents important information about the current state of the art for vaccine immunotherapy of prostate cancer. It includes important preclinical research for each of the important prostate cancer vaccines to have reached clinical trials. To date, the only prostate cancer vaccine that has completed Phase III trials and has been approved and licensed by the US FDA is Sipuleucel-T, which immunizes patients against the prostate-associated antigen prostatic acid phosphatase. The benefits and concerns associated with the vaccine are presented. A current Phase III trial is currently underway using the vaccinia-based prostate-specific antigen vaccine Prostvac-TRICOM. Other immunotherapeutic vaccines in trials include the Ad/prostate-specific antigen vaccine Ad5-prostate-specific antigen and the DNA/prostatic acid phosphatase vaccine. A cellular vaccine, GVAX, has been in clinical trials but has not seen continuous study. This review also delves into the multiple immune regulatory elements that must be overcome in order to obtain strong antitumor-associated antigen immune responses capable of effectively destroying prostate tumor cells.
Chin'ombe, Nyasha; Ruhanya, Vurayai
More than decades have already elapsed since human immunodeficiency virus (HIV) was identified as the causative agent of acquired immunodeficiency syndrome (AIDS). The HIV has since spread to all parts of the world with devastating effects. In sub-saharan Africa, the HIV/AIDS epidemic has reached unprecedented proportions. Safe, effective and affordable HIV/AIDS vaccines for Africans are therefore urgently needed to contain this public health problem. Although, there are challenges, there are also scientific opportunities and strategies that can be exploited in the development of HIV/AIDS vaccines for Africa. The recent RV144 Phase III trial in Thailand has demonstrated that it is possible to develop a vaccine that can potentially elicit modest protective immunity against HIV infection. The main objective of this review is to outline the key scientific opportunities, challenges and strategies in HIV/AIDS vaccine development in Africa. PMID:26185576
Chin'ombe, Nyasha; Ruhanya, Vurayai
More than decades have already elapsed since human immunodeficiency virus (HIV) was identified as the causative agent of acquired immunodeficiency syndrome (AIDS). The HIV has since spread to all parts of the world with devastating effects. In sub-saharan Africa, the HIV/AIDS epidemic has reached unprecedented proportions. Safe, effective and affordable HIV/AIDS vaccines for Africans are therefore urgently needed to contain this public health problem. Although, there are challenges, there are also scientific opportunities and strategies that can be exploited in the development of HIV/AIDS vaccines for Africa. The recent RV144 Phase III trial in Thailand has demonstrated that it is possible to develop a vaccine that can potentially elicit modest protective immunity against HIV infection. The main objective of this review is to outline the key scientific opportunities, challenges and strategies in HIV/AIDS vaccine development in Africa.
The search for an AIDS (acquired immune deficiency syndrome) vaccine is truly a global effort, with university laboratories, biotech firms, pharmaceutical companies, nonprofit research organizations, hospitals, and clinics all working together to develop an effective vaccine as quickly as possible. The International AIDS Vaccine Initiative (IAVI)…
Corey, Lawrence; Nabel, Gary J; Dieffenbach, Carl; Gilbert, Peter; Haynes, Barton F; Johnston, Margaret; Kublin, James; Lane, H Clifford; Pantaleo, Giuseppe; Picker, Louis J; Fauci, Anthony S
Developing a vaccine against the human immunodeficiency virus (HIV) poses an exceptional challenge. There are no documented cases of immune-mediated clearance of HIV from an infected individual, and no known correlates of immune protection. Although nonhuman primate models of lentivirus infection have provided valuable data about HIV pathogenesis, such models do not predict HIV vaccine efficacy in humans. The combined lack of a predictive animal model and undefined biomarkers of immune protection against HIV necessitate that vaccines to this pathogen be tested directly in clinical trials. Adaptive clinical trial designs can accelerate vaccine development by rapidly screening out poor vaccines while extending the evaluation of efficacious ones, improving the characterization of promising vaccine candidates and the identification of correlates of immune protection.
Benenson, A. S.; Joseph, P. R.; Oseasohn, R. O.
Double-blind controlled cholera-vaccine trials were carried out in rural East Pakistan in 1963 and 1964. Pretrial studies indicated that a whole-cell cholera vaccine of high mouse protective potency, at a dose of 0.5 ml, produced an antibody response and reaction pattern consistent with use in such trials. A purified Ogawa antigen, given at a dose of 100 μg, elicited no adverse reactions and evoked both agglutinating and vibriocidal antibodies against both Inaba and Ogawa test suspensions. In the field, adverse reactions to the cholera vaccines occurred primarily among adults and were observed with both the whole-cell preparation and the purified Ogawa antigen. At the dose used in the field trials (0.4 ml), the reactions elicited by the whole-cell vaccine were acceptable to the population and no more marked than those following the locally prepared typhoid-paratyphoid vaccine. Delayed reactions to the whole-cell cholera vaccine were observed beginning 4 to 7 days after the vaccine was administered; the bulk of them (60%) did not interfere with work at any time; all resolved promptly; and none developed fluctuation or was associated with abscess formation. PMID:5302328
Therapeutic cancer vaccines have characteristics that require a new paradigm for phase I and phase II clinical development. Effective development plans may take advantage of some of the following observations: Dose ranging safety trials are not appropriate for many cancer vaccines. Dose ranging trials to establish an optimal biologic dose are often not practical. We have presented an efficient design of Korn et al. (4) to identify an immunogenic dose. Vaccine efficacy can be efficiently evaluated with tumor response as endpoint utilizing a two stage design with only 9 patients in the first stage. If no partial or complete responses are observed in the initial 9 patients, accrual to the trial is terminated. Optimization of vaccine delivery by comparing results of single arm phase II studies using immunological response as endpoint is problematic because of assay variation and potential non-comparability of patients in different studies. Randomized screening studies can be used to efficiently optimize vaccine immunogenicity. Efficiency in use of patients depends on having assay variation and inter-patient variability small relative to the difference in immunogenicity to be detected. Phase II studies using time to progression as endpoint are most interpretable if they employ randomized designs with a no-vaccine control group. Such designs may use an inflated type 1 error rate, and need not be prohibitively large if patients with rapidly progressive disease are studied. Interim monitoring plans may effectively limit the size of the trials by terminating accrual early when results are not consistent with the targeted improvement.
Kublin, James G; Morgan, Cecilia A; Day, Tracey A; Gilbert, Peter B; Self, Steve G; McElrath, M Juliana; Corey, Lawrence
The HIV Vaccine Trials Network (HVTN) is an international collaboration of scientists and educators facilitating the development of HIV/AIDS preventive vaccines. The HVTN conducts all phases of clinical trials, from evaluating experimental vaccines for safety and immunogenicity, to testing vaccine efficacy. Over the past decade, the HVTN has aimed to improve the process of designing, implementing and analyzing vaccine trials. Several major achievements include streamlining protocol development while maintaining input from diverse stakeholders, establishing a laboratory program with standardized assays and systems allowing for reliable immunogenicity assessments across trials, setting statistical standards for the field and actively engaging with site communities. These achievements have allowed the HVTN to conduct over 50 clinical trials and make numerous scientific contributions to the field. PMID:23243491
A 6-month clinical trial in the Philippines sought to determine the efficacy of coconut oil and of "monolaurin," a coconut oil byproduct, in killing HIV by breaking down its coating. This research is based on the theory that medium-chain fatty acids, like monolaurin, can have this effect on certain viruses. The trial involves 12 women and 3 men in the early stage of HIV infection. 10 patients will take different doses of monolaurin, and 5 will consume coconut oil. It is hypothesized that the regimen will lead to higher CD4 counts and a lower viral load. The trial was almost abandoned because it received only lukewarm approval from the Health Secretary.
Fisher, Celia B.
This research used open-ended and true-false questions to assess the preparedness of 96 ethnically diverse, economically and socially marginalized adult street drug users to consent to participate in HIV vaccine trials (HVT). Specific areas of consent vulnerability included misconceptions about: (1) the recuperative value and risk of vaccines in general; (2) the presence of the HIV virus within the vaccine and the possibility of contracting or transmitting HIV as a consequence of participation; (3) inclusion criteria and experimental blinds; and (4) distrust in the medical and research establishments. A brief HVT lesson administered to 30 participants was effective in correcting specific HVT knowledge misperceptions and increasing certain, but not all areas of HVT trust. Assessment of post-lesson responses to ethics-relevant questions provides information on respondents' attitudes toward AIDS safe behavior, research risks and benefits, monetary compensation, and willingness to participate. Implications for enhancing informed consent for HVT involving active drug users are discussed. PMID:20569151
Background Industry partnerships can help leverage resources to advance HIV/AIDS vaccine research, service delivery, and policy advocacy goals. This often involves capacity building for international and local non-governmental organizations (NGOs). International volunteering is increasingly being used as a capacity building strategy, yet little is known about how corporate volunteers help to improve performance of NGOs in the fight against HIV/AIDS. Methods This case study helps to extend our understanding by analyzing how the Pfizer Global Health Fellows (GHF) program helped develop capacity of the International AIDS Vaccine Initiative (IAVI), looking specifically at Fellowship activities in South Africa, Kenya, and Uganda. From 2005–2009, 8 Pfizer GHF worked with IAVI and local research centers to strengthen capacity to conduct and monitor vaccine trials to meet international standards and expand trial activities. Data collection for the case study included review of Fellow job descriptions, online journals, evaluation reports, and interviews with Fellows and IAVI staff. Qualitative methods were used to analyze factors which influenced the process and outcomes of capacity strengthening. Results Fellows filled critical short-term expert staffing needs at IAVI as well as providing technical assistance and staff development activities. Capacity building included assistance in establishing operating procedures for the start-up period of research centers; training staff in Good Clinical Practice (GCP); developing monitoring capacity (staff and systems) to assure that centers are audit-ready at all times; and strategic planning for data management systems. Factors key to the success of volunteering partnerships included similarities in mission between the corporate and NGO partners, expertise and experience of Fellows, and attitudes of partner organization staff. Conclusion By developing standard operating procedures, ensuring that monitoring and regulatory
Lindegger, Graham; Quayle, Michael; Ndlovu, Moses
This study forms part of the preparation of communities for HIV-preventive vaccine trials in South Africa. On the basis of the assumption that attitudes to any HIV vaccine or vaccine trials will partly be influenced by experiences of vaccination in general, this study aimed to investigate knowledge of, attitudes to, and experiences of vaccination…
Vacchelli, Erika; Martins, Isabelle; Eggermont, Alexander; Fridman, Wolf Hervé; Galon, Jerome; Sautès-Fridman, Catherine; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo
Prophylactic vaccination constitutes one of the most prominent medical achievements of history. This concept was first demonstrated by the pioneer work of Edward Jenner, dating back to the late 1790s, after which an array of preparations that confer life-long protective immunity against several infectious agents has been developed. The ensuing implementation of nation-wide vaccination programs has de facto abated the incidence of dreadful diseases including rabies, typhoid, cholera and many others. Among all, the most impressive result of vaccination campaigns is surely represented by the eradication of natural smallpox infection, which was definitively certified by the WHO in 1980. The idea of employing vaccines as anticancer interventions was first theorized in the 1890s by Paul Ehrlich and William Coley. However, it soon became clear that while vaccination could be efficiently employed as a preventive measure against infectious agents, anticancer vaccines would have to (1) operate as therapeutic, rather than preventive, interventions (at least in the vast majority of settings), and (2) circumvent the fact that tumor cells often fail to elicit immune responses. During the past 30 y, along with the recognition that the immune system is not irresponsive to tumors (as it was initially thought) and that malignant cells express tumor-associated antigens whereby they can be discriminated from normal cells, considerable efforts have been dedicated to the development of anticancer vaccines. Some of these approaches, encompassing cell-based, DNA-based and purified component-based preparations, have already been shown to exert conspicuous anticancer effects in cohorts of patients affected by both hematological and solid malignancies. In this Trial Watch, we will summarize the results of recent clinical trials that have evaluated/are evaluating purified peptides or full-length proteins as therapeutic interventions against cancer.
Watermeyer, Jennifer; Penn, Claire
South Africa is a multilingual, multicultural context that poses communication challenges to health professionals. In a clinical trial, information must be thoroughly understood by participants in order for consent to be informed. Unfortunately, this is not always the case. This pilot study aimed to identify communication successes and breakdowns…
The International AIDS Vaccine Initiative (IAVI) received a $25 million five-year grant from Bill and Melinda Gates through the William H. Gates Foundation. This is the largest gift seen in the AIDS epidemic, and will allow IAVI to more than double vaccine development efforts. IAVI is currently developing two potential vaccines, hopes to study three others, and is working with the business community to insure that a successful vaccine is affordable in developing countries. With 16,000 new infections occurring daily, a vaccine is seen as the most effective way to stop the epidemic. The William H. Gates Foundation had donated $1.5 million to IAVI and $100 million for programs to speed the delivery of vaccines to children in poor countries. Internet addresses are included for both IAVI and the William H. Gates Foundation.
Pinkerton, Steven D.; Abramson, Paul R.
Biomedical, logistic, economic, social, and psychosocial issues related to the successful distribution and use of a vaccine for human immunodeficiency virus (HIV) are reviewed. A mathematical model is introduced as an aid in conceptualizing these issues. The HIV vaccine should be seen as an adjunct to behavioral modification. (SLD)
Since the discovery of simian immunodeficiency viruses (SIV) causing AIDS-like diseases in Asian macaques, non-human primates (NHP) have played an important role in AIDS vaccine research. A multitude of vaccines and immunization approaches have been evaluated, including live attenuated viruses, DNA vaccines, viral and bacterial vectors, subunit proteins, and combinations thereof. Depending on the particular vaccine and model used, varying degrees of protection have been achieved, including prevention of infection, reduction of viral load, and amelioration of disease. In a few instances, potential safety concerns and vaccine-enhanced pathogenicity have also been noted. In the past decade, sophisticated methodologies have been developed to define the mechanisms of protective immunity. However, a clear road map for HIV vaccine development has yet to emerge. This is in part because of the intrinsic nature of the surrogate model and in part because of the improbability of any single model to fully capture the complex interactions of natural HIV infection in humans. The lack of standardization, the limited models available, and the incomplete understanding of the immunobiology of NHP contribute to the difficulty to extrapolate findings from such models to HIV vaccine development. Until efficacy data become available from studies of parallel vaccine concepts in humans and macaques, the predictive value of any NHP model remains unknown. Towards this end, greater appreciation of the utility and limitations of the NHP model and further developments to better mimic HIV infection in humans will likely help inform future AIDS vaccine efforts. PMID:15975024
... medlineplus.gov/news/fullstory_163137.html Genital Herpes Vaccine Shows Promise in Animal Trials Two-pronged approach ... THURSDAY, Jan. 19, 2017 (HealthDay News) -- A new vaccine for genital herpes could be nearing human clinical ...
Ferrantelli, Flavia; Buttò, Stefano; Cafaro, Aurelio; Wahren, Britta; Ensoli, Barbara
The need for an effective HIV/AIDS vaccine is imperative to halt a pandemic that involves more than 40 million individuals worldwide as of 2005 and is causing enormous socio-economic losses, especially in developing countries (DC). The overall failure of more than two decades of HIV vaccine research justifies the demands for a concerted effort for the rapid development of new and efficacious vaccines against HIV/AIDS. In this context, building international collaborative networks is a must for speeding up scientific research and optimizing the use of funding in a synergistic fashion, as resources for HIV/AIDS are limited and do not involve most of the biggest Pharmas that are more interested in drug discovery. The AIDS Vaccine Integrated Project (AVIP) consortium is an example of synergistic partnership of international European Union and DC experts with a common research goal. AVIP is a European Commission-funded (FP-6), consortium-based, 5-year program directed to the fast development of new HIV/AIDS vaccine candidates to be tested in phase I clinical trials in Europe for future advancement to phase II/III testing in DC. To ensure their rapid development, AVIP novel combined vaccines include both regulatory and structural HIV antigens, which have already been tested, as single components, in phase I clinical trials. In particular, such combination vaccines may be superior to earlier vaccine candidates, the vast majority of which are based only on either structural or regulatory HIV products. In fact, the generation of immune responses to both types of viral antigens expressed either early (regulatory products) or late (structural products) during the viral life cycle can maximize immune targeting of both primary or chronic viral infection. Further, the rational design of combined vaccines allows exploitation of immunomodulatory functions of HIV regulatory proteins, which can improve immunity against structural vaccine components. The building of the AVIP
Shedlock, Devon J; Silvestri, Guido; Weiner, David B
Rhesus macaques are an important animal model for the study of human disease and the development of vaccines against HIV and AIDS. HIV vaccines have been benchmarked in rhesus macaque preclinical challenge studies using chimeric viruses made up of parts of HIV and simian immunodeficiency viruses. However, the lack of efficacy in a recent clinical trial calls for a re-evaluation of the scientific assumptions regarding the predictive value of using data generated from rhesus macaques as a 'gatekeeper' for the advancement of candidate vaccines into the clinic. In this context, there is significant consensus among HIV vaccinologists that next-generation HIV vaccines must generate 'better' immunity in rhesus macaques than clinically unsuccessful vaccines generated using validated assays. Defining better immunity is the core challenge of HIV vaccine development in this system and is the focus of this Review.
Glickman, L T; Appel, M J
Two field trials were conducted during periods of endemic (summer) and epizootic (winter) canine infectious tracheobronchitis activity to evaluate the efficacy of three intranasal vaccines in a closed commercial beagle breeding kennel. A trivalent vaccine containing Bordetella bronchiseptica, canine parainfluenza, and canine adenovirus-2 was administered at 3 weeks of age. The vaccine was 71.2% and 81.8% effective in decreasing the incidence of coughing during the winter and summer trials, respectively. The number of deaths was lower in each of the vaccine groups than in the placebo groups. No adverse reactions were observed with any of the intranasal vaccines.
Noazin, Sassan; Modabber, Farrokh; Khamesipour, Ali; Smith, Peter G; Moulton, Lawrence H; Nasseri, Kiumarss; Sharifi, Iraj; Khalil, Eltahir A G; Bernal, Ivan Dario Velez; Antunes, Carlos M F; Kieny, Marie Paule; Tanner, Marcel
First generation candidate vaccines against leishmaniasis, prepared using inactivated whole parasites as their main ingredient, were considered as promising because of their relative ease of production and low cost. These vaccines have been the subject of many investigations over several decades and are the only leishmaniasis vaccine candidates which have undergone phase 3 clinical trial evaluation. Although the studies demonstrated the safety of the vaccines and several studies showed reasonable immunogenicity and some indication of protection, an efficacious prophylactic vaccine is yet to be identified. Despite this overall failure, these trials contributed significantly to increasing knowledge on human leishmaniasis immunology. To provide a collective view, this review discusses the methods and findings of field efficacy trials of first generation leishmaniasis vaccine clinical trials conducted in the Old and New Worlds.
Ellis, R D; Hatherill, M; Tait, D; Snowden, M; Churchyard, G; Hanekom, W; Evans, T; Ginsberg, A M
A recent trial of a leading tuberculosis (TB) vaccine candidate in 3000 South African infants failed to show protection over that from BCG alone, and highlights the difficulties in clinical development of TB vaccines. Progression of vaccine candidates to efficacy trials against TB disease rests on demonstration of safety and immunogenicity in target populations and protection against challenge in preclinical models, but immunologic correlates of protection are unknown, and animal models may not be predictive of results in humans. Even in populations most heavily affected by TB the sample sizes required for Phase 2b efficacy trials using TB disease as an endpoint are in the thousands. Novel clinical trial models have been developed to evaluate candidate TB vaccines in selected populations using biologically relevant outcomes and innovative statistical approaches. Such proof of concept studies can be used to more rationally select vaccine candidates for advancement to large scale trials against TB disease.
Immunoinformatics is an emergent branch of informatics science that long ago pullulated from the tree of knowledge that is bioinformatics. It is a discipline which applies informatic techniques to problems of the immune system. To a great extent, immunoinformatics is typified by epitope prediction methods. It has found disappointingly limited use in the design and discovery of new vaccines, which is an area where proper computational support is generally lacking. Most extant vaccines are not based around isolated epitopes but rather correspond to chemically-treated or attenuated whole pathogens or correspond to individual proteins extract from whole pathogens or correspond to complex carbohydrate. In this chapter we attempt to review what progress there has been in an as-yet-underexplored area of immunoinformatics: the computational discovery of whole protein antigens. The effective development of antigen prediction methods would significantly reduce the laboratory resource required to identify pathogenic proteins as candidate subunit vaccines. We begin our review by placing antigen prediction firmly into context, exploring the role of reverse vaccinology in the design and discovery of vaccines. We also highlight several competing yet ultimately complementary methodological approaches: sub-cellular location prediction, identifying antigens using sequence similarity, and the use of sophisticated statistical approaches for predicting the probability of antigen characteristics. We end by exploring how a systems immunomics approach to the prediction of immunogenicity would prove helpful in the prediction of antigens. PMID:21067543
Erves, Jennifer Cunningham; Mayo-Gamble, Tilicia L; Hull, Pamela C; Duke, Lauren; Miller, Stephania T
Approximately one-quarter of human papillomavirus (HPV) infections are acquired by adolescents, with a higher burden among racial/ethnic minorities. However, racial/ethnic minorities have been underrepresented in previous HPV vaccine trials. Ongoing and future HPV vaccine optimization trials would benefit from racially- and ethnically-diverse sample of adolescent trial participants. This study examined factors influencing parental willingness to consent to their adolescents' participation in HPV vaccine clinical trials and tested for possible racial differences. A convenience sample of parents of adolescents (N = 256) completed a cross-sectional survey. Chi square analyses were used to assess racial differences in parental HPV vaccine awareness and intentions and willingness to consent to their child participating in an HPV vaccine clinical trial. Ordinal logistic regression was used to identify factors associated with willingness. Approximately 47% of parents were willing to allow their adolescent to participate in HPV vaccine clinical trials (30.7% African American and 48.3% Caucasian, p = .081). African Americans had lower HPV vaccine awareness (p = .006) but not lower intentions to vaccinate (p = .086). Parental willingness was positively associated with the following variables: Child's age (p < .039), Perceived Advantages of HPV Vaccination for Adolescents (p = .002), Parental Trust in Medical Researchers (p < .001), and Level of Ease in Understanding Clinical Trial Information (p = .010). Educating parents about the advantages of HPV vaccines for younger adolescents using low-literacy educational materials and building trust between parents and researchers may increase parental willingness to consent to adolescent participation in HPV vaccine clinical trials.
Zverev, V V; Katlinskiĭ, A V; Kostinov, M P; Zhirova, S N; Erofeeva, M K; Stukova, M A; Korovkin, S A; Mel'nikov, S Ia; Semchenko, A V; Mironov, A N
Scientic-production association "Microgen" has finished 1st phase of clinical trials of candidate vaccines against avian influenza in order to assess their reactogenicity, safety, and immunogenicity. Two vaccines constructed from NIBRG-14 vaccine strain [A/Vietnam/1 194/2004 (H5N1)], obtained from World Health Organization, were studied: "OrniFlu" (inactivated subunit influenza vaccine adsorbed on aluminium hydroxide) and inactivated polymer-subunit influenza vaccine with polyoxydonium (IPSIV). Clinical trial of the vaccines with different quantity of antigen (15, 30, and 45 mcg of H5N1 virus hemagglutinin) was carried out in Influenza Research Institute (St. Petersburg) and in Mechnikov Research Institute of Vaccines and Sera (Moscow). Analysis of results allowed to conclude that both vaccines were safe, well tolerated and characterized by low reactogenicity. Two-doses vaccination schedule was needed to meet required seroconversion and seroprotection rates (> or =1:40 in > or =70% of vaccinated volunteers). "Orni-Flu" vaccine containing 15 mcg of hemagglutinin and optimal quantity of aluminium hydroxide (0.5 mg) in one dose as well as IPSIV containing 45 mcg of hemagglutinin and 0.75 mg of polyoxydonium in one dose were most immunogenic after 2 doses - seroprotection rates in microneutralization assay were 72.2% and 77.0% respectively. Marked influence of aluminium hydroxide content on immunogenicity of the "OrniFlu" vaccine was confirmed in the study. Optimal quantity of adjuvant was 0.5 mg per dose. According to basic concept of vaccine development, preference is given to vaccine that under minimal quantity of antigen induces sufficient specific immune response and is safe in volunteers. "OrniFlu" vaccine containing 15 mcg of H5N1 virus hemagglutinin and optimal quantity of aluminium hydroxide (0.5 mg) corresponded to these requirements that allowed researchers to recommend it for clinical trials of 2nd phase.
Chakrabarti, B K; Maitra, R K; Ma, X Z; Kestler, H W
The recent discovery of long term AIDS nonprogressors who harbor nef-attenuated HIV suggests that a naturally occurring live vaccine for AIDS may already exist. Animal models have shown that a live vaccine for AIDS, attenuated in nef, is the best candidate vaccine. There are considerable risks, real and perceived, with the use of live HIV vaccines. We have introduced a conditional lethal genetic element into HIV-1 and simian immunodeficiency virus (SIV) molecular clones deleted in nef. The antiviral strategy we employed targets both virus replication and the survival of the infected cell. The suicide gene, herpes simplex virus thymidine kinase (tk), was expressed and maintained in HIV over long periods of time. Herpes simplex virus tk confers sensitivity to the antiviral activity of acyclic nucleosides such as ganciclovir (GCV). HIV-tk and SIV-tk replication were sensitive to GCV at subtoxic concentrations, and virus-infected cells were eliminated from tumor cell lines as well as primary cell cultures. We found the HIV-tk virus to be remarkably stable even after being cultured in media containing a low concentration of GCV and then challenged with the higher dose and that while GCV resistant escape mutants did arise, a significant fraction of the virus remained sensitive to GCV. Images Fig. 1 Fig. 5 PMID:8790413
Day, Tracey A.; Kublin, James G.
The past few years have witnessed many promising advances in HIV prevention strategies involving pre-exposure prophylaxis approaches. Some may now wonder whether an HIV vaccine is still needed, and whether developing one is even possible. The partial efficacy reported in the RV144 trial and the encouraging results of the accompanying immune correlates analysis suggest that an effective HIV vaccine is achievable. These successes have provided a large impetus and guidance for conducting more HIV vaccine trials. A key lesson learned from RV144 is that assessment of HIV acquisition is now a feasible and valuable primary objective for HIV preventive vaccine trials. In this article we review how RV144 and other HIV vaccine efficacy trials have instructed the field and highlight some of the HIV vaccine concepts in clinical development. After a long and significant investment, HIV vaccine clinical research is paying off in the form of valuable lessons that, if applied effectively, will accelerate the path toward a safe and effective vaccine. Together with other HIV prevention approaches, preventive and therapeutic HIV vaccines will be invaluable tools in bringing the epidemic to an end. PMID:24033299
Gasper, Melanie A.; Hesseling, Anneke C.; Mohar, Isaac; Myer, Landon; Azenkot, Tali; Passmore, Jo-Ann S.; Hanekom, Willem; Cotton, Mark F.; Crispe, I. Nicholas; Sodora, Donald L.; Jaspan, Heather B.
BACKGROUND. Bacillus Calmette-Guérin (BCG) vaccine is administered at birth to protect infants against tuberculosis throughout Africa, where most perinatal HIV-1 transmission occurs. We examined whether BCG vaccination alters the levels of activated HIV target T cells in HIV-exposed South African infants. METHODS. HIV-exposed infants were randomized to receive routine (at birth) or delayed (at 8 weeks) BCG vaccination. Activated and CCR5-expressing peripheral blood CD4+ T cell, monocyte, and NK cell frequencies were evaluated by flow cytometry and immune gene expression via PCR using Biomark (Fluidigm). RESULTS. Of 149 infants randomized, 92% (n = 137) were retained at 6 weeks: 71 in the routine BCG arm and 66 in the delayed arm. Routine BCG vaccination led to a 3-fold increase in systemic activation of HIV target CD4+CCR5+ T cells (HLA-DR+CD38+) at 6 weeks (0.25% at birth versus 0.08% in delayed vaccination groups; P = 0.029), which persisted until 8 weeks of age when the delayed arm was vaccinated. Vaccination of the infants in the delayed arm at 8 weeks resulted in a similar increase in activated CD4+CCR5+ T cells. The increase in activated T cells was associated with increased levels of MHC class II transactivator (CIITA), IL12RB1, and IFN-α1 transcripts within peripheral blood mononuclear cells but minimal changes in innate cells. CONCLUSION. BCG vaccination induces immune changes in HIV-exposed infants, including an increase in the proportion of activated CCR5+CD4+ HIV target cells. These findings provide insight into optimal BCG vaccine timing to minimize the risks of HIV transmissions to exposed infants while preserving potential benefits conferred by BCG vaccination. TRIAL REGISTRATION. ClinicalTrials.gov NCT02062580. FUNDING. This trial was sponsored by the Elizabeth Glaser Pediatric AIDS Foundation (MV-00-9-900-01871-0-00) and the Thrasher Foundation (NR-0095); for details, see Acknowledgments.
Ross, Anna Laura; Bråve, Andreas; Scarlatti, Gabriella; Manrique, Amapola; Buonaguro, Luigi
The search for an HIV/AIDS vaccine is steadily moving ahead, generating and validating new concepts in terms of novel vectors for antigen delivery and presentation, new vaccine and adjuvant strategies, alternative approaches to design HIV-1 antigens for eliciting protective cross-neutralising antibodies, and identification of key mechanisms in HIV infection and modulation of the immune system. All these different perspectives are contributing to the unprecedented challenge of developing a protective HIV-1 vaccine. The high scientific value of this massive effort is its great impact on vaccinology as a whole, providing invaluable scientific information for the current and future development of new preventive vaccine as well as therapeutic knowledge-based infectious-disease and cancer vaccines.
Schiller, John T.; Castellsagué, Xavier; Garland, Suzanne M.
End of study analyses of the phase III trials of prophylactic human papillomavirus (HPV) virus-like particle (VLP) vaccines in young women are now largely completed. Two distinct vaccines were evaluated, Gardasil® (Merck & Co., Whitehouse Station, NJ USA) a quadrivalent vaccine containing VLPs of types 6, 11, 16 and 18 and Cervarix® (GlaxoSmithKline Biologicals, Rixensart, Belgium), a bivalent vaccine containing VLPs of types 16 and 18. Both vaccines exhibited excellent safety and immunogenicity profiles. The vaccines also demonstrated remarkably high and similar efficacy against the vaccine-targeted types for a range of cervical endpoints from persistent infection to cervical intraepithelial neoplasia grade 3 (CIN3) in women naïve to the corresponding type at the time of vaccination. However, protection from incident infection or disease from non-vaccine types was restricted, and the vaccines had no effect on prevalent infection or disease. Gardasil® also demonstrated strong protection against genital warts and vulvar/vaginal neoplasia associated with the vaccine types. In other trials, Gardasil® protected mid-adult women from incident infection and CIN caused by the vaccine types and protected men for incident infection, genital warts and anal intraepithelial neoplasia by the vaccine types. Cervarix® protected against vaccine-targeted anal infections in women in an end of study evaluation. For practical reasons, efficacy studies have not been conducted in the primary target populations of current vaccination programs, adolescent girls and boys. However, immunogenicity bridging studies demonstrating excellent safety and strong immune responses in adolescence, coupled with the documentation of durable antibody responses and protection in young adults, leads to an optimistic projection of the effectiveness of the vaccines in adolescent vaccination programs. Taken together, the excellent clinical trial results strongly support the potential of the vaccines as
Emch, Michael; Ali, Mohammad; Root, Elisabeth D; Yunus, Mohammad
This paper develops theory and methods for vaccine trials that utilize spatial and environmental information. Satellite imagery is used to identify whether households are connected to one another via water bodies in a study area in rural Bangladesh. Then relationships between neighborhood-level cholera vaccine coverage and placebo incidence and neighborhood-level spatial variables are measured. The study hypothesis is that unvaccinated people who are environmentally connected to people who have been vaccinated will be at lower risk compared to unvaccinated people who are environmentally connected to people who have not been vaccinated. We use four datasets including: a cholera vaccine trial database, a longitudinal demographic database of the rural population from which the vaccine trial participants were selected, a household-level geographic information system (GIS) database of the same study area, and high resolution Quickbird satellite imagery. An environmental connectivity metric was constructed by integrating the satellite imagery with the vaccine and demographic databases linked with GIS. The results show that there is a relationship between neighborhood rates of cholera vaccination and placebo incidence. Thus, people are indirectly protected when more people in their environmentally connected neighborhood are vaccinated. This result is similar to our previous work that used a simpler Euclidean distance neighborhood to measure neighborhood vaccine coverage [Ali, M., Emch, M., von Seidlein, L., Yunus, M., Sack, D. A., Holmgren, J., et al. (2005). Herd immunity conferred by killed oral cholera vaccines in Bangladesh. Lancet, 366(9479), 44-49]. Our new method of measuring environmental connectivity is more precise since it takes into account the transmission mode of cholera and therefore this study validates our assertion that the oral cholera vaccine provides indirect protection in addition to direct protection.
Dhalla, Shayesta; Poole, Gary
HIV vaccine preparedness studies (VPS) are important precursors to HIV vaccine trials. As well, they contribute to an understanding of motivators and barriers for participation in hypothetical HIV vaccine trials. Motivators can take the form of altruism and a desire for social benefits. Perceived personal benefits, including psychological, personal, and financial well-being, may also motivate participation. The authors performed a systematic review of HIV VPS using the Cochrane Database for Systematic Reviews, Medline, PubMed, Embase, and Google Scholar. The authors independently searched the literature for individual HIV VPS that examined motivators of participation in a hypothetical HIV vaccine trial, using the same search strategy. As the denominators employed in the literature varied across studies, the denominators were standardized to the number of respondents per survey item, regardless of their willingness to participate (WTP) in an HIV vaccine trial. The authors retrieved eight studies on social benefits (i.e., altruism) and 11 studies on personal benefits conducted in the Organization for Economic Co-operation and Development (OECD) countries, as well as 19 studies on social benefits and 20 studies on personal benefits in the non-OECD countries. Various different forms of altruism were found to be the major motivators for participation in an HIV vaccine trial in both the OECD and the non-OECD countries. In a large number of studies, protection from HIV was cited as a personal motivator for participation in a hypothetical HIV vaccine trial in the OECD and the non-OECD countries. Knowledge of motivators can inform and target recruitment for HIV vaccine trials, although it must be remembered that hypothetical motivators may not always translate into motivators in an actual vaccine trial.
Marimuthu, Priya; Ravinder, Jamuna Rani
Dengue is one of the most important vector-borne disease and an increasing problem worldwide because of current globalization trends. Roughly, half the world's population lives in dengue endemic countries, and nearly 100 million people are infected annually with dengue. India has the highest burden of the disease with 34% of the global cases. In the context of an expanding and potentially fatal infectious disease without effective prevention or specific treatment, the public health value of a protective vaccine is clear. There is no licensed dengue vaccine is available still, but several vaccines are under development. Keeping in view the rise in dengue prevalence globally, there is a need to increase clinical drug and vaccine research on dengue. This paper briefly reviews on the development and current status of dengue vaccine to provide information to policymakers, researchers, and public health experts to design and implement appropriate vaccine for prophylactic intervention. PMID:27843790
Montali, R J; Bartz, C R; Teare, J A; Allen, J T; Appel, M J; Bush, M
Two types of killed canine distemper virus (CDV) vaccine and a modified-live CDV vaccine were clinically evaluated in four species of exotic carnivores. In 16 trials in which 13 red pandas (Ailurus fulgens) were given the killed vaccine, only 1 animal had a virus-neutralization titer that exceeded 1:100. A red panda given modified-live CDV vaccine deemed safe for gray foxes and ferrets died of bacterial pneumonia 16 days later. There was no pathologic evidence of canine distemper in that panda. The same modified-live vaccine proved to be immunogenic and safe in 12 bush dogs (Speothos venaticus), 5 maned wolves (Chrysocyon brachyurus), and 3 fennec foxes (Fennecus zerda) in which virus-neutralization titers often exceeded 1:512 and persisted for several months after vaccination.
Sheppard, Haynes W
Inactivated or "killed" virus (KV) is a "classical" approach that has produced safe and effective human and veterinary vaccines but has received relatively little attention in the effort to develop an HIV/AIDS vaccine. Initially, KV and rgp120 subunit vaccines were the two most obvious approaches but, unfortunately, rgp120 has not been efficacious and the KV approach has been limited by a variety of scientific, technical, and sociological factors. For example, when responses to cellular antigens, present on SIV grown in human cells, proved to be largely responsible for efficacy, the KV approach was widely discounted. Similarly, when lab-adapted HIV-1 appeared to lose envelope glycoprotein during preparation (not the case for primary isolates), this was viewed as a fundamental barrier to the KV concept. Also, a preference for "safer", genetically-engineered vaccines, and emphasis on cellular immunity, have left KV low on the priority list for funding agencies and investigators. The recent suggestion that "native" trimeric gp120 displays conserved conformational neutralization epitopes, along with the failure of rgp120, and difficulties in raising strong cellular responses with DNA or vectored vaccines, has restored some interest in the KV concept. In the past 15 years, several groups have initiated pre-clinical development of KV candidates for SIV or HIV and promising, albeit limited, information has been produced. In this chapter we discuss the rationale (including pros and cons) for producing and testing killed-HIV vaccines, the prospects for success, the nature and scope of research needed to test the KV concept, what has been learned to date, and what remains undone.
Mackiewicz, Jacek; Mackiewicz, Andrzej
Advances in molecular and cellular biology as well as biotechnology led to definition of a group of drugs referred to as medicinal products of advanced technologies. It includes gene therapy products, somatic cell therapeutics and tissue engineering. Therapeutic cancer vaccines including whole cell tumor cells vaccines or gene modified whole cells belong to somatic therapeutics and/or gene therapy products category. The drug development is a multistep complex process. It comprises of two phases: preclinical and clinical. Guidelines on preclinical testing of cell based immunotherapy medicinal products have been defined by regulatory agencies and are available. However, clinical testing of therapeutic cancer vaccines is still under debate. It presents a serious problem since recently clinical efficacy of the number of cancer vaccines has been demonstrated that focused a lot of public attention. In general clinical testing in the current form is very expensive, time consuming and poorly designed what may lead to overlooking of products clinically beneficial for patients. Accordingly regulatory authorities and researches including Cancer Vaccine Clinical Trial Working Group proposed three regulatory solutions to facilitate clinical development of cancer vaccines: cost-recovery program, conditional marketing authorization, and a new development paradigm. Paradigm includes a model in which cancer vaccines are investigated in two types of clinical trials: proof-of-principle and efficacy. The proof-of-principle trial objectives are: safety; dose selection and schedule of vaccination; and demonstration of proof-of-principle. Efficacy trials are randomized clinical trials with objectives of demonstrating clinical benefit either directly or through a surrogate. The clinical end points are still under debate.
Walsh, Peter D.; Kurup, Drishya; Hasselschwert, Dana L.; Wirblich, Christoph; Goetzmann, Jason E.; Schnell, Matthias J.
Could new oral vaccine technologies protect endangered wildlife against a rising tide of infectious disease? We used captive chimpanzees to test oral delivery of a rabies virus (RABV) vectored vaccine against Ebola virus (EBOV), a major threat to wild chimpanzees and gorillas. EBOV GP and RABV GP-specific antibody titers increased exponentially during the trial, with rates of increase for six orally vaccinated chimpanzees very similar to four intramuscularly vaccinated controls. Chimpanzee sera also showed robust neutralizing activity against RABV and pseudo-typed EBOV. Vaccination did not induce serious health complications. Blood chemistry, hematologic, and body mass correlates of psychological stress suggested that, although sedation induced acute stress, experimental housing conditions did not induce traumatic levels of chronic stress. Acute behavioral and physiological responses to sedation were strongly correlated with immune responses to vaccination. These results suggest that oral vaccination holds great promise as a tool for the conservation of apes and other endangered tropical wildlife. They also imply that vaccine and drug trials on other captive species need to better account for the effects of stress on immune response. PMID:28277549
Mehta, Shantanu; Goyal, Vishal; Singh, Kavita
An appropriately equipped and staffed Phase I unit is critical for smooth conduct of a first-in-man clinical trial. The first-in-man prophylactic vaccine trial(s) requires basic infrastructure of clinical trial site, experienced and dedicated site staff and healthy adults as volunteers. The facility should have access to equipment, emergency services, laboratory, pharmacy and archiving. In terms of design, infrastructure, workflow and manpower, a Phase I unit for testing a novel vaccine or drug are quite similar. However, there are some important attributes, which should be taken into consideration, while performing pre-trial site selection for conducting phase I trial with a new or novel vaccine. PMID:25878951
Stringer, L A; Wilson, P R; Heuer, C; Mackintosh, C G
A randomised controlled trial to assess the efficacy of Silirum vaccine in control of paratuberculosis in young farmed deer was carried out in 2008-2009 in six New Zealand herds with a history of clinical disease. Vaccination with Silirum was carried out in four-month-old deer, and vaccinates (n=1671) and controls (n=1664) were weighed at vaccination and at 8 and 12 months old, when faecal samples were collected from 125 vaccinates and 123 controls on five farms. Deer were slaughtered between 11 and 20 months of age, and the incidence of gross visceral lymph node (VLN) pathology typical of paratuberculosis in deer, that is, enlarged and/or granulomatous VLN, was recorded. Clinical disease was confirmed in 18 controls and seven vaccinates, representing a vaccine efficacy estimate of 60 per cent (95% CI 3 per cent to 83 per cent, P=0.04). Forty-seven percent (95% CI 38 per cent to 56 per cent) of faecal samples from vaccinates and 55 per cent (95% CI 46 per cent to 64 per cent) from controls were Mycobacterium avium subspecies paratuberculosis positive (P=0.5). Average daily liveweight gain did not differ between the cohorts. At slaughter, 1.4 per cent of vaccinates and 4.5 per cent of controls had VLN pathology, RR=0.32 (95% CI 0.19 to 0.54, P<0.001). These data indicate that vaccination with Silirum may be useful as an aid to control losses associated with clinical paratuberculosis in young deer.
A World Health Organization expert meeting on Ebola vaccines proposed urgent safety and efficacy studies in response to the outbreak in West Africa. One approach to communicable disease control is ring vaccination of individuals at high risk of infection due to their social or geographical connection to a known case. This paper describes the protocol for a novel cluster randomised controlled trial design which uses ring vaccination.In the Ebola ça suffit ring vaccination trial, rings are randomised 1:1 to (a) immediate vaccination of eligible adults with single dose vaccination or (b) vaccination delayed by 21 days. Vaccine efficacy against disease is assessed in participants over equivalent periods from the day of randomisation. Secondary objectives include vaccine effectiveness at the level of the ring, and incidence of serious adverse events. Ring vaccination trials are adaptive, can be run until disease elimination, allow interim analysis, and can go dormant during inter-epidemic periods.
... Animal and Plant Health Inspection Service Oral Rabies Vaccine Trial; Availability of a Risk Assessment... prepared to assess the risks associated with an experimental rabies vaccine, analyzes the use of that vaccine in field safety and efficacy trials in West Virginia. The proposed field trial is necessary...
Pol, Jonathan; Bloy, Norma; Buqué, Aitziber; Eggermont, Alexander; Cremer, Isabelle; Sautès-Fridman, Catherine; Galon, Jérôme; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo
Malignant cells express antigens that can be harnessed to elicit anticancer immune responses. One approach to achieve such goal consists in the administration of tumor-associated antigens (TAAs) or peptides thereof as recombinant proteins in the presence of adequate adjuvants. Throughout the past decade, peptide vaccines have been shown to mediate antineoplastic effects in various murine tumor models, especially when administered in the context of potent immunostimulatory regimens. In spite of multiple limitations, first of all the fact that anticancer vaccines are often employed as therapeutic (rather than prophylactic) agents, this immunotherapeutic paradigm has been intensively investigated in clinical scenarios, with promising results. Currently, both experimentalists and clinicians are focusing their efforts on the identification of so-called tumor rejection antigens, i.e., TAAs that can elicit an immune response leading to disease eradication, as well as to combinatorial immunostimulatory interventions with superior adjuvant activity in patients. Here, we summarize the latest advances in the development of peptide vaccines for cancer therapy. PMID:26137405
Andrasik, Michele; Karuna, Shelly T.; Broder, Gail B.; Collins, Clare; Liu, Albert; Lucas, Jonathan Paul; Harper, Gary W.; Renzullo, Philip O.
Abstract: In 2009, the National Institutes of Health recognized the need to expand knowledge of lesbian, gay, bisexual, and transgender (LGBT) health and commissioned the Institute of Medicine to report on the health of these populations in the United States. The resulting Institute of Medicine publication called for more knowledge of the health of LGBT populations, as well as improved methodologies to reach them, more LGBT-focused research, and enhanced training programs and cultural competency of physicians and researchers. Several of the National Institutes of Health–funded HIV/AIDS clinical trials networks, including the Adolescent Medicine Trials Network for HIV/AIDS Interventions, HIV Prevention Trials Network, HIV Vaccine Trials Network, and Microbicide Trials Network, have focused attention on engaging transgender (TG) individuals in research. They have identified issues that transcend the nature of research (ie, treatment or prevention, adult or adolescent) and have adopted various approaches to effectively engage the TG community. Each network has recognized the importance of developing partnerships to build trust with and seek input from TG individuals on research plans and policies. They have established standing advisory groups and convened consultations for this purpose. To ensure that trial data are reflective of the participants they are seeking to enroll, they have reviewed and revised data collection forms to incorporate the 2-step method of collecting sex at birth and gender identity as 2 independent variables, and some have also revised research protocol templates and policies for concept development to ensure that they are appropriate for the inclusion of TG participants. The networks have also initiated trainings to enhance cultural sensitivity and developed a range of materials and resources for network and clinical research site staff. They continue to identify TG-specific research needs in an effort to be more responsive to and improve
A meeting was organized by the Joint United Nations Programme on HIV/AIDS (UNAIDS), the World Health Organisation (WHO) and the Japanese National Institute of Infectious Diseases (NIID) with the following objectives: (i) to discuss public health and economic rationale to accelerate the development and evaluation of HIV vaccines suitable for use in Asia; (ii) to review ongoing preclinical HIV vaccine research in Asia; (iii) to review the Asian experience in conducting clinical trials of HIV candidate vaccines; (iv) to explore possibilities for international collaboration between countries in the region and with other countries and institutions; and (v) to discuss issues related to availability of future effective HIV vaccines. The meeting was attended by participants from Australia, China, France, Germany, India, Japan, Malaysia, Myanmar, South Korea, Thailand, United Kingdom, and the United States of America. The HIV epidemic in Asia is rapidly spreading and has already resulted in a total of 7 million HIV infections in the region. The epidemic already has a significant public health and economic impact, which may be worse in the future, unless effective intervention programmes are successfully implemented. A safe, effective, and affordable vaccine should be considered as the best hope for a long-term solution to the HIV epidemic in Asia. Asian scientists and institutions have established a number of international collaborations to isolate and characterize prevalent HIV-1 strains (mostly belonging to subtypes C and E) and are developing candidate vaccines based on these subtypes. In the region, phase I/II clinical trials of preventative HIV candidate vaccines have been conducted in Australia, China and Thailand. Since 1993, a comprehensive National AIDS Vaccine Plan has allowed Thailand to conduct phase I/II trials of six different preventative or therapeutic candidate vaccines, and the first phase III preventative efficacy trial has been approved. The meeting
Live oral candidate rotavirus vaccines of bovine (RIT 4237) or rhesus (RRV-1) origin and reassortants of RRV-1 expressing human serotype 1 (DxRRV) or serotype 2 (DS1xRRV) VP7 protein were evaluated for clinical efficacy in young children in successive trials from 1983 to 1989. In each study, the vaccinations were given before a rotavirus epidemic season and the follow-up of vaccinees covered two rotavirus epidemic seasons lasting up to 2-3 years of age. Serotype 1 rotavirus was predominant in each season. Protection rates against all rotavirus-associated diarrhoea ranged from 0 to 67% but were higher, up to 100%, against more severe rotavirus disease. All tested vaccines also showed efficacy for diarrhoea not apparently associated with rotavirus; therefore the clinical benefit of the vaccinations was greater than could be deduced from efficacy rates for rotavirus-associated diarrhoea alone. Each of the candidate vaccines could significantly reduce severe diarrhoea in Finnish children in the first 2 to 3 years of life. For optimal efficacy, the vaccines should be administered in the autumn before the regular epidemic season of rotavirus.
Pérez-Guerra, Carmen L; Rodríguez-Acosta, Rosa L; Soto-Gómez, Eunice; Zielinski-Gutierrez, Emily; Peña-Orellana, Marisol; Santiago, Luis M; Rivera, Reinaldo; Cruz, R Rhode; Ramírez, Viani; Tomashek, Kay M; Dayan, Gustavo
Dengue, endemic in Puerto Rico, is a major public health problem. Vaccines are thought the best means to prevent dengue because vector control alone has been largely ineffective. We implemented qualitative studies in 2006 and 2010 to determine the acceptability of conducting placebo-controlled dengue vaccine efficacy trials in Puerto Rican children. Key informant interviews and focus groups with parents and children were conducted in municipalities with high dengue incidence. We used structured open-ended questions to determine motivators and attitudes regarding vaccine trial participation. Knowledge about dengue risk and prevention, and knowledge, attitudes, and beliefs regarding vaccines and vaccine trials were assessed. Using grounded theory, we conducted content analysis and established categories and sub-categories of participant responses. All participants were knowledgeable about dengue prevention and perceived children as most affected age groups. Participants were aware of vaccines benefits and they thought a vaccine could prevent dengue. However, most would not allow their children to participate in a placebo-controlled vaccine trial. Barriers included lack of trust in new vaccines and vaccine trial procedures; fear of developing dengue or side effects from the vaccine and lack of information about candidate dengue vaccines. Participants thought information, including results of previous trials might overcome barriers to participation. Motivators for participation were altruism, protection from dengue, free medical attention, and compensation for transportation and participation. Parents would consider children participation if accurate vaccine trial information is provided.
Bishai, David; Pariyo, George; Ainsworth, Martha; Hill, Kenneth
OBJECTIVE: To assess the factors affecting demand for an HIV/AIDS vaccine among adults in their prime earning and childbearing years and the impact of vaccination on risk behaviour in a high-prevalence, low-income country. METHODS: A contingent valuation survey of 1677 adults aged 18-60 years was conducted in 12 districts in Uganda. Respondents were asked about a hypothetical vaccine to prevent HIV infection. Households were randomly assigned survey questionnaires with one of two levels of vaccine efficacy (50% or 95%) and one of five prices. The influence of demographic characteristics, vaccine efficacy, self-assessed risk of infection, price, and household assets on vaccine demand was assessed using multivariate regression analysis. FINDINGS: Altogether, 94% (1576/1677) of respondents would be willing to be vaccinated with a free HIV/AIDS vaccine; 31% (78/251) would not be willing to be vaccinated at a price of 5000 Ugandan shillings (2.86 U.S. dollars). Household wealth, vaccine price, and risk behaviour were significant determinants of individual demand. Demand was equally high for both low-efficacy and high-efficacy vaccines. Respondents believed that condom use would be slightly less necessary with a high-efficacy vaccine (655/825; 79.4%) than a low-efficacy vaccine (690/843; 81.8%). However, reported condom use with partners other than spouses in the absence of a vaccine was much lower (137/271; 50.6%), with 26% (175/670) of men and 9.5% (96/1007) of women reporting having had partners other than their spouses during the past year. CONCLUSION: The high demand for an AIDS vaccine of any level of efficacy can be explained by the heavy toll of AIDS in Uganda: 72% (990/1371) of respondents had lost a family member to the disease. An AIDS vaccine would be self-targeting: those with a greater chance of becoming infected and spreading HIV would be more likely to seek a vaccine, improving the efficiency of vaccination programmes. However,,high levels of risk
... Animal and Plant Health Inspection Service Oral Rabies Vaccine Trial; Availability of an Environmental... experimental rabies vaccine in field safety and immunogenicity trials in portions of New Hampshire, New York... vaccine that will produce sufficient levels of population immunity in raccoons and striped skunks. We...
... and Plant Health Inspection Service [Docket No. APHIS-2013-0046] Oral Rabies Vaccine Trial... vaccine for wildlife to additional areas in New York. The proposed field trial is necessary to evaluate whether the wildlife rabies vaccine will produce sufficient levels of population immunity against...
... Animal and Plant Health Inspection Service Oral Rabies Vaccine Trial; Availability of an Environmental... with the proposed field trial to test the safety and efficacy of an experimental oral rabies vaccine....3 wildlife rabies vaccine in New Hampshire, New York, Ohio, Vermont, and West Virginia,...
Belshe, Robert B.; Leone, Peter A.; Bernstein, David I.; Wald, Anna; Levin, Myron J.; Stapleton, Jack T.; Gorfinkel, Iris; Morrow, Rhoda L. Ashley; Ewell, Marian G.; Stokes-Riner, Abbie; Dubin, Gary; Heineman, Thomas C.; Schulte, Joann M.; Deal, Carolyn D.
Background Two previous studies of a herpes simplex virus type 2 (HSV-2) subunit vaccine containing glycoprotein D in HSV-discordant couples revealed 73% and 74% efficacy against genital disease in women who were negative for both HSV type 1 (HSV-1) and HSV-2 antibodies. Efficacy was not observed in men or HSV-1 seropositive women. Methods We conducted a randomized, double-blind efficacy field trial involving 8323 women 18 to 30 years of age who were negative for antibodies to HSV-1 and HSV-2. At months 0, 1, and 6, some subjects received the investigational vaccine, consisting of 20 μg of glycoprotein D from HSV-2 with alum and 3-O-deacylated monophosphoryl lipid A as an adjuvant; control subjects received the hepatitis A vaccine, at a dose of 720 enzyme-linked immunosorbent assay (ELISA) units. The primary end point was occurrence of genital herpes disease due to either HSV-1 or HSV-2 from month 2 (1 month after dose 2) through month 20. Results The HSV vaccine was associated with an increased risk of local reactions as compared with the control vaccine, and it elicited ELISA and neutralizing antibodies to HSV-2. Overall, the vaccine was not efficacious; vaccine efficacy was 20% (95% confidence interval [CI], −29 to 50) against genital herpes disease. However, efficacy against HSV-1 genital disease was 58% (95% CI, 12 to 80). Vaccine efficacy against HSV-1 infection (with or without disease) was 35% (95% CI, 13 to 52), but efficacy against HSV-2 infection was not observed (−8%; 95% CI, −59 to 26). Conclusions In a study population that was representative of the general population of HSV-1– and HSV-2–seronegative women, the investigational vaccine was effective in preventing HSV-1 genital disease and infection but not in preventing HSV-2 disease or infection. (Funded by the National Institute of Allergy and Infectious Diseases and GlaxoSmithKline; ClinicalTrials.gov number, NCT00057330.) PMID:22216840
Iseki, M; Broderson, J R; Pirl, K G; Igarashi, I; Collins, W E; Aikawa, M
Renal specimens of 16 owl monkeys (Aotus vociferans) were studied by light microscopy and immunohistochemistry during a vaccine trial with recombinant proteins of the ring-infected erythrocyte surface antigen (RESA) of Plasmodium falciparum. Deposition of IgG, C3, and P. falciparum antigens in the mesangium was demonstrated by the peroxidase anti-peroxidase (PAP) method. A relationship between the severity of parasitemia at the time of death and the presence of nephropathy was not apparent.
Voytek, Chelsea D; Jones, Kevin T; Metzger, David S
Efficacy studies of investigational HIV vaccines require enrollment of individuals at 'high risk' for HIV. This paper examines participation in HIV vaccine trials among women at 'high risk' for HIV acquisition. In-depth interviews were conducted with 17 African-American women who use crack cocaine and/or exchange sex for money/drugs to elicit attitudes toward medical research and motivators and deterrents to HIV vaccine trial participation. Interviews were digitally recorded and transcribed; data were coded and compiled into themes. Most women expressed favorable attitudes toward medical research in general. Motivators for trial participation included compensation; personal benefits including information, social services, and the possibility that the trial vaccine could prevent HIV; and altruism. Deterrents included: dislike of needles; distrust; concern about future consequences of participating. In addition, contingencies, care-giving responsibilities, and convenience issues constituted barriers which could impede participation. Respondents described varied, complex perspectives, and individual cases illustrate how these themes played out as women contemplated trial participation. Understanding factors which influence vaccine research participation among women at 'high risk' can aid sites to tailor recruitment procedures to local contexts. Concerns about future reactions can be addressed through sustained community education. Convenience barriers can be ameliorated by providing rides to study visits when necessary, and/or conducting study visits in accessible neighborhood locations. Women in this sample thought carefully about enrolling in HIV vaccine trials given the structural constraints within which they lived. Further research is needed regarding structural factors which influence personal agency and individuals' thinking about research participation.
By Frank Blanchard, Staff Writer, and Jeff Lifson, Guest Writer Scientists at the Oregon Health & Science University and the AIDS and Cancer Virus Program of the Frederick National Laboratory for Cancer Research have used a novel vaccine approach to achieve a “functional cure” and apparent eradication of infection with a monkey version of the AIDS virus.
Immunization is one of the most beneficial and cost-effective disease prevention measures. There are global efforts to develop new vaccines for disease control. The vaccine clinical trials must be conducted in the countries where they will be used. This has led to vaccine trials being conducted across Asia and Africa where there is a high burden of infectious diseases. The setup and successful conduct of International standard GCP vaccine trials across trial centers located in resource constrained settings are challenging. The challenges, ethical considerations and impact of the implementation of clinical trials in low-resource settings are highlighted here to help vaccine development programs successfully conduct such trials.
Butterfield, Lisa H
A wide variety of tumor antigens have been targeted in cancer immunotherapy studies. Traditionally, the focus has been on commonly overexpressed antigens shared across many patients and/or tumor types. As the field has progressed, the identity of human tumor rejection antigens has broadened. Immunologic monitoring of clinical trials has slowly elucidated candidate biomarkers of immune response and clinical response, and conversely, of immune dysfunction and suppression. We have utilized MART-1/Melan-A in our melanoma studies and observed a high frequency of immune responses and several significant clinical responses in patients vaccinated with this melanosomal protein. Alpha-fetoprotein is a shared, overexpressed tumor antigen and secreted glycoprotein that we have tested in hepatocellular cancer vaccines. Our recent studies have identified immunosuppressive and immune-skewing activities of this antigen. The choice of target antigen and its form can have unexpected effects.
Webster, Diane E; Thomas, Merlin C; Pickering, Raelene; Whyte, Andrew; Dry, Ian B; Gorry, Paul R; Wesselingh, Steve L
Although educational programs have had some impact, immunization against HIV will be necessary to control the AIDS pandemic. To be effective, vaccination will need to be accessible and affordable, directed against multiple antigens, and delivered in multiple doses. Plant-based vaccines that are heat-stable and easy to produce and administer are suited to this type of strategy. Pilot studies by a number of groups have demonstrated that plant viral expression systems can produce HIV antigens in quantities that are appropriate for use in vaccines. In addition, these plant-made HIV antigens have been shown to be immunogenic. However, given the need for potent cross-clade humoral and T-cell immunity for protection against HIV, and the uncertainty surrounding the efficacy of protein subunit vaccines, it is most likely that plant-made HIV vaccines will find their niche as booster immunizations in prime-boost vaccination schedules.
... HUMAN SERVICES Food and Drug Administration Cooperative Agreement To Support Innovation in Vaccine... Vaccines AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug... innovative approaches to vaccine clinical trial design and to enhance the utilization of a range...
Combe, Pierre; de Guillebon, Eleonore; Thibault, Constance; Granier, Clémence; Tartour, Eric; Oudard, Stéphane
Despite the renaissance of cancer immunotherapy, no novel immunotherapy has been approved for the treatment of renal cell cancer (RCC) since the availability of recombinant cytokines (interleukin-2, interferon-α). All vaccine trials have failed to meet their endpoints although they have highlighted potential predictive biomarkers (e.g., pre-existing immune response, hematological parameters, tumor burden). Recent advances in immunomodulatory therapies have prompted the study of combination treatments targeting the tumor immunosuppressive microenvironment consisting of regulatory T-cells (Treg), myeloid suppressor cells, and cytokines. Approaches under investigation are use of inhibitors to curb the overexpression of immune checkpoint ligands by tumor cells (e.g., anti-CTLA-4, anti-PD-1/PD-L1) and exploiting the immunomodulatory effects of anti-angiogenic agents that are the current standard of metastatic RCC care. Phase III trials are focusing on the possible synergy between therapeutic vaccines (e.g., IMA-901 and AGS-003) and anti-angiogenic agents.
Kitchen, A D; Hewitt, P E
We report two instances of human immunodeficiency virus (HIV) serological screening reactivity in blood donations which were subsequently determined to be due to donor participation in HIV vaccine trials. Both donations were screen reactive with atypical patterns on confirmation; no definitive conclusion could be given for either donor. Subsequent questioning identified that both donors had been involved in HIV vaccine trials. In both cases the screening and confirmation identified the presence of HIV antibodies, although vaccine induced. While clinical trials of vaccines are important, the implications of some need careful consideration if they are not to adversely impact other areas of healthcare.
... Animal and Plant Health Inspection Service Oral Rabies Vaccine Trial; Availability of an Environmental... rabies vaccination field trial in West Virginia. Based on its finding of no significant impact, the... be prepared. FOR FURTHER INFORMATION CONTACT: Dr. Dennis Slate, Rabies Program Coordinator,...
... Animal and Plant Health Inspection Service Oral Rabies Vaccine Trial; Availability of a Supplement to an... relative to an oral rabies vaccination field trial in New Hampshire, New York, Ohio, Vermont, ] and West.... Richard Chipman, Rabies Program Coordinator, Wildlife Services, APHIS, 59 Chennell Drive, Suite 7,...
Mayer, Kenneth H.; Elizaga, Marnie L.; Bekker, Linda-Gail; Allen, Mary; Morris, Lynn; Montefiori, David; De Rosa, Stephen C.; Sato, Alicia; Gu, Niya; Tomaras, Georgia D.; Tucker, Timothy; Barnett, Susan W.; Mkhize, Nonhlanhla N.; Shen, Xiaoying; Downing, Katrina; Williamson, Carolyn; Pensiero, Michael; Corey, Lawrence; Williamson, Anna-Lise
A phase I safety and immunogenicity study investigated South African AIDS Vaccine Initiative (SAAVI) HIV-1 subtype C (HIV-1C) DNA vaccine encoding Gag-RT-Tat-Nef and gp150, boosted with modified vaccinia Ankara (MVA) expressing matched antigens. Following the finding of partial protective efficacy in the RV144 HIV vaccine efficacy trial, a protein boost with HIV-1 subtype C V2-deleted gp140 with MF59 was added to the regimen. A total of 48 participants (12 U.S. participants and 36 Republic of South Africa [RSA] participants) were randomized to receive 3 intramuscular (i.m.) doses of SAAVI DNA-C2 of 4 mg (months 0, 1, and 2) and 2 i.m. doses of SAAVI MVA-C of 1.45 × 109 PFU (months 4 and 5) (n = 40) or of a placebo (n = 8). Approximately 2 years after vaccination, 27 participants were rerandomized to receive gp140/MF59 at 100 μg or placebo, as 2 i.m. injections, 3 months apart. The vaccine regimen was safe and well tolerated. After the DNA-MVA regimen, CD4+ T-cell and CD8+ T-cell responses occurred in 74% and 32% of the participants, respectively. The protein boost increased CD4+ T-cell responses to 87% of the subjects. All participants developed tier 1 HIV-1C neutralizing antibody responses as well as durable Env binding antibodies that recognized linear V3 and C5 peptides. The HIV-1 subtype C DNA-MVA vaccine regimen showed promising cellular immunogenicity. Boosting with gp140/MF59 enhanced levels of binding and neutralizing antibodies as well as CD4+ T-cell responses to HIV-1 envelope. (This study has been registered at ClinicalTrials.gov under registration no. NCT00574600 and NCT01423825.) PMID:27098021
Gray, Glenda E; Mayer, Kenneth H; Elizaga, Marnie L; Bekker, Linda-Gail; Allen, Mary; Morris, Lynn; Montefiori, David; De Rosa, Stephen C; Sato, Alicia; Gu, Niya; Tomaras, Georgia D; Tucker, Timothy; Barnett, Susan W; Mkhize, Nonhlanhla N; Shen, Xiaoying; Downing, Katrina; Williamson, Carolyn; Pensiero, Michael; Corey, Lawrence; Williamson, Anna-Lise
A phase I safety and immunogenicity study investigated South African AIDS Vaccine Initiative (SAAVI) HIV-1 subtype C (HIV-1C) DNA vaccine encoding Gag-RT-Tat-Nef and gp150, boosted with modified vaccinia Ankara (MVA) expressing matched antigens. Following the finding of partial protective efficacy in the RV144 HIV vaccine efficacy trial, a protein boost with HIV-1 subtype C V2-deleted gp140 with MF59 was added to the regimen. A total of 48 participants (12 U.S. participants and 36 Republic of South Africa [RSA] participants) were randomized to receive 3 intramuscular (i.m.) doses of SAAVI DNA-C2 of 4 mg (months 0, 1, and 2) and 2 i.m. doses of SAAVI MVA-C of 1.45 × 10(9) PFU (months 4 and 5) (n = 40) or of a placebo (n = 8). Approximately 2 years after vaccination, 27 participants were rerandomized to receive gp140/MF59 at 100 μg or placebo, as 2 i.m. injections, 3 months apart. The vaccine regimen was safe and well tolerated. After the DNA-MVA regimen, CD4(+) T-cell and CD8(+) T-cell responses occurred in 74% and 32% of the participants, respectively. The protein boost increased CD4(+) T-cell responses to 87% of the subjects. All participants developed tier 1 HIV-1C neutralizing antibody responses as well as durable Env binding antibodies that recognized linear V3 and C5 peptides. The HIV-1 subtype C DNA-MVA vaccine regimen showed promising cellular immunogenicity. Boosting with gp140/MF59 enhanced levels of binding and neutralizing antibodies as well as CD4(+) T-cell responses to HIV-1 envelope. (This study has been registered at ClinicalTrials.gov under registration no. NCT00574600 and NCT01423825.).
Novitsky, V; Smith, U R; Gilbert, P; McLane, M F; Chigwedere, P; Williamson, C; Ndung'u, T; Klein, I; Chang, S Y; Peter, T; Thior, I; Foley, B T; Gaolekwe, S; Rybak, N; Gaseitsiwe, S; Vannberg, F; Marlink, R; Lee, T H; Essex, M
approach could overcome the high genetic diversity of HIV-1C and facilitate an AIDS vaccine design, particularly if the assumption that an HIV-1C antigen with a more extensive match to the circulating viruses is likely to be more efficacious is proven in efficacy trials.
Starace, Fabrizio; Embrione, Francesco; Fusco, Maria Luigia; Cafaro, Loredana
The production of an effective vaccine for HIV infection is one of the major challenges for the third millennium public health. Here we review published studies addressing the issue of incentives and barriers influencing the choice to participate in a vaccine trial. Currently available literature clearly indicates the need to include psychosocial dimensions in the preparation and implementation of vaccine trials. The underestimation of participants' satisfaction about information communication may lead to non-adherence and to drop-out from the trials. Proper attention to communication skills of professionals involved in participants' enrollment and follow-up is essential to ensure trial success.
Hayami, Masanori; Horiuchi, Reii
A great effort for developing AIDS vaccine has been carried out in the world, designed by various new ideas based on basic research information obtained in recent virology and immunology. Withall it, to obtain effective AIDS vaccine is considered skeptical. One of the reasons of its difficulty is a lack of experimental animals susceptible to HIV-1. In our laboratory, we have succeeded in developing chimeric SIV having 3' half of HIV-1 genome including env (SHIV), which is infectious to macaque monkeys. One of SHIVs has been proved nonpathogenic in monkeys from various aspects and it afforded protective immunity to monkeys against pathogenic SHIV challenge infection. Now, we are trying to develop anti-HIV live attenuated vaccines using the nonpathogenic SHIV as a starting material. In the history of virus vaccine, live attenuated vaccines have been proved most effective in measles and polio-myelitis. However, it is not clear whether nonpathogenic HIV exists or not. Futhermore, even if nonpathogenic HIV could be obtained, there is possibility that it will easily mutate to pathogenic one. Therefore, to develop live attenuated AIDS vaccine is considered dangerous. In this article, We will introduce our research on SHIV pathogenicity using monkeys and hypothesize possibility to obtain nonpathogenic HIV which is speculated from the origin and evolution of HIV/SIV. To clarify virulence and nonvirulence of HIV and to obtain nonpathogenic virus are not only applied research but also basic science to dissolve the fundemental question why HIV can induce the disease.
A-A191 992 MOLECULAR MECHANISMS OF CYTOPATHGNIT OFPIMT LYMPHOTROPIC RETROVI (U) BIOTECH RESEARCH LASS INC :OCKVILLEMD M M MANAK ET AL 28 OCT 87...TREATMENT AND VACCINE FOR AIDS ~Annual Report ’ JCovering the Period 9/29/86 to 9/28/87 by4 SMark M . Manak and Linda L. Jagodzinski i! October 28, 1987...Treatment and Vaccine for AIDS 12. PERSONAL AUTHOR(S) Manak, Mark M . and Linda L. Jagodzinski 13a. TYPE OF REPORT 13b. TIME COVERED 114. DATE OF REPORT
Harmon, Thomas M.; Fisher, Kevin A.; McGlynn, Margaret G.; Stover, John; Warren, Mitchell J.; Teng, Yu; Näveke, Arne
Background The Investment Framework Enhanced (IFE) proposed in 2013 by the Joint United Nations Programme on HIV/AIDS (UNAIDS) explored how maximizing existing interventions and adding emerging prevention options, including a vaccine, could further reduce new HIV infections and AIDS-related deaths in low- and middle-income countries (LMICs). This article describes additional modeling which looks more closely at the potential health impact and cost-effectiveness of AIDS vaccination in LMICs as part of UNAIDS IFE. Methods An epidemiological model was used to explore the potential impact of AIDS vaccination in LMICs in combination with other interventions through 2070. Assumptions were based on perspectives from research, vaccination and public health experts, as well as observations from other HIV/AIDS interventions and vaccination programs. Sensitivity analyses varied vaccine efficacy, duration of protection, coverage, and cost. Results If UNAIDS IFE goals were fully achieved, new annual HIV infections in LMICs would decline from 2.0 million in 2014 to 550,000 in 2070. A 70% efficacious vaccine introduced in 2027 with three doses, strong uptake and five years of protection would reduce annual new infections by 44% over the first decade, by 65% the first 25 years and by 78% to 122,000 in 2070. Vaccine impact would be much greater if the assumptions in UNAIDS IFE were not fully achieved. An AIDS vaccine would be cost-effective within a wide range of scenarios. Interpretation Even a modestly effective vaccine could contribute strongly to a sustainable response to HIV/AIDS and be cost-effective, even with optimistic assumptions about other interventions. Higher efficacy would provide even greater impact and cost-effectiveness, and would support broader access. Vaccine efficacy and cost per regimen are critical in achieving cost-effectiveness, with cost per regimen being particularly critical in low-income countries and at lower efficacy levels. PMID:26731116
Any therapeutic vaccination approach against HIV-1 must induce CTL and Th1 cells. But, therapeutic vaccination is more than that. For extensive application of a therapeutic vaccine several questions need to be solved in advance to achieve a global impact. In this commentary some of them are addressed. We analyze the epidemiology, sociology, economy and immunopathology related to the HIV/AIDS disease. Also, important technical issues and real possibilities to overcome at least some of the major limitation of the antiretroviral treatments in the pursuit of an effective vaccine are considered. From the integration of previous analyses some conclusions are drawn. Because it is just a commentary some arguments are not unveiled into their full extension. At the end, we discuss some issues in relation to the development of the vaccine candidate TERAVAC-HIV-1 as a case study.
Alio, Amina P.; Fields, Sheldon D.; Humes, Damon L.; Bunce, Catherine A.; Wallace, Stephaun E.; Lewis, Cindi; Elder, Heather; Wakefield, Steven; Keefer, Michael C.
Men who sleep with men (MSM) and transgender individuals of color, the largest demographic in the House Ball community (HBC) are amongst the group at highest risk for HIV infection in the United States. The HBC have limited access to culturally appropriate HIV education. This study aimed to develop a partnership with HBC leaders to uncover strategies for increasing HIV prevention knowledge, including participation in HIV vaccine trials. To this end a research institution-community-HBC partnership was established. In-depth qualitative and quantitative data were collected from the 14 HBC leaders in western New York, revealing that knowledge of HIV and related vaccine trials was limited. Barriers to increasing HIV knowledge included fear of peer judgment, having inaccurate information about HIV, and lack of education. Among the HBC, community partnerships will further aid in the development of future HIV prevention programs and increase individuals’ willingness to participate in future HIV vaccine trials. PMID:25642120
Torresi, J; Ebert, G; Pellegrini, M
Dengue has become a major global public health threat with almost half of the world's population living in at-risk areas. Vaccination would likely represent an effective strategy for the management of dengue disease in endemic regions, however to date there is only one licensed preventative vaccine for dengue infection. The development of a vaccine against dengue virus (DENV) has been hampered by an incomplete understanding of protective immune responses against DENV. The most clinically advanced dengue vaccine is the chimeric yellow fever-dengue vaccine (CYD) that employs the yellow fever virus 17D strain as the replication backbone (Chimerivax-DEN; CYD-TDV). This vaccine had an overall pooled protective efficacy of 65.6% but was substantially more effective against severe dengue and dengue hemorrhagic fever. Several other vaccine approaches have been developed including live attenuated chimeric dengue vaccines (DENVax and LAV Delta 30), DEN protein subunit V180 vaccine (DEN1-80E) and DENV DNA vaccines. These vaccines have been shown to be immunogenic in animals and also safe and immunogenic in humans. However, these vaccines are yet to progress to phase III trials to determine their protective efficacy against dengue. This review will summarize the details of vaccines that have progressed to clinical trials in humans.
Sanchez, Ana M; Denny, Thomas N; O'Gorman, Maurice
This Special Issue of the Journal of Immunological Methods includes 16 manuscripts describing quality assurance activities related to virologic and immunologic monitoring of six global laboratory resource programs that support international HIV/AIDS clinical trial studies: Collaboration for AIDS Vaccine Discovery (CAVD); Center for HIV/AIDS Vaccine Immunology (CHAVI); External Quality Assurance Program Oversight Laboratory (EQAPOL); HIV Vaccine Trial Network (HVTN); International AIDS Vaccine Initiative (IAVI); and Immunology Quality Assessment (IQA). The reports from these programs address the many components required to develop comprehensive quality control activities and subsequent quality assurance programs for immune monitoring in global clinical trials including: all aspects of processing, storing, and quality assessment of PBMC preparations used ubiquitously in HIV clinical trials, the development and optimization of assays for CD8 HIV responses and HIV neutralization, a comprehensive global HIV virus repository, and reports on the development and execution of novel external proficiency testing programs for immunophenotyping, intracellular cytokine staining, ELISPOT and luminex based cytokine measurements. In addition, there are articles describing the implementation of Good Clinical Laboratory Practices (GCLP) in a large quality assurance laboratory, the development of statistical methods specific for external proficiency testing assessment, a discussion on the ability to set objective thresholds for measuring rare events by flow cytometry, and finally, a manuscript which addresses a framework for the structured reporting of T cell immune function based assays. It is anticipated that this series of manuscripts covering a wide range of quality assurance activities associated with the conduct of global clinical trials will provide a resource for individuals and programs involved in improving the harmonization, standardization, accuracy, and sensitivity of
By Frank Blanchard, Staff Writer, and Jeff Lifson, Guest Writer In a research milestone reported in the June 20 issue of the journal Science, scientists have developed a minimally modified version of HIV-1, the virus that causes AIDS in infected humans, that is capable of causing progressive infection and AIDS in monkeys. The advance should help create more authentic animal models of the disease and provide a potentially invaluable approach for faster and better preclinical evaluation of new drugs and vaccines.
Tacket, C O
Vaccines consisting of transgenic plant-derived antigens offer a new strategy for development of safe, inexpensive vaccines. The vaccine antigens can be eaten with the edible part of the plant or purified from plant material. In phase 1 clinical studies of prototype potato- and corn-based vaccines, these vaccines have been safe and immunogenic without the need for a buffer or vehicle other than the plant cell. Transgenic plant technology is attractive for vaccine development because these vaccines are needle-less, stable, and easy to administer. This chapter examines some early human studies of oral transgenic plant-derived vaccines against enterotoxigenic Escherichia coli infection, norovirus, and hepatitis B.
Takeyama, Natsumi; Kiyono, Hiroshi; Yuki, Yoshikazu
It has been about 30 years since the first plant engineering technology was established. Although the concept of plant-based pharmaceuticals or vaccines motivates us to develop practicable commercial products using plant engineering, there are some difficulties in reaching the final goal: to manufacture an approved product. At present, the only plant-made vaccine approved by the United States Department of Agriculture is a Newcastle disease vaccine for poultry that is produced in suspension-cultured tobacco cells. The progress toward commercialization of plant-based vaccines takes much effort and time, but several candidate vaccines for use in humans and animals are in clinical trials. This review discusses plant engineering technologies and regulations relevant to the development of plant-based vaccines and provides an overview of human and animal vaccines currently under clinical trials. PMID:26668752
Clemens, John; Shin, Sunheang; Ali, Mohammad
Criteria for the introduction of new vaccines into routine public health practice are becoming increasingly stringent. For vaccines that are expensive and those that provide moderate protection, the ability to confer herd protection could be crucial to policy deliberations about vaccine introduction. Traditionally, herd protection has been assessed after a vaccine is introduced, delaying the availability of data on herd effects to inform decisions about vaccine introduction. New methodological developments now provide the possibility to assess herd protection before the introduction of a vaccine into public health programmes. One approach is a cluster-randomised trial, which allows assessment of herd protection in a way that minimises biases. Analysis of individually randomised trials by appropriately selected clusters created post hoc can also provide measurements of herd protection. Here we discuss the use of these designs, which can generate an improved evidence base at an early stage for making decisions about the introduction of new vaccines.
Knight-Jones, T J D; Bulut, A N; Gubbins, S; Stärk, K D C; Pfeiffer, D U; Sumption, K J; Paton, D J
Despite years of biannual mass vaccination of cattle, foot-and-mouth disease (FMD) remains uncontrolled in Anatolian Turkey. To evaluate protection after mass vaccination we measured post-vaccination antibodies in a cohort of cattle (serotypes O, A and Asia-1). To obtain results reflecting typical field protection, participants were randomly sampled from across Central and Western Turkey after routine vaccination. Giving two-doses one month apart is recommended when cattle are first vaccinated against FMD. However, due to cost and logistics, this is not routinely performed in Turkey, and elsewhere. Nested within the cohort, we conducted a randomised trial comparing post-vaccination antibodies after a single-dose versus a two-dose primary vaccination course. Four to five months after vaccination, only a third of single-vaccinated cattle had antibody levels above a threshold associated with protection. A third never reached this threshold, even at peak response one month after vaccination. It was not until animals had received three vaccine doses in their lifetime, vaccinating every six months, that most (64% to 86% depending on serotype) maintained antibody levels above this threshold. By this time cattle would be >20 months old with almost half the population below this age. Consequently, many vaccinated animals will be unprotected for much of the year. Compared to a single-dose, a primary vaccination course of two-doses greatly improved the level and duration of immunity. We concluded that the FMD vaccination programme in Anatolian Turkey did not produce the high levels of immunity required. Higher potency vaccines are now used throughout Turkey, with a two-dose primary course in certain areas. Monitoring post-vaccination serology is an important component of evaluation for FMD vaccination programmes. However, consideration must be given to which antigens are present in the test, the vaccine and the field virus. Differences between these antigens affect the
Gikonyo, Caroline; Kamuya, Dorcas; Mbete, Bibi; Njuguna, Patricia; Olotu, Ally; Bejon, Philip; Marsh, Vicki; Molyneux, Sassy
Internationally, calls for feedback of findings to be made an 'ethical imperative' or mandatory have been met with both strong support and opposition. Challenges include differences in issues by type of study and context, disentangling between aggregate and individual study results, and inadequate empirical evidence on which to draw. In this paper we present data from observations and interviews with key stakeholders involved in feeding back aggregate study findings for two Phase II malaria vaccine trials among children under the age of 5 years old on the Kenyan Coast. In our setting, feeding back of aggregate findings was an appreciated set of activities. The inclusion of individual results was important from the point of view of both participants and researchers, to reassure participants of trial safety, and to ensure that positive results were not over-interpreted and that individual level issues around blinding and control were clarified. Feedback sessions also offered an opportunity to re-evaluate and re-negotiate trial relationships and benefits, with potentially important implications for perceptions of and involvement in follow-up work for the trials and in future research. We found that feedback of findings is a complex but key step in a continuing set of social interactions between community members and research staff (particularly field staff who work at the interface with communities), and among community members themselves; a step which needs careful planning from the outset. We agree with others that individual and aggregate results need to be considered separately, and that for individual results, both the nature and value of the information, and the context, including social relationships, need to be taken into account.
Lally, Michelle; Goldsworthy, Richard; Sarr, Moussa; Kahn, Jessica; Brown, Larry; Peralta, Ligia; Zimet, Greg
Purpose Placebo and randomization are important concepts that must be understood before youth can safely participate in HIV vaccine studies or other biomedical trials for HIV prevention. These concepts are central to the phenomenon of preventive misconception which may be associated with an increase in risk behavior among study participants related to mistaken beliefs. Persuasive messaging, traditionally used in the field of marketing, could enhance educational efforts associated with randomized clinical trials. Methods Two educational brochures were designed to increase knowledge about HIV vaccine clinical trials via 1 and 2-sided persuasive messaging. Through the Adolescent Medicine Trials Network, 120 youth were enrolled, administered a mock HIV vaccine trial consent, and then randomized to receive either no supplemental information or one of the two brochures. Results The 2-sided brochure group in which common clinical trial misconceptions were acknowledgedand then refuted had significantly higher scores on knowledge of randomization and interpretation of side effects than the consent-only control group, and willingness to participate in an HIV vaccine trial was not decreased with the use of this brochure. Conclusion Two sided persuasive messaging improves understanding of the concepts of randomization and placebo among youth who would consider participating in an HIV vaccine trial. Further evaluation of this approach should be considered for at-risk youth participating in an actual trial of a biomedical intervention for HIV prevention. PMID:24613097
Based on the action plan "Ensuring a stable supply of National Immunization Program vaccines and sovereignty of biopharmaceutical products," Korea Food and Drug Administration (KFDA) has made efforts to develop vaccines in the context of self reliance and to protect public health. Along with the recognized infrastructures for clinical trials, clinical trials for vaccines have also gradually been conducted at multinational sites as well as at local sites. KFDA will support to expand six to eleven kinds of vaccines by 2017. In accordance with integrated regulatory system, KFDA has promoted clinical trials, established national lot release procedure, and strengthened good manufacturing practices inspection and post marketing surveillance. Against this backdrop, KFDA will support the vaccine development and promote excellent public health protection.
Slack, Catherine; Strode, Ann; Grant, Catherine; Milford, Cecilia
The ethical-legal framework in South Africa is in a period of transition, with a number of new developments changing the substantive principles and procedures for health research in the country. Some of the changing dynamics include both law reform and the review of ethical guidelines. This changing environment poses many complexities for researchers, research ethics committees and participating communities involved in planning, implementing and reviewing research with child participants, including HIV vaccine trials. This paper presents the major themes and outcomes of a consultative meeting convened by the HIV AIDS Vaccines Ethics Group in July 2004 for key stakeholder groups. At this forum participants discussed the complexities posed by a transitional and sometimes contradictory ethical-legal framework and how the framework could be improved to simultaneously promote critical research and the welfare of child participants.
In this study we describe the sociodemographic characteristics of people participating in a clinical trial on the safety and immunogenicity of a H5N1 influenza vaccine and we identify the main motivations for joining it. PMID:22452976
Rocha, C L; Murillo, L A; Mora, A L; Rojas, M; Franco, L; Cote, J; Valero, M V; Moreno, A; Amador, R; Nuñez, F
The synthetic malaria vaccine SPf 66 has been shown to be safe, immunogenic and effective in trials performed with controlled groups naturally and experimentally exposed to the disease. In order to continue the trials in open populations, it was necessary to standardize the vaccination characteristics. We have performed four field trials with soldier volunteers with the aim, among others, of defining the number of doses required, the intervals between applications, the protein concentration, and the adjuvant to be used. In these trials, the vaccinated individuals' immune responses were evaluated by assaying anti-SPf 66 antibody titres, in vitro growth inhibition of the P. falciparum parasite, and the vaccinees' capacity to recognize P. falciparum native proteins. From these results we conclude that the best vaccination schedule, for adults, is three doses administered subcutaneously on days 0, 30 and 180, each containing 2 mg of the synthetic polymerized petide SPf 66 adsorbed to alum hydroxide.
Hagen, Kimberly Sessions
For African Americans, medical research often connotes exploitation and cruelty, making recruiting African Americans to participate in HIV vaccine trials particularly daunting. But infusing adult education principles into such efforts is both increasing African American participation and helping heal the legacy of the Tuskegee experiment.
Kegeles, Susan M.; Johnson, Mallory O.; Strauss, Ronald P.; Ralston, Brady; Hays, Robert B.; Metzger, David S.; McLellan-Lemal, Eleanor; MacQueen, Kathleen M.
Developing an effective vaccine remains a critical long-term approach to HIV prevention. Every efficacy trial should be responsive to the concerns of participating communities because the successful development of an HIV preventive vaccine will require long-term involvement of people who have been marginalized and who distrust the government and…
McMichael, Andrew J; Haynes, Barton F
A vaccine against human immunodeficiency virus (HIV) seems to be on the horizon. Correlates of risk of infection for the RV144 trial have been found. There is understanding of what makes HIV envelope–specific antibodies broadly neutralizing and new T cell vaccine approaches can overcome virus variability. PMID:22513323
Moulin, A M
Vaccine trials against Ebola virus have been conceived and organized, in August 2014, after the epidemic started in three countries of West Africa. If the preparedness had been missing, the planners tried to anticipate the resistance to vaccination, in Guinea, Sierra Leone and Liberia. This article offers a retrospective view on the resistances to vaccination throughout its history, from smallpox inoculation to anti-polio vaccine. Resistances have been linked to the political contexts and the rejection of an oppressive power, either local or foreign, as well as mistakes and scientific uncertainties. The analysis of the historical factors of resistance leads to reverse the question: what convinces people to accept a vaccine trial, despite the obscurities of the immunization processes inside the body? The article hypothesizes that Guineans and West Africans face a dilemma similar to their counterparts in the past, whether or not to rally to an experimental immunization, the results of which are still pending. They may appropriate the Western beliefs about the efficacy of vaccines to their own ways of circumventing misfortune. Further field studies will be required to assess the role of the vaccinal trials and the response to the epidemic in the "convalescence" of these societies, being aware that the trials will not allow a complete assessment of the vaccines, because of the end of the epidemic.
Dhungyel, O P; Lehmann, D R; Whittington, R J
Footrot is a contagious disease of ruminants requiring strains of Dichelobacter nodosus that possess virulence factors including proteases and fimbriae. Sheep can be immunised against footrot using vaccine-containing fimbriae, either native or recombinant. The fimbriae are responsible for the serological K-agglutination reaction, which has been used to classify field isolates into nine major serogroups. The range of protection conferred by vaccination is largely restricted to the serogroup involved, but antigenic competition precludes effective vaccination with multivalent vaccines that contain all serogroups. However, vaccination with specific bivalent recombinant fimbrial vaccine led to eradication of virulent footrot from small ruminants in Nepal and the same result was obtained in Bhutan using a specific whole cell vaccine. In the study reported here two pilot trials have been conducted in Australian sheep flocks, one with a virulent form of footrot caused by a single serogroup F, and the other with an intermediate form also caused by a single serogroup C. In trial 1 pre-vaccination prevalence of clinical footrot in a group of randomly selected animals was 44%. This reduced to 2% at 3 months and 0.5% at 4 months, and there were no clinical cases at 5 months or at 16 months post-vaccination in the whole flock. Similarly in trial 2 pre-vaccination whole flock prevalence was 8.5%, while it was 2% at 3 months, 0.3% at 6 months and zero at 18 months post-vaccination. Use of flock specific monovalent whole cell vaccines over whole flocks for only one season and culling of the few non-responders has been a successful approach in eradication of the disease from both these flocks. This is the first study to report the successful use of specific vaccine for the intermediate form of footrot.
Viseras, J; García-Fernández, P; Adroher, F J
Vaccines against Mediterranean theileriosis have been developed in several countries where this disease is of economic concern. Until recently, tissue culture vaccines were a suitable method for immunizing cattle and they have been widely applied with success. In Spain, Mediterranean theileriosis is an obstacle to the improvement of dairy cattle productivity. No vaccines against this disease have been applied until recently. This report concerns the field trial of an available experimental tissue culture vaccine consisting of attenuated Theileria annulata schizont infected cells from an enzootic area of Spain. The vaccinated cattle developed a typical post-vaccination immunological response and were resistent to a field challenge. They showed no clinical signs of theileriosis while 50% of the control cattle showed typical signs of the disease and two of them died (12.5% of control cattle). This vaccine may be useful to protect cattle against Mediterranean theileriosis in enzootic areas of Spain.
Defoort, Jean-Philippe; Nardelli, Bernardetta; Huang, Wolin; Ho, David D.; Tam, James P.
We describe a peptide vaccine model based on the mimicry of surface coat protein of a pathogen. This model used a macromolecular assemblage approach to amplify peptide antigens in liposomes or micelles. The key components of the model consisted of an oligomeric lysine scaffolding to amplify peptide antigens covalently 4-fold and a lipophilic membrane-anchoring group to further amplify noncovalently the antigens many-fold in liposomal or micellar form. A peptide antigen derived from the third variable domain of glycoprotein gp120 of human immunodeficiency virus type 1 (HIV-1), consisting of neutralizing, T-helper, and T-cytotoxic epitopes, was used in a macromolecular assemblage model (HIV-1 linear peptide amino acid sequence 308-331 in a tetravalent multiple antigen peptide system linked to tripalmitoyl-S-glycerylcysteine). The latter complex, in liposome or micelle, was used to immunize mice and guinea pigs without any adjuvant and found to induce gp120-specific antibodies that neutralize virus infectivity in vitro, elicit cytokine production, and prime CD8^+ cytotoxic T lymphocytes in vivo. Our results show that the macromolecular assemblage approach bears immunological mimicry of the gp120 of HIV virus and may lead to useful vaccines against HIV infection.
Voronin, Yegor; Zinszner, Helene; Karg, Carissa; Brooks, Katie; Coombs, Robert; Hural, John; Holt, Renee; Fast, Pat; Allen, Mary; Allen, Mary; Busch, Michael; Fast, Pat; Fruth, Ulrich; Golding, Hana; Khurana, Surender; Mulenga, Joseph; Peel, Sheila; Schito, Marco; Voronin, Yegor; Barnabas, Nomampondo; Bentsen, Christopher; Graham, Barney; Gray, Glenda; Levin, Andrew; McCluskey, Margaret; O'Connell, Robert; Snow, Bill; Ware, Mark
Antibody-inducing vaccines are a major focus in the preventive HIV vaccine field. Because the most common tests for HIV infection rely on detecting antibodies to HIV, they may also detect antibodies induced by a candidate HIV vaccine. The detection of vaccine-induced antibodies to HIV by serological tests is most commonly referred to as vaccine-induced sero-reactivity (VISR). VISR can be misinterpreted as a sign of HIV infection in a healthy study participant. In a participant who has developed vaccine-induced antibodies, accurate diagnosis of HIV infection (or lack thereof) may require specialized tests and algorithms (differential testing) that are usually not available in community settings. Organizations sponsoring clinical testing of preventive HIV vaccine candidates have an ethical obligation not only to inform healthy volunteers about the potential problems associated with participating in a clinical trial but also to help manage any resulting issues. This article explores the scope of VISR-related issues that become increasingly prevalent as the search for an effective HIV vaccine continues and will be paramount once a preventive vaccine is deployed. We also describe ways in which organizations conducting HIV vaccine trials have addressed these issues and outline areas where more work is needed. PMID:25649349
Buchner, D M; Larson, E B; White, R F
Available strategies to increase influenza vaccination rates in the elderly have not been tested in the private sector where most elderly receive care. We performed a randomized controlled trial of a postcard reminder in the three private general internal medicine practices. The observed vaccination rates of 55% in experimental patients (N = 262) and 54% in control patients (N = 278) were similar, though much higher than estimated national rates of 20%. The data indicated that the baseline (control group) vaccination rate was high probably because study participants were exposed to many community vaccination cues, separate from the study cue. That vaccination rates were not higher after additional exposure to the study cue suggests that a "ceiling effect" occurred. Including 70 patients not randomized into the trial because they received flu shots prior to randomization, the vaccination rate in patients who had a clinic visit during autumn months was 75% compared to a rate of 52% in patients not visiting the clinic (P less than .001). Our results suggest that vaccination rates can be considerably higher in the private sector than those reported in the past, and that both vaccination cues and direct patient contact appear important to promote vaccination. This and other studies suggest that traditional cues may have a ceiling effect, yielding vaccination rates no higher than 55 to 65%; further increases in rates will require other approaches.
Henderson, William G; Larson, Vernon D; Williams, David; Leuthke, Lynn
This article describes the organization and administration of the NIDCD/VA Hearing Aid Clinical Trial. The trial involved a total of 360 patients with bilateral, sensorineural hearing loss from eight VA Medical Centers to study three different hearing aid circuits in a three-period, three-treatment crossover design. Strong central coordination of such a complex multi-center clinical trial is essential to its success. The trial took more than 5 years to design, implement, and complete. This timeline is also described.
Shann, Frank; Nohynek, Hanna; Scott, J Anthony; Hesseling, Anneke; Flanagan, Katie L
The Expanded Program on Immunization (EPI) has led to large reductions in morbidity and mortality among children in low-income countries. However, the basic EPI schedule may no longer be optimal because of changes in vaccines, programs, and epidemiologic circumstances. In addition, evidence has accumulated that some EPI vaccines may have nonspecific effects that increase or decrease mortality from subsequent infections with other unrelated organisms. There is therefore a need for randomized trials to evaluate the effects of alternative EPI schedules on all-cause mortality, as well as vaccine efficacy against the target diseases. We have reviewed the available literature on the nonspecific effects of vaccines on mortality, and compiled a list of potential trials that might address this issue. We have then ranked the trials based on the potential importance of the results and the ethical and practical considerations. Trials of early BCG vaccination in low-birth-weight babies, early measles vaccination, and altered timing of DTP vaccination all have a high priority.
Ahmad, Sarfraz; Sweeney, Paul; Sullivan, Gerald C; Tangney, Mark
Development of various vaccines for prostate cancer (PCa) is becoming an active research area. PCa vaccines are perceived to have less toxicity compared with the available cytotoxic agents. While various immune-based strategies can elicit anti-tumour responses, DNA vaccines present increased efficacy, inducing both humoural and cellular immunity. This immune activation has been proven effective in animal models and initial clinical trials are encouraging. However, to validate the role of DNA vaccination in currently available PCa management paradigms, strong clinical evidence is still lacking. This article provides an overview of the basic principles of DNA vaccines and aims to provide a summary of preclinical and clinical trials outlining the benefits of this immunotherapy in the management of PCa.
Morris, C. Paul; Evans, Holly; Larsen, Sasha E.
SUMMARY Filarial worms cause highly morbid diseases such as elephantiasis and river blindness. Since the 1940s, researchers have conducted vaccine trials in 27 different animal models of filariasis. Although no vaccine trial in a permissive model of filariasis has provided sterilizing immunity, great strides have been made toward developing vaccines that could block transmission, decrease pathological sequelae, or decrease susceptibility to infection. In this review, we have organized, to the best of our ability, all published filaria vaccine trials and reviewed them in the context of the animal models used. Additionally, we provide information on the life cycle, disease phenotype, concomitant immunity, and natural immunity during primary and secondary infections for 24 different filaria models. PMID:23824365
Calzolari, A; Giraudo, J A; Rampone, H; Odierno, L; Giraudo, A T; Frigerio, C; Bettera, S; Raspanti, C; Hernández, J; Wehbe, M; Mattea, M; Ferrari, M; Larriestra, A; Nagel, R
A vaccine against bovine mastitis was developed. The vaccine was based on inactivated, highly encapsulated Staphylococcus aureus cells; a crude extract of Staph. aureus exopolysaccharides; and inactivated unencapsulated Staph. aureus and Streptococcus spp. cells. In this study, the vaccine was evaluated in 164 cows from two commercial dairies (A and B) during a 4-mo period. Two doses of the vaccine were administered subcutaneously to 82 cows in the brachiocephalicus muscle of the neck within a 4-wk interval. The results of this trial revealed significantly fewer intramammary infections caused by Staph. aureus at various levels of severity (clinical, subclinical, and latent) in cows that were vaccinated. The odds ratios of all types of intrammammary infections caused by Staph. aureus for dairies A and B, which were determined by a logistic model, were 1.84 and 1.89, respectively, for quarters of vaccinated cows and quarters of control cows. The colony counts for Staph. aureus in milk from infected quarters of vaccinated cows were significantly lower than those in milk from infected quarters of control cows. Also, the somatic cell counts per milliliter in milk from vaccinated cows were significantly decreased when the initial somatic cell count was < 500,000 cells/ml at the start of the trial. The vaccine had no observable effect on fat production in milk or on streptococcal infections.
Rid, Annette; Saxena, Abha; Baqui, Abdhullah H.; Bhan, Anant; Bines, Julie; Bouesseau, Marie-Charlotte; Caplan, Arthur; Colgrove, James; Dhai, Ames; Gomez-Diaz, Rita; Green, Shane K.; Kang, Gagandeep; Lagos, Rosanna; Loh, Patricia; London, Alex John; Mulholland, Kim; Neels, Pieter; Pitisuttithum, Punee; Sarr, Samba Cor; Selgelid, Michael; Sheehan, Mark; Smith, Peter G.
Vaccines are among the most cost-effective interventions against infectious diseases. Many candidate vaccines targeting neglected diseases in low- and middle-income countries are now progressing to large-scale clinical testing. However, controversy surrounds the appropriate design of vaccine trials and, in particular, the use of unvaccinated controls (with or without placebo) when an efficacious vaccine already exists. This paper specifies four situations in which placebo use may be acceptable, provided that the study question cannot be answered in an active-controlled trial design; the risks of delaying or foregoing an efficacious vaccine are mitigated; the risks of using a placebo control are justified by the social and public health value of the research; and the research is responsive to local health needs. The four situations are: (1) developing a locally affordable vaccine, (2) evaluating the local safety and efficacy of an existing vaccine, (3) testing a new vaccine when an existing vaccine is considered inappropriate for local use (e.g. based on epidemiologic or demographic factors), and (4) determining the local burden of disease. PMID:24768580
Wahid, Rahnuma; Holt, Renee; Hjorth, Richard; Berlanda Scorza, Francesco
With the support of the Biomedical Advanced Research and Development Authority (BARDA) of the US Department of Health and Human Services, PATH has contributed to the World Health Organization's (WHO's) Global Action Plan for Influenza Vaccines (GAP) by providing technical and clinical assistance to several developing country vaccine manufacturers (DCVMs). GAP builds regionally based independent and sustainable influenza vaccine production capacity to mitigate the overall global shortage of influenza vaccines. The program also ensures adequate influenza vaccine manufacturing capacity in the event of an influenza pandemic. Since 2009, PATH has worked closely with two DCVMs in Vietnam: the Institute of Vaccines and Medical Biologicals (IVAC) and VABIOTECH. Beginning in 2013, PATH also began working with Torlak Institute in Serbia; Instituto Butantan in Brazil; Serum Institute of India Private Ltd. in India; and Changchun BCHT Biotechnology Co. (BCHT) in China. The DCVMs supported under the GAP program all had existing influenza vaccine manufacturing capability and required technical support from PATH to improve vaccine yield, process efficiency, and product formulation. PATH has provided customized technical support for the manufacturing process to each DCVM based on their respective requirements. Additionally, PATH, working with BARDA and WHO, supported several DCVMs in the clinical development of influenza vaccine candidates progressing toward national licensure or WHO prequalification. As a result of the activities outlined in this review, several companies were able to make excellent progress in developing state-of-the-art manufacturing processes and completing early phase clinical trials. Licensure trials are currently ongoing or planned for several DCVMs.
Bonhoeffer, Jan; Imoukhuede, Egeruan B; Aldrovandi, Grace; Bachtiar, Novilia S; Chan, Eng-Soon; Chang, Soju; Chen, Robert T; Fernandopulle, Rohini; Goldenthal, Karen L; Heffelfinger, James D; Hossain, Shah; Jevaji, Indira; Khamesipour, Ali; Kochhar, Sonali; Makhene, Mamodikoe; Malkin, Elissa; Nalin, David; Prevots, Rebecca; Ramasamy, Ranjan; Sellers, Sarah; Vekemans, Johan; Walker, Kenneth B; Wilson, Pam; Wong, Virginia; Zaman, Khalequz; Heininger, Ulrich
This document is intended as a guide to the protocol development for trials of prophylactic vaccines. The template may serve phases I-IV clinical trials protocol development to include safety relevant information as required by the regulatory authorities and as deemed useful by the investigators. This document may also be helpful for future site strengthening efforts.
Cunha, Gilmara Holanda da; Galvão, Marli Teresinha Gimeniz; Medeiros, Camila Martins de; Rocha, Ryvanne Paulino; Lima, Maria Amanda Correia; Fechine, Francisco Vagnaldo
Antiretroviral therapy has increased the survival of patients with HIV/AIDS, thus necessitating health promotion practice with immunization. Vaccines are critical components for protecting people living with HIV/AIDS (PLWHA). The purpose of study was to analyze the vaccination status of PLWHA in outpatient care in Fortaleza, Ceará, Brazil. Cross-sectional study performed from June 2014 to June 2015. The screening was done with patients in antiretroviral therapy, 420 patients underwent screening, but only 99 met the inclusion criteria. Data were collected for interviews using forms to characterize sociodemographic, clinical and vaccination situations. Only 14 patients had complete vaccination schedules. The most used vaccines were hepatitis B, influenza vaccine and 23-valent pneumococcal. There was no difference between men and women regarding the proportion of PLWHA with full vaccination schedule or between sex, skin color, marital status, sexual orientation, religion or occupational status. There was no difference between having or not having a complete vaccination schedule and age, years of education, family income or number of hospitalizations. CD4+ T-cells count of patients with incomplete immunization was lower than patients with complete immunization. Health education strategies can be done individually or in groups to explain the importance of vaccination and to remind about doses to be administered. Most patients did not have proper adherence to vaccination schedules, especially due to lack of guidance. Results implied that education in health is important for vaccination adhesion, knowledge of adverse events and continuation of schemes.
Paitoonpong, Leilani; Suankratay, Chusana
Previous studies showed that an immunological response to hepatitis B virus (HBV) vaccination in patients with AIDS was lower than in the normal population. However, those with virological response to highly active antiretroviral therapy (HAART) may have a normal immunological response to HBV vaccination. In our study, patients with AIDS who had a virological response to HAART and no immunity to HBV received 3 doses of HBV vaccine (20 microg of Engerix-B(R)) on d 0, 30, and 180. Anti-HBs level was measured 1 month after complete vaccination. Of 28 patients, overall response rate to vaccination was 71.4%. The responder group had a significantly higher CD4 count at 1 month after complete vaccination than the non-responder group (466.95+/-146.94 and 335+/-112.62 cells/microl, p =0.035). The patients receiving efavirenz-containing HAART had better response than those without efavirenz-containing HAART (p =0.030). The responder group had received a longer duration of HAART. In conclusion , to our knowledge, ours is the first prospective study to determine the immunological response to HBV vaccination in all patients with AIDS who had maintained the virological response after receiving HAART throughout the study period. Patients with AIDS and virological response to HAART have a good immunological response to HBV vaccination.
Aznar, Inma; McGrath, Guy; Murphy, Denise; Corner, Leigh A L; Gormley, Eamonn; Frankena, Klaas; More, Simon J; Martin, Wayne; O'Keeffe, James; De Jong, Mart C M
The principal wildlife reservoir of Mycobacterium bovis in Ireland is the European badger. Studies in the Republic of Ireland (RoI) have shown that badgers culled in association with cattle herd tuberculosis breakdowns (focal culling) have a higher prevalence of infection than the badger population at large. This observation is one rationale for the medium term national strategy of focal badger culling. A vaccination strategy for the control of bovine tuberculosis (bTB) in badgers is a preferred long-term option. The Bacillus Calmette-Guérin (BCG) vaccine has been shown to decrease disease severity in captive badgers under controlled conditions. As the vaccine has been tested in a controlled environment with precise information on infection pressure, it cannot be assumed a priori that the effects of vaccination are similar in the wild, where other environmental and/or ecological factors prevail. For this reason we have designed a vaccine field trial to assess the impact of vaccination on the incidence of TB infection in a wild badger population. The selected study area for the vaccine trial (approximately 755 square kilometers) is divided into three zones each of which has similar characteristics in terms of size, number of main badger setts, cattle herds, cattle and land classification type. Three vaccination levels (100%, 50% and 0%) will be allocated to the three zones in a way that a gradient of vaccination coverage North to South is achieved. The middle zone (zone B) will be vaccinated at a 50% coverage but zone A and C will be randomly allocated with 100% or 0% vaccination coverage. Vaccination within zone B will be done randomly at individual badger level. The objective of this paper is to describe the design of a field tuberculosis vaccination trial for badgers, the epidemiological methods that were used to design the trial and the subsequent data analysis. The analysis will enable us to quantify the magnitude of the observed vaccination effect on M. bovis
Prior to the 1980s, most vaccines were licensed based upon safety and effectiveness studies in several hundred individuals. Beginning with the evaluation of Haemophilus influenzae type b conjugate vaccines, much larger pre-licensure trials became common. The pre-licensure trial for Haemophilus influenzae oligosaccharide conjugate vaccine had more than 60,000 children and that of the seven-valent pneumococcal conjugate vaccine included almost 38,000 children. Although trial sizes for both of these studies were driven by the sample size required to demonstrate efficacy, the sample size requirements for safety evaluations of other vaccines have subsequently increased. With the demonstration of an increased risk of intussusception following the Rotashield brand rotavirus vaccine, this trend has continued. However, routinely requiring safety studies of 20,000-50,000 or more participants has two major downsides. First, the cost of performing large safety trials routinely prior to licensure of a vaccine is very large, with some estimates as high at US$200 million euros for one vaccine. This high financial cost engenders an opportunity cost whereby the number of vaccines that a company is willing or able to develop to meet public health needs becomes limited by this financial barrier. The second downside is that in the pre-licensure setting, such studies are very time consuming and delay the availability of a beneficial vaccine substantially. One might argue that in some situations, this financial commitment is warranted such as for evaluations of the risk of intussusception following newer rotavirus vaccines. However, it must be noted that while an increased risk of intussusception was not identified in large pre-licensure studies, in post marketing evaluations an increased risk of this outcome has been identified. Thus, even the extensive pre-licensure evaluations conducted did not identify an associated risk. The limitations of large Phase III trials have also been
Mbunda, Theodora; Tarimo, Edith A. M.; Bakari, Muhammad; Sandström, Eric; Kulane, Asli
In sub-Saharan Africa, the burden of HIV is high among young people and it is of the utmost importance that they be recruited into vaccination trials. Since community members influence the willingness of young people to participate in the vaccination trials, ascertaining their opinions is essential to overcoming barriers to such participation. Here, in seven focus group discussions we explored the views of 44 community members identified as someone they felt close by youth in Tanzania. The transcripts of these discussions were examined using content analysis. Our participants expressed that community members would be directly involved in the decisions of young people about whether or not to participate in an HIV vaccine trial. In general, they felt that community members would provide social support for youth during the trial and perceived that youth might have misconceptions concerning the vaccine and trial process. The participants pointed out structural factors such as substance use, poverty, stigma and unemployment that are barriers to participation. In conclusion, involvement of community members could be an integral part of the recruitment and retention of young people in HIV vaccine trials in Tanzania. PMID:27997617
Buregyeya, Esther; Kulane, Asli; Kiguli, Juliet; Musoke, Phillipa; Mayanja, Harriet; Mitchell, Ellen Maeve Hanlon
Introduction Research is being carried out to develop and test new potentially more effective tuberculosis vaccines. Among the vaccines being developed are those that target adolescents. This study explored the stakeholders’ perceptions about adolescent participation in a hypothetical tuberculosis vaccine trial in Ugandan adolescents. Methods Focus group discussions with adolescents, parents of infants and adolescents, and key informant interviews with community leaders and traditional healers were conducted. Results The majority of the respondents expressed potential willingness to allow their children participate in a tuberculosis vaccine trial. Main motivations for potential participation would be being able to learn about health-related issues. Hesitations included the notion that trial participation would distract the youths from their studies, fear of possible side effects of an investigational product, and potential for being sexually exploited by researchers. In addition, bad experiences from participation in previous research and doubts about the importance of research were mentioned. Suggested ways to motivate participation included: improved clarity on study purpose, risks, benefits and better scheduling of study procedures to minimize disruption to participants’ academic schedules. Conclusion Findings from this study suggest that the community is open to potential participation of adolescents in a tuberculosis vaccine trial. However, there is a need to communicate more effectively with the community about the purpose of the trial and its effects, including safety data, in a low-literacy, readily understood format. This raises a challenge to researchers, who cannot know all the potential effects of a trial product before it is tested. PMID:26834929
Spencer, M J; Cherry, J D; Powell, K R; Sumaya, C V; Garakian, A J
Two clinical trials with Alice strain intranasal influenza vaccine were performed. In study no. 1 (utilizing random selection and double-blind control), 50 subjects received a bivalent inactivated influenza vaccine intramuscularly, 99 subjects received Alice strain vaccine intranasally, and 50 subjects received a placebo intranasally. No symptomatology could be attributed to the intranasal route of immunization. Convalescent-phase geometric mean titers of hemagglutination inhibition antibody were higher after intramuscular vaccination; seroconversion occurred in 16 or 17 recipients of the Alice strain, with initial titers of less than 1:8. Clinical and virologic surveillance for 20 weeks after vaccination revealed no influenza A illnesses in participants of the study. In study no. 2, 75% of the subjects with initial nasal antibody titers of less than 1:3 developed measurable nasal antibody after receiving Alice strain vaccine.
Okada, Masaji; Kita, Yoko; Hashimoto, Satomi; Nakatani, Hitoshi; Nishimastu, Shiho; Kioka, Yumiko; Takami, Yasuko
[Purpose] Multi-drug resistant (MDR), Mycobacterium tuberculosis (TB) is a big problem in the world. We have developed novel TB therapeutic vaccine (HVJ-E/HSP65 DNA +IL-12 DNA). [Methods and Results] DNA vaccine expressing TB heat shock protein 65 and IL-12 was delivered by the hemagglutinating virus of Japan (HVJ)-envelope. This vaccine provided remarkable protective efficacy and strong therapeutic efficacy against MDR-TB and XDR-TB in murine models. Furthermore, this vaccine provided therapeutic efficacy of prolongation of survival time of TB infected monkeys and augmented the immune responses. Therefore, the preclinical tests were studied for clinical trial. The injection of 100 μg of the vaccine /mouse i.m. three times in two weeks induced significantly strong production of IFN-γ and IL-2. 100 μg and 200 μg DNA vaccine/mouse i.m. augmented the production of these cytokines compared with 25 μg DNA vaccine/mouse i.m.. The ratio of 100 μg pDNA to 1AU HVJ-E enhanced the production of IFN-γ and IL-2. The decrease in the number of M. tuberculosis in liver of mice was observed by the vaccination of 100μg pDNA. By using these conditions, safety pharmacology study and toxicology test is being studied in monkeys administered by GMP level DNA vaccines. By the toxicology test using monkeys, high dose GMP level vaccine/ monkey is administrated. Safety pharmacological study of repeated administration is also being investigated in GLP level. Furthermore, we have planned to do clinical phase I trial. Targets are human patients with MDR-TB. The safety and tolerability of the vaccine will be evaluated. [Conclusion and recommendations] These data indicate that our novel vaccine might be useful against tuberculosis including XDR-TB and MDR-TB for human therapeutic clinical applications.
Muturi-Kioi, Vincent; Lewis, David; Launay, Odile; Leroux-Roels, Geert; Anemona, Alessandra; Loulergue, Pierre; Bodinham, Caroline L.; Aerssens, Annelies; Groth, Nicola; Saul, Allan; Podda, Audino
Background In the context of early vaccine trials aimed at evaluating the safety profile of novel vaccines, abnormal haematological values, such as neutropenia, are often reported. It is therefore important to evaluate how these trials should be planned not to miss potentially important safety signals, but also to understand the implications and the clinical relevance. Methodology We report and discuss the results from five clinical trials (two with a new Shigella vaccine in the early stage of clinical development and three with licensed vaccines) where the absolute neutrophil counts (ANC) were evaluated before and after vaccination. Additionally, we have performed a systematic review of the literature on cases of neutropenia reported during vaccine trials to discuss our results in a more general context. Principal Findings Both in our clinical trials and in the literature review, several cases of neutropenia have been reported, in the first two weeks after vaccination. However, neutropenia was generally transient and had a benign clinical outcome, after vaccination with either multiple novel candidates or well-known licensed vaccines. Additionally, the vaccine recipients with neutropenia frequently had lower baseline ANC than non-neutropenic vaccinees. In many instances neutropenia occurred in subjects of African descent, known to have lower ANC compared to western populations. Conclusions It is important to include ANC and other haematological tests in early vaccine trials to identify potential safety signals. Post-vaccination neutropenia is not uncommon, generally transient and clinically benign, but many vaccine trials do not have a sampling schedule that allows its detection. Given ethnic variability in the level of circulating neutrophils, normal ranges taking into account ethnicity should be used for determination of trial inclusion/exclusion criteria and classification of neutropenia related adverse events. Trial registration ClinicalTrials.gov NCT02017899
Aznar, I; More, S J; Frankena, K; De Jong, M C M
The aim of this study was to estimate the power, using simulation techniques, of a group randomized vaccine field trial designed to assess the effect of vaccination on Mycobacterium bovis transmission in badgers. The effects of sample size (recapture percentage), initial prevalence, sensitivity and specificity of the diagnostic test, transmission rate between unvaccinated badgers, Vaccine Efficacy for Susceptibility (VES) and Vaccine Efficacy for Infectiousness (VEI), on study power were determined. Sample size had a small effect on power. Study power increased with increasing transmission rate between non-vaccinated badgers. Changes in VES had a higher impact on power than changes in VEI. However, the largest effect on study power was associated with changes in the specificity of the diagnostic test, within the range of input values that were used for all other modelled parameters. Specificity values below 99.4% yielded a study power below 50% even when sensitivity was 100% and, VEI and VES were both equal to 80%. The effect of changes in sensitivity on study power was much lower. The results from our study are in line with previous studies, as study power was dependent not only on sample size but on many other variables. In this study, additional variables were studied, i.e. test sensitivity and specificity. In the current vaccine trial, power was highly dependent on the specificity of the diagnostic test. Therefore, it is critical that the diagnostic test used in the badger vaccine trial is optimized to maximize test specificity.
Hermsen, Cornelus C.; Sauerwein, Robert W.; de Vlas, Sake J.
Controlled human malaria infection (CHMI) in healthy human volunteers is an important and powerful tool in clinical malaria vaccine development. However, power calculations are essential to obtain meaningful estimates of protective efficacy, while minimizing the risk of adverse events. To optimize power calculations for CHMI-based malaria vaccine trials, we developed a novel non-linear statistical model for parasite kinetics as measured by qPCR, using data from mosquito-based CHMI experiments in 57 individuals. We robustly account for important sources of variation between and within individuals using a Bayesian framework. Study power is most dependent on the number of individuals in each treatment arm; inter-individual variation in vaccine efficacy and the number of blood samples taken per day matter relatively little. Due to high inter-individual variation in the number of first-generation parasites, hepatic vaccine trials required significantly more study subjects than erythrocytic vaccine trials. We provide power calculations for hypothetical malaria vaccine trials of various designs and conclude that so far, power calculations have been overly optimistic. We further illustrate how upcoming techniques like needle-injected CHMI may reduce required sample sizes. PMID:28081133
Park, Eunmi; Lee, Sunmin
Background This study aimed to evaluate the effect of a lay health worker (LHW) telephone intervention on completing a series of hepatitis B virus (HBV) vaccinations among foreign-born Asian Americans in the Baltimore-Washington Metropolitan area. Methods During the period of April 2013 and March 2014, we recruited Asian Americans who were 18 years of age and older in the community-based organizations. Of the 645 eligible participants, 600 (201 Chinese, 198 Korean, 201 Vietnamese) completed a pretest survey and received hepatitis B screening. Based on the screening results, we conducted a randomized controlled trial among those unprotected (HBsAg-/HBsAB-) by assigning them either to an intervention group (n = 124) or control group (n = 108). The intervention group received a list of resources by mails for where to get free vaccinations as well as reminder calls for vaccinations from trained LHWs, while the control group received only list of resources by mail. Seven months after mailing the HBV screening results, trained LHWs followed up with all participants by phone to ask how many of the recommended series of 3 vaccinations they had received: none, 1 or 2, or all 3 (complete). Their self-reported vaccinations were verified with the medical records. Multinomial logistic regressions were used to examine the effect of the LHW intervention. Process evaluation was conducted by asking study participants in the intervention group to evaluate the performance of the LHWs. Results After seven months, those in the intervention group were more likely to have 1 or more vaccines than the control group, compared to the no vaccination group (OR = 3.04, 95% CI, 1.16, 8.00). Also, those in the intervention group were more likely to complete a series of vaccinations than the control group, compared to the no vaccination group (OR = 7.29, 95% CI 3.39, 15.67). The most important barrier preventing them from seeking hepatitis B vaccinations was lack of time to get the vaccination
Huerta, M; de Aluja, A S; Fragoso, G; Toledo, A; Villalobos, N; Hernández, M; Gevorkian, G; Acero, G; Díaz, A; Alvarez, I; Avila, R; Beltrán, C; Garcia, G; Martinez, J J; Larralde, C; Sciutto, E
Taenia solium cysticercosis seriously affects human health when localised in the central nervous system (CNS) and causes great economic loss in pig husbandry in rural areas of endemic countries. Increasing the resistance to the parasite in the obligatory host pig may help in curbing transmission. Three synthetic peptides based on protein sequences of the murine parasite Taenia crassiceps, which had previously been shown to induce protection in mice against homologous challenge, were tested as a vaccine against T. solium cysticercosis in pigs. Vaccinated and unvaccinated piglets (240 in all) were distributed in pairs among the peasants' households of two rural villages in Mexico in which 14% of the native pigs were cysticercotic. Ten to twelve months later, the effect of vaccination was evaluated at necropsy. Vaccination decreased the total number of T. solium cysticerci (98.7%) and reduced the prevalence (52.6%). The natural challenge conditions used in this field trial strengthen the likelihood of successful transmission control to both pig and human through a large-scale pig vaccination program. We believe this is a major contribution in anticysticercosis vaccine development as these rather simple yet protective peptides are potentially more cost-effective to produce and less variable in results than antigens that are more complex.
Wahdan, M. H.; Sallam, S. A.; Hassan, M. N.; Abdel Gawad, A.; Rakha, A. S.; Sippel, J. E.; Hablas, R.; Sanborn, W. R.; Kassem, N. M.; Riad, S. M.; Cvjetanović, B.
The encouraging results of an earlier controlled field trial of the serogroup A meningococcal polysaccharide vaccine in the prevention of clinical disease prompted this study, the aim of which was to evaluate further the effectiveness of another lot of this type of vaccine, the duration of immunity, and the effectiveness against meningococcal carriage. A controlled field trial was carried out in early 1973 on 176 646 schoolchildren 6-15 years of age, of whom half received the serogroup A polysaccharide vaccine and the other half tetanus toxoid as a control. The incidence of cerebrospinal meningitis caused by serogroup A meningococci was 89% lower in the immunized group than in the controls for one year only. With regard to its effect on carriage, the vaccine was found to reduce to less than half the rate of new acquisition of serogroup A meningococci during the period immediately following immunization. The duration of the carrier state was also shortened in the immunized group. PMID:413639
Amador, R; Moreno, A; Murillo, L A; Sierra, O; Saavedra, D; Rojas, M; Mora, A L; Rocha, C L; Alvarado, F; Falla, J C
In the first field trial with synthetic malaria vaccine SPf66 in a large population naturally exposed to malaria, 9957 persons greater than 1 year old and residing on the Colombian Pacific coast received three doses of the vaccine. To evaluate vaccine safety, clinical observations were made 30 min and 48 h after each immunization. There were no adverse reactions in 95.7% of cases. In the 4.3% of cases with adverse reactions, local induration and erythema were the most frequent. In a randomly selected group of vaccinees, anti-SPf66 antibody titers were measured after the third dose: 93% of the vaccinees raised antibodies to SPf66. Among these, 55% had titers greater than 1:1600. These results demonstrate the safety and immunogenicity of the SPf66 vaccine in a large field trial.
White, Amina; Madhi, Shabir A
Many in the scientific community agree that a randomized, placebo-controlled trial would offer the most scientifically rigorous study design for establishing the efficacy of a Group B Streptococcus (GBS) vaccine administered to pregnant women for the prevention of invasive GBS disease in young infants. There are compelling reasons to conduct such a trial in low-middle income countries (LMICs) with a high burden of disease, such as South Africa, and to adopt an add-on trial design in which participants are randomized to receive the GBS vaccine or placebo in addition to the locally available standard of care. Yet there is a longstanding debate about whether trials in LMICs should offer participants the worldwide best available standard of care. In this article, we examine both the risk-benefit profile and the potential for exploitation with an add-on trial design in the context of the locally available standard of care in South Africa. Our analysis suggests that providing the local standard of care to participants in this case may be not only more scientifically valuable but also more ethically acceptable than attempting to provide the worldwide best available standard of care in the South African setting. Moreover, the example of GBS in the South African setting can help to elucidate important ethical considerations for determining the acceptability of testing vaccine efficacy in the context of locally available rather than the worldwide best available standard of care in Phase III trials of other new maternal vaccines.
Lankester, F.; Russell, G.C.; Lugelo, A.; Ndabigaye, A.; Mnyambwa, N.; Keyyu, J.; Kazwala, R.; Grant, D.; Percival, A.; Deane, D.; Haig, D.M.; Cleaveland, S.
Malignant catarrhal fever (MCF) is a fatal lymphoproliferative disease of cattle that, in East Africa, results from transmission of the causative virus, alcelaphine herpesvirus 1 (AlHV-1), from wildebeest. A vaccine field trial involving an attenuated AlHV-1 virus vaccine was performed over two wildebeest calving seasons on the Simanjiro Plain of northern Tanzania. Each of the two phases of the field trial consisted of groups of 50 vaccinated and unvaccinated cattle, which were subsequently exposed to AlHV-1 challenge by herding toward wildebeest. Vaccination resulted in the induction of virus-specific and virus-neutralizing antibodies. Some cattle in the unvaccinated groups also developed virus-specific antibody responses but only after the start of the challenge phase of the trial. PCR of DNA from blood samples detected AlHV-1 infection in both groups of cattle but the frequency of infection was significantly lower in the vaccinated groups. Some infected animals showed clinical signs suggestive of MCF but few animals went on to develop fatal MCF, with similar numbers in vaccinated and unvaccinated groups. This study demonstrated a baseline level of MCF-seropositivity among cattle in northern Tanzania of 1% and showed that AlHV-1 virus-neutralizing antibodies could be induced in Tanzanian zebu shorthorn cross cattle by our attenuated vaccine, a correlate of protection in previous experimental trials. The vaccine reduced infection rates by 56% in cattle exposed to wildebeest but protection from fatal MCF could not be determined due to the low number of fatal cases. PMID:26706270
Pitisuttithum, P; Migasena, S; Laothai, A; Suntharasamai, P; Kumpong, C; Vanichseni, S
Out of 91 volunteers enrolled for the HIV vaccine trial, only 33 volunteers were eligible for vaccination. Of 33 volunteers recruited, 59 per cent of them had incomes of more than 5,000 Baht/ month. The median duration of drug addicts was 15 years (range 1-26 years) and 42 per cent never used condoms during sexual intercourse. As far as consent comprehension was concerned, all of them understood.
Margolis, K L; Nichol, K L; Poland, G A; Pluhar, R E
Concern about side effects constitutes a major deterrent to patient compliance with influenza vaccination, yet there is a paucity of data about the occurrence of adverse reactions in the population targeted for immunization. We conducted a randomized, double-blind, crossover trial to compare the frequency of adverse reactions following administration of 1988-1989 trivalent split-antigen influenza vaccine and saline placebo. Outpatient veterans 65 years of age or over (n = 336) were recruited by mail and were randomly assigned to receive vaccine followed 2 weeks later by placebo injection or placebo followed 2 weeks later by vaccine. There was no significant difference between influenza vaccine and placebo with respect ot the proportion of subjects reporting disability or systemic symptoms.
Huang, Yunda; Karuna, Shelly T; Janes, Holly; Frahm, Nicole; Nason, Martha; Edlefsen, Paul T; Kublin, James G; Corey, Lawrence; McElrath, M Juliana; Gilbert, Peter B
Phase 1 preventive HIV vaccine trials are often designed as randomized, double-blind studies with the inclusion of placebo recipients. Careful consideration is needed to determine when the inclusion of placebo recipients is highly advantageous and when it is optional for achieving the study objectives of assessing vaccine safety, tolerability and immunogenicity. The inclusion of placebo recipients is generally important to form a reference group that ensures fair evaluation and interpretation of subjective study endpoints, or endpoints whose levels may change due to exposures besides vaccination. In some settings, however, placebo recipients are less important because other data sources and tools are available to achieve the study objectives.
French, Neil; Gordon, Stephen B; Mwalukomo, Thandie; White, Sarah A; Mwafulirwa, Gershom; Longwe, Herbert; Mwaiponya, Martin; Zijlstra, Eduard E; Molyneux, Malcolm E; Gilks, Charles F
Background: Streptococcus pneumoniae is a leading and serious co-infection of HIV-infected adults, particularly in Africa. Prevention of disease by vaccination with the current 23-valent polysaccharide vaccine is sub-optimal. Protein conjugate vaccines offer a further option for protection but no data exist on their clinical efficacy in any adult population. Methods: We conducted a double-blind randomized placebo-controlled clinical efficacy trial of the seven-valent conjugate pneumococcal vaccine in predominantly HIV-infected Malawian adults who had recovered from documented invasive pneumococcal disease (IPD). Vaccine was given as a two dose schedule four weeks apart. The primary end-point was a further episode of IPD caused by a vaccine-serotype or serotype-6A (VST/6A) pneumococcus. Results: Between February 2003 and October 2007, 496 individuals (44% male, 88% HIV seropositive) were followed for 798 person years of observation. There were 67 IPD events in 52 individuals, all in the HIV infected sub-group. There were 24 VST/6A events (19 VST, five 6A) in 24 participants, 5 in vaccine and 19 in the placebo recipients, a vaccine efficacy of 74% (95% CI 30% - 90%). There were 73 deaths in the vaccine arm and 63 in the placebo arm, Hazard Ratio 1.18 (95% confidence intervals 0.84 -1.66). Compared to placebo, serious adverse events were significantly lower (3 vs 17, p = 0.002) and minor adverse events significantly higher (41 vs 13, p = 0.003 ) in vaccine recipients. Conclusions: The seven-valent pneumococcal conjugate vaccine protects HIV infected adults from recurrent IPD of vaccine serotype or serotype 6A. PMID:20200385
Brayer, Jason; Lancet, Jeffrey E; Powers, John; List, Alan; Balducci, Lodovico; Komrokji, Rami; Pinilla-Ibarz, Javier
Peptide vaccines are capable of eliciting immune responses targeting tumor-associated antigens such as the Wilms' Tumor 1 (WT1) antigen, often overexpressed in myeloid malignancies. Here, we assessed the safety, tolerability, and immunogenicity of a polyvalent WT1 peptide vaccine. Individuals with WT1-positive acute myeloid leukemia (AML) in first (CR1) or second (CR2) remission or with higher-risk myelodysplastic syndrome (MDS) following at least 1 prior line of therapy were vaccinated with a mixture of peptides derived from the WT1 protein, with sargramostim injections before vaccination to amplify immunogenicity. Six vaccinations were delivered biweekly, continuing then monthly until patients received 12 vaccinations or showed disease relapse or progression. Therapeutic efficacy was evaluated by progression-free and overall survival. Immune responses were evaluated by delayed-type hypersensitivity testing and T-cell IFNγ ELISPOT at specified intervals. In 16 patients who received at least one vaccination, 10 completed the planned course of six vaccinations and six continued for up to six additional monthly vaccinations. Vaccinations were well tolerated, with no patients discontinuing due to toxicity. One of two patients with high-risk MDS experienced a prolonged decrease in transfusion dependence. Two of 14 AML patients demonstrated relapse-free survival >1 year. Both patients were in CR2 at time of vaccination, with duration of their remission exceeding duration of their first remission, suggesting a potential benefit. Our WT1 vaccine was well-tolerated. The clinical benefit that we observed in several patients suggests engagement of a protective immune response, indicating a need for further trials.
Sodora, Donald L; Allan, Jonathan S; Apetrei, Cristian; Brenchley, Jason M; Douek, Daniel C; Else, James G; Estes, Jacob D; Hahn, Beatrice H; Hirsch, Vanessa M; Kaur, Amitinder; Kirchhoff, Frank; Muller-Trutwin, Michaela; Pandrea, Ivona; Schmitz, Jörn E; Silvestri, Guido
The design of an effective AIDS vaccine has eluded the efforts of the scientific community to the point that alternative approaches to classic vaccine formulations have to be considered. We propose here that HIV vaccine research could greatly benefit from the study of natural simian immunodeficiency virus (SIV) infections of African nonhuman primates. Natural SIV hosts (for example, sooty mangabeys, African green monkeys and mandrills) share many features of HIV infection of humans; however, they usually do not develop immunodeficiency. These natural, nonprogressive SIV infections represent an evolutionary adaptation that allows a peaceful coexistence of primate lentiviruses and the host immune system. This adaptation does not result in reduced viral replication but, rather, involves phenotypic changes to CD4(+) T cell subsets, limited immune activation and preserved mucosal immunity, all of which contribute to the avoidance of disease progression and, possibly, to the reduction of vertical SIV transmission. Here we summarize the current understanding of SIV infection of African nonhuman primates and discuss how unraveling these evolutionary adaptations may provide clues for new vaccine designs that might induce effective immune responses without the harmful consequences of excessive immune activation.
Marangu, Diana; Kovacs, Stephanie; Walson, Judd; Bonhoeffer, Jan; Ortiz, Justin R.; John-Stewart, Grace; Horne, David J.
Introduction Wheeze is an important sign indicating a potentially severe adverse event in vaccine and drug trials, particularly in children. However, there are currently no consensus definitions of wheeze or associated respiratory compromise in randomized controlled trials (RCTs). Objective To identify definitions and severity grading scales of wheeze as an adverse event in vaccine and drug RCTs enrolling children <5 years and to determine their diagnostic performance based on sensitivity, specificity and inter-observer agreement. Methods We performed a systematic review of electronic databases and reference lists with restrictions for trial settings, English language and publication date ≥ 1970. Wheeze definitions and severity grading were abstracted and ranked by a diagnostic certainty score based on sensitivity, specificity and inter-observer agreement. Results Of 1,205 articles identified using our broad search terms, we identified 58 eligible trials conducted in 38 countries, mainly in high-income settings. Vaccines made up the majority (90%) of interventions, particularly influenza vaccines (65%). Only 15 trials provided explicit definitions of wheeze. Of 24 studies that described severity, 11 described wheeze severity in the context of an explicit wheeze definition. The remaining 13 studies described wheeze severity where wheeze was defined as part of a respiratory illness or a wheeze equivalent. Wheeze descriptions were elicited from caregiver reports (14%), physical examination by a health worker (45%) or a combination (41%). There were 21/58 studies in which wheeze definitions included combined caregiver report and healthcare worker assessment. The use of these two methods appeared to have the highest combined sensitivity and specificity. Conclusion Standardized wheeze definitions and severity grading scales for use in pediatric vaccine or drug trials are lacking. Standardized definitions of wheeze are needed for assessment of possible adverse events as
VanderWeele, Tyler J.; Tchetgen Tchetgen, Eric J.; Halloran, M. Elizabeth
Vaccination of one person may prevent the infection of another either because the vaccine prevents the first from being infected and from infecting the second, or because, even if the first person is infected, the vaccine may render the infection less infectious. We might refer to the first of these mechanisms as a contagion effect and the second as an infectiousness effect. In the simple setting of a randomized vaccine trial with households of size two, we use counterfactual theory under interference to provide formal definitions of a contagion effect and an unconditional infectiousness effect. Using ideas analogous to mediation analysis, we show that the indirect effect (the effect of one person’s vaccine on another’s outcome) can be decomposed into a contagion effect and an unconditional infectiousness effect on the risk-difference, risk-ratio, odds-ratio and vaccine-efficacy scales. We provide identification assumptions for such contagion and unconditional infectiousness effects, and describe a simple statistical technique to estimate these effects when they are identified. We also give a sensitivity-analysis technique to assess how inferences would change under violations of the identification assumptions. The concepts and results of this paper are illustrated with hypothetical vaccine-trial data. PMID:22828661
Jin, Xia; Morgan, Cecilia; Yu, Xuesong; DeRosa, Stephen; Tomaras, Georgia D; Montefiori, David C; Kublin, James; Corey, Larry; Keefer, Michael C
Plasmid DNA vaccines have been licensed for use in domesticated animals because of their excellent immunogenicity, but none have yet been licensed for use in humans. Here we report a retrospective analysis of 1218 healthy human volunteers enrolled in 10 phase I clinical trials in which DNA plasmids encoding HIV antigens were administered. Elicited T-cell immune responses were quantified by validated intracellular cytokine staining (ICS) stimulated with HIV peptide pools. HIV-specific binding and neutralizing antibody activities were also analyzed using validated assays. Results showed that, in the absence of adjuvants and boosting with alternative vaccines, DNA vaccines elicited CD8+ and CD4+ T-cell responses in an average of 13.3% (95% CI: 9.8-17.8%) and 37.7% (95% CI: 31.9-43.8%) of vaccine recipients, respectively. Three vaccinations (vs. 2) improved the proportion of subjects with antigen-specific CD8+ responses (p=0.02), as did increased DNA dosage (p=0.007). Furthermore, female gender and participants having a lower body mass index were independently associated with higher CD4+ T-cell response rate (p=0.001 and p=0.008, respectively). These vaccines elicited minimal neutralizing and binding antibody responses. These findings of the immunogenicity of HIV DNA vaccines in humans can provide guidance for future clinical trials.
Covering the Period 9/29/87 to 9/28/88 by 0Mark M . Manak and Linda Jagodzinski March 10, 1989 Supported by: US ARMY MEDICAL RESEARCH AND DEVELOPMENT...of Cytopathogenicity of Primate Lymphotropic Retroviruses: Relevance to Treatment and Vaccine for AIDS 12. PERSONAL AUTHOR(S) Manak, Mark M . and...1 hour. The mixture was adjusted to a pH >8.5 by the addition of 1 M TrisHCI, pH 9.0, and extracted three times with equal volumes of n-butanol. The
Jahnmatz, Maja; Amu, Sylvie; Ljungman, Margaretha; Wehlin, Lena; Chiodi, Francesca; Mielcarek, Nathalie; Locht, Camille; Thorstensson, Rigmor
Despite high vaccination coverage, pertussis is still a global concern in infant morbidity and mortality, and improved pertussis vaccines are needed. A live attenuated Bordetella pertussis strain, named BPZE1, was designed as an intranasal vaccine candidate and has recently been tested in man in a phase I clinical trial. Here, we report the evaluation of the B-cell responses after vaccination with BPZE1. Forty-eight healthy males with no previous pertussis-vaccination were randomized into one of three dose-escalating groups or into a placebo group. Plasma blast- and memory B-cell responses were evaluated by ELISpot against three different pertussis antigens: pertussis toxin, filamentous haemagglutinin and pertactin. Seven out of the 36 subjects who had received the vaccine were colonized by BPZE1, and significant increases in the memory B-cell response were detected against all three tested antigens in the culture-positive subjects between days 0 and 28 post-vaccination. The culture-positive subjects also mounted a significant increase in the filamentous haemagglutinin-specific plasma blast response between days 7 and 14 post-vaccination. No response could be detected in the culture-negatives or in the placebo group post-vaccination. These data show that BPZE1 is immunogenic in humans and is therefore a promising candidate for a novel pertussis vaccine. This trial is registered at ClinicalTrials.gov (NCT01188512).
Ölschläger, Stephan; Flatz, Lukas
Vaccination is one of the most valuable weapons against infectious diseases and has led to a significant reduction in mortality and morbidity. However, for most viral hemorrhagic fevers caused by arenaviruses, no prophylactic vaccine is available. This is particularly problematic as these diseases are notoriously difficult to diagnose and treat. Lassa fever is globally the most important of the fevers caused by arenaviruses, potentially affecting millions of people living in endemic areas, particularly in Nigeria. Annually, an estimated 300,000 humans are infected and several thousands succumb to the disease. The successful development of the vaccine “Candid#1” against Junin virus, the causative agent of Argentine hemorrhagic fever, proved that an effective arenavirus vaccine can be developed. Although several promising studies toward the development of a Lassa fever vaccine have been published, no vaccine candidate has been tested in human volunteers or patients. This review summarizes the immunology and other aspects of existing experimental arenavirus vaccine studies, discusses the reasons for the lack of a vaccine, and proposes a plan for overcoming the final hurdles toward clinical trials. PMID:23592977
Olschläger, Stephan; Flatz, Lukas
Vaccination is one of the most valuable weapons against infectious diseases and has led to a significant reduction in mortality and morbidity. However, for most viral hemorrhagic fevers caused by arenaviruses, no prophylactic vaccine is available. This is particularly problematic as these diseases are notoriously difficult to diagnose and treat. Lassa fever is globally the most important of the fevers caused by arenaviruses, potentially affecting millions of people living in endemic areas, particularly in Nigeria. Annually, an estimated 300,000 humans are infected and several thousands succumb to the disease. The successful development of the vaccine "Candid#1" against Junin virus, the causative agent of Argentine hemorrhagic fever, proved that an effective arenavirus vaccine can be developed. Although several promising studies toward the development of a Lassa fever vaccine have been published, no vaccine candidate has been tested in human volunteers or patients. This review summarizes the immunology and other aspects of existing experimental arenavirus vaccine studies, discusses the reasons for the lack of a vaccine, and proposes a plan for overcoming the final hurdles toward clinical trials.
Objective: Uptake of human papillomavirus (HPV) vaccinations by 17- to 18-year-old girls in England is below (<35%) target (80%). This trial assesses (a) the impact of financial incentives on uptake and completion of an HPV vaccination program, and (b) whether impacts are moderated by participants’ deprivation level. It also assesses the impact of incentives on decision quality to get vaccinated, as measured by attitudes toward the vaccination and knowledge of its consequences. Method: One thousand 16- to 18-year-old girls were invited to participate in an HPV vaccination program: 500 previously uninvited, and 500 unresponsive to previous invitations. Girls randomly received either a standard invitation letter or a letter including the offer of vouchers worth £45 (€56; $73) for undergoing 3 vaccinations. Girls attending their first vaccination appointment completed a questionnaire assessing decision quality to be vaccinated. Outcomes were uptake of the first and third vaccinations and decision quality. Results: The intervention increased uptake of the first (first-time invitees: 28.4% vs. 19.6%, odds ratio [OR] = 1.63, 95% confidence interval [CI; 1.08, 2.47]; previous nonattenders: 23.6% vs. 10.4%, OR = 2.65, 95% CI [1.61, 4.38]) and third (first-time invitees: 22.4% vs. 12%, OR = 2.15, 95% CI [1.32, 3.50]; previous nonattenders: 12.4% vs. 3%, OR = 4.28, 95% CI [1.92, 9.55]) vaccinations. Impacts were not moderated by deprivation level. Decision quality was unaffected by the intervention. Conclusions: Although the intervention increased completion of HPV vaccinations, uptake remained lower than the national target, which, in addition to cost effectiveness and acceptability issues, necessitates consideration of other ways of achieving it. PMID:25133822
Phanuphak, Nittaya; Lo, Ying-Ru; Shao, Yiming; Solomon, Sunil Suhas; O'Connell, Robert J.; Tovanabutra, Sodsai; Chang, David; Kim, Jerome H.
Abstract An overall decrease of HIV prevalence is now observed in several key Asian countries due to effective prevention programs. The decrease in HIV prevalence and incidence may further improve with the scale-up of combination prevention interventions. The implementation of future prevention trials then faces important challenges. The opportunity to identify heterosexual populations at high risk such as female sex workers may rapidly wane. With unabating HIV epidemics among men who have sex with men (MSM) and transgender (TG) populations, an effective vaccine would likely be the only option to turn the epidemic. It is more likely that efficacy trials will occur among MSM and TG because their higher HIV incidence permits smaller and less costly trials. The constantly evolving patterns of HIV-1 diversity in the region suggest close monitoring of the molecular HIV epidemic in potential target populations for HIV vaccine efficacy trials. CRF01_AE remains predominant in southeast Asian countries and MSM populations in China. This relatively steady pattern is conducive to regional efficacy trials, and as efficacy warrants, to regional licensure. While vaccines inducing nonneutralizing antibodies have promise against HIV acquisition, vaccines designed to induce broadly neutralizing antibodies and cell-mediated immune responses of greater breadth and depth in the mucosal compartments should be considered for testing in MSM and TG. The rationale and design of efficacy trials of combination prevention modalities such as HIV vaccine and preexposure prophylaxis (PrEP) remain hypothetical, require high adherence to PrEP, are more costly, and present new regulatory challenges. The prioritization of prevention interventions should be driven by the HIV epidemic and decided by the country-specific health and regulatory authorities. Modeling the impact and cost–benefit may help this decision process. PMID:26107771
... HUMAN SERVICES Centers for Disease Control and Prevention Community Preparation for Tuberculosis (TB..., , as amended. Purpose: The purpose of the program is for CDC to test new Tuberculosis (TB) vaccines... limited to, World Health Organization (WHO), International Union Against Tuberculosis and Lung...
Fiorentini, Simona; Giagulli, Cinzia; Caccuri, Francesca; Magiera, Anna K; Caruso, Arnaldo
The success in the development of anti-retroviral therapies (HAART) that contain human immunodeficiency virus type 1 (HIV-1) infection is challenged by the cost of this lifelong therapy and by its toxicity. Immune-based therapeutic strategies that boost the immune response against HIV-1 proteins or protein subunits have been recently proposed to control virus replication in order to provide protection from disease development, reduce virus transmission, and help limit the use of anti-retroviral treatments. HIV-1 matrix protein p17 is a structural protein that is critically involved in most stages of the life cycle of the retrovirus. Besides its well established role in the virus life cycle, increasing evidence suggests that p17 may also be active extracellularly in deregulating biological activities of many different immune cells that are directly or indirectly involved in AIDS pathogenesis. Thus, p17 might represent a promising target for developing a therapeutic vaccine as a contribution to combating AIDS. In this article we review the biological characteristics of HIV-1 matrix protein p17 and we describe why a synthetic peptide representative of the p17 functional epitope may work as a vaccine molecule capable of inducing anti-p17 neutralizing response against p17 derived from divergent HIV-1 strains.
Simuyandi, M.; Kapulu, M.
Summary We have observed previously that micronutrient supplementation ameliorated suppression of α‐defensin expression during diarrhoea. However, how interactions between anti‐microbial peptide (AMP) expression and diarrhoeal disease are altered by micronutrient supplementation remain unclear. Using oral vaccination as a model of intestinal infection, we measured changes in AMP expression during multiple micronutrient supplementation. In the first part, volunteers underwent duodenal jejunal biopsy before and at 1, 2, 4 or 7 days after administration of one of three live, attenuated oral vaccines against rotavirus, typhoid and enterotoxigenic Escherichia coli. In the second part, participants were randomized to receive a multiple micronutrient supplement or placebo for 6 weeks before undergoing intestinal biopsy, vaccination against typhoid and rebiopsy after 14 days. Expression of human alpha‐defensin (HD)5, HD6, hBD1, hBD2 and LL‐37 was measured by quantitative reverse transcription–polymerase chain reaction. Taken together, the bacterial vaccines, but not rotavirus vaccine, reduced HD5 expression (P = 0·02, signed‐rank test) and reduced LL‐37 expression in seven of the eight individuals whose biopsies had expression prevaccination (P = 0·03). hBD2 was not detected. In the controlled trial, HD5 and HD6 expression after vaccination was lower [median ratio 0·5, interquartile range (IQR) = 0·07–2·2 and 0·58, IQR = 0·13–2·3, respectively] than before vaccination. There was no significant effect detected of micronutrient supplementation on expression of HD5, HD6, hBD1 or LL‐37. We conclude that live attenuated bacterial vaccines, but not rotavirus vaccine, can reduce intestinal α‐defensins, and typhoid vaccine reduced LL‐37 expression. We found no evidence that micronutrient supplementation in the short term had any impact on anti‐microbial peptide expression. PMID:27465597
Shapiro, Stuart Z
The HIV cure agenda has rekindled interest in the development of a therapeutic HIV vaccine. An iterative clinical trial strategy that proved successful for the development of effective cancer chemotherapies in the 1960s may be applicable to the development of a CD8 T lymphocyte-based therapeutic HIV vaccine. However, while cancer chemotherapy development could begin with iterative clinical trials to improve the use of active drugs, the first step in therapeutic HIV vaccine design should be discovery of immunogen constructs with potential for activity and their optimization to meet the challenges of HIV-1 sequence diversity and human polymorphism in T cell antigen presentation. A strategy for doing this is discussed in this article. The proposed strategy relies on a major commitment by funding organizations to fund organized and coordinated manufacture and clinical testing of a series of first- and second-generation constructs to test basic concepts in product design. This is presented as an alternative to funding a more traditional competition among private manufacturers and product champions of individual, already designed products.
Cox, Lisa E.
This article presents data from an AIDS clinical trial that evaluated 238 (60 percent nonwhite) patients infected with HIV and their clinician's perceptions of medication adherence and visit attendance in relationship to lifestyle, psychosocial, and health belief model (HBM) variables. Twelve sites collected data via a prospective, multisite…
Lehtinen, Matti; Apter, Dan; Baussano, Iacopo; Eriksson, Tiina; Natunen, Kari; Paavonen, Jorma; Vänskä, Simopekka; Bi, Dan; David, Marie-Pierre; Datta, Sanjoy; Struyf, Frank; Jenkins, David; Pukkala, Eero; Garnett, Geoff; Dubin, Gary
High-risk human papillomaviruses (hrHPV) cause anogenital and oropharyngeal cancers. HPV-16/18 virus-like particle vaccine formulated with an AS04 adjuvant is very efficacious against hrHPV associated precancers but the herd effects of different vaccination scenarios are not known. Our cluster randomized trial (NCT00534638) assesses the overall and herd effects of vaccinating girls vs. girls and boys. In two school-years (2007-2008 and 2008-2009) we invited 80,272 1992-1995 born early adolescents to a CRT in 33 communities a priori stratified by low, intermediate and high HPV-16/18 seroprevalence. In 11 Arm A communities 90% of participating girls and boys were assigned to receive HPV-16/18 vaccine, in 11 Arm B communities 90% of girls were assigned to receive HPV-16/18 vaccine - boys were assigned to receive hepatitis B-virus (HBV) vaccine, and in 11 Arm C communities all were assigned to receive HBV-vaccine. Prevalence of HPV in vaccinated and unvaccinated girls is studied at age 18.5 years. Recruitment resulted in equal enrolment of four birth cohorts (born 1992-1995) comprising altogether 32,175 (40% response) early adolescents: 20,514 girls (50.5-53.0% response by arm) and 11,661 boys (21.9-31.6%% response by arm). At the age of 15 years, 79.3% of the vaccinees completed a questionnaire. Among them >98% were living at, and during the week-ends 1.3-1.6% stayed outside, the study site communities. Smoking habit and alcohol consumption were similar in the different trial arms, also mean-age of menarche (12.4 years) and 1st ejaculation (12.6 years), and sexual behaviour (among those <25%, who had had sexual debut) did not differ by arm: mean-age at the sexual debut 14.3 and 14.4 in girls and boys, and proportions of those with multiple (≥5) life-time sexual partners (6.5-7.5%) at the age of 15 years. Uniform residential, life-style and sexual behaviour characteristics indicate successful randomization/enrolment of the CRT. Our CRT will verify modelled
Beckett, Charmagne G; Tjaden, Jeffrey; Burgess, Timothy; Danko, Janine R; Tamminga, Cindy; Simmons, Monika; Wu, Shuenn-Jue; Sun, Peifang; Kochel, Tadeusz; Raviprakash, Kanakatte; Hayes, Curtis G; Porter, Kevin R
Candidate dengue DNA vaccine constructs for each dengue serotype were developed by incorporating pre-membrane and envelope genes into a plasmid vector. A Phase 1 clinical trial was performed using the dengue virus serotype-1 (DENV-1) vaccine construct (D1ME(100)). The study was an open-label, dose-escalation, safety and immunogenicity trial involving 22 healthy flavivirus-naïve adults assigned to one of two groups. Each group received three intramuscular injections (0, 1, and 5 months) of either a high dose (5.0mg, n=12) or a low dose (1.0mg, n=10) DNA vaccine using the needle-free Biojector(®) 2000. The most commonly reported solicited signs and symptoms were local mild pain or tenderness (10/22, 45%), local mild swelling (6/22, 27%), muscle pain (6/22, 27%) and fatigue (6/22, 27%). Five subjects (41.6%) in the high dose group and none in the low dose group developed detectable anti-dengue neutralizing antibodies. T-cell IFN gamma responses were detected in 50% (4/8) and 83.3% (10/12) of subjects in the low and high dose groups, respectively. The safety profile of the DENV-1 DNA vaccine is acceptable at both doses administered in the study. These results demonstrate a favorable reactogenicity and safety profile of the first in human evaluation of a DENV-1 DNA vaccine.
Brown, Scott A.; Surman, Sherri L.; Sealy, Robert; Jones, Bart G.; Slobod, Karen S.; Branum, Kristen; Lockey, Timothy D.; Howlett, Nanna; Freiden, Pamela; Flynn, Patricia; Hurwitz, Julia L.
Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of ‘original antigenic sin’ is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus) and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans. PMID:20407589
Nurkka, Anu; Lahdenkari, Mika; Palmu, Arto AI; Käyhty, Helena
Background Mucosal antibodies have been suggested to have a role in defence against pneumococcal infections. We investigated here the ability of a seven-valent pneumococcal conjugate vaccine, PncOMPC, to induce mucosal immune response. Methods Healthy Finnish children (n = 111), a subcohort of the Finnish Otitis Media Vaccine Trial, were recruited and 56 of them were immunised with the PncOMPC at the age of 2, 4, and 6 months. At 12 months of age, 49 of them received the PncOMPC and 7 were vaccinated with the pneumococcal polysaccharide vaccine (PncPS) as a booster. The control group of 55 children received a hepatitis B vaccine at the same ages. Salivary anti-Pnc IgG, IgA, IgA1, and IgA2 antibodies to serotypes 6B, 14, 19F, and 23F were measured in both groups at the age of 7 and 13 months. Results Salivary anti-Pnc IgG and IgA were detected more often in the PncOMPC than in the control group. However, the difference between groups was significant only for 19F and 23F IgA concentrations at the age of 7 months. At the age of 13 months, antibody concentrations did not differ between PncOMPC and control groups. The rises in IgA concentrations between 7 and 13 months of age were mainly of subclass IgA1. Further, there is a clear trend that PncPS booster induces higher salivary anti-Pnc PS antibody concentrations than the PncOMPC. Conclusion We found that PncOMPC can induce a mucosal IgA response. However, the actual impact of mucosal antibodies in protection against pneumococcal infections is not clear. PMID:15921511
Li, Shuying S; Gilbert, Peter B; Tomaras, Georgia D; Kijak, Gustavo; Ferrari, Guido; Thomas, Rasmi; Pyo, Chul-Woo; Zolla-Pazner, Susan; Montefiori, David; Liao, Hua-Xin; Nabel, Gary; Pinter, Abraham; Evans, David T; Gottardo, Raphael; Dai, James Y; Janes, Holly; Morris, Daryl; Fong, Youyi; Edlefsen, Paul T; Li, Fusheng; Frahm, Nicole; Alpert, Michael D; Prentice, Heather; Rerks-Ngarm, Supachai; Pitisuttithum, Punnee; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Robb, Merlin L; O'Connell, Robert J; Haynes, Barton F; Michael, Nelson L; Kim, Jerome H; McElrath, M Juliana; Geraghty, Daniel E
The phase III RV144 HIV-1 vaccine trial estimated vaccine efficacy (VE) to be 31.2%. This trial demonstrated that the presence of HIV-1-specific IgG-binding Abs to envelope (Env) V1V2 inversely correlated with infection risk, while the presence of Env-specific plasma IgA Abs directly correlated with risk of HIV-1 infection. Moreover, Ab-dependent cellular cytotoxicity responses inversely correlated with risk of infection in vaccine recipients with low IgA; therefore, we hypothesized that vaccine-induced Fc receptor-mediated (FcR-mediated) Ab function is indicative of vaccine protection. We sequenced exons and surrounding areas of FcR-encoding genes and found one FCGR2C tag SNP (rs114945036) that associated with VE against HIV-1 subtype CRF01_AE, with lysine at position 169 (169K) in the V2 loop (CRF01_AE 169K). Individuals carrying CC in this SNP had an estimated VE of 15%, while individuals carrying CT or TT exhibited a VE of 91%. Furthermore, the rs114945036 SNP was highly associated with 3 other FCGR2C SNPs (rs138747765, rs78603008, and rs373013207). Env-specific IgG and IgG3 Abs, IgG avidity, and neutralizing Abs inversely correlated with CRF01_AE 169K HIV-1 infection risk in the CT- or TT-carrying vaccine recipients only. These data suggest a potent role of Fc-γ receptors and Fc-mediated Ab function in conferring protection from transmission risk in the RV144 VE trial.
Pistorius, A G; van de Wijgert, J H H M; Sebola, M; Friedland, B; Nagel, E; Bokaba, C; Hoosen, A A
The Microbicide Division of the Department of Medical Microbiology at MEDUNSA, South Africa, recently completed a phase II expanded safety trial of the candidate microbicide Carraguard. A microbicide is a vaginal product that women might use, if proven safe and effective, to protect themselves from HIV and possibly other sexually transmitted infections (STIs). The study participants were from Ga-Rankuwa and its neighbouring areas, an historically disadvantaged residential township near Pretoria. We conducted six focus group discussions with phase II trial participants to evaluate their experiences with trial participation and their psychological needs. Participants spontaneously talked about their experiences with the study gel and speculum examinations. They felt that they had received high quality medical care. They indicated that their personal hygiene and knowledge of the female reproductive system, HIV and other STIs had improved, which helped their familie and empowered them as women. Participants valued being able to discuss their anxiety about HIV/AIDS wit study staff. They felt that the study provided them with a supportive environment in which their personal problems (not necessarily restricted to HIV/AIDS) could be addressed. Some recommended that the study staf improve their professionalism and punctuality. They suggested the formation of participant support groups, an expressed a preference to remain involved in the trial. Some participants appeared to have become dependent o services provided during the trial. We have taken the results of these focus group discussions into account during planning for a phase III efficacy trial of Carraguard to be conducted in the same and other similar communities.
Moldovan, Ioana R; Tary-Lehmann, Magdalena
The 9th Annual Vaccine Forum organized by Phacilitate in Washington D.C. 2011 brought together 50+ senior level speakers and over 400 participants representing all the key stakeholders concerning vaccines. The main focus of the meeting was to define priorities in the global vaccines sector from funding to manufacturing and evaluation of vaccine efficacy. A special session was devoted to improving immunogenicity, efficacy and safety of vaccines through innovation in clinical assay development and trial design. The current regulatory approach to clinical assay specification, validation and standardization that enable more direct comparisons of efficacy between trials was illustrated by the success in meningococcal vaccine development. The industry approach to validation strategies was exemplified by a new serologic test used on the diagnostic of pneumococcal pneumonia. The application of the Animal Rule to bridge clinical and non-clinical studies in botulism has allowed significant progress in developing one of the first vaccines to seek approval under the FDA Animal Efficacy Rule. An example of pushing the boundaries in the correlation of immunological responses and efficacy points was represented by a recent cell-based influenza vaccine for which the same correlates of protection apply as for the traditional, egg-based flue vaccine. In the field of HIV phase 2b studies are underway, based on promising results obtained with some vaccine candidates. The conclusion of this session was that creativity in vaccine design and evaluation is beneficial and can lead to innovative new vaccine designs as well as to validated assays to assess vaccine efficacy.
Nielsen, D.A.; Hamon, S.C.; Kosten, T.R.
Objectives We examined a pharmacogenetic association between a variant in the κ-opioid receptor (OPRK1) gene and the response to treatment with a cocaine vaccine tested in a recent clinical trial. This gene has a protective allele for opiate addiction that may act by inhibiting dopamine activation associated with reinforcement. Methods Sixty-nine DNA samples were obtained from 114 cocaine and opioid dependent subjects who were enrolled in a 16 week Phase IIb randomized double-blind placebo-controlled trial and who received five vaccinations over the first 12 weeks. We genotyped 66 of these subjects for the rs6473797 variant of the OPRK1 gene and we compared vaccine to placebo subjects in terms of cocaine-free urines over time. Results Using repeated measures analysis of variance, corrected for population structure, vaccine pharmacotherapy reduced cocaine positive urines significantly based on OPRK1 genotype. In subjects treated with the cocaine vaccine, those who were homozygous for the protective A allele of rs6473797 had the proportion of positive urines drop from 78% to 51% on vaccine (point-wise P < .0001, experiment-wise P <.005), while the positive urines of those individuals carrying the non-protective, risk G allele dropped from 82% to 77%. Strong interactions of treatment by SNP (single nucleotide polymorphism) reflected a lower baseline and significant reduction for placebo subjects with the risk G allele (P <0.00001). Conclusions This study indicates that a patient’s OPRK1 genotype could be used to identify a subset of individuals for which vaccine treatment may be an effective pharmacotherapy for cocaine dependence. PMID:23995774
Mwangoka, Grace; Ogutu, Bernhards; Msambichaka, Beverly; Mzee, Tutu; Salim, Nahya; Kafuruki, Shubis; Mpina, Maxmillian; Shekalaghe, Seif; Tanner, Marcel; Abdulla, Salim
Malaria vaccines are considered amongst the most important modalities for potential elimination of malaria disease and transmission. Research and development in this field has been an area of intense effort by many groups over the last few decades. Despite this, there is currently no licensed malaria vaccine. Researchers, clinical trialists and vaccine developers have been working on many approached to make malaria vaccine available.African research institutions have developed and demonstrated a great capacity to undertake clinical trials in accordance to the International Conference on Harmonization-Good Clinical Practice (ICH-GCP) standards in the last decade; particularly in the field of malaria vaccines and anti-malarial drugs. This capacity is a result of networking among African scientists in collaboration with other partners; this has traversed both clinical trials and malaria control programmes as part of the Global Malaria Action Plan (GMAP). GMAP outlined and support global strategies toward the elimination and eradication of malaria in many areas, translating in reduction in public health burden, especially for African children. In the sub-Saharan region the capacity to undertake more clinical trials remains small in comparison to the actual need.However, sustainability of the already developed capacity is essential and crucial for the evaluation of different interventions and diagnostic tools/strategies for other diseases like TB, HIV, neglected tropical diseases and non-communicable diseases. There is urgent need for innovative mechanisms for the sustainability and expansion of the capacity in clinical trials in sub-Saharan Africa as the catalyst for health improvement and maintained.
Norquist, Josephine M; Khawaja, Shazia S; Kurian, Cizely; Mast, T Christopher; Liaw, Kai-Li; Robertson, Michael N; Evans, Barbara; Gutsch, David; Saddier, Patricia
The Adult/Adolescent Vaccination Report Card (VRC) was developed and validated by Merck in 1998 for use in vaccine clinical trials to collect information from trial subjects on complaints for both local and systemic events after vaccination. This short report describes the revision to the original validated VRC in order to align with the guidelines outlined in the 2007 FDA Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials. Since the VRC elicits trial subjects' self-reports of any adverse experiences (AE) occurring post vaccination, it was important that subsequent modifications of the VRC retained the original user-friendly characteristics while gathering the appropriate information to align with the FDA Guidance. A convenience sample of 15 participants (71% females, 87% white and mean (SD) age 45 (13) years was recruited to obtain feedback in order to revise the Adult/Adolescent VRC. Based on the feedback received, the following were slightly revised: ruler for the measurements of local systemic reactions, severity ratings, and general instructions. The revised VRC is currently being used in Merck vaccine clinical trials.
Brown, Brandon; Davtyan, Mariam; Fisher, Celia B.
This study examined female sex workers’ evaluation of ethically relevant experiences of participating in an HPV4 vaccine clinical trial conducted in Lima, Peru (the Sunflower Study). The Sunflower Study provided all participants with HPV testing, treatment for those testing positive, and access to the vaccine for all testing negative. Themes that emerged from content analysis of interviews with 16 former participants included the importance of respectful treatment and access to healthcare not otherwise available and concerns about privacy protections, the potential for HIV stigma, and poststudy abandonment. PMID:27789934
Huang, Ying; Gilbert, Peter B; Fu, Rong; Janes, Holly
SummaryBiomarker endpoints measuring vaccine-induced immune responses are essential to HIV vaccine development because of their potential to predict the effect of a vaccine in preventing HIV infection. A vaccine's immune response profile observed in phase I immunogenicity studies is a key factor in determining whether it is advanced for further study in phase II and III efficacy trials. The multiplicity of immune variables and scientific uncertainty in their relative importance, however, pose great challenges to the development of formal algorithms for selecting vaccines to study further. Motivated by the practical need to identify a set of promising vaccines from a pool of candidate regimens for inclusion in an upcoming HIV vaccine efficacy trial, we propose a new statistical framework for the selection of vaccine regimens based on their immune response profile. In particular, we propose superiority and non-redundancy criteria to be achieved in down-selection, and develop novel statistical algorithms that integrate hypothesis testing and ranking for selecting vaccine regimens satisfying these criteria. Performance of the proposed selection algorithms are evaluated through extensive numerical studies. We demonstrate the application of the proposed methods through the comparison of immune responses between several HIV vaccine regimens. The methods are applicable to general down-selection applications in clinical trials.
Tatochenko, V K; Il'ina, N I; Romanenko, V V; Alikova, O A; Fassakhov, R S; Miasnikova, T N; Patlusova, V V; Zima, Iu Iu; Reshetnikova, I D; Frolova, G S; Smolenov, I V
Results of registration trial of combination vaccine for prevention of hepatitis A and B are presented. The trial was conducted in 5 centers of Russia in 2004-2005 with full accordance to good clinical practice requirements and standards for multicenter open randomized trials. Immunogenicity of studied combination vaccine Twinrix was evaluated in comparison with two simultaneously administered monovalent vaccines against hepatitis A and B (Havrix and Engerix-B) in 200 healthy subjects aged 18-40, which were seronegative to hepatitis A and B. Reactogenicity based on interviewed and non-interviewed symptoms ranged on intensity was assessed also. 1 month after completion of primary vaccination all subjects in both groups were seropositive to hepatitis A. Sero-protection level of antibodies to hepatitis B virus was detected in 98.9% of participants vaccinated with Twinrix and in 95.6% of participants vaccinated with Engerix-B and Havrix. Overall, reactogenicity of vaccines was minor, marked adverse events caused by vaccination were rare (approximately 1%). Study shows that combination vaccine against hepatitis A and B (Twinrix) at least non inferior in terms of immunogenicity, safety and tolerability to monovalent vaccines (Havrix and Engerix-B), were registered in Russia.
Van Donkersgoed, Joyce; Hancock, Dale; Rogan, Dragan; Potter, Andrew A
A feedlot trial was conducted to assess the efficacy of an Escherichia coli O157:H7 vaccine in reducing fecal shedding of E. coli O157:H7 in 218 pens of feedlot cattle in 9 feedlots in Alberta and Saskatchewan. Pens of cattle were vaccinated once at arrival processing and again at reimplanting with either the E. coli O157:H7 vaccine or a placebo. The E. coli O157:H7 vaccine included 50 microg of type III secreted proteins. Fecal samples were collected from 30 fresh manure patties within each feedlot pen at arrival processing, revaccination at reimplanting, and within 2 wk of slaughter. The mean pen prevalence of E. coli O157:H7 in feces was 5.0%; ranging in pens from 0% to 90%, and varying significantly (P < 0.001) among feedlots. There was no significant association (P > 0.20) between vaccination and pen prevalence of fecal E. coli O157:H7 following initial vaccination, at reimplanting, or prior to slaughter.
Bouma, A; Muljono, A Teguh; Jatikusumah, A; Nell, A J; Mudjiartiningsih, S; Dharmayanti, I; Siregar, E Sawitri; Claassen, I; Koch, G; Stegeman, J A
The aim of this field study was to determine the efficacy of vaccination against highly pathogenic avian influenza (HPAI) virus strain H5N1 in Indonesia. A limited, prototype clinical trial was performed using a standardised treatment group, in which poultry flocks were vaccinated at least twice with a selected H5N1 vaccine, and a control group comprising flocks treated with non-standardised procedures chosen by the farmer. Each group consisted of six flocks comprising either layers or native chickens. Haemagglutination inhibition (HI) antibody levels were determined by regular serum sampling, and outbreak surveillance relied on non-AI-vaccinated sentinel birds. After three vaccinations high antibody titres were produced in the treatment group, and the percentage of layers with an HI titre > 40 was approximately 90%. Although no conclusions can be drawn regarding reduction of virus transmission, this study demonstrated that 11 farms remained free from AI during the observation period, and that a surveillance programme based on differentiating infected from vaccinated animals (DIVA) can be implemented.
Janes, Holly; Gilbert, Peter; Buchbinder, Susan; Kublin, James; Sobieszczyk, Magdalena E; Hammer, Scott M
The HIV prevention landscape is evolving rapidly, and future efficacy trials of candidate vaccines, which remain the best long-term option for stemming the HIV epidemic, will be conducted in the context of partially effective nonvaccine prevention modalities. It is essential that these trials provide for valid and efficient evaluation of vaccine efficacy and immune correlates. The availability of partially effective prevention modalities presents opportunities to study their interactions with vaccines to maximally reduce HIV incidence. This article proposes an approach for conducting future vaccine efficacy trials in the context of background use of partially effective nonvaccine prevention modalities, and for conducting future vaccine efficacy trials that provide nonvaccine prevention modalities in one or more of the randomized study groups. Strategies are discussed for responding to emerging evidence on nonvaccine prevention modalities during ongoing vaccine trials. Next-generation HIV vaccine efficacy trials will almost certainly be more complex in their design and implementation but may become more relevant to at-risk populations and better suited to the ultimate goal of reducing HIV incidence at the population level.
Wheeler, David L.
Reports presented at the Sixth International Conference on Aids are summarized including efforts to develop a vaccine, expansion of the epidemic into new areas, the high rate of infection among Romanian children, the crisis in Africa, and evidence of relapsing behaviors among homosexual men in the United States. (MLW)
Befano, Brian L; Gonzalez, Paula; Rodríguez, Ana Cecilia; Herrero, Rolando; Schiller, John T; Kreimer, Aimée R; Schiffman, Mark; Hildesheim, Allan; Wilcox, Allen J
Objective To examine the effect of the bivalent human papillomavirus (HPV) vaccine on miscarriage. Design Observational long term follow-up of a randomized, double blinded trial combined with an independent unvaccinated population based cohort. Setting Single center study in Costa Rica. Participants 7466 women in the trial and 2836 women in the unvaccinated cohort enrolled at the end of the randomized trial and in parallel with the observational trial component. Intervention Women in the trial were assigned to receive three doses of bivalent HPV vaccine (n=3727) or the control hepatitis A vaccine (n=3739). Crossover bivalent HPV vaccination occurred in the hepatitis A vaccine arm at the end of the trial. Women in the unvaccinated cohort received (n=2836) no vaccination. Main outcome measure Risk of miscarriage, defined by the US Centers for Disease Control and Prevention as fetal loss within 20 weeks of gestation, in pregnancies exposed to bivalent HPV vaccination in less than 90 days and any time from vaccination compared with pregnancies exposed to hepatitis A vaccine and pregnancies in the unvaccinated cohort. Results Of 3394 pregnancies conceived at any time since bivalent HPV vaccination, 381 pregnancies were conceived less than 90 days from vaccination. Unexposed pregnancies comprised 2507 pregnancies conceived after hepatitis A vaccination and 720 conceived in the unvaccinated cohort. Miscarriages occurred in 451 (13.3%) of all exposed pregnancies, in 50 (13.1%) of the pregnancies conceived less than 90 days from bivalent HPV vaccination, and in 414 (12.8%) of the unexposed pregnancies, of which 316 (12.6%) were in the hepatitis A vaccine group and 98 (13.6%) in the unvaccinated cohort. The relative risk of miscarriage for pregnancies conceived less than 90 days from vaccination compared with all unexposed pregnancies was 1.02 (95% confidence interval 0.78 to 1.34, one sided P=0.436) in unadjusted analyses. Results were similar after adjusting for age at
Carter, C J Chris
Cross-reactive immunity occurs when infection with or vaccination against one virus protects against another related family member. A search for homologues of the HIV-1 envelope glycoprotein revealed that it is composed of thousands of intercalating and overlapping viral matches of pentapeptide or longer gapped consensi, belonging to over 70% of the currently sequenced virome, infecting all kingdoms from bacteria to man. It was also highly homologous to proteins from the Visna/Maedi and other ovine viruses, while other proteins (nef/tat/gag/pol) were homologous to proteins from the equine infectious anaemia virus and HTLV-2/HTLV-3 viruses. This phenomenon suggests that horizontal gene transfer from coinfecting RNA and DNA viruses to retroviruses is extensive, providing a route for the subsequent insertion of non-retroviral genes into human and other genomes via retroviral integration. This homology includes all viruses for which vaccines already exist. Cross-reactive immunity may be operative in AIDS, as Vaccinia vaccination decreases viral replication in HIV-1 infected patients' cells, for the CCR5 tropic form. Measles, Dengue virus, or GB virus C infections also decrease the HIV-1 viral load. A resumption of Vaccinia/smallpox vaccination might be expected to have a significant effect on the AIDS pandemic, and a careful study of the potential uses of other existing viral and bacterial vaccines merits close attention. This phenomenon may also be relevant to other recalcitrant viruses, bacteria, and parasites for which no vaccine exists and the armory of existing vaccines may have a role to play in diseases other than those for which they were designed.
Abi Mansour, Andrew; Sereda, Yuriy V; Yang, Jing; Ortoleva, Peter J
Simulations of virus-like particles needed for computer-aided vaccine design highlight the need for new algorithms that accelerate molecular dynamics. Such simulations via conventional molecular dynamics present a practical challenge due to the millions of atoms involved and the long timescales of the phenomena of interest. These phenomena include structural transitions, self-assembly, and interaction with a cell surface. A promising approach for addressing this challenge is multiscale factorization. The approach is distinct from coarse-graining techniques in that it (1) avoids the need for conjecturing phenomenological governing equations for coarse-grained variables, (2) provides simulations with atomic resolution, (3) captures the cross-talk between disturbances at the atomic and the whole virus-like particle scale, and (4) achieves significant speedup over molecular dynamics. A brief review of multiscale factorization method is provided, as is a prospective on its development.
Hounkpatin, Aurore B.; Schaumburg, Frieder; Ngoa, Ulysse Ateba; Esen, Meral; Fendel, Rolf; de Salazar, Pablo Martinez; Mürbeth, Raymund E.; Milligan, Paul; Imbault, Nathalie; Imoukhuede, Egeruan Babatunde; Theisen, Michael; Jepsen, Søren; Noor, Ramadhani A.; Okech, Brenda; Kremsner, Peter G.; Mordmüller, Benjamin
Background GMZ2 is a fusion protein of Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate rich protein (GLURP) that mediates an immune response against the blood stage of the parasite. Two previous phase I clinical trials, one in naïve European adults and one in malaria-exposed Gabonese adults showed that GMZ2 was well tolerated and immunogenic. Here, we present data on safety and immunogenicity of GMZ2 in one to five year old Gabonese children, a target population for future malaria vaccine efficacy trials. Methodology/Principal Findings Thirty children one to five years of age were randomized to receive three doses of either 30 µg or 100 µg of GMZ2, or rabies vaccine. GMZ2, adjuvanted in aluminum hydroxide, was administered on Days 0, 28 and 56. All participants received a full course of their respective vaccination and were followed up for one year. Both 30 µg and 100 µg GMZ2 vaccine doses were well tolerated and induced antibodies and memory B-cells against GMZ2 as well as its antigenic constituents MSP3 and GLURP. After three doses of vaccine, the geometric mean concentration of antibodies to GMZ2 was 19-fold (95%CI: 11,34) higher in the 30 µg GMZ2 group than in the rabies vaccine controls, and 16-fold (7,36) higher in the 100 µg GMZ2 group than the rabies group. Geometric mean concentration of antibodies to MSP3 was 2.7-fold (1.6,4.6) higher in the 30 µg group than in the rabies group and 3.8-fold (1.5,9.6) higher in the 100 µg group. Memory B-cells against GMZ2 developed in both GMZ2 vaccinated groups. Conclusions/Significance Both 30 µg as well as 100 µg intramuscular GMZ2 are immunogenic, well tolerated, and safe in young, malaria-exposed Gabonese children. This result confirms previous findings in naïve and malaria-exposed adults and supports further clinical development of GMZ2. Trial Registration ClinicalTrials.gov NCT00703066 PMID:21829466
Cross-sectional and longitudinal analysis of cancer vaccination trials registered on the US Clinical Trials Database demonstrates paucity of immunological trial endpoints and decline in registration since 2008
Lu, Liangjian; Yan, Haixi; Shyam-Sundar, Vijay; Janowitz, Tobias
Introduction Cancer vaccination has been researched as a means of treating and preventing cancer, but successful translational efforts yielding clinical therapeutics have been limited. Numerous reasons have been offered in explanation, pertaining both to the vaccine formulation, and the clinical trial methodology used. This study aims to characterize the tumor vaccine clinical trial landscape quantitatively, and explore the possible validity of the offered explanations including the translational obstacles posed by the current common endpoints. Methods We performed a detailed cross-sectional and longitudinal analysis of tumor vaccine trials (n=955) registered in the US Clinical Trials database. Results The number of tumor vaccine trials initiated per annum has declined 30% since a peak in 2008. In terms of vaccine formulation, 25% of trials use tumor cell/lysate preparations; whereas, 73% of trials vaccinate subjects against defined protein/peptide antigens. Also, 68% of trials do not use vectors for antigen delivery. Both these characteristics of tumor vaccines have remained unchanged since 1996. The top five types of cancer studied are: melanoma (22.6%); cervical cancer (13.0%); breast cancer (11.3%); lung cancer (9.5%); and prostate cancer (9.4%). In addition, 86% of the trials are performed where there is established disease rather than prophylactically, of which 67% are performed exclusively in the adjuvant setting. Also, 42% of Phase II trials do not measure any survival-related endpoint, and only 23% of Phase III trials assess the immune response to vaccination. Conclusion The clinical trial effort in tumor vaccination is declining, necessitating a greater urgency in identifying and removing the obstacles to clinical translation. These obstacles may include: 1) vaccination against a small range of antigens; 2) naked delivery of antigen; 3) investigation of less immunogenic cancer types; and 4) investigation in the setting of established disease. In addition
Moore, R Andrew; Wiffen, Philip J; Lipsky, Benjamin A
The objective was to review the evidence of effectiveness of the polyvalent polysaccharide pneumococcal vaccine from prospective properly randomised controlled trials comparing pneumococcal vaccines with placebo in subjects who are immunocompetent and those likely to have an impaired immune system. Databases searched included the Cochrane Library, (issue 2, 2000), MEDLINE (1966-August 2000), PubMed (to August 2000) and EMBASE ( to August 2000). Reference lists of reports and reviews were also searched. To be included in the analysis, a study had to have been a prospective randomised comparison of a polysaccharide pneumococcal vaccine (any valency) and to have a placebo or no treatment comparison group. Papers had to report important clinical outcomes, such as rates of pneumonia, pneumococcal pneumonia, lower respiratory tract infections, pneumonia deaths or bacteraemia. Serological outcomes were not sought. Thirteen randomised comparisons with over 45,000 subjects were identified in an extensive literature review. Eight studies had a quality score of 3 or more on a scale of 1 to 5. In three comparisons with 21,152 immunocompetent subjects (South African gold miners, New Guinea highlanders) pneumococcal vaccination was effective in reducing the incidence of all-cause pneumonia (relative risk 0.56, 95% confidence interval 0.47 to 0.66), pneumococcal pneumonia (0.16; 0.11 to 0.23), pneumonia deaths (0.70; 0.50 to 0.96) and bacteraemia (0.18; 0.09 to 0.34). In ten comparisons in over 24,000 people who were elderly or likely to have impaired immune systems, pneumococcal vaccination was without effect for any outcome. Present guidelines recommend pneumococcal vaccination for "high-risk" groups. There is no evidence from randomised trials that this is of any benefit. PMID:11038265
Newman, Peter A; Daley, Andrea; Halpenny, Roberta; Loutfy, Mona
Sustained recruitment over time of tens of thousands of clinical trial volunteers is essential to the development of safe and efficacious HIV vaccines. This study explored, in depth, reasons for declining to enroll among persons screened in as eligible for a Phase IIb prophylactic HIV vaccine trial. Thirteen non-enrollees completed a self-administered questionnaire; of those, 11 completed a 1-h follow-up interview. Interviews were transcribed verbatim and themes derived using narrative thematic analysis and NVivo software. Concerns about negative social consequences of false HIV-positive tests, trial uncertainties, side effects, double-blind assignment, trial duration, uncertain efficacy, behavioral disinhibition and stigma emerged as reasons for declining to enroll. Social, psychological and emotional dimensions of HIV vaccine trial participation--including false-positives and anticipated stigma and discrimination, possible impact on intimate relationships, and concerns about behavioral disinhibition--suggest that provision of voluntary trial-related psychosocial counseling, a trial ombudsperson, alternate trial sites, and systematic community engagement in trial planning, recruitment and evaluation may facilitate informed participation in safe and ethically conducted HIV vaccine trials.
This report summarizes the presentations and recommendations from a consultation held in Lausanne, Switzerland (26-28 August 2004) organized by the joint World Health Organization (WHO) - United Nations Programme on HIV/AIDS (UNAIDS) HIV Vaccine Initiative. The consultation discussed issues related to gender, ethnicity, and age in HIV vaccine research and clinical trial recruitment. A special focus of the meeting was the participation of women and adolescents in clinical trials. Also discussed were the experiences and lessons from various research programs, trials, and studies in different countries. Implementing the recommendations from this meeting will require prioritization and active participation from the research community, funders of research, local and national governments, non-governmental organizations, and industry, as well as the individuals and communities participating in clinical trials. This report contains the collective views of an international group of experts, and does not necessarily represent the decisions or the stated policy of the WHO. The contribution of the co-chairs (R. Macklin and F. Mhalu) and the rapporteurs (H. Lasher, M. Klein, M. Ackers, N. Barsdorf, A. Smith Rogers, E. Levendal, T. Villafana and M. Warren) during the consultation and in the preparation of this report is much appreciated. S. Labelle and J. Otani are also acknowledged and thanked for their efficient assistance in the preparation of the consultation and the report.
Andrasik, Michele Peake; Yoon, Ro; Mooney, Jessica; Broder, Gail; Bolton, Marcus; Votto, Teress; Davis-Vogel, Annet
Observed seroincidence and prevalence rates in male-to-female (MTF) transgender individuals highlight the need for effective targeted HIV prevention strategies for this community. In order to develop an effective vaccine that can be used by transgender women, researchers must understand and address existing structural issues that present barriers to this group's participation in HIV vaccine clinical trials. Overcoming barriers to participation is important for ensuring HIV vaccine acceptability and efficacy for the MTF transgender community. To explore barriers and facilitators to MTF transgender participation in preventive HIV vaccine clinical trials, the HIV Vaccine Trials Network conducted focus groups among transgender women in four urban areas (Atlanta, Boston, Philadelphia, and San Francisco). Barriers and facilitators to engagement of transgender women in preventive HIV vaccine clinical trials led to the following recommendations: (a) transgender cultural competency training, (b) creating trans-friendly environments, (c) true partnerships with local trans-friendly organizations and health care providers, (d) protocols that focus on transgender specific issues, and (e) data collection and tracking of transgender individuals. These results have implications for the conduct of HIV vaccine trials, as well as engagement of transgender women in research programs in general.
Yoon, Ro; Mooney, Jessica; Broder, Gail; Bolton, Marcus; Votto, Teress; Davis-Vogel, Annet
Observed seroincidence and prevalence rates in male to female (MTF) transgender individuals highlight the need for effective targeted HIV prevention strategies for this community. In order to develop an effective vaccine that can be used by transgender women, researchers must understand and address existing structural issues that present barriers to this group’s participation in HIV vaccine clinical trials. Overcoming barriers to participation is important for ensuring HIV vaccine acceptability and efficacy for the MTF transgender community. To explore barriers and facilitators to MTF transgender participation in preventive HIV vaccine clinical trials, the HIV Vaccine Trials Network (HVTN) conducted focus groups among transgender women in four urban areas (Atlanta, Boston, Philadelphia and San Francisco). Barriers and facilitators to engagement of transgender women in preventive HIV vaccine clinical trials led to the following recommendations: (1) transgender cultural competency training; (2) creating trans-friendly environments; (3) true partnerships with local trans-friendly organizations and health care providers; (4) protocols that focus on transgender specific issues; and (5) data collection and tracking of transgender individuals. These results have implications for the conduct of HIV vaccine trials, as well as engagement of transgender women in research programs in general. PMID:23446435
Klebsiella, Pseudomonas). Enterics, Foreign, Hepatitis A, Hepatitis B, Infectious Diseases , Vaccines, Biotechnology, ID, RA I Unclassified Unclassified...efficiency of these tri- als, and in order to effectively evaluate their efficacy, it was felt that serologic markers of evidence of previous disease and...of susceptibility to future disease should be studied. The cur- rent study on the seroepidemiology of shigellosis and hepatitis A was carried out as a
Wood, J M; Newman, R W; Daas, A; Terao, E; Buchheit, K-H
The Quality of Medicines & HealthCare (EDQM, Council of Europe) and the European Union (EU) Commission to evaluate the reproducibility of clinical serology results for seasonal influenza vaccines and to assess the impact of technical differences between laboratories on the compliance with the Committee for Human Medicinal Products (CHMP) criteria set by the European Medicines Agency (EMA). The study was run in 2 phases. The present article reports the 1st phase of the study, which aimed at evaluating the variability of the results obtained by 11 laboratories (5 national control laboratories and 6 influenza vaccine manufacturers) using their routine haemagglutination inhibition (HI) assay to test a common panel of clinical trial sera. The results confirmed the limited inter-laboratory reproducibility of the HI testing of influenza vaccine clinical trial samples. In some cases a good agreement was found between laboratories, while a systematic bias or a random scatter of results was observed in other cases. Analysis of estimated systematic bias confirmed that differences between laboratories can be significant (up to 16-fold) in some cases. Correction for this bias resulted in limited improvement. Differences between laboratories were found to result in discrepant decisions on marketing acceptance of vaccines or to decisions based on compliance to different criteria. The study showed that the seroconversion (SC) and mean fold increase (MFI) criteria are more robust against systematic over- or under-estimation of titres whereas the protection rate (PR) is very sensitive to this effect. The fundamental issues with the PR criteria are discussed.
Idoko, Olubukola T.; Diallo, Aldiouma; Sow, Samba O.; Hodgson, Abraham; Akinsola, Adebayo; Diarra, Bou; Haidara, Fadima Cheick; Ansah, Patrick Odum; Kampmann, Beate; Bouma, Enricke; Preziosi, Marie-Pierre; Enwere, Godwin C.
Background. The Meningitis Vaccine Project (MVP) was established to address epidemic meningitis as a public health problem in sub-Saharan Africa and, to that end, worked to develop a group A meningococcal conjugate vaccine, PsA-TT. Methods. Experiences in 4 clinical trial sites are described. Culturally sensitive collaborative strategies were adopted to manage acceptable communication methods, peculiarities with the consent process, participant medical issues, community care, and death. Results. The clinical trials were completed successfully through community acceptance and active community collaboration. The trials also strengthened the capacities in the participating communities, and actively worked to resolve community problems. Conclusions. The understanding and integration of sociocultural realities of communities were major assets in the conduct and acceptance of these trials. MVP succeeded in these sites and provided a sound example for future clinical studies in Africa. Clinical Trials Registration. ISRTCN78147026 (PsA-TT 002); ISRCTN87739946 (PsA-TT 003); ISRCTN82484612 (PsA-TT 004); PACTR ATMR2010030001913177 (PsA-TT 006); and PACTR201110000328305 (PsA-TT 007). PMID:26553669
Larrieu, Edmundo; Mujica, Guillermo; Gauci, Charles G.; Vizcaychipi, Katherina; Seleiman, Marcos; Herrero, Eduardo; Labanchi, José Luis; Araya, Daniel; Sepúlveda, Luis; Grizmado, Claudia; Calabro, Arnoldo; Talmon, Gabriel; Poggio, Thelma Verónica; Crowley, Pablo; Cespedes, Graciela; Santillán, Graciela; García Cachau, Mariela; Lamberti, Roberto; Gino, Lilia; Donadeu, Meritxell; Lightowlers, Marshall W.
Background Cystic echinococcosis (CE) is an important zoonotic disease caused by the cestode parasite Echinococcus granulosus. It occurs in many parts of the world where pastoral activities predominate, including the Rio Negro province of Argentina. Although CE control activities have been undertaken in the western regions of Rio Negro for more than two decades, the disease continues to remain prevalent in both the human and livestock animal populations. Vaccination of animal intermediate hosts of CE with the EG95 vaccine may provide a new opportunity to improve the effectiveness of CE control measures, although data are lacking about field application of the vaccine. Aims Evaluate the impact of EG95 vaccination in sheep on the transmission of Echinococcus granulosus in a field environment. Methodology Two trial sites were established in western Rio Negro province within indigenous communities. Vaccination of lambs born into one trial site was introduced and continued for 6 years. Prior to initiation of the trial, and at the end of the trial, the prevalence of CE in sheep was determined by necropsy. Weaned lambs received two injections of EG95 vaccine, approximately one month apart, and a single booster injection one year later. Vaccination was not implemented at the second trial site. A total of 2725 animals were vaccinated in the first year. Animals from this cohort as well as age-matched sheep from the control area were evaluated by necropsy. Key results Introduction of the vaccine led to a statistically significant in the number and size of hydatid cysts in comparison to the situation prior to the introduction of the vaccine, or compared to CE prevalence in the control area where the vaccine was not applied. The prevalence of infection in the vaccinated area was also significantly reduced by 62% compared to the re-intervention level, being lower than the prevalence seen in the control area, although the difference from the control area after the intervention
Chen, Jing Jing; Yuan, Lin; Huang, Zhen; Shi, Nian Min; Zhao, Yu Liang; Xia, Sheng Li; Li, Guo Hua; Li, Rong Cheng; Li, Yan Ping; Yang, Shu Yuan; Xia, Jie Lai
Introduction The invasive pneumococcal diseases (IPDs) caused by Streptococcus pneumoniae pose an enormous threat to children under 5 years of age. However, routine use of pneumococcal conjugate vaccines could aid in reducing the incidence of IPDs. The purpose of this clinical trial is to assess the non-inferiority of the investigational 13-valent pneumococcal conjugate vaccine (PCV13) to the currently licensed 7-valent pneumococcal conjugate vaccine (PCV7). Methods and analysis 1040 infants will receive a three-dose series of either PCV13 or PCV7 at ages 3, 4 and 5 months, respectively, and a booster dose at 12–15 months. Primary end points are the percentage of participants reaching a serotype-specific IgG concentration of ≥0.35 µg/mL and the IgG antibody geometric mean concentrations (GMCs) measured 30 days after the primary immunisation. Secondary end points include the percentage of vaccine recipients reaching a serotype-specific IgG concentration threshold of 1.0 µg/mL, the percentage of participants reaching the pneumococcal opsonophagocytic assay (OPA) titre threshold of 1:8, and the geometric mean titres (GMTs) of OPA measured 30 days after primary and booster doses. The number of standard IgG responders and IgG GMCs measured 30 days after the booster immunisation will also be determined. To evaluate differences between two groups, the sequential testing of the non-inferiority of PCV13 for the seven common serotypes and its effectiveness in treating the six additional serotypes will be performed. Ethics and dissemination Ethics approvals have been granted by the Ethics Committees at the three provinces involved in this study: Shanxi, Henan and Hebei. The trial will be reported in accordance with the CONSORT guidance. Trial registration number NCT02736240. PMID:27798013
Rudy, Bret J.; Kapogiannis, Bill G.; Lally, Michelle A.; Gray, Glenda E; Bekker, Linda-Gail; Krogstad, Paul; McGowan, Ian
Preventing HIV infection in adolescents and young adults will require a multimodal, targeted approach including individual-directed behavioral risk reduction, community-level structural change, and biomedical interventions to prevent sexual transmission. Trials testing biomedical interventions to prevent HIV transmission will require special attention in this population due to the unique psychosocial as well as physiologic characteristics that differentiate them from older populations. For example, microbicide research will need to consider acceptability, dosing requirements, and co-infection rates that are unique to this population. Pre-exposure prophylaxis studies also will need to consider potential unique psychosocial issues such as sexual disinhibition and acceptability as well as unique pharmacokinetic parameters of antiretroviral agents. Vaccine trials also face unique issues with this population, including attitudes towards vaccines, risks related to false-positive HIV tests related to vaccine, and different immune responses based on more robust immunity. In this paper, we will discuss issues around implementing each of these biomedical prevention modalities in trials among adolescents and young adults to help to guide future successful research targeting this population. PMID:20571421
Background Multiple myeloma is characterized by clonal expansion of B cells producing monoclonal immunoglobulins or fragments thereof, which can be detected in the serum and/or urine and are ideal target antigens for patient-specific immunotherapies. Methods Using phage particles as immunological carriers, we employed a novel chemically linked idiotype vaccine in a clinical phase I/II trial including 15 patients with advanced multiple myeloma. Vaccines composed of purified paraproteins linked to phage were manufactured successfully for each patient. Patients received six intradermal immunizations with phage idiotype vaccines in three different dose groups. Results Phage idiotype was well tolerated by all study participants. A subset of patients (80% in the middle dose group) displayed a clinical response indicated by decrease or stabilization of paraprotein levels. Patients exhibiting a clinical response to phage vaccines also raised idiotype-specific immunoglobulins. Induction of a cellular immune response was demonstrated by a cytotoxicity assay and delayed type hypersensitivity tests. Conclusion We present a simple, time- and cost-efficient phage idiotype vaccination strategy, which represents a safe and feasible patient-specific therapy for patients with advanced multiple myeloma and produced promising anti-tumor activity in a subset of patients. PMID:24885819
Téguété, Ibrahima; Dolo, Amadou; Sangare, Kotou; Sissoko, Abdoulaye; Rochas, Mali; Beseme, Sarah; Tounkara, Karamoko; Yekta, Shahla; De Groot, Anne S.; Koita, Ousmane A.
Background Cervical cancer is one of the most common and lethal cancers in West Africa. Even though vaccines that protect against the most common Human papillomavirus (HPV) strains, 16 and 18, are currently in use in developed countries, the implementation of these vaccines in developing countries has been painfully slow, considering the pre-eminence of HPV-associated cervical cancer among women in those countries. Aim We performed serological and PCR-based assessment of blood and tissue specimens obtained from women undergoing cervical cancer-related surgery at a major urban hospital in Bamako. Since several therapeutic HPV vaccines are currently in clinical trials, we also assessed willingness to participate in HPV cancer vaccine trials. Methods Blood and biopsy samples of 240 women were evaluated for HPV types 16 and 18 by serology and PCR. Knowledge regarding the HPV vaccine and autonomy to decide to vaccinate their own child was assessed with a standardized questionnaire. Results HPV 16 and 18 were identified in 137/166 (82.5%) cervical cancer biopsy samples by PCR. Co-infection with both HPV 16 and 18 was significantly more frequent in women over 50 years of age than in younger women (63.0% vs. 37.0%). 44% of study participants said they would be willing to vaccinate their child with HPV vaccine. Only 39% of women participating in this study reported that they would be able to make an autonomous decision to receive HPV vaccination. Permission from a male spouse or head of household was identified as important for participation by 59% of the women. Conclusion This study provides strong support for the introduction of currently available HPV vaccines in Mali, and also provides key information about conditions for obtaining informed consent for HPV vaccine trials and HPV vaccination in Mali. PMID:28231334
Smith, Kendall A; Andjelic, Sofija; Popmihajlov, Zoran; Kelly-Rossini, Liza; Sass, Aquanette; Lesser, Martin; Benkert, Steven; Waters, Cory; Ruitenberg, Joyce; Bellman, Paul
Objectives: To determine whether immunotherapy of chronic HIV-1 infection can prevent or attenuate viremia upon antiviral discontinuation. Design: This was a Phase II randomized, partially double blinded, 2×2 factorial study of three steps of 12 wk/step. Step I involved four groups: (1) vaccine placebo, (2) vaccine (ALVAC, vCP1452), (3) placebo + interleukin 2 (IL-2), and (4) vaccine + IL-2. Step II involved a 12-wk diagnostic treatment interruption (DTI). Step III involved an extension of the DTI for an additional 12 wk. Setting: The Weill-Cornell General Clinical Research Center. Participants: Chronically infected HIV-1 positive adults with undetectable HIV-1 levels and > 400 CD4+ T cells/μl. Interventions An HIV canarypox vaccine (vCP1452) and vaccine placebo, administered every 4 wk for four doses, and low-dose IL-2 administered daily for 12–24 wk. Outcome measures: Primary endpoints: (1) Proportion of participants with undetectable plasma HIV RNA during trial Step II, (2) mean log10 HIV RNA copies/ml ([HIV]) from weeks 21–25, and (3) proportion of individuals eligible for trial Step III. Results: 44 participants were randomized, but 16 withdrew or were withdrawn before completing Step II. As all participants underwent viral relapse in Step II, the study was terminated after 28 participants completed Step II. Among the four groups, there was no difference in mean [HIV] or the proportion of individuals with < log10 4.48 HIV; no difference between the mean [HIV] of the two groups that received ALVAC (n = 17) versus placebo (n = 11); and no significant difference between the mean [HIV] of the two groups that received IL-2 (n = 11) versus placebo (n = 17). Conclusions: Neither ALVAC (vCP1452) nor low-dose daily IL-2 nor their combination prevented the relapse of viremia upon discontinuation of antiviral therapy. PMID:17260026
Cagigi, Alberto; Pensieroso, Simone; Ruffin, Nicolas; Sammicheli, Stefano; Thorstensson, Rigmor; Pan-Hammarström, Qiang; Hejdeman, Bo; Nilsson, Anna; Chiodi, Francesca
The relevance of CD4+T-cells, viral load and age in the immunological response to influenza infection and vaccination in HIV-1 infected individuals has previously been pointed out. Our study aimed at assessing, in the setting of 2009 A(H1N1)pdm09 influenza vaccination, whether quantification of activation-induced deaminase (AID) expression in blood B-cells may provide additional indications for predicting antibody response to vaccination in HIV-1 infected patients with similar CD4+T-cell counts and age. Forty-seven healthy controls, 37 ART-treated and 17 treatment-naïve HIV-1 infected patients were enrolled in the study. Blood was collected prior to A(H1N1)pdm09 vaccination and at 1, 3 and 6 months after vaccination. Antibody titers to A(H1N1)pdm09 vaccine were measured by hemagglutination inhibition (HI) assay while the mRNA expression levels of AID were measured by quantitative real time PCR. Upon B-cell activation in vitro, AID increase correlated to antibody response to the A(H1N1)pdm09 vaccine at 1 month after vaccination in all individuals. In addition, the maximum expression levels of AID were significantly higher in those individuals who still carried protective levels of A(H1N1)pdm09 antibodies after 6 months from vaccination. No correlation was found between CD4+T-cell counts or age at vaccination or HIV-1 viral load and levels of A(H1N1)pdm09 antibodies. Assessing AID expression before vaccination may be an additional useful tool for defining a vaccination strategy in immune-compromised individuals at risk of immunization failure.
Gómez, Carmen Elena; Perdiguero, Beatriz; Jiménez, Victoria; Filali-Mouhim, Abdelali; Ghneim, Khader; Haddad, Elias K; Quakkelaar, Esther D; Quakkerlaar, Esther D; Delaloye, Julie; Harari, Alexandre; Roger, Thierry; Duhen, Thomas; Dunhen, Thomas; Sékaly, Rafick P; Melief, Cornelis J M; Calandra, Thierry; Sallusto, Federica; Lanzavecchia, Antonio; Wagner, Ralf; Pantaleo, Giuseppe; Esteban, Mariano
Based on the partial efficacy of the HIV/AIDS Thai trial (RV144) with a canarypox vector prime and protein boost, attenuated poxvirus recombinants expressing HIV-1 antigens are increasingly sought as vaccine candidates against HIV/AIDS. Here we describe using systems analysis the biological and immunological characteristics of the attenuated vaccinia virus Ankara strain expressing the HIV-1 antigens Env/Gag-Pol-Nef of HIV-1 of clade C (referred as MVA-C). MVA-C infection of human monocyte derived dendritic cells (moDCs) induced the expression of HIV-1 antigens at high levels from 2 to 8 hpi and triggered moDCs maturation as revealed by enhanced expression of HLA-DR, CD86, CD40, HLA-A2, and CD80 molecules. Infection ex vivo of purified mDC and pDC with MVA-C induced the expression of immunoregulatory pathways associated with antiviral responses, antigen presentation, T cell and B cell responses. Similarly, human whole blood or primary macrophages infected with MVA-C express high levels of proinflammatory cytokines and chemokines involved with T cell activation. The vector MVA-C has the ability to cross-present antigens to HIV-specific CD8 T cells in vitro and to increase CD8 T cell proliferation in a dose-dependent manner. The immunogenic profiling in mice after DNA-C prime/MVA-C boost combination revealed activation of HIV-1-specific CD4 and CD8 T cell memory responses that are polyfunctional and with effector memory phenotype. Env-specific IgG binding antibodies were also produced in animals receiving DNA-C prime/MVA-C boost. Our systems analysis of profiling immune response to MVA-C infection highlights the potential benefit of MVA-C as vaccine candidate against HIV/AIDS for clade C, the prevalent subtype virus in the most affected areas of the world.
Etcheverry, M Florencia; Lum, Paula J; Evans, Jennifer L; Sanchez, Emilia; de Lazzari, Elisa; Mendez-Arancibia, Eva; Sierra, Ernesto; Gatell, José M; Page, Kimberly; Joseph, Joan
Being able to recruit high-risk volunteers who are also willing to consider future participation in vaccine trials are critical features of vaccine preparedness studies. We described data from two cohorts of injection- and non-injection drug users in Barcelona, Spain [Red Cross centre] and in San Francisco, USA, [UFO-VAX study] at high risk of HIV/HCV infection to assess behaviour risk exposure and willingness to participate in future preventive HIV vaccine trials. We successfully identified drug-using populations that would be eligible for future HIV vaccine efficacy trials, based on reported levels of risk during screening and high levels of willingness to participate. In both groups, Red Cross and UFO-VAX respectively, HCV infection was highly prevalent at baseline (41% and 34%), HIV baseline seroprevalence was 4.2% and 1.5%, and high levels of willingness were seen (83% and 78%).
Etcheverry, M. Florencia; Lum, Paula J.; Evans, Jennifer L.; Sanchez, Emilia; de Lazzari, Elisa; Mendez-Arancibia, Eva; Sierra, Ernesto; Gatell, José M.; Page, Kimberly; Joseph, Joan
Being able to recruit high-risk volunteers who are also willing to consider future participation in vaccine trials are critical features of vaccine preparedness studies. We described data from two cohorts of injection- and non-injection drug users in Barcelona, Spain [Red Cross centre] and in San Francisco, USA, [UFO-VAX study] at high risk of HIV/HCV infection to assess behaviour risk exposure and willingness to participate in future preventive HIV vaccine trials. We successfully identified drug-using populations that would be eligible for future HIV vaccine efficacy trials, based on reported levels of risk during screening and high levels of willingness to participate. In both groups, Red Cross and UFO-VAX respectively, HCV infection was highly prevalent at baseline (41% and 34%), HIV baseline seroprevalence was 4.2% and 1.5%, and high levels of willingness were seen (83% and 78%). PMID:21241735
Islam, Dilara; Chamnanchanunt, Supat; Ruamsap, Nattaya; Khantapura, Patchariya; Kaewkungwal, Jaranit; Kittitrakul, Chatporn; Luvira, Viravarn; Dhitavat, Jittima; Venkatesan, Malabi M.; Mason, Carl J.; Bodhidatta, Ladaporn
Live attenuated Shigella sonnei vaccine candidate WRSS1, previously tested in U.S. and Israeli volunteers, was evaluated in a population of adult Thai volunteers in which the organism is endemic. In a randomized placebo-controlled, double-blind design, inpatient participants received a single oral dose of 1.6 × 104 CFU of WRSS1. The vaccine was generally well tolerated, with equal numbers of vaccinees and placebo controls showing mild symptoms. Only 3 of 13 vaccinees (23%) had culture-positive stools, while a total of 9 vaccinees were positive by PCR. Lack of vaccine shedding in volunteers correlated with lack of clinical symptoms and immune responses, just as the duration of fecal shedding correlated directly with stronger immune responses. Two months following immunization, 10 vaccinees and 10 newly recruited naive controls received a challenge dose of 1,670 CFU of virulent S. sonnei strain 53G. This dose had previously demonstrated a 75% attack rate for dysentery in Thai volunteers. However, in this study the attack rate for dysentery in naive controls after challenge was 20%. Based on clinical record summaries, 3 vaccinees and 5 naive controls experienced clinically relevant illness (diarrhea/dysentery/fever/shigellosis), and a 40% vaccine efficacy was calculated. When these data are compared to those for the performance of this vaccine candidate in more naive populations, it is clear that a single oral dose of WRSS1 at 104 CFU failed to achieve its full potential in a population in which the organism is endemic. Higher doses and/or repeated immunizations may contribute to improved vaccine shedding and consequent elevation of protective immune responses in a population in which the organism is endemic. (The study has been registered at ClinicalTrials.gov under registration no. NCT01080716.) PMID:27146000
McQuaid, Fiona; Stevens, Zoe; Plumb, Jane; Hughes, Rhona; Voysey, Merryn; Heath, Paul T; Snape, Matthew D
Objectives To explore factors influencing the likelihood of antenatal vaccine acceptance of both routine UK antenatal vaccines (influenza and pertussis) and a hypothetical group B Streptococcus (GBS) vaccine in order to improve understanding of how to optimise antenatal immunisation acceptance, both in routine use and clinical trials. Setting An online survey distributed to women of childbearing age in the UK. Participants 1013 women aged 18–44 years in England, Scotland and Wales. Methods Data from an online survey conducted to gauge the attitudes of 1013 women of childbearing age in England, Scotland and Wales to antenatal vaccination against GBS were further analysed to determine the influence of socioeconomic status, parity and age on attitudes to GBS immunisation, using attitudes to influenza and pertussis vaccines as reference immunisations. Factors influencing likelihood of participation in a hypothetical GBS vaccine trial were also assessed. Results Women with children were more likely to know about each of the 3 conditions surveyed (GBS: 45% vs 26%, pertussis: 79% vs 63%, influenza: 66% vs 54%), to accept vaccination (GBS: 77% vs 65%, pertussis: 79% vs 70%, influenza: 78% vs 68%) and to consider taking part in vaccine trials (37% vs 27% for a hypothetical GBS vaccine tested in 500 pregnant women). For GBS, giving information about the condition significantly increased the number of respondents who reported that they would be likely to receive the vaccine. Health professionals were the most important reported source of information. Conclusions Increasing awareness about GBS, along with other key strategies, would be required to optimise the uptake of a routine vaccine, with a specific focus on informing women without previous children. More research specifically focusing on acceptability in pregnant women is required and, given the value attached to input from healthcare professionals, this group should be included in future studies. PMID:27098824
Singh, Dinesh K; Liu, Zhenqian; Sheffer, Darlene; Mackay, Glenn A; Smith, Marilyn; Dhillon, Sukhbir; Hegde, Ramakrishna; Jia, Fenglan; Adany, Istvan; Narayan, Opendra
Simian/human immunodeficiency virus SHIV(KU2) replicates with extremely high titers in macaques. In order to determine whether the DNA of the viral genome could be used as a vaccine if the DNA were rendered noninfectious, we deleted the reverse transcriptase gene from SHIVKU2 and inserted this DNA (DeltartSHIVKU2) into a plasmid that was then used to test gene expression and immunogenicity. Transfection of Jurkat and human embryonic kidney epithelial (HEK 293) cells with the DNA resulted in production of all of the major viral proteins and their precursors and transient export of a large quantity of the Gag p27 into the supernatant fluid. As expected, no infectious virus was produced in these cultures. Four macaques were injected intradermally with 2 mg of the DNA at 0, 8, and 18 weeks. The animals developed neutralizing antibodies and low enzyme-linked immunospot assay (E-SPOT) titers against SHIVKU2. These four animals and two unvaccinated control animals were then challenged with heterologous SHIV89.6P administered into their rectums. The two control animals developed viral RNA titers exceeding 10(6) copies/ml of plasma, and these titers were accompanied by the loss of CD4+ T cells by 2 weeks after challenge. The two control animals died at weeks 8 and 16, respectively. All four of the immunized animals became infected with the challenge virus but developed lower titers of viral RNA in plasma than the control animals, and the titers decreased over time in three of the four macaques. The fourth animal remained viremic and died at week 47. Whereas the control animals failed to develop E-SPOT responses, all four of the immunized animals developed anamnestic E-SPOT responses after challenge. The animal that died developed the highest E-SPOT response and was the only one that produced neutralizing antibodies against the challenge virus. These results established that noninfectious DNA of pathogenic SHIV could be used as a vaccine to prevent AIDS, even though the
10-1-0699 TITLE: Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural Mesothelioma after...Prescribed by ANSI Std. Z39.18 W81XWH-10-1-0699 Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant... peptides that are given together with Montanide and GM-CSF as immunologic adjuvants. This WT1 vaccine was previously tested in a small pilot trial
In a controlled field trial on some 584 000 people in an endemic cholera El Tor area in the Philippines, it was demonstrated that cholera vaccines gave moderate protection of short duration. Injection of a single dose of vaccine prepared from either Vibrio cholerae or Vibrio El Tor gave over 50% protection for the first two months. The immunity conferred by the V. cholerae vaccine rapidly declined after three to four months. The V. El Tor vaccine gave protection for six months, but its effectiveness declined. An oil-adjuvant vaccine prepared from V. cholerae conferred an increasing degree of protection of long duration, but, owing to severe vaccination reactions, its use could not be recommended. PMID:5294176
Azurin, J. C.; Cruz, A.; Pesigan, T. P.; Alvero, M.; Camena, T.; Suplido, R.; Ledesma, L.; Gomez, C. Z.
A controlled field trial on some 584 000 people in an endemic cholera El Tor area in the Philippines demonstrated that cholera vaccines gave moderate protection of short duration. Injection of a single dose of vaccine prepared from either Vibrio cholerae or El Tor vibrios gave over 50% protection for the first 2 months. The immunity conferred by the V. cholerae vaccine declined rapidly after 3 to 4 months. The effectiveness of the El Tor vaccine continued for 6 months. An oil-adjuvant vaccine prepared from V. cholerae conferred an equally high degree of protection for a longer period of time, but, owing to severe vaccination reactions, its use could not be recommended. PMID:5300874
Smith, Steven G; Smits, Kaatje; Joosten, Simone A; van Meijgaarden, Krista E; Satti, Iman; Fletcher, Helen A; Caccamo, Nadia; Dieli, Francesco; Mascart, Francoise; McShane, Helen; Dockrell, Hazel M; Ottenhoff, Tom H M
Intracellular cytokine staining combined with flow cytometry is one of a number of assays designed to assess T-cell immune responses. It has the specific advantage of enabling the simultaneous assessment of multiple phenotypic, differentiation and functional parameters pertaining to responding T-cells, most notably, the expression of multiple effector cytokines. These attributes make the technique particularly suitable for the assessment of T-cell immune responses induced by novel tuberculosis vaccines in clinical trials. However, depending upon the particular nature of a given vaccine and trial setting, there are approaches that may be taken at different stages of the assay that are more suitable than other alternatives. In this paper, the Tuberculosis Vaccine Initiative (TBVI) TB Biomarker Working group reports on efforts to assess the conditions that will determine when particular assay approaches should be employed. We have found that choices relating to the use of fresh whole blood or peripheral blood mononuclear cells (PBMC) and frozen PBMC; use of serum-containing or serum-free medium; length of stimulation period and use of co-stimulatory antibodies can all affect the sensitivity of intracellular cytokine assays. In the case of sample material, frozen PBMC, despite some loss of sensitivity, may be more advantageous for batch analysis. We also recommend that for multi-site studies, common antibody panels, gating strategies and analysis approaches should be employed for better comparability.
Lewis, Cindi A.; Dewhurst, Stephen; McMahon, James M.; Bunce, Catherine A.; Keefer, Michael C.; Alio, Amina P.
The informed consent (IC) process for HIV vaccine trials poses unique challenges and would benefit from improvements to its historically-based structure and format. Here, we propose a theoretical framework that provides a basis for systematically evaluating and addressing these challenges. The proposed framework follows a linear pathway, starting with the precondition of voluntariness, three main variables of valid decision-making (competency, provision of information and understanding) and then the consequential outcome of either refusal or consent to participate. The existing literature reveals that culturally appropriate provision of information and resultant understanding by the vaccine trial participant are among the most significant factors influencing the authenticity of valid decision-making, though they may be overridden by other considerations, such as individual altruism, mistrust and HIV-related stigma. Community collaborations to foster bidirectional transmission of information and more culturally tailored consenting materials therefore represent a key opportunity to enhance the informed consent process. By providing a visual synopsis of the issues most critical to IC effectiveness in a categorical and relational manner, the framework provided here presents HIV vaccine researchers a tool by which the informed consent process can be more systematically evaluated and consequently improved. PMID:24865892
... vaccinated? For many years, a set of annual vaccinations was considered normal and necessary for dogs and ... to protect for a full year. Consequently, one vaccination schedule will not work well for all pets. ...
Delrieu, Isabelle; Leboulleux, Didier; Ivinson, Karen; Gessner, Bradford D
Vaccines interrupting Plasmodium falciparum malaria transmission targeting sexual, sporogonic, or mosquito-stage antigens (SSM-VIMT) are currently under development to reduce malaria transmission. An international group of malaria experts was established to evaluate the feasibility and optimal design of a Phase III cluster randomized trial (CRT) that could support regulatory review and approval of an SSM-VIMT. The consensus design is a CRT with a sentinel population randomly selected from defined inner and buffer zones in each cluster, a cluster size sufficient to assess true vaccine efficacy in the inner zone, and inclusion of ongoing assessment of vaccine impact stratified by distance of residence from the cluster edge. Trials should be conducted first in areas of moderate transmission, where SSM-VIMT impact should be greatest. Sample size estimates suggest that such a trial is feasible, and within the range of previously supported trials of malaria interventions, although substantial issues to implementation exist.
Yang, H. H.; Wu, C. G.; Xie, G. Z.; Gu, Q. W.; Wang, B. R.; Wang, L. Y.; Wang, H. F.; Ding, Z. S.; Yang, Y.; Tan, W. S.; Wang, W. Y.; Wang, X. C.; Qin, M.; Wang, J. H.; Tang, H. A.; Jiang, X. M.; Li, Y. H.; Wang, M. L.; Zhang, S. L.; Li, G. L.
OBJECTIVE: To test the efficacy of locally produced Vi vaccine over a time period of longer than one year. METHODS: A double-blinded, randomized field trial was performed in Guangxi Zhuang Autonomous Region in south-western China, using 30 micrograms doses of locally produced Vi. Enrolled subjects were 3-50 years of age, although the majority (92%) were school-aged children, who have the highest rate of typhoid fever in this setting. A total of 131,271 people were systematically allocated a single dose of 30 micrograms of Vi polysaccharide or saline placebo. The study population was followed for 19 months, with passive surveillance conducted in the Ministry of Health and the Regional Health and Anti-epidemic Centre (HAEC). Clinically suspected cases of typhoid fever were confirmed by blood culture, or by serological reaction with O-antigen (Widal tests). FINDINGS: After 19 months, there were 23 culture-confirmed cases of typhoid fever in the placebo group versus 7 cases in the Vi group (Protective efficacy (PE) = 69%; 95% CI = 28%, 87%). Most of the isolates were from school-aged children: 22 cases in the placebo group versus 6 in the Vi group (PE = 72%; 95% CI = 32%, 82%). No serious post-injection reactions were observed. The locally produced Vi polysaccharide vaccine showed levels of protective efficacy similar to those for Vi vaccine produced in industrial countries. CONCLUSION: The slightly higher dose of vaccine did not seem to alter efficacy significantly in China. PMID:11477965
Weingarten, S; Staniloff, H; Ault, M; Miles, P; Bamberger, M; Meyer, R D
Although current guidelines target hospital employees who contact high-risk patients as a high priority for influenza immunization, there are few data to support or refute this recommendation. Therefore, the authors enrolled 179 hospital employees in a randomized double-blind placebo-controlled clinical trial during the 1985-1986 influenza season. Influenza immunization was performed without serious adverse reactions and there was no increase in absenteeism attributable to the vaccination. Among those who developed clinical influenza, there was a trend toward fewer days of illness in the vaccinated group compared with the placebo group (6.0 vs. 8.0, p = 0.07). There were no statistically significant differences between subjects receiving influenza vaccine and those receiving the placebo when comparing incidences of influenza-like illness, severities of illness, and sick absenteeism. Influenza immunization of hospital employees was performed at minimal cost and risk but provided little benefit, most likely because of an unexpected drift of the prevalent influenza strain away from the vaccine type.
Koblin, Beryl A.; Bonner, Sebastian; Hoover, Donald R.; Xu, Guozhen; Lucy, Debbie; Fortin, Princess; Putnam, Sara; Latka, Mary H.
Background Limited data are available on interventions to reduce sexual risk behaviors and increase knowledge of HIV vaccine trial concepts in high risk populations eligible to participate in HIV vaccine efficacy trials. Methods The UNITY Study was a two-arm randomized trial to determine the efficacy of enhanced HIV risk reduction and vaccine trial education interventions to reduce the occurrence of unprotected vaginal sex acts and increase HIV vaccine trial knowledge among 311 HIV-negative non-injection drug using women. The enhanced vaccine education intervention using pictures along with application vignettes and enhanced risk reduction counseling consisting of three one-on-one counseling sessions were compared to standard conditions. Follow-up visits at one week and one, six and twelve months after randomization included HIV testing and assessment of outcomes. Results During follow up, the percent of women reporting sexual risk behaviors declined significantly, but did not differ significantly by study arm. Knowledge of HIV vaccine trial concepts significantly increased but did not significantly differ by study arm. Concepts about HIV vaccine trials not adequately addressed by either condition included those related to testing a vaccine for both efficacy and safety, guarantees about participation in future vaccine trials, assurances of safety, medical care, and assumptions about any protective effect of a test vaccine. Conclusions Further research is needed to boost educational efforts and strengthen risk reduction counseling among high-risk non-injection drug using women. PMID:20190585
Background Diphtheria-tetanus-whole-cell pertussis (DTPw)-based combination vaccines are an attractive option to rapidly achieve high coverage and protection against other important pathogens, such as hepatitis B virus (HBV) and Haemophilus influenzae type B (Hib). To ensure adequate antigen supply, GlaxoSmithKline Biologicals has introduced a new DTPw antigen source and developed a new DTPw-HBV/Hib combination vaccine containing a reduced amount of Hib polyribosylribitol phosphate (PRP). This study was undertaken to compare the immunogenicity and reactogenicity of this new DTPw-HBV/Hib vaccine with a licensed DTPw-HBV/Hib vaccine (Tritanrix™-HBV/Hib). Methods This was a randomized, partially-blind, multicenter study in three countries in Latin America (Argentina, Chile and Nicaragua). Healthy children received either the new DTPw-HBV/Hib vaccine (1 of 3 lots; n = 439; double-blind) or Tritanrix™-HBV/Hib (n = 146; single-blind) co-administered with oral poliovirus vaccine (OPV) at 2, 4 and 6 months, with a booster dose at 18-24 months. Results One month after the end of the 3-dose primary vaccination course, the new DTPw-HBV/Hib vaccine was non-inferior to Tritanrix™-HBV/Hib in terms of seroprotection/vaccine response rates for all component antigens; ≥97.3% and ≥93.9% of subjects in the two groups, respectively, had seroprotective levels of antibodies against diphtheria, tetanus, hepatitis B and Hib and a vaccine response to the pertussis component. Persistence of antibodies against all vaccine antigens was comparable between groups, with marked increases in all antibody concentrations after booster administration in both groups. Both vaccines were generally well-tolerated as primary and booster doses. Conclusions Results confirm the suitability of this new DTPw-HBV/Hib vaccine comprising antigens from a new source and a reduced PRP content for inclusion into routine childhood vaccination programs. Trial registration http://www.clinicaltrials.gov NCT
Zhang, Zhaoyang; Fang, Hua; Wang, Honggang
Web-delivered clinical trials generate big complex data. To help untangle the heterogeneity of treatment effects, unsupervised learning methods have been widely applied. However, identifying valid patterns is a priority but challenging issue for these methods. This paper, built upon our previous research on multiple imputation (MI)-based fuzzy clustering and validation, proposes a new MI-based Visualization-aided validation index (MIVOOS) to determine the optimal number of clusters for big incomplete longitudinal Web-trial data with inflated zeros. Different from a recently developed fuzzy clustering validation index, MIVOOS uses a more suitable overlap and separation measures for Web-trial data but does not depend on the choice of fuzzifiers as the widely used Xie and Beni (XB) index. Through optimizing the view angles of 3-D projections using Sammon mapping, the optimal 2-D projection-guided MIVOOS is obtained to better visualize and verify the patterns in conjunction with trajectory patterns. Compared with XB and VOS, our newly proposed MIVOOS shows its robustness in validating big Web-trial data under different missing data mechanisms using real and simulated Web-trial data.
Moodie, Zoe; Metch, Barbara; Bekker, Linda-Gail; Churchyard, Gavin; Nchabeleng, Maphoshane; Mlisana, Koleka; Laher, Fatima; Roux, Surita; Mngadi, Kathryn; Innes, Craig; Mathebula, Matsontso; Allen, Mary; Bentley, Carter; Gilbert, Peter B.; Robertson, Michael; Kublin, James; Corey, Lawrence; Gray, Glenda E.
Background The Phase 2b double-blinded, randomized Phambili/HVTN 503 trial evaluated safety and efficacy of the MRK Ad5 gag/pol/nef subtype B HIV-1 preventive vaccine vs placebo in sexually active HIV-1 seronegative participants in South Africa. Enrollment and vaccinations stopped and participants were unblinded but continued follow-up when the Step study evaluating the same vaccine in the Americas, Caribbean, and Australia was unblinded for non-efficacy. Final Phambili analyses found more HIV-1 infections amongst vaccine than placebo recipients, impelling the HVTN 503-S recall study. Methods HVTN 503-S sought to enroll all 695 HIV-1 uninfected Phambili participants, provide HIV testing, risk reduction counseling, physical examination, risk behavior assessment and treatment assignment recall. After adding HVTN 503-S data, HIV-1 infection hazard ratios (HR vaccine vs. placebo) were estimated by Cox models. Results Of the 695 eligible, 465 (67%) enrolled with 230 from the vaccine group and 235 from the placebo group. 38% of the 184 Phambili dropouts were enrolled. Enrollment did not differ by treatment group, gender, or baseline HSV-2. With the additional 1286 person years of 503-S follow-up, the estimated HR over Phambili and HVTN 503-S follow-up was 1.52 (95% CI 1.08–2.15, p = 0.02, 82 vaccine/54 placebo infections). The HR was significant for men (HR = 2.75, 95% CI 1.49, 5.06, p = 0.001) but not for women (HR = 1.12, 95% CI 0.73, 1.72, p = 0.62). Conclusion The additional follow-up from HVTN 503-S supported the Phambili finding of increased HIV-1 acquisition among vaccinated men and strengthened the evidence of lack of vaccine effect among women. Trial Registration clinicaltrials.gov NCT00413725 SA National Health Research Database DOH-27-0207-1539 PMID:26368824
Netterlid, Eva; Månsson, Marie Edwinson; Håkansson, Anders
One way to maintain confidence in vaccination programmes is to improve monitoring of immunisation safety. We studied active parental reporting of adverse events after a booster dose of diphtheria-tetanus toxoid (DT). 7193 children received the vaccine. Questionnaires were submitted by 84.2% of the parents, who reported reactions for 9.2% of the children. Four percent of events were classified as moderate/severe by interviews. Relative risk of redness and swelling reported was 0.24 (95% CI, 0.13-0.42) compared to a clinical trial, while it was 71.0 (44-114) compared to passive surveillance. Active surveillance by parental reports is a useful complement to passive surveillance of childhood immunisations to generate hypotheses for evaluation in controlled studies.
Mosley, Wiley H.; McCormack, William M.; Fahimuddin, M.; Aziz, K. M. A.; Rahman, A. S. M. Mizanur; Chowdhury, A. K. M. Alauddin; Martin, Albert R.; Feeley, John C.; Phillips, Robert A.
A controlled cholera vaccine field trial was carried out in rural East Pakistan during the 1966-67 cholera season. A commercial cholera vaccine of average potency was tested in 40 000 children aged 3 months to 14 years in 1- and 2-dose schedules. In the cholera season extending for 8 months following immunization, a single dose produced an over-all protection of 46%; 2 doses at an interval of 1 month provided 64% protection. The single dose was virtually ineffective in children under 5 years, but provided significant protection in older children. The enhanced effect of the 2-dose schedule was primarily due to the boosting of protection in children under the age of 5 years. The duration of significant protection, even with the 2-dose schedule, did not appear to extend beyond the first 3 months of the 8-month cholera season. PMID:5306538
Dunning, Andrew J; DiazGranados, Carlos A; Voloshen, Timothy; Hu, Branda; Landolfi, Victoria A; Talbot, H Keipp
Although a number of studies have investigated and quantified immune correlates of protection against influenza in adults and children, data on immune protection in the elderly are sparse. A recent vaccine efficacy trial comparing standard-dose with high-dose inactivated influenza vaccine in persons 65 years of age and older provided the opportunity to examine the relationship between values of three immunologic assays and protection against community-acquired A/H3N2 influenza illness. The high-dose vaccine induced significantly higher antibody titers than the standard-dose vaccine for all assays. For the hemagglutination inhibition assay, a titer of 40 was found to correspond with 50% protection when the assay virus was antigenically well matched to the circulating virus--the same titer as is generally recognized for 50% protection in younger adults. A dramatically higher titer was required for 50% protection when the assay virus was a poor match to the circulating virus. With the well-matched virus, some protection was seen at the lowest titers; with the poorly matched virus, high levels of protection were not achieved even at the highest titers. Strong associations were also seen between virus neutralization test titers and protection, but reliable estimates for 50% protection were not obtained. An association was seen between titers of an enzyme-linked lectin assay for antineuraminidase N2 antibodies and protection; in particular, the proportion of treatment effect explained by assay titer in models that included both this assay and one of the other assays was consistently higher than in models that included either assay alone. (This study has been registered at ClinicalTrials.gov under registration no. NCT01427309.).
Turriziani, Mario; Fantini, Massimo; Benvenuto, Monica; Izzi, Valerio; Masuelli, Laura; Sacchetti, Pamela; Modesti, Andrea; Bei, Roberto
Carcinoembryonic antigen (CEA), a glycosylated protein of MW 180 kDa, is overexpressed in a wide range of human carcinomas, including colorectal, gastric, pancreatic, non-small cell lung and breast carcinomas. Accordingly, CEA is one of several oncofetal antigens that may serve as a target for active anti-cancer specific immunotherapy. Experimental results obtained by employing animal models have supported the design of clinical trials using a CEA-based vaccine for the treatment of different types of human cancers. This review reports findings from experimental models and clinical evidence on the use of a CEA-based vaccine for the treatment of cancer patients. Among the diverse CEA-based cancer vaccines, DCs- and recombinant viruses-based vaccines seem the most valid. However, although vaccination was shown to induce a strong immune response to CEA, resulting in a delay in tumor progression and prolonged survival in some cancer patients, it failed to eradicate the tumor in most cases, owing partly to the negative effect exerted by the tumor microenvironment on immune response. Thus, in order to develop more efficient and effective cancer vaccines, it is necessary to design new clinical trials combining cancer vaccines with chemotherapy, radiotherapy and drugs which target those factors responsible for immunosuppression of immune cells. This review also discusses relevant patents relating to the use of CEA as a cancer vaccine.
Szu, Shousun C.; Lin, Kimi F-Y; Hunt, Steven; Chu, Chiayung; Thinh, Nguyen Duc
Background Typhoid fever remains an important cause of morbidity and mortality in the developing countries. Vi capsular polysaccharide conjugate vaccine demonstrated safety and efficacy in young children in high endemic regions. A novel typhoid conjugate vaccine based on plant polysaccharide pectin was studied in a phase I trial. Methods Fruit pectin, having the same carbohydrate backbone structure as Vi, was purified from citrus peel and used as the polysaccharide source to prepare a semi-synthetic typhoid conjugate vaccine. Pectin was chemically O-acetylated (OAcPec) to antigenically resemble Vi and conjugated to carrier protein rEPA, a recombinant exoprotein A from Pseudomonas aeruginosa. 25 healthy volunteers, 18–45 years old, were injected once with OAcPec-rEPA. Safety and IgG antibodies reactive with Vi and pectin were analyzed. Results No vaccine associated serious adverse reaction was reported. Six weeks after the injection of OAcPec-rEPA, 64% of the volunteers elicited >4 fold rise of anti-Vi IgG. At 26 weeks the level declined, but the difference between the levels at 6 and 26 weeks are not statistically significant. There is a direct correlation between the level of anti-Vi IgG before and after the injection (R2 = 0.96). The anti-Vi IgG can be absorbed by Vi, but not by pectin. There was no corresponding increase of anti-pectin after the injection, indicating the antibody response to OAcPec-rEPA was specific to Vi. There is no Vi-rEPA data in US adults for comparison of immune responses. The OAcPec-rEPA elicited significantly less IgG anti-Vi in US adults than those by Vi-rEPA in Vietnamese adults. Conclusion The O-acetylated pectin conjugate, a plant based typhoid vaccine, is safe and immunogenic in adult volunteers. PMID:24657719
... page: //medlineplus.gov/ency/article/000594.htm HIV/AIDS To use the sharing features on this page, ... immunodeficiency virus (HIV) is the virus that causes AIDS. When a person becomes infected with HIV, the ...
Fuchs, Jonathan D.; Sobieszczyk, Magdalena E.; Madenwald, Tamra; Grove, Doug; Karuna, Shelly T.; Andrasik, Michele; Sherwat, Adam; Broder, Gail; Mayer, Kenneth; Koblin, Beryl; Hammer, Scott
In November 2010, the iPrEx study reported that pre-exposure prophylaxis (PrEP) with daily tenofovir disoproxil fumarate/emtricitabine reduced HIV infections by 44% among men who have sex with men and subsequent trials corroborated efficacy among heterosexual men and women. During regularly scheduled follow-up visits from January-March 2011, participants in an ongoing phase 2b vaccine efficacy trial completed an anonymous web survey about PrEP. Among 376 respondents, 17% reported they were very likely to use PrEP in the next year. Non-white participants were more likely to use PrEP. Among those with some level of interest, intent to use PrEP was greatest if the drug were available through the clinical trial or health insurance. Most (91%) believed taking PrEP would not change their willingness to stay in the vaccine trial and few thought it would affect recruitment. As key stakeholders, currently enrolled trial participants can offer vital input about emerging prevention technologies that may affect the design of future HIV vaccine and non-vaccine prevention trials. PMID:23614998
When HIV was discovered and established as the cause of AIDS in 1983–1984, many people believed that a vaccine would be rapidly developed. However, 30 years have passed and we are still struggling to develop an elusive vaccine. In trying to achieve that goal, different scientific paradigms have been explored. Although major progress has been made in understanding the scientific basis for HIV vaccine development, efficacy trials have been critical in moving the field forward. Major lessons learned are: the development of an HIV vaccine is an extremely difficult challenge; the temptation of just following the fashion should be avoided; clinical trials are critical, especially large-scale efficacy trials; HIV vaccine research will require long-term commitment; and sustainable collaborations are needed to accelerate the development of an HIV vaccine. Concrete actions must be implemented with the sense of urgency imposed by the severity of the AIDS epidemic. PMID:26344345
Vaughan, Jefferson A.; Scheller, Libia F.; Wirtz, Robert A.; Azad, Abdu F.
Plasmodium berghei sporozoites delivered by mosquito bite were more infectious to outbred CD-1 mice than were sporozoites delivered by intravenous inoculation. The route of challenge also affected vaccine efficacy. In view of these findings and the fact that mosquito bites are the natural mode of sporozoite delivery, infectious mosquito bites should be considered the challenge protocol of choice for sporozoite vaccine efficacy trials. PMID:10417207
Schouten, Jeffrey T.; Dixon, Dennis; Varghese, Suresh; Cope, Marie T.; Marci, Joe; Kagan, Jonathan M.
Background Identifying efficacious interventions for the prevention and treatment of human diseases depends on the efficient development and implementation of controlled clinical trials. Essential to reducing the time and burden of completing the clinical trial lifecycle is determining which aspects take the longest, delay other stages, and may lead to better resource utilization without diminishing scientific quality, safety, or the protection of human subjects. Purpose In this study we modeled time-to-event data to explore relationships between clinical trial protocol development and implementation times, as well as identify potential correlates of prolonged development and implementation. Methods We obtained time interval and participant accrual data from 111 interventional clinical trials initiated between 2006 and 2011 by NIH’s HIV/AIDS Clinical Trials Networks. We determined the time (in days) required to complete defined phases of clinical trial protocol development and implementation. Kaplan-Meier estimates were used to assess the rates at which protocols reached specified terminal events, stratified by study purpose (therapeutic, prevention) and phase group (pilot/phase I, phase II, and phase III/ IV). We also examined several potential correlates to prolonged development and implementation intervals. Results Even though phase grouping did not determine development or implementation times of either therapeutic or prevention studies, overall we observed wide variation in protocol development times. Moreover, we detected a trend toward phase III/IV therapeutic protocols exhibiting longer developmental (median 2 ½ years) and implementation times (>3years). We also found that protocols exceeding the median number of days for completing the development interval had significantly longer implementation. Limitations The use of a relatively small set of protocols may have limited our ability to detect differences across phase groupings. Some timing effects
Young, April M; Stephens, Dustin B; Khaleel, Hanan A; Havens, Jennifer R
Candidate prophylactic HCV vaccines are approaching phase III clinical trial readiness, yet little is known about the potential for participation among target groups or innovative ways to promote enrollment within 'hard-to-reach' populations. This study describes HCV vaccine trial participation willingness among a high-risk sample of people who use drugs and their willingness to assist researchers by promoting the trial among peers. Willingness to participate in and encourage peers' participation in an HCV vaccine trial was assessed among injection and non-injection drug users enrolled in a cohort study in Kentucky using interviewer-administered questionnaires (n=165 and 415, respectively, with willingness to participate assessed among HCV-seronegative participants only). Generalized linear mixed models were used to determine correlates to being "very likely" to participate or encourage participation in a trial. Most reported being likely to participate or encourage participation in a vaccine trial (63% and 87%, respectively). Men were significantly less likely to report willingness to encourage others' participation, while willingness to encourage was higher among lower income, HCV-seropositive, heroin-using, and methamphetamine-using participants. Unemployment, lesser education, receipt of financial support from more peers, and nonmedical prescription drug use were positively associated with willingness to participate. Differential enrollment in HCV vaccine clinical trials by socioeconomic status may occur, underscoring ethical considerations and need for avoiding coercion. Notably, the data suggest that a peer-driven approach to promoting trial participation among people who use drugs could be feasible in this population and that HCV-seropositive individuals and women could be especially instrumental in these efforts.
Gadzinowski, Janusz; Albrecht, Piotr; Hasiec, Barbara; Konior, Ryszard; Dziduch, Jerzy; Witor, Anita; Mellelieu, Tracey; Tansey, Susan P; Jones, Thomas; Sarkozy, Denise; Emini, Emilio A; Gruber, William C; Scott, Daniel A
13-valent pneumococcal conjugate vaccine (PCV13) includes polysaccharide conjugates from six pneumococcal serotypes in addition to those in the licensed 7-valent vaccine, thereby offering expanded protection against pneumococcal disease. The phase 3 trial reported here was conducted per a regulatory requirement to evaluate the immunogenicity, safety, and tolerability of two lots of the final PCV13 formulation that differed with respect to production scale but not the manufacturing process. The anti-pneumococcal polysaccharide immunogenicity and safety/tolerability were found to be similar between the two PCV13 vaccine lots.
Enwere, Godwin C.; Paranjape, Gandhali; Kulkarni, Prasad S.; Ginde, Manisha; Hartmann, Katharina; Viviani, Simonetta; Chaumont, Julie; Martellet, Lionel; Makadi, Marie-Francoise; Ivinson, Karen; Marchetti, Elisa; Herve, Jacques; Kertson, Kim; LaForce, F. Marc; Preziosi, Marie-Pierre
Background. The determination of the safety profile of any vaccine is critical to its widespread use in any population. In addition, the application of international guidelines to fit local context could be a challenging but important step toward obtaining quality safety data. Methods. In clinical studies of PsA-TT (MenAfriVac), safety was monitored immediately after vaccination, at 4–7 days for postimmunization local and systemic reactions, within 28 days for adverse events, and throughout the duration of study for serious adverse events. Initial and ongoing training of sites' staff were undertaken during the studies, and a data and safety monitoring board reviewed all the data during and after the studies. Results. The safety of PsA-TT was evaluated according to international standards despite obvious challenges in remote areas where these studies were conducted. These challenges included the need for uniformity of methods, timely reporting in the context of frequent communication problems, occurrence of seasonal diseases such as malaria and rotavirus diarrhea, and healthcare systems that required improvement. Conclusions. The trials of PsA-TT highlighted the value of a robust vaccine development plan and design so that lessons learned in initial studies were incorporated into the subsequent ones, initial training and periodic retraining, strict monitoring of all procedures, and continuous channel of communication with all stakeholders that enabled the application of international requirements to local settings, with high quality of data. PMID:26553681
Shreif, Z.; Adhangale, P.; Cheluvaraja, S.; Perera, R.; Kuhn, R.; Ortoleva, P.
Enveloped viruses are viewed as an opportunity to understand how highly organized and functional biosystems can emerge from a collection of millions of chaotically moving atoms. They are an intermediate level of complexity between macromolecules and bacteria. They are a natural system for testing theories of self-assembly and structural transitions, and for demonstrating the derivation of principles of microbiology from laws of molecular physics. As some constitute threats to human health, a computer-aided vaccine and drug design strategy that would follow from a quantitative model would be an important contribution. However, current molecular dynamics simulation approaches are not practical for modeling such systems. Our multiscale approach simultaneously accounts for the outer protein net and inner protein/genomic core, and their less structured membranous material and host fluid. It follows from a rigorous multiscale deductive analysis of laws of molecular physics. Two types of order parameters are introduced: (1) those for structures wherein constituent molecules retain long-lived connectivity (they specify the nanoscale structure as a deformation from a reference configuration) and (2) those for which there is no connectivity but organization is maintained on the average (they are field variables such as mass density or measures of preferred orientation). Rigorous multiscale techniques are used to derive equations for the order parameters dynamics. The equations account for thermal-average forces, diffusion coefficients, and effects of random forces. Statistical properties of the atomic-scale fluctuations and the order parameters are co-evolved. By combining rigorous multiscale techniques and modern supercomputing, systems of extreme complexity can be modeled.
Shreif, Z.; Adhangale, P.; Cheluvaraja, S.; Perera, R.; Kuhn, R.; Ortoleva, P.
Enveloped viruses are viewed as an opportunity to understand how highly organized and functional biosystems can emerge from a collection of millions of chaotically moving atoms. They are an intermediate level of complexity between macromolecules and bacteria. They are a natural system for testing theories of self-assembly and structural transitions, and for demonstrating the derivation of principles of microbiology from laws of molecular physics. As some constitute threats to human health, a computer-aided vaccine and drug design strategy that would follow from a quantitative model would be an important contribution. However, current molecular dynamics simulation approaches are not practical for modeling such systems. Our multiscale approach simultaneously accounts for the outer protein net and inner protein/genomic core, and their less structured membranous material and host fluid. It follows from a rigorous multiscale deductive analysis of laws of molecular physics. Two types of order parameters are introduced: (1) those for structures wherein constituent molecules retain long-lived connectivity (they specify the nanoscale structure as a deformation from a reference configuration) and (2) those for which there is no connectivity but organization is maintained on the average (they are field variables such as mass density or measures of preferred orientation). Rigorous multiscale techniques are used to derive equations for the order parameters dynamics. The equations account for thermal-average forces, diffusion coefficients, and effects of random forces. Statistical properties of the atomic-scale fluctuations and the order parameters are co-evolved. By combining rigorous multiscale techniques and modern supercomputing, systems of extreme complexity can be modeled.
Urbani, Francesca; Proietti, Enrico
The development of immune monitoring assays is essential to determine the immune responses against tumor-specific antigens (TSAs) and tumor-associated antigens (TAAs) and their possible correlation with clinical outcome in cancer patients receiving immunotherapies. Despite the wide range of techniques used, to date these assays have not shown consistent results among clinical trials and failed to define surrogate markers of clinical efficacy to antitumor vaccines. Multiparameter flow cytometry- (FCM-) based assays combining different phenotypic and functional markers have been developed in the past decade for informative and longitudinal analysis of polyfunctional T-cells. These technologies were designed to address the complexity and functional heterogeneity of cancer biology and cellular immunity and to define biomarkers predicting clinical response to anticancer treatment. So far, there is still a lack of standardization of some of these immunological tests. The aim of this review is to overview the latest technologies for immune monitoring and to highlight critical steps involved in some of the FCM-based cellular immune assays. In particular, our laboratory is focused on melanoma vaccine research and thus our main goal was the validation of a functional multiparameter test (FMT) combining different functional and lineage markers to be applied in clinical trials involving patients with melanoma. PMID:24195078
Martin, David J.; Chernoff, Robert A.; Buitron, Michael; Comulada, W. Scott; Liang, Li-Jung; Wong, F. Lennie
Objective New treatments introduced in the mid 1990s led many people with HIV/AIDS who previously had been disabled by their disease to contemplate workforce reentry; many remain unemployed, and little is known concerning interventions that might help them return to work. We report the results of a randomized clinical trial (RCT) of an intervention designed to help people with HIV/AIDS reenter the workforce. Design We tested a mixed (group – individual) modality intervention that incorporated elements of Motivational Interviewing (Miller & Rollnick, 2002), skills building from Dialectical Behavior Therapy (Linehan, 1993), and job-related skills (Price & Vinokur, 1995). A total of 174 individuals participated in either the intervention or in standard of care and were followed for 24 months. Results Compared to individuals referred for standard of care, participants in the intervention engaged in more workforce-reentry activities over time and, once employed, were more likely to remain employed. Dose-response analyses revealed that among intervention participants, participants who attended more than one individual session engaged in more workforce-reentry activities than did individual who attended one or fewer individual sessions, whereas frequency of group session participation did not effect a difference between participants who attended more than six group sessions and participants who attended six or fewer group sessions. Conclusion Theoretically-based workforce-reentry assistance programs can assist disabled people with HIV/AIDS in their return-to-work efforts. PMID:23148715
Stensballe, Lone Graff; Sørup, Signe; Aaby, Peter; Benn, Christine Stabell; Greisen, Gorm; Jeppesen, Dorthe Lisbeth; Birk, Nina Marie; Kjærgaard, Jesper; Nissen, Thomas Nørrelykke; Pihl, Gitte Thybo; Thøstesen, Lisbeth Marianne; Kofoed, Poul-Erik; Pryds, Ole; Ravn, Henrik
Background The BCG vaccine is administered to protect against tuberculosis, but studies suggest there may also be non-specific beneficial effects upon the infant immune system, reducing early non-targeted infections and atopic diseases. The present randomised trial tested the hypothesis that BCG vaccination at birth would reduce early childhood hospitalisation in Denmark, a high-income setting. Methods Pregnant women planning to give birth at three Danish hospitals were invited to participate. After parental consent, newborn children were allocated to BCG or no intervention within 7 days of age. Randomisation was stratified by prematurity. The primary study outcome was number of all-cause hospitalisations analysed as repeated events. Hospitalisations were identified using The Danish National Patient Register. Data were analysed by Cox proportional hazards models in intention-to-treat and per-protocol analyses. Results 4184 pregnant women were randomised and their 4262 children allocated to BCG or no intervention. There was no difference in risk of hospitalisation up to 15 months of age; 2129 children randomised to BCG experienced 1047 hospitalisations with a mean of 0.49 hospitalisation per child compared with 1003 hospitalisations among 2133 control children (mean 0.47), resulting in a HR comparing BCG versus no BCG of 1.05 (95% CI 0.93 to 1.18) (intention-to-treat analysis). The effect of BCG was the same in children born at term (1.05 (0.92 to 1.18)) and prematurely (1.07 (0.63 to 1.81), p=0.94). The effect was also similar in the two sexes and across study sites. The results were essentially identical in the per-protocol analysis and after adjustment for baseline characteristics. Conclusions BCG vaccination at birth did not reduce the risk of hospitalisation for somatic acquired disease until 15 months of age in this Danish study population. Trial registration number NCT01694108, results. PMID:27443836
Brill, Thomas H; Kübler, Hubert R; Pohla, Heike; Buchner, Alexander; Fend, Falko; Schuster, Tibor; van Randenborgh, Heiner; Paul, Roger; Kummer, Tania; Plank, Christian; Eisele, Bernd; Breul, Jürgen; Hartung, Rudolf; Schendel, Dolores J; Gansbacher, Bernd
Immunotherapy with whole cell cancer vaccines has been tested in various tumor types. This study investigated the safety profile and antitumor activity of an allogeneic prostate carcinoma cell line, LNCaP, expressing recombinant human interleukin-2 and human interferon-gamma. Thirty HLA-A*0201-matched patients with progressive, castration-resistant prostate cancer received four intradermal injections on days 1, 15, 29, and 92, and then every 90 days, as long as no tumor progression occurred. Three patients received a dose level of 7.5 million cells, and 27 patients received 15 million cells per injection. The primary study criteria were safety and the difference in prostate-specific antigen doubling time (PSA-DT), determined in the pretreatment phase (before the start of vaccination) and in the trial treatment phase (during vaccination). No dose-limiting or autoimmune toxicity was seen. During vaccination there was a significant prolongation of the PSA-DT compared with the prevaccination period (prolongation from 63 to 114 days; p < 0.01; intention to treat). In addition, results showed a period of PSA stabilization of at least 12 weeks, together with stable bone scans in 12 of 30 patients, and 3 patients sustained a >50% decrease in PSA versus baseline. The median overall survival time from first vaccination was 32 months (mean value, 34 months). Immune monitoring revealed T cell stimulation in the majority of patients. This vaccine strategy was found to be safe and well tolerated and was accompanied by prolongation of PSA-DT. The results of this trial warrant clinical development of this vaccine.
Scheinberg DA. Vaccination with Synthetic Analog Peptides Derived from WT1 Oncoprotein Induces T Cell Responses in Patients with Complete Remission ...TITLE:Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural Mesothelioma after Completion of...TITLE:Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural Mesothelioma after Completion of Multimodality
Kreimer, Aimée R.; Gonzalèz, Paula; Katki, Hormuzd A.; Porras, Carolina; Schiffman, Mark; Rodriguez, Ana Cecilia; Solomon, Diane; Jimenez, Silvia; Schiller, John T.; Lowy, Douglas R.; van Doorn, Leen-Jan; Struijk, Linda; Quint, Wim; Chen, Sabrina; Wacholder, Sholom; Hildesheim, Allan; Herrero, Rolando
Background Anal cancer remains rare (incidence of ∼1.5 per 100,000 women annually) but rates are increasing in many countries. Human papillomavirus-16 (HPV16) infection causes most cases. We evaluated vaccine efficacy (VE) of an ASO4-adjuvanted HPV16/18 vaccine against anal HPV16/18 infection. Methods In a randomized double-blind controlled trial designed to evaluate VE against persistent cervical HPV16/18 infections and associated precancerous lesions in Costa Rica, 4210 healthy women underwent anal specimen collection (4224 of 5968= 70.8% of eligible women) at the final blinded study visit 4 years after vaccination to evaluate anal HPV16/18 VE. Cervical HPV16/18 VE among the same women at the same visit was calculated as a comparator. For this ancillary work, analyses were conducted in a restricted cohort of women both cervical HPV16/18 DNA negative and HPV 16/18 seronegative prior at enrollment (N=1989), and in the full cohort (all women with an anal specimen). Findings In the restricted cohort, VE against prevalent HPV16/18 anal infection measured one-time, four-years post-vaccination was 83.6% (95%CI 66.7% to 92.8%), which was comparable to cervical HPV16/18 VE (87.9%, 95%CI 77.4% to 94.0%). In the full cohort, HPV16/18 VE was statistically lower at the anus (62.0%, 95%CI 47.1% to 73.1%) compared to the cervix (76.4%, 95%CI 67.0% to 83.5%) (p for anatomic-site interaction =0.03). Significant and comparable VE estimates against a composite endpoint of HPV31/33/45 (i.e.: cross-protection) was observed at the anus and cervix. Interpretation The ASO4-adjuvanted vaccine affords strong protection against anal HPV, particularly among women more likely to be HPV naïve at vaccination. Funding. The Costa Rica HPV Vaccine Trial is sponsored and funded by the NCI (contract N01-CP-11005), with funding support from the National Institutes of Health Office of Research on Women's Health, and conducted with support from the Ministry of Health of Costa Rica. Vaccine was
Ahmad, Shamaila Munir; Abildgaard, Niels; Straten, Per Thor; Svane, Inge Marie; Andersen, Mads Hald; Knudsen, Lene Meldgaard
The B-cell lymphoma-2 (Bcl-2) family of proteins play a crucial role in multiple myeloma (MM), contributing to lacking apoptosis which is a hallmark of the disease. This makes the Bcl-2 proteins interesting targets for therapeutic peptide vaccination. We report a phase I trial of therapeutic vaccination with peptides from the proteins Bcl-2, Bcl-XL and Mcl-1 in patients with relapsed MM. Vaccines were given concomitant with bortezomib. Out of 7 enrolled patients, 4 received the full course of 8 vaccinations. The remaining 3 patients received fewer vaccinations due to progression, clinical decision of lacking effect and development of hypercalcemia, respectively. There were no signs of toxicity other than what was to be expected from bortezomib. Immune responses to the peptides were seen in all 6 patients receiving more than 2 vaccinations. Three patients had increased immune responses after vaccination. Vaccination against Bcl-2 was well tolerated and was able to induce immune responses in patients with relapsed MM. PMID:28078275
Taddio, Anna; Parikh, Chaitya; Yoon, Eugene W; Sgro, Michael; Singh, Harvinder; Habtom, Erita; Ilersich, Andrew F; Pillai Riddell, Rebecca; Shah, Vibhuti
Educating parents about ways to minimize pain during routine infant vaccine injections at the point of care may positively impact on pain management practices. The objective of this cluster randomized trial was to determine the impact of educating parents about pain in outpatient pediatric clinics on their use of pain treatments during routine infant vaccinations. Four hospital-based pediatric clinics were randomized to intervention or control groups. Parents of 2- to 4-month-old infants attending the intervention clinics reviewed a pamphlet and a video about vaccination pain management on the day of vaccination, whereas those in the control clinics did not. Parent use of specific pain treatments (breastfeeding, sugar water, topical anesthetics, and/or holding of infants) on the education day and at subsequent routine vaccinations 2 months later was the primary outcome. Altogether, 160 parent-infant dyads (80 per group) participated between November 2012 and February 2014; follow-up data were available for 126 (79%). Demographics did not differ between groups (P > 0.05). On the education day and at follow-up vaccinations, use of pain interventions during vaccinations was higher in the intervention group (80% vs 26% and 68% vs 32%, respectively; P < 0.001 for both analyses). Educating parents about pain management in a hospital outpatient setting leads to higher use of pain interventions during routine infant vaccinations.
Song, Joon Young; Cheong, Hee Jin; Lee, Jacob; Wie, Seong-Heon; Park, Kyung-Hwa; Kee, Sae Yoon; Jeong, Hye Won; Kim, Yeon-Sook; Noh, Ji Yun; Choi, Won Suk; Park, Dae Won; Sohn, Jang Wook; Kim, Woo Joo
Influenza vaccines are the primary method for preventing influenza and its complications. Considering the increasing demand for influenza vaccines, vaccine manufacturers are required to establish large-scale production systems. This phase IV randomized trial was conducted to evaluate the lot consistency of trivalent split influenza vaccines regarding immunogenicity and safety. A total of 1,023 healthy adults aged 18-64 y were enrolled in the study. Subjects were randomly assigned in a 1:1 ratio to receive the GC FLU® Prefilled Syringe or the GC FLU® Injection, and they were further randomized to one of 3 lots of each vaccine in a 1:1:1 ratio. In both GC FLU® Injection and GC FLU® Prefilled Syringe groups, immune responses were equivalent between lots for each of the 3 vaccine strains on day 21. The 2-sided 95% CI of GMT ratios between pairs of lots were between 0.67 and 1.5, meeting the equivalence criteria. After vaccination, all 3 criteria of the European Medicines Agency were met in both GC FLU® Injection and GC FLU® Prefilled Syringe groups. The vaccines showed tolerable safety profiles without serious adverse events. The demonstration of lot consistency, robust immunogenic responses and favorable safety profiles support the reliability of mass-manufacturing systems for the GC FLU® Injection and GC FLU® Prefilled Syringe.
Vaccinations are injections of antigens into the body. Once the antigens enter the blood, they circulate along ... suppressor T cells stop the attack. After a vaccination, the body will have a memory of an ...
Diakite, Ibrahim; Mooring, Eric Q.; Velásquez, Gustavo E.; Murray, Megan B.
Background During the 2014 Ebola virus disease (EVD) outbreak, policy-makers were confronted with difficult decisions on how best to test the efficacy of EVD vaccines. On one hand, many were reluctant to withhold a vaccine that might prevent a fatal disease from study participants randomized to a control arm. On the other, regulatory bodies called for rigorous placebo-controlled trials to permit direct measurement of vaccine efficacy prior to approval of the products. A stepped-wedge cluster study (SWCT) was proposed as an alternative to a more traditional randomized controlled vaccine trial to address these concerns. Here, we propose novel “ordered stepped-wedge cluster trial” (OSWCT) designs to further mitigate tradeoffs between ethical concerns, logistics, and statistical rigor. Methodology/Principal Findings We constructed a spatially structured mathematical model of the EVD outbreak in Sierra Leone. We used the output of this model to simulate and compare a series of stepped-wedge cluster vaccine studies. Our model reproduced the observed order of first case occurrence within districts of Sierra Leone. Depending on the infection risk within the trial population and the trial start dates, the statistical power to detect a vaccine efficacy of 90% varied from 14% to 32% for standard SWCT, and from 67% to 91% for OSWCTs for an alpha error of 5%. The model’s projection of first case occurrence was robust to changes in disease natural history parameters. Conclusions/Significance Ordering clusters in a step-wedge trial based on the cluster’s underlying risk of infection as predicted by a spatial model can increase the statistical power of a SWCT. In the event of another hemorrhagic fever outbreak, implementation of our proposed OSWCT designs could improve statistical power when a step-wedge study is desirable based on either ethical concerns or logistical constraints. PMID:27509037
Kreimer, Aimée R; Struyf, Frank; Del Rosario-Raymundo, Maria Rowena; Hildesheim, Allan; Skinner, S Rachel; Wacholder, Sholom; Garland, Suzanne M; Herrero, Rolando; David, Marie-Pierre; Wheeler, Cosette M
Background Limited data suggest one or two doses of the HPV vaccines confer similar protection to the three-dose regimen. This study aimed to further evaluate the question of reduced-dose efficacy of the HPV-16/18 vaccine. Methods Summary-level data from the Costa Rica Vaccine Trial (CVT; NCT00128661) and the PApilloma TRIal against Cancer In young Adults (PATRICIA; NCT001226810), two phase III controlled, randomized, double-blind, clinical trials of the HPV-16/18 AS04-adjuvanted vaccine among young women, were combined in a post-hoc analysis (GSK e-track 202142) to investigate efficacy of fewer doses of the HPV-16/18 vaccine after four years of follow-up. Women were randomly assigned to receive three doses of the HPV-16/18 vaccine or to a control vaccine; yet some received fewer doses. After excluding women with <12-months follow-up or those HPV16/18 DNA-positive at enrollment (for the HPV16/18 endpoint), vaccine efficacy (VE) was calculated against one-time detection of incident HPV infections after three (n=11,110 HPV:11,217control), two (n=611:574), and one (N=292:251) dose(s). The main aim of the study was to ascertain HPV16/18 VE in both full and naïve cohorts, as well as to explore protection conferred against non-vaccine HPV types, by number of doses received. Findings VE against incident HPV16/18 infections for three doses was 77·0% (95%CI 74·7 to 79·1%), two doses was 76·0% (95%CI 62·0 to 85·3%), and one dose was 85·7% (95%CI 70·7 to 93·7%). VE against incident HPV31/33/45 infections for three doses was 59·7% (95%CI 56·0 to 63·0%), two doses was 37·7% (95%CI 12·4 to 55·9%), and one dose was 36·6% (95%CI −5·4 to 62·2%). However, two-dose women who received their second dose at six months, but not those receiving it at one month, had efficacy estimates against HPV 31/33/45 similar to the three-dose group (VE 68·1%, 95%CI 27·0 to 87·0%; CVT data only). Interpretation Four years following vaccination of women aged 15 to 25 years, one
Zaman, K.; Fleming, Jessica A.; Victor, John C.; Yunus, Mohammad; Bari, Tajul Islam A.; Azim, Tasnim; Rahman, Mustafizur; Mowla, Syed Mohammad Niaz; Bellini, William J.; McNeal, Monica; Icenogle, Joseph P.; Lopman, Ben; Parashar, Umesh; Cortese, Margaret M.; Steele, A. Duncan; Neuzil, Kathleen M.
Background. The burden of rotavirus morbidity and mortality is high in children aged <5 years in developing countries, and evaluations indicate waning protection from rotavirus immunization in the second year. An additional dose of rotavirus vaccine may enhance the immune response and lengthen the period of protection against disease, but coadministration of this dose should not interfere with immune responses to concurrently given vaccines. Methods. A total of 480 9-month-old participants from Matlab, Bangladesh, were enrolled in a study with a primary objective to establish noninferiority of concomitant administration of measles-rubella vaccine (MR) and a third dose of human rotavirus vaccine (HRV; MR + HRV), compared with MR given alone. Secondary objectives included noninferiority of rubella antibody seroconversion and evaluating rotavirus IgA/IgG seroresponses in MR + HRV recipients. Results. Two months after vaccination, 75.3% and 74.3% of MR + HRV and MR recipients, respectively, had seroprotective levels of measles virus antibodies; 100.0% and 99.6%, respectively, showed anti–rubella virus immunoglobulin G (IgG) seroprotection. In the MR + HRV group, antirotavirus immunoglobulin A and IgG seropositivity frequencies before vaccination (52.7% and 66.3%, respectively) increased to 69.6% and 88.3% after vaccination. Conclusions. Vaccine-induced measles and rubella antibody responses are not negatively affected by concomitant administration of HRV. The HRV dose increases antirotavirus serum antibody titers and the proportion of infants with detectable antirotavirus antibody. Clinical Trials Registration. NCT01700621. PMID:26823338
Njenga, M. Kariuki; Njagi, Leonard; Thumbi, S. Mwangi; Kahariri, Samuel; Githinji, Jane; Omondi, Eunice; Baden, Amy; Murithi, Mbabu; Paweska, Janusz; Ithondeka, Peter M.; Ngeiywa, Kisa J.; Dungu, Baptiste; Donadeu, Meritxell; Munyua, Peninah M.
Background Although livestock vaccination is effective in preventing Rift Valley fever (RVF) epidemics, there are concerns about safety and effectiveness of the only commercially available RVF Smithburn vaccine. We conducted a randomized controlled field trial to evaluate the immunogenicity and safety of the new RVF Clone 13 vaccine, recently registered in South Africa. Methods In a blinded randomized controlled field trial, 404 animals (85 cattle, 168 sheep, and 151 goats) in three farms in Kenya were divided into three groups. Group A included males and non-pregnant females that were randomized and assigned to two groups; one vaccinated with RVF Clone 13 and the other given placebo. Groups B included animals in 1st half of pregnancy, and group C animals in 2nd half of pregnancy, which were also randomized and either vaccinated and given placebo. Animals were monitored for one year and virus antibodies titers assessed on days 14, 28, 56, 183 and 365. Results In vaccinated goats (N = 72), 72% developed anti-RVF virus IgM antibodies and 97% neutralizing IgG antibodies. In vaccinated sheep (N = 77), 84% developed IgM and 91% neutralizing IgG antibodies. Vaccinated cattle (N = 42) did not develop IgM antibodies but 67% developed neutralizing IgG antibodies. At day 14 post-vaccination, the odds of being seropositive for IgG in the vaccine group was 3.6 (95% CI, 1.5 – 9.2) in cattle, 90.0 (95% CI, 25.1 – 579.2) in goats, and 40.0 (95% CI, 16.5 – 110.5) in sheep. Abortion was observed in one vaccinated goat but histopathologic analysis did not indicate RVF virus infection. There was no evidence of teratogenicity in vaccinated or placebo animals. Conclusions The results suggest RVF Clone 13 vaccine is safe to use and has high (>90%) immunogenicity in sheep and goats but moderate (> 65%) immunogenicity in cattle. PMID:25756501
Fuchs, Jonathan D; Sobieszczyk, Magdalena E; Madenwald, Tamra; Grove, Doug; Karuna, Shelly T; Andrasik, Michele; Sherwat, Adam; Broder, Gail; Mayer, Kenneth; Koblin, Beryl; Hammer, Scott
In November 2010, the iPrEx study reported that preexposure prophylaxis (PrEP) with daily tenofovir disoproxil fumarate/emtricitabine reduced HIV infections by 44% among men who have sex with men and subsequent trials corroborated efficacy among heterosexual men and women. During regularly scheduled follow-up visits from January to March 2011, participants in an ongoing phase 2b vaccine efficacy trial completed an anonymous Web survey about PrEP. Among 376 respondents, 17% reported they were very likely to use PrEP in the next year. Nonwhite participants were more likely to use PrEP. Among those with some level of interest, intent to use PrEP was greatest if the drug were available through the clinical trial or health insurance. Most (91%) believed taking PrEP would not change their willingness to stay in the vaccine trial and few thought it would affect recruitment. As key stakeholders, currently enrolled trial participants can offer vital input about emerging prevention technologies that may affect the design of future HIV vaccine and nonvaccine prevention trials.
Lund, Najaaraq; Andersen, Andreas; Hansen, Anna Sofie K.; Jepsen, Frida S.; Barbosa, Amarildo; Biering-Sørensen, Sofie; Rodrigues, Amabelia; Ravn, Henrik; Aaby, Peter; Benn, Christine Stabell
Background. Routine vaccines may have nonspecific effects on mortality. An observational study found that OPV given at birth (OPV0) was associated with increased male infant mortality. We investigated the effect of OPV0 on infant mortality in a randomized trial in Guinea-Bissau. Methods. A total of 7012 healthy normal-birth-weight neonates were randomized to BCG only (intervention group) or OPV0 with BCG (usual practice). All children were to receive OPV with pentavalent vaccine (diphtheria, tetanus, pertussis, Haemophilus influenzae type b, and hepatitis B) at 6, 10, and 14 weeks of age. Seven national OPV campaigns were also conducted during the trial period. Children were followed to age 12 months. We used Cox regression to calculate hazard ratios (HRs) for mortality. Results. The trial contradicted the original hypothesis about OPV0 increasing male infant mortality. Within 12 months, 73 children in the BCG + OPV group and 87 children in the BCG-only group died, all from infectious diseases. Comparing BCG + OPV0 vs BCG only, the HR was 0.83 (95% confidence interval [CI], .61–1.13): 0.72 (95% CI, .47–1.10) in boys and 0.97 (95% CI, .61–1.54) in girls. For children enrolled within the first 2 days of life, the HR for BCG + OPV0 vs BCG only was 0.58 (95% CI, .38–.90). From enrollment until the time of OPV campaigns, the HR was 0.68 (95% CI, .45–1.00), the beneficial effect being separately significant for males (0.55 [95% CI, .32–.95]). Conclusions. This is the only randomized trial of the effect of OPV0 on mortality. OPV0 may be associated with nonspecific protection against infectious disease mortality, particularly when given early in life. There are reasons to monitor mortality when OPV is being phased out. Clinical Trials Registration. NCT00710983. PMID:26219694
Andrews, Laura; Andersen, Rikke F; Webster, Daniel; Dunachie, Susanna; Walther, R Michael; Bejon, Philip; Hunt-Cooke, Angela; Bergson, Gillian; Sanderson, Frances; Hill, Adrian V S; Gilbert, Sarah C
The demand for an effective malaria vaccine is high, with millions of people being affected by the disease every year. A large variety of potential vaccines are under investigation worldwide, and when tested in clinical trials, researchers need to extract as much data as possible from every vaccinated and control volunteer. The use of quantitative real-time polymerase chain reaction (PCR), carried out in real-time during the clinical trials of vaccines designed to act against the liver stage of the parasite's life cycle, provides more information than the gold standard method of microscopy alone and increases both safety and accuracy. PCR can detect malaria parasites in the blood up to 5 days before experienced microscopists see parasites on blood films, with a sensitivity of 20 parasites/mL blood. This PCR method has so far been used to follow 137 vaccinee and control volunteers in Phase IIa trials in Oxford and on 220 volunteer samples during a Phase IIb field trial in The Gambia.
Dotres, Carlos P; Puga, Rinaldo; Ricardo, Yariset; Broño, Carmen R; Paredes, Beatriz; Echemendía, Vladimir; Rosell, Sandra; González, Nadezhda; García-Rivera, Dagmar; Valdés, Yury; Goldblatt, David; Vérez-Bencomo, Vicente
A new heptavalent conjugate vaccine (PCV7-TT) is under development in Cuba. PCV7-TT contains 2 μg of serotypes 1, 5, 14, 18C, 19F, 23F and 4 μg of 6B, each one conjugated to tetanus toxoid (TT). This vaccine was designed with the serotypes that cause most invasive pneumococcal diseases (IPD) worldwide. In the present study, we investigated the safety and explored the immunogenicity of PCV7-TT during a controlled, randomized and double blind clinical trial phase I in 4-5-year-old children. PCV7-TT was well tolerated and as safe as Synflorix used as control vaccine. Following a single-dose vaccination, all individual serotypes included in PCV7-TT induced statistically significant increase of IgG GMC and OPA GMT. These are the first clinical results of PCV7-TT in children and they pave the way toward next clinical trials in children and infants. This clinical trial was published in the Cuban Public Register of Clinical Trials with code RPCEC00000173.
Dicker, Alison J.; Inglis, Neil F.; Manson, Erin D. T.; Subhadra, Subhra; Illangopathy, Manikkavasagan; Muthusamy, Raman; Knox, David P.
Background Gastrointestinal nematode infections, such as Haemonchus contortus and Mecistocirrus digitatus, are ranked in the top twenty diseases affecting small-holder farmers' livestock, yet research into M. digitatus, which infects cattle and buffalo in Asia is limited. Intestine-derived native protein vaccines are effective against Haemonchus, yet the protective efficacy of intestine-derived M. digitatus proteins has yet to be determined. Methodology/Principal Findings A simplified protein extraction protocol (A) is described and compared to an established method (B) for protein extraction from H. contortus. Proteomic analysis of the H. contortus and M. digitatus protein extracts identified putative vaccine antigens including aminopeptidases (H11), zinc metallopeptidases, glutamate dehydrogenase, and apical gut membrane polyproteins. A vaccine trial compared the ability of the M. digitatus extract and two different H. contortus extracts to protect sheep against H. contortus challenge. Both Haemonchus fractions (A and B) were highly effective, reducing cumulative Faecal Egg Counts (FEC) by 99.19% and 99.89% and total worm burdens by 87.28% and 93.64% respectively, compared to the unvaccinated controls. There was no effect on H. contortus worm burdens following vaccination with the M. digitatus extract and the 28.2% reduction in cumulative FEC was not statistically significant. However, FEC were consistently lower in the M. digitatus extract vaccinates compared to the un-vaccinated controls from 25 days post-infection. Conclusions/Significance Similar, antigenically cross-reactive proteins are found in H. contortus and M. digitatus; this is the first step towards developing a multivalent native vaccine against Haemonchus species and M. digitatus. The simplified protein extraction method could form the basis for a locally produced vaccine against H. contortus and, possibly M. digitatus, in regions where effective cold chains for vaccine distribution are limited
Evangeli, Michael; Kafaar, Zuhayr; Kagee, Ashraf; Swartz, Leslie; Bullemor-Day, Philippa
It is vital that enough participants are willing to participate in clinical trials to test HIV vaccines adequately. It is, therefore, necessary to explore what affects peoples' willingness to participate (WTP) in such trials. Studies have only examined individual factors associated with WTP and not the effect of messages about trial participation on potential participants (e.g., whether losses or gains are emphasized, or whether the outcome is certain or uncertain). This study explores whether the effects of message framing on WTP in a hypothetical HIV vaccine trial are consistent with Prospect Theory. This theory suggests that people are fundamentally risk averse and that (1) under conditions of low risk and high certainty, gain-framed messages will be influential (2) under conditions of high risk and low certainty, loss-framed messages will be influential. This cross-sectional study recruited 283 HIV-negative students from a South African university who were given a questionnaire that contained matched certain gain-framed, certain loss-framed, uncertain gain-framed, and uncertain loss-framed statements based on common barriers and facilitators of WTP. Participants were asked to rate how likely each statement was to result in their participation in a hypothetical preventative HIV vaccine trial. Consistent with Prospect Theory predictions, for certain outcomes, gain-framed messages were more likely to result in WTP than loss-framed messages. Inconsistent with predictions, loss-framed message were not more likely to be related to WTP for uncertain outcomes than gain-framed messages. Older students were less likely to express their WTP across the different message frames. Recruitment for HIV vaccine trials should pay attention to how messages about the trial are presented to potential participants.
Noya, O; Gabaldón Berti, Y; Alarcón de Noya, B; Borges, R; Zerpa, N; Urbáez, J D; Madonna, A; Garrido, E; Jimenéz, M A; Borges, R E
A phase III malaria vaccine trial in 13 villages in an endemic area, South Venezuela, compared incidence rates of Plasmodium falciparum and Plasmodium vivax infections in 1422 vaccinated and 938 nonvaccinated subjects over 18 months. The SPf66 vaccine was given in three doses, on days 0, 20, and 112. Vaccination was complete in 976 subjects (68.7%). Minor side effects requiring no treatment were reported by 123 (12.6%), with an apparent increase in frequency from the first to the third vaccine dose. No autoimmune evidence was observed in a sample of subjects. Antibodies against SPf66 were present at low titers in 24.7% of tested subjects before vaccination, increasing to 53.6% after the second dose and to 73.6% after the third dose; 26.4% of subjects initially seronegative never seroconverted. The SPf66 malaria vaccine showed a protective efficacy of 55% (95% confidence interval, 21%-75%) against P. falciparum and of 41% (19%-57%) against P. vivax malaria.
Pyzer, Athalia R; Avigan, David E; Rosenblatt, Jacalyn
The potential for the immune system to target hematological malignancies is demonstrated in the allogeneic transplant setting, where durable responses can be achieved. However, allogeneic transplantation is associated with significant morbidity and mortality related to graft versus host disease. Cancer immunotherapy has the capacity to direct a specific cytotoxic immune response against cancer cells, particularly residual cancer cells, in order to reduce the likelihood of disease relapse in a more targeted and tolerated manner. Ex vivo dendritic cells can be primed in various ways to present tumor associated antigen to the immune system, in the context of co-stimulatory molecules, eliciting a tumor specific cytotoxic response in patients. Several approaches to prime dendritic cells and overcome the immunosuppressive microenvironment have been evaluated in pre-clinical and early clinical trials with promising results. In this review, we summarize the clinical data evaluating dendritic cell based vaccines for the treatment of hematological malignancies. PMID:25625926
Ali, Asad; Kazi, Abdul Momin; Cortese, Margaret M.; Fleming, Jessica A.; Moon, SungSil; Parashar, Umesh D.; Jiang, Baoming; McNeal, Monica M.; Steele, Duncan; Bhutta, Zulfiqar; Zaidi, Anita K. M.
Background Breast milk contains anti-rotavirus IgA antibodies and other innate immune factors that inhibit rotavirus replication in vitro. These factors could diminish the immunogenicity of oral rotavirus vaccines, particularly if breastfeeding occurs close to the time of vaccine administration. Methods Between April 2011 and November 2012, we conducted an open label, randomized trial to compare the immunogenicity of Rotarix (RV1) in infants whose breastfeeding was withheld one hour before through one hour after vaccination with that in infants breastfed at the time of vaccination. The trial was conducted in the peri-urban area of Ibrahim Hyderi in Karachi, Pakistan. Both groups received three doses of RV1 at 6, 10 and 14 weeks of age. Seroconversion (anti-rotavirus IgA antibodies ≥20 U/mL in subjects seronegative at 6 weeks of age) following three vaccine doses (6, 10 and 14 weeks) was determined at 18 weeks of age (primary objective) and seroconversion following two doses (6 and 10 weeks) was determined at 14 weeks of age (secondary objective). Results Four hundred eligible infants were randomly assigned in a 1:1 ratio between the withholding breastfeeding and immediate breastfeeding arms. Overall, 353 (88.3%) infants completed the study according to protocol; 181 in the withholding breastfeeding group and 172 in the immediate breastfeeding group. After three RV1 doses, anti-rotavirus IgA antibody seroconversion was 28.2% (95% CI: 22.1; 35.1) in the withholding arm and 37.8% (95% CI: 30.9; 45.2) in the immediate breastfeeding arm (difference: -9.6% [95% CI: -19.2; 0.2] p=0.07). After two doses of RV1, seroconversion was 16.6% (95% CI: 11.9; 22.7) in the withholding arm and 29.1% (95% CI: 22.8, 36.3) in the immediate breastfeeding arm (difference: -12.5% [95% CI: -21.2,-3.8] p=0.005). Conclusions Withholding breastfeeding around the time of RV1 vaccine administration did not lead to increased anti-rotavirus IgA seroconversion compared with that seen with a
Mahendran, Radha; Jeyabaskar, Suganya; Sitharaman, Gayathri; Michael, Rajamani Dinakaran; Paul, Agnal Vincent
Edwardsiella tarda and Flavobacterium columnare are two important intracellular pathogenic bacteria that cause the infectious diseases edwardsiellosis and columnaris in wild and cultured fish. Prediction of major histocompatibility complex (MHC) binding is an important issue in T-cell epitope prediction. In a healthy immune system, the T-cells must recognize epitopes and induce the immune response. In this study, T-cell epitopes were predicted by using in silico immunoinformatics approach with the help of bioinformatics tools that are less expensive and are not time consuming. Such identification of binding interaction between peptides and MHC alleles aids in the discovery of new peptide vaccines. We have reported the potential peptides chosen from the outer membrane proteins (OMPs) of E. tarda and F. columnare, which interact well with MHC class I alleles. OMPs from E. tarda and F. columnare were selected and analyzed based on their antigenic and immunogenic properties. The OMPs of the genes TolC and FCOL_04620, respectively, from E. tarda and F. columnare were taken for study. Finally, two epitopes from the OMP of E. tarda exhibited excellent protein–peptide interaction when docked with MHC class I alleles. Five epitopes from the OMP of F. columnare had good protein–peptide interaction when docked with MHC class I alleles. Further in vitro studies can aid in the development of potential peptide vaccines using the predicted peptides. PMID:27284239
Ickenroth, Martine H. P.; Grispen, J. E. J.; de Vries, N. K.; Dinant, G. J.; Ronda, G.; van der Weijden, T.
Currently, there are many diagnostic self-tests on body materials available to consumers. The aim of this study was to assess the effect of an online decision aid on diagnostic self-testing for cholesterol and diabetes on knowledge among consumers with an intention to take these tests. A randomized controlled trial was designed. A total of 1259…
Domek, Gretchen J.; Contreras-Roldan, Ingrid L.; O’Leary, Sean T.; Bull, Sheana; Furniss, Anna; Kempe, Allison; Asturias, Edwin J.
Background Patient reminder systems are an evidence-based way to improve childhood vaccination rates but are difficult to implement in low- and middle-income countries (LMICs). Short Message Service (SMS) texts may offer a potential low-cost solution, especially in LMICs where mobile phones are becoming more ubiquitous. Objective To determine if an SMS-based vaccination reminder system aimed at improving completion of the infant primary immunization series is feasible and acceptable in Guatemala. Methods A pilot randomized controlled trial was conducted at two public health clinics in Guatemala City. Infants aged 8–14 weeks presenting for the first dose of the primary immunization series were enrolled in March–April 2013. Participants randomized into the intervention received three SMS reminders one week before the second and third dose. A follow-up acceptability survey was administered to both groups. Results The participation rate was 86.8% (321/370); 8 did not own a cell phone and 12 could not use SMS. 96.9% of intervention parents were sent at least one SMS reminder prior to visit 2 and 96.3% prior to visit 3. Both intervention and usual care participants had high rates of vaccine and visit completion, with a non-statistically significant higher percentage of children in the intervention completing both visit 2 (95.0% vs. 90.1%, p = .12) and visit 3 (84.4% vs. 80.7%, p = .69). More intervention vs. usual care parents agreed that SMS reminders would be helpful for remembering appointments (p < .0001), agreed to being interested in receiving future SMS reminders (p < .0001), and said that they would be willing to pay for future SMS reminders (p = .01). Conclusion This proof of concept evaluation showed that a new application of SMS technology is feasible to implement in a LMIC with high user satisfaction. Larger studies with modifications in the SMS system are needed to determine effectiveness (Clinical Trial Registry NCT01663636). PMID:27026145
Edinboro, Charlotte H; Ward, Michael P; Glickman, Larry T
A placebo-controlled field trial was conducted to compare the effectiveness of intranasal (IN) vaccines containing Bordetella bronchiseptica and canine-parainfluenza virus, with (IN-BPA) or without (IN-BP) canine-adenovirus type 2, for prevention of kennel cough at a humane shelter. Dogs were examined on admission to the shelter and those without respiratory signs of disease were assigned daily, on a rotating basis, to receive one of three vaccines. We enrolled 972 healthy dogs. Dogs were monitored for up to 30 days post-vaccination for coughing and other clinical signs of respiratory disease. Thirty-three (10.7%; 95% confidence interval (CI): 7.2%, 14.2%) dogs in the IN-BP group, 36 (10.2%; CI: 7.0%, 13.4%) [corrected] dogs in the IN-BPA group, and 42 (13.5%; CI: 9.7%, 17.3%) [corrected] dogs in the IN-P group coughed spontaneously for > or = 1 day within 30 days of vaccination (P = 0.37). The IN-BP and IN-BPA vaccines were 20.7 and 24.4% effective, respectively, in reducing coughing compared with a placebo vaccine. The strongest prognostic factor for coughing (regardless of vaccine group) was the number of days spent at the shelter, with each additional day increasing the risk of coughing by 3% (95% CI: 1.01, 1.06) [corrected] The low incidence of coughing in the shelter during this study precluded observation of differences in vaccine effectiveness. No differences in vaccine-associated adverse events (coughing, sneezing, nasal or ocular discharge) were noted during the first 3 days post-administration or thereafter.
Wang, F; Bade, E; Kuniyoshi, C; Spears, L; Jeffery, G; Marty, V; Groshen, S; Weber, J
Twenty-five patients with high-risk resected stages IIB, III, and IV melanoma were immunized with a vaccine consisting of the minimal epitope, immunodominant 9-amino acid peptide derived from the MART-1 tumor antigen (AAGIGILTV) complexed with incomplete Freund's adjuvant. The last three patients received the MART-1(27-35) peptide with incomplete Freund's adjuvant mixed with CRL 1005, a block copolymer adjuvant. Patients were immunized with increasing doses of the MART-1(27-35) peptide in a Phase I trial to evaluate the toxicity, tolerability, and immune responses to the vaccine. Immunizations were administered every 3 weeks for a total of four injections, preceded by leukapheresis to obtain peripheral blood mononuclear cells for immune analyses, followed by a post-vaccine leukapheresis 3 weeks after the fourth vaccination. Skin testing with peptide and standard delayed-type hypersensitivity skin test reagents was also performed before and after vaccinations. Local pain and granuloma formation were observed in the majority of patients, as were fevers or lethargy of grade 1 or 2. No vaccine-related grade III/IV toxicity was observed. The vaccine was felt to be well tolerated. Twelve of 25 patients were anergic to skin testing at the initiation of the trial, and 13 of 25 developed a positive skin test response to the MART-1(27-35) peptide. Immune responses were measured by release of IFN-gamma in an ELISA assay by effector cells after multiple restimulations of peripheral blood mononuclear cells in the presence of MART-1(27-35) peptide-pulsed antigen-presenting cells. An ELISPOT assay was also developed to measure more quantitatively the change in numbers of peptide-specific effector cells after vaccination. Ten of 22 patients demonstrated an immune response to peptide-pulsed targets or tumor cells by ELISA assay after vaccination, as did 12 of 20 patients by ELISPOT. Nine of 25 patients have relapsed with a median of 16 months of follow-up, and 3 patients in this
Mertz, Dominik; Fadel, Shaza A.; Lam, Po-Po; Tran, Dat; Srigley, Jocelyn A; Asner, Sandra A; Science, Michelle; Kuster, Stefan P; Nemeth, Johannes; Johnstone, Jennie; Ortiz, Justin R; Loeb, Mark
Influenza vaccination programmes are assumed to have a herd effect and protect contacts of vaccinated persons from influenza virus infection. We searched MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Global Health and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to March 2014 for studies assessing the protective effect of influenza vaccination vs no vaccination on influenza virus infections in contacts. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using a random-effects model. Of 43,082 screened articles, nine randomised controlled trials (RCTs) and four observational studies were eligible. Among the RCTs, no statistically significant herd effect on the occurrence of influenza in contacts could be found (OR: 0.62; 95% CI: 0.34–1.12). The one RCT conducted in a community setting, however, showed a significant effect (OR: 0.39; 95% CI: 0.26–0.57), as did the observational studies (OR: 0.57; 95% CI: 0.43–0.77). We found only a few studies that quantified the herd effect of vaccination, all studies except one were conducted in children, and the overall evidence was graded as low. The evidence is too limited to conclude in what setting(s) a herd effect may or may not be achieved. PMID:27784531
Sun, Yanqing; Li, Mei; Gilbert, Peter B.
For time-to-event data with finitely many competing risks, the proportional hazards model has been a popular tool for relating the cause-specific outcomes to covariates (Prentice and others, 1978. The analysis of failure time in the presence of competing risks. Biometrics 34, 541–554). Inspired by previous research in HIV vaccine efficacy trials, the cause of failure is replaced by a continuous mark observed only in subjects who fail. This article studies an extension of this approach to allow a multivariate continuum of competing risks, to better account for the fact that the candidate HIV vaccines tested in efficacy trials have contained multiple HIV sequences, with a purpose to elicit multiple types of immune response that recognize and block different types of HIV viruses. We develop inference for the proportional hazards model in which the regression parameters depend parametrically on the marks, to avoid the curse of dimensionality, and the baseline hazard depends nonparametrically on both time and marks. Goodness-of-fit tests are constructed based on generalized weighted martingale residuals. The finite-sample performance of the proposed methods is examined through extensive simulations. The methods are applied to a vaccine efficacy trial to examine whether and how certain antigens represented inside the vaccine are relevant for protection or anti-protection against the exposing HIVs. PMID:22764174
Raviotta, Jonathan M; Nowalk, Mary Patricia; Lin, Chyongchiou Jeng; Huang, Hsin-Hui; Zimmerman, Richard K
College-age men were recruited using Facebook™ advertisements (ads), as well as traditional recruitment methods, for a randomized controlled trial to compare immunological responses to human papillomavirus vaccine administered in two dosing schedules. This study compares enrollees who were recruited through traditional recruitment methods versus social networking sites (SNSs), including Facebook. Potential participants were recruited using flyers posted on and off campus(es), and distributed at health fairs, classes, sporting, and other campus events; e-mails to students and student organizations; and print advertisements in student newspapers and on city buses. Facebook ads were displayed to users with specific age, geographic, and interest characteristics; ads were monitored daily to make adjustments to improve response. A total of 220 males, aged 18 to 25 years enrolled between October 2010 and May 2011. The majority of participants (51%) reported print advertisements as the method by which they first heard about the study, followed by personal contact (29%) and Facebook or other SNSs (20%). The likelihood of a SNS being the source by which the participant first heard about the study compared with traditional methods was increased if the participant reported (a) being homosexual or bisexual or (b) posting daily updates on SNSs. Facebook and other SNSs are a viable recruitment strategy for reaching potential clinical trial participants among groups who typically use social media to stay connected with their friends and hard-to-reach groups such as young men who self-identify as homosexual or bisexual.
Albright, Kendra S.; Gavigan, Karen
HIV/AIDS infections are growing at an alarming rate for young adults. In 2009, youth, ages 13-29, accounted for 39% of all new HIV infections in the U.S. (Division of HIV/ AIDS Prevention, Centers for Disease Control (CDC), 2011). South Carolina ranks eighth in the nation for new HIV cases, while the capital city of Columbia ranks seventh…
Karagiannis, Thomas; Liakos, Aris; Branda, Megan E; Athanasiadou, Eleni; Mainou, Maria; Boura, Panagiota; Goulis, Dimitrios G; LeBlanc, Annie; Montori, Victor M
Objective To assess the efficacy of the Diabetes Medication Choice Decision Aid among patients with type 2 diabetes in Greece. Design Open-label cluster randomised controlled trial. Setting Primary and secondary care practices across Greece. Participants 5 sites allocated to the decision aid (n=101 patients) and 4 sites to control (n=103 patients). Intervention Clinicians and patients in the intervention arm used a decision aid, based on outcomes that both consider important when choosing among antihyperglycaemic medications. Patients in the control arm received usual care. Outcome measures The primary outcome was patient's level of decisional comfort after the initial clinical encounter. Secondary outcomes included patient's knowledge about type 2 diabetes and medications, and patient's and clinician's satisfaction. Adherence to prescribed antihyperglycaemic medication and change in glycated haemoglobin were assessed at 24 weeks. Results Patients in both arms had similar scores in overall decisional comfort (mean difference between the usual care and decision aid arms −6.9, 95% CI −21.5 to 7.7) and its subscales. Patients' knowledge was high in both arms (mean difference 2.3%, 95% CI −15.7% to 20.4%). Patients and clinicians in both groups were equally satisfied with the decision-making. No significant difference in medication adherence and glycaemic control was found across arms. Clinicians found the decision aid useful and reported that its integration in their daily routine was easy. Conclusions The decision aid was implemented and positively received in the clinical setting in Greece, in line with the patient-centred approach endorsed by current guidelines. However, this trial yielded imprecise results in terms of patient outcomes. Further research is needed to investigate the interaction between the patient and the clinician in order to clarify the association between the use of decision aids and implementation of shared decision-making. Trial
Dayer, Julie-Anne; Siegrist, Claire-Anne; Huttner, Angela
The continued participation of volunteers in clinical trials is crucial to advances in healthcare. Few data are available regarding the satisfaction and impressions of healthy volunteers after participation in phase I trials, many of which lead to unexpected adverse events. We report feedback from over 100 adult volunteers who took part in a first-in-human trial conducted in a high-income country testing an experimental Ebola vaccine causing significant reactogenicity, as well as unexpected arthritis in one fifth of participants. The anonymous, internet-based satisfaction survey was sent by email to all participants upon their completion of this one-year trial; it asked 24 questions concerning volunteers’ motivations, impressions of the trial experience, and overall satisfaction. Answers were summarized using descriptive statistics. Of the 115 trial participants, 103 (90%) filled out the survey. Fifty-five respondents (53%) were male. Thirty-five respondents (34%) were healthcare workers, many of whom would deploy to Ebola-affected countries. All respondents cited scientific advancement as their chief motivation for participation, while 100/103 (97%) and 61/103 (59%) reported additional “humanitarian reasons” and potential protection from Ebolavirus, respectively. Although investigators had documented adverse events in 97% of trial participants, only 74 of 103 respondents (72%) recalled experiencing an adverse event. All reported an overall positive experience, and 93/103 (90%) a willingness to participate in future trials. Given the high level of satisfaction, no significant associations could be detected between trial experiences and satisfaction, even among respondents reporting adverse events lasting weeks or months. Despite considerable reactogenicity and unexpected vaccine-related arthritis, all survey respondents reported overall satisfaction. While this trial’s context was unique, the positive feedback is likely due at least in part to the intense
Some have argued that the vaccine against malaria developed by Manuel Pattaroyo, a Colombian scientist, is being tested prematurely in humans and that it is unlikely to be successful. While the Pattaroyo vaccine has been shown to confer protection against the relatively mild malaria found in Colombia, doubts exist over whether it will be effective in Africa. Encouraging first results, however, are emerging from field tests in Tanzania. The vaccine triggered a strong new immune response, even in individuals previously exposed to malaria. Additional steps must be taken to establish its impact upon mortality and morbidity. Five major trials are underway around the world. The creator estimates that the first ever effective malaria vaccine could be available for widespread use within five years and he has no intention of securing a patent for the discovery. In another development, malaria specialists from 35 African countries convened at an international workshop in Zimbabwe to compare notes. Participants disparaged financial outlays for the fight against malaria equivalent to 2% of total AIDS funding as insufficient; noted intercountry differences in prevention, diagnosis, and treatment; and found information exchange between anglophone and francophone doctors to be generally poor.
Wang, Biao; Russell, Margaret L.; Moss, Lorraine; Fonseca, Kevin; Earn, David J. D.; Aoki, Fred; Horsman, Gregory; Caeseele, Paul Van; Chokani, Khami; Vooght, Mark; Babiuk, Lorne; Webby, Richard; Walter, Stephen D.; Loeb, Mark
Background An earlier cluster randomized controlled trial (RCT) of Hutterite colonies had shown that if more than 80% of children and adolescents were immunized with influenza vaccine there was a statistically significant reduction in laboratory-confirmed influenza among all unimmunized community members. We assessed the impact of this intervention for two additional influenza seasonal periods. Methods Follow-up data for two influenza seasonal periods of a cluster randomized trial involving 1053 Canadian children and adolescents aged 36 months to 15 years in Season 2 and 1014 in Season 3 who received the study vaccine, and 2805 community members in Season 2 and 2840 in Season 3 who did not receive the study vaccine. Follow-up for Season 2 began November 18, 2009 and ended April 25, 2010 while Season 3 extended from December 6, 2010 and ended May 27, 2011. Children were randomly assigned in a blinded manner according to community membership to receive either inactivated trivalent influenza vaccine or hepatitis A. The primary outcome was confirmed influenza A and B infection using RT-PCR assay. Due to the outbreak of 2009 H1N1 pandemic, data in Season 2 were excluded for analysis. Results For an analysis of the combined Season 1 and Season 3 data, among non-recipients (i.e., participants who did not receive study vaccines), 66 of the 2794 (2.4%) participants in the influenza vaccine colonies and 121 of the 2301 (5.3%) participants in the hepatitis A colonies had influenza confirmed by RT-PCR, for a protective effectiveness of 60% (95% CI, 6% to 83%; P = 0.04); among all study participants (i.e., including both those who received study vaccine and those who did not), 125 of the 3806 (3.3%) in the influenza vaccine colonies and 239 of the 3243 (7.4%) in the hepatitis A colonies had influenza confirmed by RT-PCR, for a protective effectiveness of 63% (95% CI, 5% to 85%; P = 0.04). Conclusion Immunizing children and adolescents with inactivated influenza vaccine can
Girard, Marc P; Katz, Jacqueline M; Pervikov, Yuri; Hombach, Joachim; Tam, John S
On February 17-18, 2011, the World Health Organization convened the 7th meeting on "The Evaluation of Pandemic Influenza Vaccines in Clinical Trials" to review the progress made on pandemic A (H1N1) 2009 vaccines and the evaluation of their effectiveness in the field, especially in children less than 3 years of age and in pregnant women. Other topics to be addressed included a comparison of egg- and cell culture-based influenza vaccines, technical issues related to vaccine strain development and vaccine potency, and the status of development of prototype influenza vaccines using new technologies. Pandemic A (H1N1) vaccines were safe in young children, pregnant women and immunocompromized individuals. Overall effectiveness of inactivated A (H1N1) vaccines for all ages was found to vary between 72% and 100% in different countries and with different vaccine preparations. Effectiveness of pandemic A (H1N1) 2009 live attenuated vaccine was estimated to be approximately 80% in pediatric populations in the USA. A single dose of inactivated vaccine adjuvanted with AS03, MF59 or AF03 induced protective immunity in young children and pregnant women. However, unadjuvanted vaccines as well as low dose adjuvanted vaccines (1.9 μg HA) required two doses to elicit protective antibody levels in these populations. Clinical trials of influenza vaccines developed using new technologies showed they were well tolerated and induced antibody and/or T cell immune responses to viral proteins. Further studies are warranted to validate novel immunological criteria for evaluation and licensing of such new influenza vaccine concepts. On the regulatory side, work should be undertaken to harmonize the results of serological tests used to evaluate the immunogenicity of traditional influenza vaccines.
Karussis, Dimitrios; Shor, Hagai; Yachnin, Julia; Lanxner, Naama; Amiel, Merav; Baruch, Keren; Keren-Zur, Yael; Haviv, Ofra; Filippi, Massimo; Petrou, Panayiota; Hajag, Shalom; Vourka-Karussis, Urania; Vaknin-Dembinsky, Adi; Khoury, Salim; Abramsky, Oded; Atlan, Henri; Cohen, Irun R.; Abulafia-Lapid, Rivka
Background T-cell vaccination (TCV) for multiple sclerosis (MS) refers to treatment with autologous anti-myelin T-cells, attenuated by irradiation. Previously published clinical trials have been all open-labeled. Aim To evaluate the safety and efficacy of TCV in progressive MS, in a double-blind, controlled clinical trial. Methodology Twenty-six patients with relapsing-progressive MS were enrolled in the study (mean age: 39±9.8 years; mean EDSS: 4.4±1.7). T-cell lines reactive to 9 different peptides of the myelin antigens, MBP, MOG and PLP were raised from the patients' peripheral blood. The patients were randomized into two groups: 19 were treated with TCV (four subcutaneous injections of 10–30×106 T-cells, attenuated by irradiation, on days 1, 30, 90 and 180) and 7 patients were treated with sham injections. Twenty-four patients (17 in the TCV group and 7 in the placebo) were eligible for per-protocol analysis. Results At one year following the inclusion, an increase in the EDSS (+0.50) and an increase in 10-meter walking time (+0.18 sec), were observed in the placebo group; in the TCV group there was a decrease in the EDSS (−0.44; p<0.01) and in the 10-meter walking time (0.84 sec; p<0.005). Sixteen of the 17 patients (94.1%) in the TCV group remained relapse-free during the year of the study, as compared to 42.9% in the placebo group (p = 0.01 and p = 0.03 with adjustment). The proportion of patients with any relapse during the year of the study in the TCV-group, was reduced by 89.6%., as compared to the placebo-treated group. MRI parameters did not change significantly. Conclusions This is the first controlled, double-blind trial with TCV in progressive MS. The results demonstrate the feasibility and safety of the procedure, and provide significant indications of clinical efficacy. Further studies with larger groups of subjects are warranted. Trial Registration ClinicalTrials.gov NCT01448252 PMID:23272061
Saunders, Kevin O; Rudicell, Rebecca S; Nabel, Gary J
There is renewed optimism that the goal of developing a highly effective AIDS vaccine is attainable. The HIV-1 vaccine field has seen its first trial of a vaccine candidate that prevents infection. Although modest in efficacy, this finding, along with the recent discovery that the human immune system can produce broadly neutralizing antibodies capable of inhibiting greater than 90% of circulating viruses, provides a guide for the rational design of vaccines and protection by passive immunization. Together, these findings will help shape the next generation of HIV vaccines.
The best long-term hope for controlling the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) pandemic is a safe, effective and affordable preventive vaccine, but its development has encountered unprecedented scientific challenges. The first phase I trial of an HIV vaccine was conducted in 1987. Subsequently, more than 30 candidate vaccines have been tested in over 60 phase I/II trials, involving approximately 10 000 healthy volunteers. Most of these trials have been conducted in the USA and Europe, but several have also been conducted in developing countries. The first phase III trials began in the USA in 1998 and in Thailand in 1999 to assess the efficacy of the first generation of HIV vaccines (based on the HIV envelope protein, gp120); the results will be available within the next 1-2 years. To accelerate the development of an HIV vaccine, additional candidate vaccines must be evaluated in parallel in both industrialized and developing countries. This will require international collaboration and coordination and critical ethical issues will need to be addressed. To ensure that future HIV vaccines contribute to the overall HIV/AIDS prevention effort, we should begin planning now on how best to use them. PMID:11799445
Yoo, Byung-Kwang; Humiston, Sharon G; Szilagyi, Peter G; Schaffer, Stanley J; Long, Christine; Kolasa, Maureen
School-located vaccination against influenza (SLV-I) has been suggested to help meet the need for annual vaccination of large numbers of school-aged children with seasonal influenza vaccine. However, little is known about the cost and cost-effectiveness of SLV-I. We conducted a cost-analysis and a cost-effectiveness analysis based on a randomized controlled trial (RCT) of an SLV-I program implemented in Monroe County, New York during the 2009-2010 vaccination season. We hypothesized that SLV-I is more cost effective, or less-costly, compared to a conventional, office-located influenza vaccination delivery. First and second SLV-I clinics were offered in 21 intervention elementary schools (n=9027 children) with standard of care (no SLV-I) in 11 control schools (n=4534 children). The direct costs, to purchase and administer vaccines, were estimated from our RCT. The effectiveness measure, receipt of ≥1 dose of influenza vaccine, was 13.2 percentage points higher in SLV-I schools than control schools. The school costs ($9.16/dose in 2009 dollars) plus project costs ($23.00/dose) plus vendor costs excluding vaccine purchase ($19.89/dose) was higher in direct costs ($52.05/dose) than the previously reported mean/median cost [$38.23/$21.44 per dose] for providing influenza vaccination in pediatric practices. However SLV-I averted parent costs to visit medical practices ($35.08 per vaccine). Combining direct and averted costs through Monte Carlo Simulation, SLV-I costs were $19.26/dose in net costs, which is below practice-based influenza vaccination costs. The incremental cost-effectiveness ratio (ICER) was estimated to be $92.50 or $38.59 (also including averted parent costs). When additionally accounting for the costs averted by disease prevention (i.e., both reduced disease transmission to household members and reduced loss of productivity from caring for a sick child), the SLV-I model appears to be cost-saving to society, compared to "no vaccination". Our findings
considered causally related to vaccination. Conclusions PHiD-CV had a clinically acceptable safety profile when co-administered with DTPa-HBV-IPV/Hib in Vietnamese infants. The reactogenicity of PHiD-CV was comparable to that observed in other South-East Asian populations. Trial registration ClinicalTrials.gov: http://NCT01153841 PMID:23432812
de la Torre, Ana; Hernandez, Julio; Ortiz, Ramón; Cepeda, Meylán; Perez, Kirenia; Car, Adriana; Viada, Carmen; Toledo, Darién; Guerra, Pedro Pablo; García, Elena; Arboláez, Migdacelys; Fernandez, Luis E
Patients treated with vaccines based on NGlycolil gangliosides have showed benefit in progression free survival and overall survival. These molecules, which have been observed in breast cancer cells, are minimally or not expressed in normal human tissue and have been considered as antigen tumor-specific. For this reason they are very attractive to immunotherapy. A phase I/II clinical trial was carried out in metastatic breast cancer patients with the NGlycolylGM3/VSSP vaccine administered by subcutaneous route. Selecting the optimal biological doses of the vaccine in these patients was the principal objective based on the immunogenicity, efficacy and safety results. Six levels of doses of vaccine were studied. Treatment schedule consisted of five doses every two weeks and then monthly until reaching a fifteenth doses. Doses levels studied were 150, 300, 600, 900, 1200 and 1500 μg. Five patients in each level were included except at the 900 μg dose, in which ten patients were included. Immunogenicity was determined by levels of antibodies generated in patients after vaccination. The response criteria of evaluation in solid tumors (RECIST) was used to evaluate antitumoral effect. Safety was evaluated by Common Toxicity Criteria of Adverse Event (CTCAE). The vaccine administration was safe and immunogenic in all does levels. Most frequent adverse events related to vaccination were mild or moderate and were related to injection site reactions and “flu-like” symptoms. Vaccination induced specific anti-NeuGcGM3 IgM and IgG antibodies responses in all patients. Disease control (objective response or stable disease) was obtained in 72.7% of evaluated patients. Median overall survival was 15.9 months. Two patients of two different dose levels achieved overall survival values of about six years. The dose of 900 μg was selected as biological optimal dose in which overall survival was 28.5 months. PMID:23055739
de la Torre, Ana; Hernandez, Julio; Ortiz, Ramón; Cepeda, Meylán; Perez, Kirenia; Car, Adriana; Viada, Carmen; Toledo, Darién; Guerra, Pedro Pablo; García, Elena; Arboláez, Migdacelys; Fernandez, Luis E
Patients treated with vaccines based on NGlycolil gangliosides have showed benefit in progression free survival and overall survival. These molecules, which have been observed in breast cancer cells, are minimally or not expressed in normal human tissue and have been considered as antigen tumor-specific. For this reason they are very attractive to immunotherapy. A phase I/II clinical trial was carried out in metastatic breast cancer patients with the NGlycolylGM3/VSSP vaccine administered by subcutaneous route. Selecting the optimal biological doses of the vaccine in these patients was the principal objective based on the immunogenicity, efficacy and safety results. Six levels of doses of vaccine were studied. Treatment schedule consisted of five doses every two weeks and then monthly until reaching a fifteenth doses. Doses levels studied were 150, 300, 600, 900, 1200 and 1500 μg. Five patients in each level were included except at the 900 μg dose, in which ten patients were included. Immunogenicity was determined by levels of antibodies generated in patients after vaccination. The response criteria of evaluation in solid tumors (RECIST) was used to evaluate antitumoral effect. Safety was evaluated by Common Toxicity Criteria of Adverse Event (CTCAE). The vaccine administration was safe and immunogenic in all does levels. Most frequent adverse events related to vaccination were mild or moderate and were related to injection site reactions and "flu-like" symptoms. Vaccination induced specific anti-NeuGcGM3 IgM and IgG antibodies responses in all patients. Disease control (objective response or stable disease) was obtained in 72.7% of evaluated patients. Median overall survival was 15.9 months. Two patients of two different dose levels achieved overall survival values of about six years. The dose of 900 μg was selected as biological optimal dose in which overall survival was 28.5 months.
Taddio, Anna; Smart, Sarah; Sheedy, Matthuschka; Yoon, Eugene W; Vyas, Charmy; Parikh, Chaitya; Pillai Riddell, Rebecca; Shah, Vibhuti
Analgesic interventions are not routinely used during vaccine injections in infants. Parents report a desire to mitigate injection pain, but lack the knowledge about how to do so. The objective of this cluster-randomized trial was to evaluate the effect of a parent-directed prenatal education teaching module about vaccination pain management on analgesic utilization at future infant vaccinations. Expectant mothers enrolled in prenatal classes at Mount Sinai Hospital in Toronto were randomized to a 20-30minute interactive presentation about vaccination pain management (experimental group) or general vaccination information (control group). Both presentations included a PowerPoint (Microsoft Corporation, Redmond, WA, USA) and video presentation, take-home pamphlet, and "Question and Answer" period. The primary outcome was self-reported utilization of breastfeeding, sugar water, or topical anaesthetics at routine 2-month infant vaccinations. Between October 2012 and July 2013, 197 expectant mothers from 28 prenatal classes participated; follow-up was obtained in 174 (88%). Maternal characteristics did not differ (P>0.05) between groups. Utilization of one or more prespecified pain interventions occurred in 34% of participants in the experimental group, compared to 17% in the control group (P=0.01). Inclusion of a pain management module in prenatal classes led to increased utilization of evidence-based pain management interventions by parents at the 2-month infant vaccination appointment. Educating parents offers a novel and effective way of improving the quality of pain care delivered to infants during vaccination. Additional research is needed to determine if utilization can be bolstered further using techniques such as postnatal hospital reinforcement, reminder cards, and clinician education.
Nealon, Joshua; Taurel, Anne-Frieda; Capeding, Maria Rosario; Tran, Ngoc Huu; Hadinegoro, Sri Rezeki; Chotpitayasunondh, Tawee; Chong, Chee Kheong; Wartel, T Anh; Beucher, Sophie; Frago, Carina; Moureau, Annick; Simmerman, Mark; Laot, Thelma; L'Azou, Maïna; Bouckenooghe, Alain
Dengue incidence has increased globally, but empirical burden estimates are scarce. Prospective methods are best-able to capture all severities of disease. CYD14 was an observer-blinded dengue vaccine study conducted in children 2-14 years of age in Indonesia, Malaysia, Thailand, the Philippines, and Vietnam. The control group received no vaccine and resembled a prospective, observational study. We calculated the rates of dengue according to different laboratory or clinical criteria to make inferences about dengue burden, and compared with rates reported in the passive surveillance systems to calculate expansion factors which describe under-reporting. Over 6,933 person-years of observation in the control group there were 319 virologically confirmed dengue cases, a crude attack rate of 4.6%/year. Of these, 92 cases (28.8%) were clinically diagnosed as dengue fever or dengue hemorrhagic fever by investigators and 227 were not, indicating that most symptomatic disease fails to satisfy existing case definitions. When examining different case definitions, there was an inverse relationship between clinical severity and observed incidence rates. CYD14's active surveillance system captured a greater proportion of symptomatic dengue than national passive surveillance systems, giving rise to expansion factors ranging from 0.5 to 31.7. This analysis showed substantial, unpredictable and variable under-reporting of symptomatic dengue, even within a controlled clinical trial environment, and emphasizes that burden estimates are highly sensitive to case definitions. These data will assist in generating disease burden estimates and have important policy implications when considering the introduction and health economics of dengue prevention and control interventions.
Taurel, Anne-Frieda; Capeding, Maria Rosario; Tran, Ngoc Huu; Hadinegoro, Sri Rezeki; Chotpitayasunondh, Tawee; Chong, Chee Kheong; Wartel, T. Anh; Beucher, Sophie; Frago, Carina; Moureau, Annick; Simmerman, Mark; Laot, Thelma; L’Azou, Maïna; Bouckenooghe, Alain
Dengue incidence has increased globally, but empirical burden estimates are scarce. Prospective methods are best-able to capture all severities of disease. CYD14 was an observer-blinded dengue vaccine study conducted in children 2–14 years of age in Indonesia, Malaysia, Thailand, the Philippines, and Vietnam. The control group received no vaccine and resembled a prospective, observational study. We calculated the rates of dengue according to different laboratory or clinical criteria to make inferences about dengue burden, and compared with rates reported in the passive surveillance systems to calculate expansion factors which describe under-reporting. Over 6,933 person-years of observation in the control group there were 319 virologically confirmed dengue cases, a crude attack rate of 4.6%/year. Of these, 92 cases (28.8%) were clinically diagnosed as dengue fever or dengue hemorrhagic fever by investigators and 227 were not, indicating that most symptomatic disease fails to satisfy existing case definitions. When examining different case definitions, there was an inverse relationship between clinical severity and observed incidence rates. CYD14’s active surveillance system captured a greater proportion of symptomatic dengue than national passive surveillance systems, giving rise to expansion factors ranging from 0.5 to 31.7. This analysis showed substantial, unpredictable and variable under-reporting of symptomatic dengue, even within a controlled clinical trial environment, and emphasizes that burden estimates are highly sensitive to case definitions. These data will assist in generating disease burden estimates and have important policy implications when considering the introduction and health economics of dengue prevention and control interventions. PMID:27532617
Artnzen, C J
Vaccines were the result of trial and error research until molecular biology and genetic engineering made possible the creation of of many new and improved vaccines. New vaccines need to be inexpensive, easily administered, and capable of being stored and transported without refrigeration; without these characteristics, developing countries find it difficult to adopt vaccination as the central strategy for preventing their most devastating diseases. The authors describe a promising approach to inexpensive and effective vaccines: producing them in plants we commonly consume.
Thomas, Stephen J; Rothman, Alan L
Dengue is a rapidly expanding global health problem. Development of a safe and efficacious tetravalent vaccine along with strategic application of vector control activities represents a promising approach to reducing the global disease burden. Although many vaccine development challenges exist, numerous candidates are in clinical development and one has been tested in three clinical endpoint studies. The results of these studies have raised numerous questions about how we measure vaccine immunogenicity and how these readouts are associated with clinical outcomes in vaccine recipients who experience natural infection. In this review the authors discuss the dengue vaccine pipeline, development challenges, the dengue vaccine-immunologic profiling intersection, and research gaps.
Thomas, Stephen J; Rothman, Alan L
Dengue is a rapidly expanding global health problem. Development of a safe and efficacious tetravalent vaccine along with strategic application of vector control activities represents a promising approach to reducing the global disease burden. Although many vaccine development challenges exist, numerous candidates are in clinical development and one has been tested in three clinical endpoint studies. The results of these studies have raised numerous questions about how we measure vaccine immunogenicity and how these readouts are associated with clinical outcomes in vaccine recipients who experience natural infection. In this review the authors discuss the dengue vaccine pipeline, development challenges, the dengue vaccine-immunologic profiling intersection, and research gaps.
1 Award Number: W81XWH-10-1-0699 TITLE: Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural...WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural Mesothelioma after Completion of Multimodality Therapy 5a. CONTRACT NUMBER 5b...malignant pleural mesothelioma (MPM), and is a rational target for immunotherapy. We have developed a vaccine comprised of four WT1 heteroclitic
randomized, double-blind, controlled field trial in Santiago, Chile, 81,621 school- children , 5-19 years of age, received three doses, within one week, of...liquid formulation protected young children (5-9 year olds) (vaccine efficacy 82.3%) as well as older children (> 10 years) (69.3% vaccine efficacy...while the capsules significantly protected only older children . The liquid suspension was practical to prepare by mixing lyophilized vaccine with buffer
Analog Peptides Derived from WT1 Oncoprotein Induces T Cell Responses in Patients with Complete Remission from Acute Myeloid Leukemia (AML), Blood 2010...10-1-0699 TITLE: Randomized Phase II Trial of Adjuvant WT-1 Analog Peptide Vaccine in Patients with Malignant Pleural Mesothelioma after...vaccine comprised of four WT1 heteroclitic peptides that are given together with Montanide and GM- CSF as immunologic adjuvants. This WT1 vaccine was
Brehaut, Jamie C; Lott, Alison; Fergusson, Dean A; Shojania, Kaveh G; Kimmelman, Jonathan; Saginur, Raphael
Background Evidence shows that the standard process for obtaining informed consent in clinical trials can be inadequate, with study participants frequently not understanding even basic information fundamental to giving informed consent. Patient decision aids are effective decision support tools originally designed to help patients make difficult treatment or screening decisions. We propose that incorporating decision aids into the informed consent process will improve the extent to which participants make decisions that are informed and consistent with their preferences. A mixed methods study will test this proposal. Methods Phase one of this project will involve assessment of a stratified random sample of 50 consent documents from recently completed investigator-initiated clinical trials, according to existing standards for supporting good decision making. Phase two will involve interviews of a purposive sample of 50 trial participants (10 participants from each of five different clinical areas) about their experience of the informed consent process, and how it could be improved. In phase three, we will convert consent forms for two completed clinical trials into decision aids and pilot test these new tools using a user-centered design approach, an iterative development process commonly employed in computer usability literature. In phase four, we will conduct a pilot observational study comparing the new tools to standard consent forms, with potential recruits to two hypothetical clinical trials. Outcomes will include knowledge of key aspects of the decision, knowledge of the probabilities of different outcomes, decisional conflict, the hypothetical participation decision, and qualitative impressions of the experience. Discussion This work will provide initial evidence about whether a patient decision aid can improve the informed consent process. The larger goal of this work is to examine whether study recruitment can be improved from (barely) informed consent
Herrett, Emily; Williamson, Elizabeth; van Staa, Tjeerd; Ranopa, Michael; Free, Caroline; Chadborn, Tim; Goldacre, Ben; Smeeth, Liam
Objectives (1) To develop methods for conducting cluster randomised trials of text messaging interventions utilising routine electronic health records at low cost; (2) to assess the effectiveness of text messaging influenza vaccine reminders in increasing vaccine uptake in patients with chronic conditions. Design Cluster randomised trial with general practices as clusters. Setting English primary care. Participants 156 general practices, who used text messaging software, who had not previously used text message influenza vaccination reminders. Eligible patients were aged 18–64 in ‘at-risk’ groups. Interventions Practices were randomly allocated to either an intervention or standard care arm in the 2013 influenza season (September to December). Practices in the intervention arm were asked to send a text message influenza vaccination reminder to their at-risk patients under 65. Practices in the standard care arm were asked to continue their influenza campaign as planned. Blinding Practices were not blinded. Analysis was performed blinded to practice allocation. Main outcome measures Practice-level influenza vaccine uptake among at-risk patients aged 18–64 years. Results 77 practices were randomised to the intervention group (76 analysed, n at-risk patients=51 121), 79 to the standard care group (79 analysed, n at-risk patients=51 136). The text message increased absolute vaccine uptake by 2.62% (95% CI −0.09% to 5.33%), p=0.058, though this could have been due to chance. Within intervention clusters, a median 21.0% (IQR 10.2% to 47.0%) of eligible patients were sent a text message. The number needed to treat was 7.0 (95% CI −0.29 to 14.3). Conclusions Patient follow-up using routine electronic health records is a low cost method of conducting cluster randomised trials. Text messaging reminders are likely to result in modest improvements in influenza vaccine uptake, but levels of patients being texted need to markedly increase if text messaging
Introduction Tamoxifen and raloxifene are chemopreventive drugs that can reduce women's relative risk of primary breast cancer by 50%; however, most women eligible for these drugs have chosen not to take them. The reasons for low uptake may be related to women's knowledge or attitudes towards the drugs. We aimed to examine the impact of an online breast cancer chemoprevention decision aid (DA) on informed intentions and decisions of women at high risk of breast cancer. Methods We conducted a randomized clinical trial, assessing the effect of a DA about breast cancer chemoprevention on informed choices about chemoprevention. Women (n = 585), 46- to 74-years old old, completed online baseline, post-test, and three-month follow-up questionnaires. Participants were randomly assigned to either an intervention group, a standard control group that answered questions about chemoprevention at baseline, or a three-month control group that did not answer questions about chemoprevention at baseline. The main outcome measures were whether women's intentions and decisions regarding chemoprevention drugs were informed, and whether women who viewed the DA were more likely to make informed decisions than women who did not view the DA, using a dichotomous composite variable 'informed choice' (yes/no) to classify informed decisions as those reflecting sufficient knowledge and concordance between a woman's decision and relevant attitudes. Results Analyses showed that more intervention than standard control participants (52.7% versus 5.9%) made informed decisions at post-test, P <0.001. At the three-month follow-up, differences in rates of informed choice between intervention (16.9%) and both control groups (11.8% and 8.0%) were statistically non-significant, P = 0.067. Conclusions The DA increased informed decision making about breast cancer chemoprevention, although the impact on knowledge diminished over time. This study was not designed to determine how much knowledge decision
Verma, Shefali S.; Frase, Alex T.; Verma, Anurag; Pendergrass, Sarah A.; Mahony, Shaun; Haas, David W.; Ritchie, Marylyn D.
Association studies have shown and continue to show a substantial amount of success in identifying links between multiple single nucleotide polymorphisms (SNPs) and phenotypes. These studies are also believed to provide insights toward identification of new drug targets and therapies. Albeit of all the success, challenges still remain for applying and prioritizing these associations based on available biological knowledge. Along with single variant association analysis, genetic interactions also play an important role in uncovering the etiology and progression of complex traits. For gene-gene interaction analysis, selection of the variants to test for associations still poses a challenge in identifying epistatic interactions among the large list of variants available in high-throughput, genome-wide datasets. Therefore in this study, we propose a pipeline to identify interactions among genetic variants that are associated with multiple phenotypes by prioritizing previously published results from main effect association analysis (genome-wide and phenome-wide association analysis) based on a-priori biological knowledge in AIDS Clinical Trials Group (ACTG) data. We approached the prioritization and filtration of variants by using the results of a previously published single variant PheWAS and then utilizing biological information from the Roadmap Epigenome project. We removed variants in low functional activity regions based on chromatin states annotation and then conducted an exhaustive pairwise interaction search using linear regression analysis. We performed this analysis in two independent pre-treatment clinical trial datasets from ACTG to allow for both discovery and replication. Using a regression framework, we observed 50,798 associations that replicate at p-value 0.01 for 26 phenotypes, among which 2,176 associations for 212 unique SNPs for fasting blood glucose phenotype reach Bonferroni significance and an additional 9,970 interactions for high
Slate, Dennis; Chipman, Richard B; Algeo, Timothy P; Mills, Samuel A; Nelson, Kathleen M; Croson, Christopher K; Dubovi, Edward J; Vercauteren, Kurt; Renshaw, Randall W; Atwood, Todd; Johnson, Shylo; Rupprecht, Charles E
In 2011, we conducted a field trial in rural West Virginia, USA to evaluate the safety and immunogenicity of a live, recombinant human adenovirus (AdRG1.3) rabies virus glycoprotein vaccine (Ontario Rabies Vaccine Bait; ONRAB) in wild raccoons (Procyon lotor) and striped skunks (Mephitis mephitis). We selected ONRAB for evaluation because of its effectiveness in raccoon rabies management in Ontario and Quebec, Canada, and significantly higher antibody prevalence rates in raccoons compared with a recombinant vaccinia-rabies glycoprotein (V-RG) vaccine, Raboral V-RG®, in US-Canada border studies. Raccoon rabies was enzootic and oral rabies vaccination (ORV) had never been used in the study area. We distributed 79,027 ONRAB baits at 75 baits/km(2) mostly by fixed-wing aircraft along parallel flight lines at 750-m intervals. Antibody prevalence was significantly higher at 49.2% (n=262) in raccoons after ONRAB was distributed than the 9.6% (n=395) before ORV. This was the highest antibody prevalence observed in raccoons by US Department of Agriculture Wildlife Services for areas with similar management histories evaluated before and after an initial ORV campaign at 75 baits/km(2) with Raboral V-RG. Tetracycline biomarker (TTCC) was significantly higher among antibody-positive raccoons after ONRAB baiting and was similar among raccoons before ORV had been conducted, an indication of vaccine-induced rabies virus-neutralizing antibody production following consumption of bait containing TTCC. Skunk sample size was inadequate to assess ONRAB effects. Safety and immunogenicity results supported replication of this field trial and led to a recommendation for expanded field trials in 2012 to evaluate safety and immunogenicity of ground-distributed ONRAB at 150 baits/km(2) in residential and commercial habitats in Ohio, USA and aerially distributed ONRAB at 75 baits/km(2) in rural habitats along US-Quebec border.
During the past 5 years, the exchange of sterile needles and syringes for dirty injecting equipment has gained increasing acceptance outside the United States as a potential means of reducing the transmission of the human immunodeficiency virus (HIV) among intravenous drug users. This article describes the controversy over attempts to establish a needle and syringe exchange scheme in New York City between 1985 and 1991. The response to a health crisis is used as an indicator of patterns of social and institutional practice. Advocates of needle exchanges had reached a stalemate with the promoters of law enforcement, and the strategic reformulation of the policy problem in terms of the research process seemed to offer a solution. The article discusses the practical limitations on designing and carrying out a controversial health promotion policy; the use (under constraint) of a restrictive research process to constitute--rather than simply to guide or monitor--public policy; and the potential ethical hazards of health professionals' seeking a polemical recourse to the clinical trial. The efforts to establish a needle exchange in New York thus illustrate more general problems for AIDS prevention. Images p1511-a p1512-a p1513-a PMID:1951815
Yoo, Byung-Kwang; Humiston, Sharon G.; Szilagyi, Peter G.; Schaffer, Stanley J.; Long, Christine; Kolasa, Maureen
School-located vaccination against influenza (SLV-I) has been suggested to help meet the need for annual vaccination of large numbers of school-aged children with seasonal influenza vaccine. However, little is known about the cost and cost-effectiveness of SLV-I. We conducted a cost-analysis and a cost-effectiveness analysis based on a randomized controlled trial (RCT) of an SLV-I program implemented in Monroe County, New York during the 2009–2010 vaccination season. We hypothesized that SLV-I is more cost effective, or less-costly, compared to a conventional, office-located influenza vaccination delivery. First and second SLV-I clinics were offered in 21 intervention elementary schools (n=9,027 children) with standard of care (no SLV-I) in 11 control schools (n=4,534 children). The direct costs, to purchase and administer vaccines, were estimated from our RCT. The effectiveness measure, receipt of ≥1 dose of influenza vaccine, was 13.2 percentage points higher in SLV-I schools than control schools. The school costs ($9.16/dose in 2009 dollars) plus project costs ($23.00/dose) plus vendor costs excluding vaccine purchase ($19.89/dose) was higher in direct costs ($52.05/dose) than the previously reported mean/median cost [$38.23/$21.44 per dose] for providing influenza vaccination in pediatric practices. However SLV-I averted parent costs to visit medical practices ($35.08 per vaccine). Combining direct and averted costs through Monte Carlo Simulation, SLV-I costs were $19.26/dose in net costs, which is below practice-based influenza vaccination costs. The incremental cost-effectiveness ratio (ICER) was estimated to be $92.50 or $38.59 (also including averted parent costs). When additionally accounting for the costs averted by disease prevention (i.e., both reduced disease transmission to household members and reduced loss of productivity from caring for a sick child), the SLV-I model appears to be cost-saving to society, compared to “no vaccination”. Our
Andrade, Regis M; Andrade, Arnaldo F B; Lazaro, Marta A; Vieira, Morgana M M; Barros, Priscila O; Borner, Alice R S; Silva-Filho, Renato G; Santos, Juliana O; Brindeiro, Rodrigo M; Tanuri, Amilcar; Bento, Cleonice A M
The purpose of this study was to evaluate the impact of age on tetanus-specific immune response in successfully highly active antiretroviral therapy-treated AIDS patients, using healthy age-matched individuals as controls. Whole Peripheral blood mononuclear cells or CD8(+) cell-depleted peripheral blood mononuclear cells from previously tetanus toxoid (TT)-immunized individuals were activated with TT plus IL-2, and cell proliferation, cytokine production, and in vitro HIV-1 replication were measured. The in vivo magnitude of the humoral immune response was also assessed by antibody measurements. Our results showed that, compared with other groups, both in vitro TT-specific lymphoproliferation and serum antibody concentration were lower in older AIDS patients. Although the IL-1beta and tumour necrosis factor alpha (TNF-alpha) production were higher in cultures from aged HIV-1-infected patients, a dramatic damage on the interferon gamma (IFN-gamma) release was observed, when compared with younger patients. CD8(+) T lymphocytes depletion reduced IL-1beta and TNF-alpha release in the older groups, however, it did not significantly alter their IFN-gamma production. Furthermore, the neutralization of endogenous IL-10 did not change the IFN-gamma deficiency in older AIDS patients. Finally, the lower cellular immune response in this patient group was not related to in vitro HIV-1 replication. The results suggest that successfully highly active antiretroviral therapy-treated aged AIDS patients do not reconstitute the immune response to TT, making them probably more susceptible to tetanus even after vaccination.
Perdiguero, Beatriz; Gómez, Carmen Elena; Cepeda, Victoria; Sánchez-Sampedro, Lucas; García-Arriaza, Juan; Mejías-Pérez, Ernesto; Jiménez, Victoria; Sánchez, Cristina; Sorzano, Carlos Óscar S.; Oliveros, Juan Carlos; Delaloye, Julie; Roger, Thierry; Calandra, Thierry; Asbach, Benedikt; Wagner, Ralf; Kibler, Karen V.; Jacobs, Bertram L.; Pantaleo, Giuseppe
ABSTRACT The generation of vaccines against HIV/AIDS able to induce long-lasting protective immunity remains a major goal in the HIV field. The modest efficacy (31.2%) against HIV infection observed in the RV144 phase III clinical trial highlighted the need for further improvement of HIV vaccine candidates, formulation, and vaccine regimen. In this study, we have generated two novel NYVAC vectors, expressing HIV-1 clade C gp140(ZM96) (NYVAC-gp140) or Gag(ZM96)-Pol-Nef(CN54) (NYVAC-Gag-Pol-Nef), and defined their virological and immunological characteristics in cultured cells and in mice. The insertion of HIV genes does not affect the replication capacity of NYVAC recombinants in primary chicken embryo fibroblast cells, HIV sequences remain stable after multiple passages, and HIV antigens are correctly expressed and released from cells, with Env as a trimer (NYVAC-gp140), while in NYVAC-Gag-Pol-Nef-infected cells Gag-induced virus-like particles (VLPs) are abundant. Electron microscopy revealed that VLPs accumulated with time at the cell surface, with no interference with NYVAC morphogenesis. Both vectors trigger specific innate responses in human cells and show an attenuation profile in immunocompromised adult BALB/c and newborn CD1 mice after intracranial inoculation. Analysis of the immune responses elicited in mice after homologous NYVAC prime/NYVAC boost immunization shows that recombinant viruses induced polyfunctional Env-specific CD4 or Gag-specific CD8 T cell responses. Antibody responses against gp140 and p17/p24 were elicited. Our findings showed important insights into virus-host cell interactions of NYVAC vectors expressing HIV antigens, with the activation of specific immune parameters which will help to unravel potential correlates of protection against HIV in human clinical trials with these vectors. IMPORTANCE We have generated two novel NYVAC-based HIV vaccine candidates expressing HIV-1 clade C trimeric soluble gp140 (ZM96) and Gag(ZM96)-Pol
Lewis, P J; Babiuk, L A
Therapeutic and prophylactic DNA vaccine clinical trials for a variety of pathogens and cancers are underway (Chattergoon et al., 1997; Taubes, 1997). The speed with which initiation of these trials occurred is no less than astounding; clinical trials for a human immunodeficiency virus (HIV) gp160 DNA-based vaccine were underway within 36 months of the first description of "genetic immunization" (Tang et al., 1992) and within 24 months of publication of the first article describing intramuscular delivery of a DNA vaccine (Ulmer et al., 1993). Despite the relative fervor with which clinical trials have progressed, it can be safely stated that DNA-based vaccines will not be an immunological "silver bullet." In this regard, it was satisfying to see a publication entitled "DNA Vaccines--A Modern Gimmick or a Boon to Vaccinology?" (Manickan et al., 1997b). There is no doubt that this technology is well beyond the phenomenology phase of study. Research niches and models have been established and will allow the truly difficult questions of mechanism and application to target species to be studied. These two aspects of future studies are intricately interwoven and will ultimately determine the necessity for mechanistic understanding and the evolution of target species studies. The basic science of DNA vaccines has yet to be clearly defined and will ultimately determine the success or failure of this technology to find a place in the immunological arsenal against disease. In a commentary on a published study describing DNA vaccine-mediated protection against heterologous challenge with HIV-1 in chimpanzees, Ronald Kennedy (1997) states, "As someone who has been in the trenches of AIDS vaccine research for over a decade and who, together with collaborators, has attempted a number of different vaccine approaches that have not panned out, I have a relatively pessimistic view of new AIDS vaccine approaches." Kennedy then goes on to summarize a DNA-based multigene vaccine
Zhang, Wei; Kong, Yujia; Jiang, Zhiwei; Li, Chanjuan; Wang, Ling; Xia, Jielai
abstract Human enterovirus 71 (EV71) is a causative agent of hand, foot, and mouth disease (HFMD). In a previous phase III trial in children, a human diploid cell-based inactivated EV71 vaccine elicited EV71 specific immune responses and protection against EV71 associated HFMD. This study aimed to assess the factors influencing the severity of adverse events observed in this previous trial. This was a randomized, double-blinded, placebo-controlled, phase III clinical trial of a human diploid vaccine carried out in 12,000 children in Guangxi Zhuang Autonomous Region, China (ClinicalTrials.gov: NCT01569581). Solicited events were recorded for 7 days and unsolicited events were reported for 28 days after each injection. Age trend analysis of adverse reaction was conducted in each treatment group. Multiple logistic regression models were built to identify factors influencing the severity of adverse reactions. Fewer solicited adverse reactions were observed in older participants within the first 7 days after vaccination (P < 0.0001), except local pain and pruritus. More severe adverse reactions were observed after the initial injection than after the booster injection. Serious cold or respiratory tract infections (RTI) were observed more often in children aged 6–36 months than in older children. Only the severity of local swelling was associated with body mass index. Children with throat discomfort before injection had a higher risk of serious cold or RTI. These results indicated that the human diploid cell-based vaccine achieved a satisfactory safety profile. PMID:26837471
Gidlund M , Chiodi F, et al.: Enhancement of human of gag genes from 70 international HIV- I isolates provides evi- immunodeficiency virus (HIV...Workshop on the Potential Risks of Antibody-Dependent Enhancement in Human HIV Vaccine Trials JOHN R. MASCOLA,’ BONNIE J. MATHIESON, 2 PHILIP M . ZACK...monocyte/macrophage ( M / M ) cells is the pathophysiological Army Institute of Research and was hosted by the Health Sciences mechanism for enhanced disease
Brezar, Vedran; Godot, Véronique; Cheng, Liang; Su, Lishan; Lévy, Yves; Seddiki, Nabila
Efficient vaccines are characterized by the establishment of long-lived memory T cells, including T-helper (effectors and follicular) and T-regulatory cells (Tregs). While the former induces cytotoxic or antibody responses, the latter regulates immune responses by maintaining homeostasis. The role of Tregs in inflammatory conditions is ambiguous and their systematic monitoring in vaccination along with effector T-cells is not instinctive. Recent studies from the cancer field clearly showed that Tregs suppress vaccine-induced immune responses and correlate with poor clinical benefit. In HIV infection, Tregs are needed during acute infection to preserve tissue integrity from an overwhelmed activation, but are not beneficial in chronic infection as they suppress anti-HIV responses. Current assays used to evaluate vaccine-induced specific responses are limited as they do not take into account antigen-specific Tregs. However, new assays, such as the OX40 assay, which allow for the simultaneous detection of a full range of Th-responses including antigen-specific Tregs responses, can overcome these issues. In this review article we will revise the role of Tregs in vaccination and review the recent work performed in the field, including the available tools to monitor them, from novel assays to humanized mouse models.
Riedmann, Eva M
Infant rotavirus vaccination provides for herd immunity Nonreplicating sporozoite vaccine protects humans against malaria Personalized brain cancer vaccine enters phase 2 trial Novel implantable therapeutic cancer vaccine to be tested in humans Clostridium difficile vaccine candidate successful in phase 1 CDC reports strong uptake of HPV vaccine in boys Whooping cough outbreak in Texas.
Tsang, Peter; Gorse, Geoffrey J; Strout, Cynthia B; Sperling, Malcolm; Greenberg, David P; Ozol-Godfrey, Ayca; DiazGranados, Carlos; Landolfi, Victoria
We conducted a randomized, controlled, multicenter, phase II study to evaluate the immunogenicity and safety of an investigational intradermal (ID) trivalent influenza vaccine (TIV) and a high-dose (HD) intramuscular (IM) TIV in older adults (≥65 years of age). Older adult subjects were immunized with ID vaccine containing either 15μg hemagglutinin (HA)/strain (n=636) or 21μg HA/strain (n=634), with HD IM vaccine containing 60μg HA/strain (n=320), or with standard-dose (SD) IM vaccine (Fluzone(®); 15μg HA/strain; n=319). For comparison, younger adults (18-49 years of age) were immunized with SD IM vaccine. In older adults, post-vaccination geometric mean titers induced by the ID vaccines were superior to those induced by the SD IM vaccine for the A/H1N1 and A/H3N2 strains and non-inferior for the B strain. Seroconversion rates induced by the ID vaccines were superior to those induced by the SD IM vaccine in older adults for the A/H1N1 and B strains and non-inferior for the A/H3N2 strain. Results did not differ significantly for the two ID vaccine dosages. Post-vaccination geometric mean titers, seroconversion rates, and most seroprotection rates were significantly higher in HD vaccine recipients than in older adult recipients of the SD IM or ID vaccines and, for most measures, were comparable to those of younger adult SD IM vaccine recipients. Injection-site reactions, but not systemic reactions or unsolicited adverse events, were more common with the ID vaccines than with the IM vaccines. No treatment-related serious adverse events were reported. This study demonstrated that: (1) the ID and HD vaccines were well-tolerated and more immunogenic than the SD IM vaccine in older adults; (2) the HD vaccine was more immunogenic than the ID vaccines in older adults; and (3) the HD vaccine in older adults and the SD IM vaccine in younger adults elicited comparable antibody responses (ClinicalTrials.gov identifier no.: NCT00551031).
Gullsby, Karolina; Hallander, Hans O; Bondeson, Kåre
A real-time PCR method targeting the Bordetella pertussis IS481 gene fragment was evaluated in a vaccine trial setting in which real-time PCR results could be validated against culture and serology results. Two commonly used DNA extraction methods, Amplicor Respiratory Preparation kit and the QIAamp DNA Mini Kit, were compared. An approximately 50-fold higher sensitivity was achieved using the Amplicor kit. 89 of 276 aspirates analysed with the IS481 real-time PCR were positive. Interestingly, six of these were culture negative and came from serology-negative patients. Defining true positive cases either as culture-positive or as PCR-positive cases that had been confirmed with a serology-positive result or verified with a newly constructed recA PCR, the sensitivity and specificity of the IS481 real-time PCR were 89% and 98%, respectively. This study confirms the specificity and high diagnostic sensitivity of IS481-based PCR methods for diagnosis of B. pertussis.
Recommended infant vaccination in Korea includes DTaP-IPV and Hib vaccines administered as separate injections. In this randomized, open, controlled study we assessed the non-inferiority of immunogenicity of DTaP-IPV//Hib pentavalent combination vaccine (Pentaxim™) compared with licensed DTaP-IPV and Hib (PRP~T) vaccines. We enrolled 418 healthy Korean infants to receive either separate DTaP-IPV and Hib vaccines (n = 206) or the pentavalent DTaP-IPV//Hib (n = 208) vaccine at 2, 4, 6 months of age. Antibodies to all components were measured before the first vaccination and one month after the third, and safety was assessed after each vaccination including recording of reactions by parents. We confirmed the non-inferiority of DTaP-IPV//Hib compared with DTaP-IPV and Hib vaccines; 100% of both groups achieved seroprotection against D, T, IPV and PRP~T, and 97.5%–99.0% demonstrated seroresponses to pertussis antigens. Antibody levels were similar in both groups, except for those to the Hib component, PRP~T. In separate and combined groups geometric mean concentrations of anti-PRP~T antibodies were 23.9 and 11.0 µg/mL, respectively, but 98.3% and 97.4% had titers ≥ 1 µg/mL, indicative of long-term protection. All vaccines were well tolerated, with no vaccine-related serious adverse event. Both groups had similar safety profiles, but the combined vaccine group had fewer injection site reactions. The immunological non-inferiority and similar safety profile of DTaP-IPV//Hib vaccine to separate DTaP-IPV and Hib vaccines, with the advantage of fewer injections and injection site reactions, supports the licensure and incorporation of DTaP-IPV//Hib into the Korean national vaccination schedule (Clinical trial registry, NCT01214889). PMID:27510380
Samir, Parimal; Galassie, Allison; Allos, Tara M.; Niu, Xinnan; Gordy, Laura E.; Creech, C. Buddy; Prasad, Nripesh; Jensen, Travis L.; Hill, Heather; Levy, Shawn E.; Joyce, Sebastian; Link, Andrew J.; Edwards, Kathryn M.
Background Vaccine development for influenza A/H5N1 is an important public health priority, but H5N1 vaccines are less immunogenic than seasonal influenza vaccines. Adjuvant System 03 (AS03) markedly enhances immune responses to H5N1 vaccine antigens, but the underlying molecular mechanisms are incompletely understood. Objective and Methods We compared the safety (primary endpoint), immunogenicity (secondary), gene expression (tertiary) and cytokine responses (exploratory) between AS03-adjuvanted and unadjuvanted inactivated split-virus H5N1 influenza vaccines. In a double-blinded clinical trial, we randomized twenty adults aged 18–49 to receive two doses of either AS03-adjuvanted (n = 10) or unadjuvanted (n = 10) H5N1 vaccine 28 days apart. We used a systems biology approach to characterize and correlate changes in serum cytokines, antibody titers, and gene expression levels in six immune cell types at 1, 3, 7, and 28 days after the first vaccination. Results Both vaccines were well-tolerated. Nine of 10 subjects in the adjuvanted group and 0/10 in the unadjuvanted group exhibited seroprotection (hemagglutination inhibition antibody titer > 1:40) at day 56. Within 24 hours of AS03-adjuvanted vaccination, increased serum levels of IL-6 and IP-10 were noted. Interferon signaling and antigen processing and presentation-related gene responses were induced in dendritic cells, monocytes, and neutrophils. Upregulation of MHC class II antigen presentation-related genes was seen in neutrophils. Three days after AS03-adjuvanted vaccine, upregulation of genes involved in cell cycle and division was detected in NK cells and correlated with serum levels of IP-10. Early upregulation of interferon signaling-related genes was also found to predict seroprotection 56 days after first vaccination. Conclusions Using this cell-based systems approach, novel mechanisms of action for AS03-adjuvanted pandemic influenza vaccination were observed. Trial Registration ClinicalTrials.gov NCT
Gilbert, Peter B.; Sun, Yanqing
This article develops hypothesis testing procedures for the stratified mark-specific proportional hazards model in the presence of missing marks. The motivating application is preventive HIV vaccine efficacy trials, where the mark is the genetic distance of an infecting HIV sequence to an HIV sequence represented inside the vaccine. The test statistics are constructed based on two-stage efficient estimators, which utilize auxiliary predictors of the missing marks. The asymptotic properties and finite-sample performances of the testing procedures are investigated, demonstrating double-robustness and effectiveness of the predictive auxiliaries to recover efficiency. The methods are applied to the RV144 vaccine trial. PMID:25641990
Durviaux, Serge; Treanor, John; Beran, Jiri; Duval, Xavier; Esen, Meral; Feldman, Gregory; Frey, Sharon E.; Launay, Odile; Leroux-Roels, Geert; McElhaney, Janet E.; Nowakowski, Andrzej; Ruiz-Palacios, Guillermo M.; van Essen, Gerrit A.; Oostvogels, Lidia; Devaster, Jeanne-Marie
Estimations of the effectiveness of vaccines against seasonal influenza virus are guided by comparisons of the antigenicities between influenza virus isolates from clinical breakthrough cases with strains included in a vaccine. This study examined whether the prediction of antigenicity using a sequence analysis of the hemagglutinin (HA) gene-encoded HA1 domain is a simpler alternative to using the conventional hemagglutination inhibition (HI) assay, which requires influenza virus culturing. Specimens were taken from breakthrough cases that occurred in a trivalent influenza virus vaccine efficacy trial involving >43,000 participants during the 2008-2009 season. A total of 498 influenza viruses were successfully subtyped as A(H3N2) (380 viruses), A(H1N1) (29 viruses), B(Yamagata) (23 viruses), and B(Victoria) (66 viruses) from 603 PCR- or culture-confirmed specimens. Unlike the B strains, most A(H3N2) (377 viruses) and all A(H1N1) viruses were classified as homologous to the respective vaccine strains based on their HA1 domain nucleic acid sequence. HI titers relative to the respective vaccine strains and PCR subtyping were determined for 48% (182/380) of A(H3N2) and 86% (25/29) of A(H1N1) viruses. Eighty-four percent of the A(H3N2) and A(H1N1) viruses classified as homologous by sequence were matched to the respective vaccine strains by HI testing. However, these homologous A(H3N2) and A(H1N1) viruses displayed a wide range of relative HI titers. Therefore, although PCR is a sensitive diagnostic method for confirming influenza virus cases, HA1 sequence analysis appeared to be of limited value in accurately predicting antigenicity; hence, it may be inappropriate to classify clinical specimens as homologous or heterologous to the vaccine strain for estimating vaccine efficacy in a prospective clinical trial. PMID:24371255
Cornejo-Juárez, Patricia; Volkow-Fernández, Patricia; Escobedo-López, Kenia; Vilar-Compte, Diana; Ruiz-Palacios, Guillermo; Soto-Ramírez, Luis Enrique
Background Co-infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is not infrequent as both share same route of exposure. The risk of developing chronic hepatitis B virus is 6%, in general population but can reach 10–20% in HBV/HIV co-infected patients. When compared to general population, the response rate to HBV vaccine in HIV-infected patients is diminished, so previous studies have tried to improve this response using variety of schedules, doses and co-administration of immunomodulators. The purpose of this study was to evaluate two doses of recombinant HBV vaccine (10 or 40 μg), IM at 0, 1 and 6 months. Vaccination response was measured 30–50 days after last dose; titers of >9.9 IU/L were considered positive. Results Seventy-nine patients were included, 48 patients (60.7%) serconverted. Thirty-nine patients (49.3%) received 10 μg vaccine dose, 24 patients (61.5%) seroconverted. Forty patients (50.7%) received 40 μg vaccine dose, 24 (60%) seroconverted. There were no differences between two doses. A statistically significant higher seroconversion rate was found for patients with CD4 cell counts at vaccination ≥ 200 cel/mm3 (33 of 38 patients, 86.8%), compared with those with CD4 < 200 cel/mm3 (15 of 41, 36.6%), [OR 11.44, 95% IC 3.67–35.59, p = 0.003], there were no differences between two vaccine doses. Using the logistic regression model, CD4 count <200 cel/mm3 were significantly associated with non serologic response (p = 0.003). None other variables such as gender, age, risk exposure for HIV, viral load, type or duration of HAART or AIDS-defining illness, were asociated with seroconversion. Conclusion In this study, an increase dose of HBV vaccine did not show to increase the rate of response in HIV infected subjects. The only significant findings associated to the response rate was that a CD4 count ≥ 200 cel/mm3, we suggest this threshold at which HIV patients should be vaccinated. PMID:16600028
Pittman, Phillip R.; Norris, Sarah L.; Brown, Elizabeth S.; Ranadive, Manmohan V.; Schibly, Barbara A.; Bettinger, George E.; Lokugamage, Nandadeva; Korman, Lawrence; Morrill, John C.; Peters, Clarence J.
An outbreak or deliberate release of Rift Valley fever (RVF) virus could have serious public health and socioeconomic consequences. A safe RVF vaccine capable of eliciting long-lasting immunity after a single injection is urgently needed. The live attenuated RVF MP-12 vaccine candidate has shown promise in Phase 1 clinical trials; no evidence of reversion to virulence has been identified in numerous animal studies. The objective of this Phase 2 clinical trial was to (a) further examine the safety and immunogenicity of RVF MP-12 in RVF virus–naïve humans and (b) characterize isolates of RVF MP-12 virus recovered from the blood of vaccinated subjects to evaluate the genetic stability of MP-12 attenuation. We found that RVF MP-12 was well tolerated, causing mostly mild reactions that resolved without sequelae. Of 19 subjects, 18 (95%) and 19 (100%) achieved, respectively, 80% and 50% plaque reduction neutralization titers (PRNT80 and PRNT50) ≥ 1:20 by postvaccination day 28. All 18 PRNT80 responders maintained PRNT80 and PRNT50 ≥ 1:40 until at least postvaccination month 12. Viremia was undetectable in the plasma of any subject by direct plaque assay techniques. However, 5 of 19 vaccinees were positive for MP-12 isolates in plasma by blind passage of plasma on Vero cells. Vaccine virus was also recovered from buffy coat material from one of those vaccinees and from one additional vaccinee. Through RNA sequencing of MP-12 isolates, we found no reversions of amino acids to those of the parent virulent virus (strain ZH548). Five years after a single dose of RVF MP-12 vaccine, 8 of 9 vaccinees (89%) maintained a PRNT80 ≥ 1:20. These findings support the continued development of RVF MP-12 as a countermeasure against RVF virus in humans. PMID:26706271
Zaman, K; Yunus, M; El Arifeen, Shams; Azim, Tasnim; Faruque, A S G; Huq, Ehsanul; Hossain, Ilias; Luby, Stephen P; Victor, John C; Dallas, Michael J; Lewis, Kristen D C; Rivers, Stephen B; Steele, A Duncan; Neuzil, Kathleen M; Ciarlet, Max; Sack, David A
An efficacy clinical trial with pentavalent rotavirus vaccine (PRV), RotaTeq(®), was conducted at Matlab field site of ICDDR,B, Bangladesh from March 2007 to March 2009. The methodology, including operation logistics, and lessons-learned are described in this report. Vaccination was organized at 41 fixed-site clinics twice/month. A total of 1136 infants were randomized 1:1 to receive 3 doses of PRV/placebo at approximately 6-, 10-, and 14-weeks of age with routine vaccines of the Expanded Programme on Immunization (EPI) schedule. Twelve field-workers routinely visited study participants for safety and efficacy follow-up. The study was conducted following good clinical practices and maintaining cold-chain requirements. There were no temperature deviations of clinical vaccine supplies. Data entry was done using the source documents to a central database developed by the sponsor which was linked to web. Among enrolled infants, 1128 (99.3%) received 3 doses of PRV/placebo and efficacy follow-up was conducted for a median of 554 days. For the evaluation of immunogenicity, blood samples were collected from 150 participants predose 1 and from 147 (98%) of the same participants post dose 3. Stool samples were collected from 778 (99.9%) acute gastroenteritis episodes among children who reported to diarrhoea treatment centres. Thirty-nine serious adverse events, including 6 deaths, occurred among study participants. The efficacy of PRV against severe rotavirus gastroenteritis was 42.7% through the entire follow-up period; serum anti-rotavirus IgA response was 78.1%. Inclement weather, difficult transportation, and movement of study participants were some of the challenges identified. This is the first vaccine trial in rural Bangladesh with online data entry. The study was well accepted in the community and was completed successfully.
Pittman, Phillip R; Norris, Sarah L; Brown, Elizabeth S; Ranadive, Manmohan V; Schibly, Barbara A; Bettinger, George E; Lokugamage, Nandadeva; Korman, Lawrence; Morrill, John C; Peters, Clarence J
An outbreak or deliberate release of Rift Valley fever (RVF) virus could have serious public health and socioeconomic consequences. A safe RVF vaccine capable of eliciting long-lasting immunity after a single injection is urgently needed. The live attenuated RVF MP-12 vaccine candidate has shown promise in Phase 1 clinical trials; no evidence of reversion to virulence has been identified in numerous animal studies. The objective of this Phase 2 clinical trial was to (a) further examine the safety and immunogenicity of RVF MP-12 in RVF virus-naïve humans and (b) characterize isolates of RVF MP-12 virus recovered from the blood of vaccinated subjects to evaluate the genetic stability of MP-12 attenuation. We found that RVF MP-12 was well tolerated, causing mostly mild reactions that resolved without sequelae. Of 19 subjects, 18 (95%) and 19 (100%) achieved, respectively, 80% and 50% plaque reduction neutralization titers (PRNT80 and PRNT50)≥1:20 by postvaccination day 28. All 18 PRNT80 responders maintained PRNT80 and PRNT50≥1:40 until at least postvaccination month 12. Viremia was undetectable in the plasma of any subject by direct plaque assay techniques. However, 5 of 19 vaccinees were positive for MP-12 isolates in plasma by blind passage of plasma on Vero cells. Vaccine virus was also recovered from buffy coat material from one of those vaccinees and from one additional vaccinee. Through RNA sequencing of MP-12 isolates, we found no reversions of amino acids to those of the parent virulent virus (strain ZH548). Five years after a single dose of RVF MP-12 vaccine, 8 of 9 vaccinees (89%) maintained a PRNT80≥1:20. These findings support the continued development of RVF MP-12 as a countermeasure against RVF virus in humans.
Brown, B; Blas, M M; Heidari, O; Carcamo, C; Halsey, N A
Limited data exist on the effect of clinical trial participation on sexual behavioural change. Two hundred female sex workers working in Lima, Peru received human papillomavirus (HPV) vaccine in either the standard (0, 2, 6 months) or modified (0, 3, 6 months) schedule. Participants received comprehensive screening and treatment for sexually transmitted infections (STIs), counselling on safe sex practices, education about HPV and the HPV vaccine, contraceptives (oral and condoms) and family planning at each visit. We assessed vaccine completion rates, change in sexual practices, and changes in HPV knowledge before and after participation in the vaccine trial. There were high rates of vaccine completion, 91% overall. The estimated number of reported new and total clients over a 30-day period decreased significantly (P < 0.001). Knowledge about HPV and HPV-related disease increased among all participants. In addition, all participants listed at least one preventive strategy during the month 7 follow-up survey.
58.2. (1) A major limitation is the amino acid variability of the V3 epitope. Although most of the V3 sequence is hypervariable, the neutralizing...epitope at the "tip" of the loop, GPGRAF, is present in about 60% of North American Clade B isolates. 4 The "tip" sequence , GPGRAF, is conserved to a much...tropic strains do not, the MT strains are important vaccine targets. The conserved "tip" sequence in MT strains is thus an attractive target. Its
Sheets, Rebecca L.; Rangavajhula, Vijaya; Pullen, Jeffrey K.; Butler, Chris; Mehra, Vijay; Shapiro, Stuart
The Division of AIDS Vaccine Research Program funds the discovery and development of HIV/AIDS vaccine candidates. Basic researchers, having discovered a potential vaccine in the laboratory, next want to take that candidate into the clinic to test the concept in humans, to see if it translates. Many of them have heard of “cGMP” and know that they are supposed to make a “GMP product” to take into the clinic, but often they are not very familiar with what “cGMP” means and why these good practices are so important. As members of the Vaccine Translational Research Branch, we frequently get asked “can’t we use the material we made in the lab in the clinic?” or “aren’t Phase 1 studies exempt from cGMP?” Over the years, we have had many experiences where researchers or their selected contract manufacturing organizations have not applied an appropriate degree of compliance with cGMP suitable for the clinical phase of development. We share some of these experiences and the lessons learned, along with explaining the importance of cGMP, just what cGMP means, and what they can assure, in an effort to de-mystify this subject and facilitate the rapid and safe translational development of HIV vaccines. PMID:25698494
Aaby, Peter; Andersen, Andreas; Martins, Cesário L; Fisker, Ane B; Rodrigues, Amabelia; Whittle, Hilton C; Benn, Christine S
Background BCG and measles vaccine (MV) may have beneficial non-specific effects (NSEs). If an unplanned intervention with a vaccine (a natural experiment) modifies the estimated effect in a randomised controlled trial (RCT), this suggests NSEs. We used this approach to test NSEs of triple oral polio vaccine (OPV). Methods During an RCT of 2 doses of MV at 4.5 and 9 months versus 1 dose of MV at 9 months of age, we experienced 2 natural experiments with OPV. We assessed whether these OPV experiments modified the effect of 2-dose MV in the MV trial. Setting MV RCT conducted in urban Guinea-Bissau 2003–2009. Interventions Natural experiments with OPV due to missing vaccine and the implementation of OPV campaigns. Main outcome measure Changes in the mortality rate ratio (MRR) for 2-dose MV versus 1-dose MV. Results First, the MRR (2-dose/1-dose MV) overall was 0.70 (0.52 to 0.94), but the MRR was 1.04 (0.53 to 2.04) when OPV at birth (OPV0) was not given, suggesting that early priming with OPV was important for the effect of 2-dose MV. The effect of OPV0 depended on age of administration; the MRR (2-dose/1-dose MV) was 0.45 (0.29 to 0.71) for children receiving OPV0 in the first week of life, but 3.63 (0.87 to 15.2) for those receiving OPV0 after the first month of life (p=0.007, test of no interaction). Second, campaign-OPV may have reduced the difference between the randomisation groups since the MRR (2-dose/1-dose MV) was 0.60 (0.42 to 0.85) for children who had not received campaign-OPV before RCT-enrolment versus 0.72 (0.23 to 2.31) and 1.42 (0.70 to 2.90) for children who had received 1 or 2 doses of campaign-OPV-before-enrolment, respectively. Conclusions Bissau had no polio infection during this trial, so OPV0 and campaign-OPV may have NSEs since they modified the effect of 2-dose MV in an RCT. Different interventions may interact to a much larger effect than usually assumed. PMID:28011813
Brandreth, Marian; Brassington, William; Leighton, Paul; Wharrad, Heather
Objectives: The aims of this study were to (1) develop a series of short interactive videos (or reusable learning objects [RLOs]) covering a broad range of practical and psychosocial issues relevant to the auditory rehabilitation for first-time hearing aid users; (2) establish the accessibility, take-up, acceptability and adherence of the RLOs; and (3) assess the benefits and cost-effectiveness of the RLOs. Design: The study was a single-center, prospective, randomized controlled trial with two arms. The intervention group (RLO+, n = 103) received the RLOs plus standard clinical service including hearing aid(s) and counseling, and the waitlist control group (RLO−, n = 100) received standard clinical service only. The effectiveness of the RLOs was assessed 6-weeks posthearing aid fitting. Seven RLOs (total duration 1 hr) were developed using a participatory, community of practice approach involving hearing aid users and audiologists. RLOs included video clips, illustrations, animations, photos, sounds and testimonials, and all were subtitled. RLOs were delivered through DVD for TV (50.6%) and PC (15.2%), or via the internet (32.9%). Results: RLO take-up was 78%. Adherence overall was at least 67%, and 97% in those who attended the 6-week follow-up. Half the participants watched the RLOs two or more times, suggesting self-management of their hearing loss, hearing aids, and communication. The RLOs were rated as highly useful and the majority of participants agreed the RLOs were enjoyable, improved their confidence and were preferable to written information. Postfitting, there was no significant between-group difference in the primary outcome measure, overall hearing aid use. However, there was significantly greater hearing aid use in the RLO+ group for suboptimal users. Furthermore, the RLO+ group had significantly better knowledge of practical and psychosocial issues, and significantly better practical hearing aid skills than the RLO− group. Conclusions: The RLOs
Mahmoudi, Shima; Keshavarz, Hossein
Although vaccines would be the ideal tool for control, prevention, elimination, and eradication of many infectious diseases, developing of parasites vaccines such as malaria vaccine is very complex. The most advanced malaria vaccine candidate is RTS,S, a pre-erythrocytic vaccine for which pivotal phase III trial design is underway. Few recent malaria vaccine review articles have attempted to outline of all clinical trials that have occurred globally and no meta-analysis was performed on efficacy of Phase 3 Trial of RTS, S/AS01 Malaria vaccine up to now in infants. Therefore, a systematic review and meta-analysis was carried out to review new and existing data on efficacy of Phase 3 Trial of RTS, S/AS01 Malaria Vaccine in infants. The electronic databases searched were Pubmed (1965-present) and Web of Science (1970-present) (Search date: May, 2016). After full-text review of the papers evaluating clinical/severe malaria in several well-designed phase III field efficacy trials, 5 were determined to meet the eligibility criteria for inclusion in the systematic review. Four out of the 5 publications dealing with efficacy of Phase 3 Trial of RTS, S/AS01 malaria vaccine were included in the qualitative analysis. Pooled estimate of vaccine efficacy in clinical and severe malaria in children aged 5-17 mo was 29% (95% CL: 19%-46%) and 39% (95% CI 20%-74%), while this estimate vaccine in clinical and severe malaria in children aged 6-12 mo was 19% (95% CI 14%-24%) and 21 (95% CI 19%-37%), respectively. On the other hand, higher VE was seen in both per- protocol and intention-to-treat population in children aged 5-17 than the children aged 6-12 mo. The results of this meta-analysis suggest that this candidate malaria vaccine has relatively little efficacy, and the vaccine apparently will not meet the goal of malaria eradication by itself.
Two consecutive randomized controlled pertussis booster trials in children initially vaccinated in infancy with an acellular vaccine: The first with a five-component Tdap vaccine to 5-year olds and the second with five- or monocomponent Tdap vaccines at age 14-15 years.
Carlsson, R M; Gustafsson, L; Hallander, H O; Ljungman, M; Olin, P; Gothefors, L; Nilsson, L; Netterlid, E
Prior study children from a DTaP efficacy trial were recruited at ages 5 and 15 years to randomized booster trials addressing immunogenicity and reactogenicity; 475 preschool children received mixed or separate injections of a reduced antigen vaccine (Tdap5, Sanofi Pasteur MSD) and an inactivated polio vaccine, and 230 adolescents received the same or another booster vaccine (Tdap1, SSI, Denmark). Pre-vaccination antibody concentrations against pertussis antigens were significantly higher at 15 than 5 years of age, probably due to natural boosting between the studies. Tdap5 induced comparable anti-PT concentrations at both ages, but antibody responses were significantly higher to filamentous haemagglutinin, pertactin and fimbriae 2/3 in adolescents. As expected, a higher amount of PT (Tdap1, 20μg) induced a stronger anti-PT response than a lower amount (Tdap5, 2.5μg). The frequency of adverse events was low and there were no serious adverse reactions. All local reactions had an early onset and a short duration. A large swelling or redness of more than half of the upper arm circumference was reported in 8/475 5-year-olds and in 6/230 15-year-olds. Children vaccinated with Tdap5 reported more moderate pain in adolescence than at preschool age, whereas itching was only reported in preschool children. Sweden introduced DTaP vaccines in 1996 after a 17-year hiatus with no general pertussis vaccination and pertussis was still endemic at the time of the studies. The frequency of adverse events was nevertheless low in both preschool children and adolescents and antibody responses were adequate. These studies document immunogenicity and reactogenicity in a trial cohort consecutively vaccinated with acellular pertussis vaccines from infancy to adolescence. The adolescent study was registered at ClinicalTrials.gov on 26 March 2009 (NCT00870350).
Eden, Karen B.; Perrin, Nancy A.; Hanson, Ginger C.; Messing, Jill T.; Bloom, Tina L.; Campbell, Jacquelyn C.; Gielen, Andrea C.; Clough, Amber S.; Barnes-Hoyt, Jamie S.; Glass, Nancy E.
Background An Internet safety decision aid was developed to help abused women understand their risk for repeat and near-lethal intimate partner violence, clarify priorities related to safety, and develop an action plan customized to these priorities. Purpose The overall purpose of this study was to test the effectiveness of a safety decision aid compared with usual safety planning (control) delivered through a secure website, using a multi-state randomized controlled trial design. The paper evaluated the effectiveness of the safety decision aid in reducing decisional conflict after a single use by abused women. Design Randomized controlled trial referred to as IRIS, Internet Resource for Intervention and Safety Participants Abused women who spoke English (N = 708) were enrolled in a four-state, randomized controlled trial. Intervention and Control The intervention was an interactive safety decision aid with personalized safety plan; the control condition was usual safety planning resources. Both were delivered to participants through the secure study website. Main Outcome Measures This paper compared women’s decisional conflict about safety: total decisional conflict and the four subscales of this measure (feeling: uninformed, uncertain, unclear about safety priorities; and sensing lack of support) between intervention/control conditions. Data were collected 3/2011–5/2013 and analyzed 1/2014–3/2014. Results Immediately following the first use of the interactive safety decision aid, intervention women had significantly lower total decisional conflict than control women, controlling for baseline value of decisional conflict (p=0.002, effect size=.12). After controlling for baseline values, the safety decision aid group had significantly greater reduction in feeling uncertain (p=0.006, effect size=.07), and in feeling unsupported (p=0.008, effect size=.07) about safety than the usual safety planning group. Conclusions Abused women randomized to the safety
Gazzinelli, Maria Flavia; Lobato, Lucas; Matoso, Leonardo; Avila, Renato; de Cassia Marques, Rita; Shah Brown, Ami; Correa-Oliveira, Rodrigo; Bethony, Jeffrey M.; Diemert, David J.
Background Obtaining informed consent for clinical trials is especially challenging when working in rural, resource-limited areas, where there are often high levels of illiteracy and lack of experience with clinical research. Such an area, a remote field site in the northeastern part of the state of Minas Gerais, Brazil, is currently being prepared for clinical trials of experimental hookworm vaccines. This study was conducted to assess whether special educational tools can be developed to increase the knowledge and comprehension of potential clinical trial participants and thereby enable them to make truly informed decisions to participate in such research. Methodology/Principal Findings An informational video was produced to explain the work of the research team and the first planned hookworm vaccine trial, using a pedagogical method based on analogies. Seventy-two adults living in a rural community of Minas Gerais were administered a structured questionnaire that assessed their knowledge of hookworm, of research and of the planned hookworm vaccine trial, as well as their attitudes and perceptions about the researchers and participation in future vaccine trials. The questionnaire was administered before being shown the educational video and two months after and the results compared. After viewing the video, significant improvements in knowledge related to hookworm infection and its health impact were observed: using a composite score combining related questions for which correct answers were assigned a value of 1 and incorrect answers a value of 0, participants had a mean score of 0.76 post-video compared to 0.68 pre-video (p = 0.0001). Similar improvements were seen in understanding the purpose of vaccination and the possible adverse effects of an experimental vaccine. Although 100% of participants expressed a positive opinion of the researchers even before viewing the film and over 90% said that they would participate in a hookworm vaccine trial, an
Greenberg, Richard N.; Hay, Christine M.; Stapleton, Jack T.; Marbury, Thomas C.; Wagner, Eva; Kreitmeir, Eva; von Krempelhuber, Alfred; Young, Philip; Nichols, Richard; Meyer, Thomas P.; Weigl, Josef; Virgin, Garth; Arndtz-Wiedemann, Nathaly; Chaplin, Paul
Background Modified Vaccinia Ankara MVA-BN® is a live, highly attenuated, viral vaccine under advanced development as a non-replicating smallpox vaccine. In this Phase II trial, the safety and immunogenicity of Modified Vaccinia Ankara MVA-BN® (MVA) was assessed in a 56–80 years old population. Methods MVA with a virus titer of 1 x 108 TCID50/dose was administered via subcutaneous injection to 56–80 year old vaccinia-experienced subjects (N = 120). Subjects received either two injections of MVA (MM group) or one injection of Placebo and one injection of MVA (PM group) four weeks apart. Safety was evaluated by assessment of adverse events (AE), focused physical exams, electrocardiogram recordings and safety laboratories. Solicited AEs consisted of a set of pre-defined expected local reactions (erythema, swelling, pain, pruritus, and induration) and systemic symptoms (body temperature, headache, myalgia, nausea and fatigue) and were recorded on a memory aid for an 8-day period following each injection. The immunogenicity of the vaccine was evaluated in terms of humoral immune responses measured with a vaccinia-specific enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization test (PRNT) before and at different time points after vaccination. Results Vaccinations were well tolerated by all subjects. No serious adverse event related to MVA and no case of myopericarditis was reported. The overall incidence of unsolicited AEs was similar in both groups. For both groups immunogenicity responses two weeks after the final vaccination (i.e. Visit 4) were as follows: Seroconversion (SC) rates (doubling of titers from baseline) in vaccine specific antibody titers measured by ELISA were 83.3% in Group MM and 82.8% in Group PM (difference 0.6% with 95% exact CI [-13.8%, 15.0%]), and 90.0% for Group MM and 77.6% for Group PM measured by PRNT (difference 12.4% with 95% CI of [-1.1%, 27.0%]). Geometric mean titers (GMT) measured by ELISA two weeks after
Malnutrition levels among vaccinated and unvaccinated children between 2 and 3 years of age following enrollment in a randomized clinical trial with the pentavalent rotavirus vaccine (PRV) in Bangladesh.
Feller, Andrea J; Zaman, K; Lewis, Kristen D C; Hossain, Ilias; Yunus, M; Sack, David A
A double-masked, individually randomized Phase 3 clinical trial to assess the efficacy, safety and immunogenicity of the pentavalent rotavirus vaccine (PRV), RotaTeq™, was conducted in rural Matlab, Bangladesh (NCT00362648). A total of 1136 infants were enrolled and randomized to receive either vaccine or placebo in a 1:1 ratio administered with the standard EPI vaccines at a mean age of approximately 8, 12, and 16 weeks. Weight was collected at four time points (study vaccine doses 1, 2, and 3, and a close-out visit in March 2009 at 15-26 months of age), and birth weight was retrospectively collected from information contained on the mother's health card when available. Approximately one year following trial completion a separate study was conducted to collect anthropometry measurements, including weight and height. These measurements were linked with Phase 3 trial data and a post hoc analysis was conducted to assess the effects of rotavirus vaccination on malnutrition among enrolled children who could be located when they were between 27 and 38 months old. Among the 1033 (91%) children located, and measured, for this analysis height-for-age and weight-for-height Z scores were calculated and compared between vaccine and placebo recipients at the anthropometry follow-up 1-year post-trial, and weight-for-age Z scores were calculated at four trial time points in addition to the anthropometry follow-up. The data indicated that there was no effect of rotavirus vaccination on malnutrition in this population at any of the measured time points. PRV, estimated to have about 43% efficacy against severe rotavirus gastroenteritis in this population, may not reduce the overall burden of diarrheal illness sufficiently among all vaccinees to appreciably measure impact on growth compared with non-vaccinees. Regardless of the impact on malnutrition indicators, rotavirus vaccines are an important intervention for reducing morbidity and mortality in children in developing
Report on the first WHO integrated meeting on development and clinical trials of influenza vaccines that induce broadly protective and long-lasting immune responses: Hong Kong SAR, China, 24-26 January 2013.
Girard, Marc P; Tam, John S; Pervikov, Yuri; Katz, Jacqueline M
On January 24-26, 2013, the World Health Organization convened the first integrated meeting on "The development and clinical trials of vaccines that induce broadly protective and long-lasting immune responses" to review the current status of development and clinical evaluation of novel influenza vaccines as well as strategies to produce and deliver vaccines in novel ways. Special attention was given to the development of possible universal influenza vaccines. Other topics that were addressed included an update on clinical trials of pandemic and seasonal influenza vaccines in high-risk groups and vaccine safety, as well as regulatory issues.
Murahashi, Mutsunori; Hijikata, Yasuki; Yamada, Kazunari; Tanaka, Yoshihiro; Kishimoto, Junji; Inoue, Hiroyuki; Marumoto, Tomotoshi; Takahashi, Atsushi; Okazaki, Toshihiko; Takeda, Kazuyoshi; Hirakawa, Masakazu; Fujii, Hiroshi; Okano, Shinji; Morita, Masaru; Baba, Eishi; Mizumoto, Kazuhiro; Maehara, Yoshihiko; Tanaka, Masao; Akashi, Koichi; Nakanishi, Yoichi; Yoshida, Koji; Tsunoda, Takuya; Tamura, Kazuo; Nakamura, Yusuke; Tani, Kenzaburo
We designed a phase I trial to investigate the safety, immune responses and clinical benefits of a five-peptide cancer vaccine in combination with chemotherapy. Study subjects were patients positive for HLA-A2402 with locally advanced, metastatic, and/or recurrent gastrointestinal, lung or cervical cancer. Eighteen patients including nine cases of colorectal cancer were treated with escalating doses of cyclophosphamide 4days before vaccination. Five HLA-A2402-restricted, tumor-associated antigen (TAA) epitope peptides from KOC1, TTK, URLC10, DEPDC1 and MPHOSPH1 were injected weekly for 4weeks. Treatment was well tolerated without any adverse events above grade 3. Analysis of peripheral blood lymphocytes showed that the number of regulatory T cells dropped from baseline after administration of cyclophosphamide and confirmed that TAA-specific T cell responses were associated significantly with longer overall survival. This phase I clinical trial demonstrated safety and promising immune responses that correlated with vaccine-induced T-cell responses. Therefore, this approach warrants further clinical studies.
Talaat, Kawsar R.; Karron, Ruth A.; Callahan, Karen A.; Luke, Catherine J.; DiLorenzo, Susan C.; Chen, Grace L.; Lamirande, Elaine W.; Jin, Hong; Coelingh, Kathy L.; Murphy, Brian R.; Kemble, George; Subbarao, Kanta
Background Live attenuated influenza vaccines (LAIV) are being developed and tested against a variety of influenza viruses with pandemic potential. We describe the results of an open label Phase I trial of a live attenuated H7N3 virus vaccine. Methods and Findings The H7N3 BC 2004/AA ca virus is a live attenuated, cold-adapted, temperature-sensitive influenza virus derived by reverse genetics from the wild-type low pathogenicity avian influenza virus A/chicken/British Columbia/CN-6/2004 (H7N3) and the A/AA/6/60 ca (H2N2) virus that is the Master Donor Virus of the live, intranasal seasonal influenza vaccine. We evaluated the safety, infectivity, and immunogenicity of two doses of 107.5 TCID50 of the vaccine administered by nasal spray 5 weeks apart to normal healthy seronegative adult volunteers in an inpatient isolation unit. The subjects were followed for 2 months after 1 dose of vaccine or for 4 weeks after the second dose. Twenty-one subjects received the first dose of the vaccine, and 17 subjects received two doses. The vaccine was generally well tolerated. No serious adverse events occurred during the trial. The vaccine was highly restricted in replication: 6 (29%) subjects had virus recoverable by culture or by rRT-PCR after the first dose. Replication of vaccine virus was not detected following the second dose. Despite the restricted replication of the vaccine, 90% of the subjects developed an antibody response as measured by any assay: 62% by hemagglutination inhibition assay, 48% by microneutralization assay, 48% by ELISA for H7 HA-specific serum IgG or 71% by ELISA for H7 HA-specific serum IgA, after either one or two doses. Following the first dose, vaccine-specific IgG secreting cells as measured by ELISPOT increased from a mean of 0.1 to 41.6/106 PBMCs; vaccine specific IgA secreting cells increased from 2 to 16.4/106 PBMCs. The antibody secreting cell response after the second dose was less vigorous, which is consistent with the observed low
Herrero, Rolando; Quint, Wim; Hildesheim, Allan; Gonzalez, Paula; Struijk, Linda; Katki, Hormuzd A.; Porras, Carolina; Schiffman, Mark; Rodriguez, Ana Cecilia; Solomon, Diane; Jimenez, Silvia; Schiller, John T.; Lowy, Douglas R.; van Doorn, Leen-Jan; Wacholder, Sholom; Kreimer, Aimée R.
Background Human papillomavirus (HPV) infection, particularly with type 16, causes a growing fraction of oropharyngeal cancers, whose incidence is increasing, mainly in developed countries. In a double-blind controlled trial conducted to investigate vaccine efficacy (VE) of the bivalent HPV 16/18 vaccine against cervical infections and lesions, we estimated VE against prevalent oral HPV infections 4 years after vaccination. Methods and Findings A total of 7,466 women 18–25 years old were randomized (1∶1) to receive the HPV16/18 vaccine or hepatitis A vaccine as control. At the final blinded 4-year study visit, 5,840 participants provided oral specimens (91·9% of eligible women) to evaluate VE against oral infections. Our primary analysis evaluated prevalent oral HPV infection among all vaccinated women with oral and cervical HPV results. Corresponding VE against prevalent cervical HPV16/18 infection was calculated for comparison. Oral prevalence of identifiable mucosal HPV was relatively low (1·7%). Approximately four years after vaccination, there were 15 prevalent HPV16/18 infections in the control group and one in the vaccine group, for an estimated VE of 93·3% (95% CI = 63% to 100%). Corresponding efficacy against prevalent cervical HPV16/18 infection for the same cohort at the same visit was 72·0% (95% CI = 63% to 79%) (p versus oral VE = 0·04). There was no statistically significant protection against other oral HPV infections, though power was limited for these analyses. Conclusions HPV prevalence four years after vaccination with the ASO4-adjuvanted HPV16/18 vaccine was much lower among women in the vaccine arm compared to the control arm, suggesting that the vaccine affords strong protection against oral HPV16/18 infection, with potentially important implications for prevention of increasingly common HPV-associated oropharyngeal cancer. ClinicalTrials.gov, Registry number NCT00128661 PMID:23873171
Khan, Shamshad; Ramesh, B. M.; Doshi, Monika; Becker, Marissa L.
Background Little qualitative research is available on the role of frontline health service providers (FHSPs) in the implementation of clinical trials, particularly in developing countries. This paper presents findings from a qualitative study about the perspectives of FHSPs on future HIV vaccine trials involving female sex workers (FSWs) and men who have sex with men (MSM) in three districts of Karnataka, India. In particular, we explore FHSPs’ knowledge of and views on clinical trials in general, and examine their potential willingness to play a role if such trials were introduced or implemented in the region. Methods A field team of four researchers from Karnataka—two of whom self-identified with FSW or MSM communities (“community researchers”) and two with backgrounds in social work—conducted in-depth interviews with FHSPs. Including community researchers in the study helped to build rapport with FSW and MSM participants and facilitate in-depth discussions. A coding scheme for transcribed and translated data was developed using a framework analysis approach. Data was then analysed thematically using a combination of a priori and emergent codes. Results Over half of FHSPs demonstrated limited knowledge or understanding of clinical trials. Despite reported skepticism around the testing of HIV vaccines in developing countries and concerns around potential side effects, most FHSPs strongly advocated for the implementation of HIV vaccine clinical trials in Karnataka. Further, most FHSPs expressed their willingness to be involved in future HIV vaccine clinical trials in varying capacities. Conclusion Given that FHSPs are often directly involved in the promotion of health and well-being of FSWs and MSM, they are well-positioned to play leadership, ethical, and communicative roles in future HIV vaccine trials. However, our findings reveal a lack of awareness of clinical trials among FHSP participants, suggesting an important area for capacity building and
Nagle, Cate; Lewis, Sharon; Meiser, Bettina; Metcalfe, Sylvia; Carlin, John B; Bell, Robin; Gunn, Jane; Halliday, Jane
Background By providing information on the relative merits and potential harms of the options available and a framework to clarify preferences, decision aids can improve knowledge and realistic expectations and decrease decisional conflict in individuals facing decisions between alternative forms of action. Decision-making about prenatal testing for fetal abnormalities is often confusing and difficult for women and the effectiveness of decision aids in this field has not been established. This study aims to test whether a decision aid for prenatal testing of fetal abnormalities, when compared to a pamphlet, improves women's informed decision-making and decreases decisional conflict. Methods/design A cluster designed randomised controlled trial is being conducted in Victoria, Australia. Fifty General Practitioners (GPs) have been randomised to one of two arms: providing women with either a decision aid or a pamphlet. The two primary outcomes will be measured by comparing the difference in percentages of women identified as making an informed choice and the difference in mean decisional conflict scores between the two groups. Data will be collected from women using questionnaires at 14 weeks and 24 weeks gestation. The sample size of 159 women in both arms of the trial has been calculated to detect a difference of 18% (50 to 68%) in informed choice between the two groups. The required numbers have been adjusted to accommodate the cluster design, miscarriage and participant lost – to – follow up. Baseline characteristics of women will be summarised for both arms of the trial. Similarly, characteristics of GPs will be compared between arms. Differences in the primary outcomes will be analysed using 'intention-to-treat' principles. Appropriate regression techniques will adjust for the effects of clustering and include covariates to adjust for the stratifying variable and major potential confounding factors. Discussion The findings from this trial will make a
Immunogenicity and safety of concomitant administration of a measles, mumps and rubella vaccine (M-M-RvaxPro®) and a varicella vaccine (VARIVAX®) by intramuscular or subcutaneous routes at separate injection sites: a randomised clinical trial
Gillet, Yves; Habermehl, Pirmin; Thomas, Stéphane; Eymin, Cécile; Fiquet, Anne
Background When this trial was initiated, the combined measles, mumps and rubella (MMR) vaccine was licensed for subcutaneous administration in all European countries and for intramuscular administration in some countries, whereas varicella vaccine was licensed only for subcutaneous administration. This study evaluated the intramuscular administration of an MMR vaccine (M-M-RvaxPro®) and a varicella vaccine (VARIVAX®) compared with the subcutaneous route. Methods An open-label randomised trial was performed in France and Germany. Healthy children, aged 12 to18 months, received single injections of M-M-RvaxPro and VARIVAX concomitantly at separate injection sites. Both vaccines were administered either intramuscularly (IM group, n = 374) or subcutaneously (SC group, n = 378). Immunogenicity was assessed before vaccination and 42 days after vaccination. Injection-site erythema, swelling and pain were recorded from days 0 to 4 after vaccination. Body temperature was monitored daily between 0 and 42 days after vaccination. Other adverse events were recorded up to 42 days after vaccination and serious adverse events until the second study visit. Results Antibody response rates at day 42 in the per-protocol set of children initially seronegative to measles, mumps, rubella or varicella were similar between the IM and SC groups for all four antigens. Response rates were 94 to 96% for measles, 98% for both mumps and rubella and 86 to 88% for varicella. For children initially seronegative to varicella, 99% achieved the seroconversion threshold (antibody concentrations of ≥ 1.25 gpELISA units/ml). Erythema and swelling were the most frequently reported injection-site reactions for both vaccines. Most injection-site reactions were of mild intensity or small size (≤ 2.5 cm). There was a trend for lower rates of injection-site erythema and swelling in the IM group. The incidence and nature of systemic adverse events were comparable for the two routes of administration
Soola, E O
Attention is focused on the segmentation of the audience (urban, rural, urban slum) and messages, and on how appropriate communication and educational strategies can be adopted to create awareness of AIDS among the African population. It is important to determine the scope, nature, and content of the message in addition to the delivery of these messages through proper channels. Channels of communication vary in reach and influence, and different segments of the population vary in the capacity to absorb information. Rural people are considered susceptible because of their penchant for continually using injections for treatment of any ailment; the source of concern is unsterilized needles and syringes. The semantics of AIDs is discussed to emphasize the problem of how to identify AIDs among the multiplicity of languages in individual countries. For instance, in Nigeria there may be 150-400 languages, and these languages lack systematically developed metalanguage and specialized vocabularies. The view that local language use must be one way, linear is accepted, and the difficulties surmounted. Local languages may be used to transmit information of a nontechnical nature. The literate minority should have access to detailed information on causes, modes of transmission, symptoms, treatment or management, but not everyone needs this extent of detail. The rural and urban residents should know about the incurability of the disease, the mode of transmission, its symptoms, and what should be done if someone is suspected of having an HIV infection. Already the Hausa of Nigeria have a term for AIDs, Karya-Garkuwa, which suggests a disease that breaks down the mechanism of the biological functioning of the body. Communicators must be knowledgeable and able to effectively transmit facts not myths. Of the 3 modes of transmission (sex, blood, mother to child), sexual transmission is the most important. Blood routes are through transfusions, contaminated blood products for
Pertussis incidence has increased in recent years, especially among infants aged <2months. A number of Spanish regions have started a vaccination program with Tdap vaccine to all pregnant women in the third trimester of pregnancy. An observational study has shown that this strategy reduces the number of cases of pertussis by 90% in infants aged <2months. Mathematical models showed that a cocooning strategy (i.e. vaccination of the mother at immediate postpartum, and other adults and adolescents who have close contact with the newborn and caregivers) will reduce the incidence of pertussis by 70% in infants aged <2months. It is intended to conduct a clinical trial in which 340 pregnant women will receive Tdap vaccine, whereas another 340 pregnant woman will be vaccinated soon after delivery. Vaccination with Tdap will be offered to all partners and caregivers of the newborn. After assessing both the ethical and scientific reasons supporting the trial, it is concluded that it is ethically and legally acceptable to invite pregnant women living in communities where Tdap vaccination has been implemented to participate in the trial.
Hwang, Thomas J; Kesselheim, Aaron S
Many serious diseases lack safe and effective vaccines. Using a large commercial database, we examined trends in global vaccine research and development and found that the proportion of new vaccine candidates entering all stages of clinical development increased by 3-5 percentage points over the past two decades. Small and medium-size companies accounted for nearly twice as many new Phase I vaccine trials compared to large companies, but late-stage (Phase III) vaccine trials were dominated by large companies. There were no significant differences between vaccines and drugs in the probability of success in clinical trials or in profitability. Small and medium-size companies, including spin-outs from academic research centers, play an important role in innovative research and discovery. Our findings suggest that policy making targeted at smaller companies, such as prizes or opportunities for public-private partnerships, could support the development of new vaccines, particularly those targeting unmet medical needs and emerging public health threats.
Cox, Josephine H; Ferrari, Guido; Kalams, Spyros A; Lopaczynski, Wlodek; Oden, Neal; D'souza, M Patricia
We used an external quality assurance (EQA) panel to assess laboratory competency and comparability when performing ELISPOT assays in support of human immunodeficiency virus type 1 (HIV-1) vaccine trials. Cell recovery, viability, and frequency of interferon-gamma (IFN-gamma)-secreting cells after antigen stimulation were obtained from 11 laboratories on a coded panel of 11 peripheral blood mononuclear cell samples. The median recovery and viability before plating for all samples were 35% and 86%, respectively, with notable interlaboratory and intrasample variability. Empirical as well as statistical analysis methods were used to define positive ELISPOT responses. Remarkable concordance between laboratories was obtained in defining a qualitative assessment of responder/nonresponder status to antigens, but the frequency of responding cells varied among the laboratories. This study highlights the need for better standardization of protocols and reagents to obtain reliable and reproducible data that may support immunogenicity studies, vaccine regulatory submissions, and licensure.
Verotta, Davide; Schaedeli, Franziska
illustration we demonstrate an application of the models using real AIDS clinical trial data involving patients treated with a combination of anti-retroviral agents using a model which incorporates compliance data.
Ackerman, Margaret; Saunders, Kevin O.; Pollara, Justin; Vandergrift, Nathan; Parks, Rob; Michael, Nelson L.; O’Connell, Robert J.; Vasan, Sandhya; Rerks-Ngarm, Supachai; Kaewkungwal, Jaranit; Pitisuttithum, Punnee; Nitayaphan, Sorachai; Sinangil, Faruk; Phogat, Sanjay; Alam, S. Munir; Liao, Hua-Xin; Ferrari, Guido; Seaman, Michael S.; Montefiori, David C.; Harrison, Stephen C.; Haynes, Barton F.
The canary pox vector and gp120 vaccine (ALVAC-HIV and AIDSVAX B/E gp120) in the RV144 HIV-1 vaccine trial conferred an estimated 31% vaccine efficacy. Although the vaccine Env AE.A244 gp120 is antigenic for the unmutated common ancestor of V1V2 broadly neutralizing antibody (bnAbs), no plasma bnAb activity was induced. The RV305 (NCT01435135) HIV-1 clinical trial was a placebo-controlled randomized double-blinded study that assessed the safety and efficacy of vaccine boosting on B cell repertoires. HIV-1-uninfected RV144 vaccine recipients were reimmunized 6–8 years later with AIDSVAX B/E gp120 alone, ALVAC-HIV alone, or a combination of ALVAC-HIV and AIDSVAX B/E gp120 in the RV305 trial. Env-specific post-RV144 and RV305 boost memory B cell VH mutation frequencies increased from 2.9% post-RV144 to 6.7% post-RV305. The vaccine was well tolerated with no adverse events reports. While post-boost plasma did not have bnAb activity, the vaccine boosts expanded a pool of envelope CD4 binding site (bs)-reactive memory B cells with long third heavy chain complementarity determining regions (HCDR3) whose germline precursors and affinity matured B cell clonal lineage members neutralized the HIV-1 CRF01 AE tier 2 (difficult to neutralize) primary isolate, CNE8. Electron microscopy of two of these antibodies bound with near-native gp140 trimers showed that they recognized an open conformation of the Env trimer. Although late boosting of RV144 vaccinees expanded a novel pool of neutralizing B cell clonal lineages, we hypothesize that boosts with stably closed trimers would be necessary to elicit antibodies with greater breadth of tier 2 HIV-1 strains. Trial Registration: ClinicalTrials.gov NCT01435135 PMID:28235027
Flynn, Patricia M.; Cunningham, Coleen K.; Rudy, Bret; Wilson, Craig M.; Kapogiannis, Bill; Worrell, Carol; Bethel, James; Monte, Dina; Bojan, Kelly
Background HIV-infected youth are at risk of hepatitis B (HBV) infection and should be vaccinated. Previous reports suggest reduced response to standard HBV vaccine regimens. Methods HIV-infected youth, age 12 to <25 years, were randomly assigned to one of three treatment arms: Arm 1: Engerix B®, 20 mcg HBsAg; Arm 2: Engerix B®, 40 mcg; and Arm 3: Twinrix®, 20mcg HBsAg combined with 720 ELU hepatitis A antigen. Vaccines were administered at weeks 0, 4 and 24. Results Characteristics of evaluable patients (n=336) at entry were similar in the study arms. At enrollment, median CD4+ T-cell count was 460 cells/mm3 (IQR: 305 to 668); 13% were < 200 cells/mm3. Among Engerix B®, 20 mcg recipients, 60.4% responded to vaccine (HBsAb ≥ 10 IU/mL at week 28). Improved vaccine response was seen in recipients of Engerix B®, 40 mcg, (73.2%, vs. Arm 1, p=0.04) and Twinrix® (75.4%, vs. Arm 1, p=0.02). In multivariate analysis, only baseline CD4+ T-cell count and study arm were independent predictors of vaccine response. Conclusions In HIV-infected youth, a three dose vaccination regimen with Engerix B®, 40 mcg, or Twinrix® and higher baseline CD4+ T-cell counts were independently associated with improved vaccine response. PMID:21350366
Ditkowsky, Jared B; Schwartzman, Kevin
Novel tuberculosis vaccines are in varying stages of pre-clinical and clinical development. This study seeks to estimate the potential cost-effectiveness of a BCG booster vaccine, while accounting for costs of large-scale clinical trials, using the MVA85A vaccine as a case study for estimating potential costs. We conducted a decision analysis from the societal perspective, using a 10-year time frame and a 3% discount rate. We predicted active tuberculosis cases and tuberculosis-related costs for a hypothetical cohort of 960,763 South African newborns (total born in 2009). We compared neonatal vaccination with bacille Calmette-Guérin alone to vaccination with bacille Calmette-Guérin plus a booster vaccine at 4 months. We considered booster efficacy estimates ranging from 40% to 70%, relative to bacille Calmette-Guérin alone. We accounted for the costs of Phase III clinical trials. The booster vaccine was assumed to prevent progression to active tuberculosis after childhood infection, with protection decreasing linearly over 10 years. Trial costs were prorated to South Africa's global share of bacille Calmette-Guérin vaccination. Vaccination with bacille Calmette-Guérin alone resulted in estimated tuberculosis-related costs of $89.91 million 2012 USD, and 13,610 tuberculosis cases in the birth cohort, over the 10 years. Addition of the booster resulted in estimated cost savings of $7.69-$16.68 million USD, and 2,800-4,160 cases averted, for assumed efficacy values ranging from 40%-70%. A booster tuberculosis vaccine in infancy may result in net societal cost savings as well as fewer active tuberculosis cases, even if efficacy is relatively modest and large scale Phase III studies are required.
Doumbo, O K; Djimdé, A A; Théra, M A
In the 20th century malaria remains a major problem of public health in sub-Saharan Africa. This haemosporidium discovered in Africa by Laveran in 1880, kills one child every 30 seconds which amounts to three "tsunami" flowing each year into the African continent. The current international solidarity raises new hopes as regards the possibility to suppress the morbidity effects on the population's health condition. In order to be efficient, today's strategies (impregnated mosquito nets, intermittent preventive treatments, artemisinin based combination therapy) should reach at least 80% of the targeted population (pregnant women and children). By 2025, the uncontrolled urbanization of the African population and the social disorders will make a new population a target for malaria. The new data of functional genomics and proteonics open new avenues of research for new mechanisms, new therapeutics and vaccine targets and new tools of diagnosis and prognosis. The current candidate vaccines of the first generation have allowed the development of African competences in clinical trials of international standard. Although they represent scientific advances they will not resolve the problem of public health. Research on candidate vaccines of 2nd and 3rd generation remains a challenge for the international scientific community. Africa should play a determining role in this process. Scientific information on the field remains essential for these generations of new anti-malarial vaccines. The ethical aspects regarding those clinical trials and actions of public health and research remain an universal necessity Deontology and ethics are two complementary approaches for the good practice of medicine and research of a good practitioner. For the protection and advantages of the patient and/or volunteer of the research are the cornerstones of the ethical approach. The scientific quality of a research protocol submitted to an independent research ethics committee and the volunteer 's
Yee, Joann L; McChesney, Michael B; Christe, Kari L
Measles is a highly contagious viral disease in NHP. The infection can range from asymptomatic to rapidly fatal, resulting in significant morbidity and mortality in captive populations. In addition to appropriate quarantine practices, restricted access, the immunization of all personnel in contact with NHP, and the wearing of protective clothing including face masks, measles immunization further reduces the infection risk. Commercially available measles vaccines are effective for use in NHP, but interruptions in their availability have prevented the implementation of ongoing, consistent vaccination programs. This need for a readily available vaccine led us to perform a broad, multicenter safety and immunogenicity study of another candidate vaccine, MVac (Serum Institute of India), a monovalent measles vaccine derived from live Edmonston-Zagreb strain virus that had been attenuated after 22 passages on human diploid cells.
Yee, JoAnn L; McChesney, Michael B; Christe, Kari L
Measles is a highly contagious viral disease in NHP. The infection can range from asymptomatic to rapidly fatal, resulting in significant morbidity and mortality in captive populations. In addition to appropriate quarantine practices, restricted access, the immunization of all personnel in contact with NHP, and the wearing of protective clothing including face masks, measles immunization further reduces the infection risk. Commercially available measles vaccines are effective for use in NHP, but interruptions in their availability have prevented the implementation of ongoing, consistent vaccination programs. This need for a readily available vaccine led us to perform a broad, multicenter safety and immunogenicity study of another candidate vaccine, MVac (Serum Institute of India), a monovalent measles vaccine derived from live Edmonston–Zagreb strain virus that had been attenuated after 22 passages on human diploid cells. PMID:26473350
Amador, R; Moreno, A; Valero, V; Murillo, L; Mora, A L; Rojas, M; Rocha, C; Salcedo, M; Guzman, F; Espejo, F
This paper reports the results of the first field study performed to assess the safety, immunogenicity and protectivity of the synthetic malaria vaccine SPf66 directed against the asexual blood stages of Plasmodium falciparum. Clinical and laboratory tests were performed on all volunteers prior to and after each immunization, demonstrating that no detectable alteration was induced by the immunization process. The vaccines were grouped as high, intermediate or low responders according to their antibody titres directed against the SPf66 molecule. Two of the 185 (1.08%) SPf66-vaccinated and nine of the 214 (4.20%) placebo-vaccinated volunteers developed P. falciparum malaria. The efficacy of the vaccine was calculated as 82.3% against P. falciparum and 60.6% against Plasmodium vivax.
Flanagan, K L; van Crevel, R; Curtis, N; Shann, F; Levy, O
A growing body of evidence from epidemiologic, clinical, and immunologic studies indicates that vaccines can influence morbidity and mortality independent of vaccine-specific B-cell or T-cell immunity. For example, the live attenuated measles vaccine and BCG vaccine may reduce mortality from infections other than measles or tuberculosis, respectively. Immunologists call these heterologous effects and epidemiologists have called them nonspecific effects, indicating that they manifest against a broad range of pathogens/disease. These effects differ by sex, can be beneficial or detrimental, and appear to be mediated by mechanisms including innate immune memory (also known as "trained immunity") and cross-reacting lymphocytes. Herein we review recent studies in this emerging field based on a meeting of experts, the recent Optimmunize meeting, held in Copenhagen, Denmark, in August 2012. Further characterization of these effects is likely to expand the way vaccines are evaluated and alter the manner and sequence in which they are given.
da Costa, Vivaldo G; Marques-Silva, Ariany C; Floriano, Vitor G; Moreli, Marcos L
The World Health Organization has stipulated a target: reduce the mortality rate caused by dengue disease by 50% until 2020. Most likely, this goal can be achieved by means of a dengue vaccine. Accordingly, the recombinant and tetravalent dengue vaccine (CYD-TDV), developed by the Sanofi Pasteur Group, is in an advanced stage of human testing. Although there are multiple randomized, placebo-controlled trials evaluating the CYD-TDV, individual results may have little power to identify differences between the populations studied. Thus, we conducted a meta-analysis to determine a more precise estimate of the overall parameters of safety, immunogenicity and efficacy of CYD-TDV. A data search was conducted in the PubMed, Medline, Cochrane Central Register of Controlled Trials and SciELO databases with defined selection criteria. We included for meta-analysis seven randomized and placebo-controlled studies that included 6678 patients randomized to receive the CYD-TDV (4586) or placebo (2092). Regarding vaccine safety, it was found that there was no significant difference between treated and placebo groups, as only approximately 5.5% of patients were withdrawn from the study. Regarding immunogenicity, the levels of neutralizing antibodies were measured by weighted mean differences (WMD), which were always higher in the vaccinated group (WMD/DENV1=59.7, 95% confidence interval [CI] 57-61; WMD/DENV2=99, 95% CI 95-102; WMD/DENV3=138, 95% CI 133-142; WMD/DENV4=123, 95% CI 119-126). The clinical efficacy of the vaccine was 59% (95% CI 15-80; RR=0.41, 95% CI 0.2-0.85, I(2)=30.9%). In conclusion, safety and a balanced immune response to the CYD-TDV were found. However, to fully establish the clinical effectiveness and robustness of immunogenicity, it is necessary to perform further studies to assess the long-term effects of the vaccine.
Martins, Cesario L; Benn, Christine S; Andersen, Andreas; Balé, Carlito; Schaltz-Buchholzer, Frederik; Do, Vu An; Rodrigues, Amabelia; Aaby, Peter; Ravn, Henrik; Whittle, Hilton; Garly, May-Lill
Observational studies and trials from low-income countries indicate that measles vaccine has beneficial nonspecific effects, protecting against non-measles-related mortality. It is not known whether measles vaccine protects against hospital admissions. Between 2003 and 2007, 6417 children who had received the third dose of diphtheria, tetanus, and pertussis vaccine were randomly assigned to receive measles vaccine at 4.5 months or no measles vaccine; all children were offered measles vaccine at 9 months of age. Using hospital admission data from the national pediatric ward in Bissau, Guinea-Bissau, we compared admission rates between enrollment and the 9-month vaccination in Cox models, providing admission hazard rate ratios (HRRs) for measles vaccine versus no measles vaccine. All analyses were conducted stratified by sex and reception of neonatal vitamin A supplementation (NVAS). Before enrollment the 2 groups had similar admission rates. Following enrollment, the measles vaccine group had an admission HRR of 0.70 (95% confidence interval [CI], .52-.95), with a ratio of 0.53 (95% CI, .32-.86) for girls and 0.86 (95% CI, .58-1.26) for boys. For children who had not received NVAS, the admission HRR was 0.53 (95% CI, .34-.84), with an effect of 0.30 (95% CI, .13-.70) for girls and 0.73 (95% CI, .42-1.28) for boys (P = .08, interaction test). The reduction in admissions was separately significant for measles infection (admission HRR, 0 [95% CI, 0-.24]) and respiratory infections (admission HRR, 0.37 [95% CI, .16-.89]). Early measles vaccine may have major benefits for infant morbidity patterns and healthcare costs. Clinical trials registration NCT00168558.
Doedée, Anne M. C. M.; Boland, Greet J.; Pennings, Jeroen L. A.; de Klerk, Arja; Berbers, Guy A. M.; van der Klis, Fiona R. M.; de Melker, Hester E.; van Loveren, Henk; Janssen, Riny
Worldwide, paracetamol is administered as a remedy for complaints that occur after vaccination. Recently published results indicate that paracetamol inhibits the vaccination response in infants when given prior to vaccination. The goal of this study was to establish whether paracetamol exerts similar effects in young adults. In addition, the effect of timing of paracetamol intake was investigated. In two randomized, controlled, open-label studies 496 healthy young adults were randomly assigned to three groups. The study groups received paracetamol for 24 hours starting at the time of (prophylactic use) - or 6 hours after (therapeutic use) the primary (0 month) and first booster (1 month) hepatitis B vaccination. The control group received no paracetamol. None of the participants used paracetamol around the second booster (6 months) vaccination. Anti-HBs levels were measured prior to and one month after the second booster vaccination on ADVIA Centaur XP. One month after the second booster vaccination, the anti-HBs level in the prophylactic paracetamol group was significantly lower (p = 0.048) than the level in the control group (4257 mIU/mL vs. 5768 mIU/mL). The anti-HBs level in the therapeutic paracetamol group (4958 mIU/mL) was not different (p = 0.34) from the level in the control group. Only prophylactic paracetamol treatment, and not therapeutic treatment, during vaccination has a negative influence on the antibody concentration after hepatitis B vaccination in adults. These findings prompt to consider therapeutic instead of prophylactic treatment to ensure maximal vaccination efficacy and retain the possibility to treat pain and fever after vaccination. Trial Registration Controlled-Trials.com ISRCTN03576945 PMID:24897504
Madan, Anuradha; Segall, Nathan; Ferguson, Murdo; Frenette, Louise; Kroll, Robin; Friel, Damien; Soni, Jyoti; Li, Ping; Innis, Bruce L.; Schuind, Anne
Background. Almost 700 cases of human infection with avian influenza A/H7N9 have been reported since 2013. Pandemic preparedness strategies include H7N9 vaccine development. Methods. We evaluated an inactivated H7N9 vaccine in an observer-blind study in healthy adults aged 18–64 years. Participants (420) were randomized to receive 1 of 4 AS03-adjuvanted vaccines (low or medium dose of hemagglutinin with AS03A or AS03B), one nonadjuvanted vaccine, or placebo. The coprimary immunogenicity objective determined whether adjuvanted vaccines elicited an immune response against the vaccine-homologous virus, 21 days after the second vaccine dose per US and European licensure criteria in the per-protocol cohort (n = 389). Results. All adjuvanted vaccines met regulatory acceptance criteria. In groups receiving adjuvanted formulations, seroconversion rates were ≥85.7%, seroprotection rates ≥91.1%, and geometric mean titers ≥92.9% versus 23.2%, 28.6%, and 17.2 for the nonadjuvanted vaccine. The AS03 adjuvant enhanced immune response at antigen-sparing doses. Injection site pain occurred more frequently with adjuvanted vaccines (in ≤98.3% of vaccinees) than with the nonadjuvanted vaccine (40.7%) or placebo (20.0%). None of the 20 serious adverse events reported were related to vaccination. Conclusions. Two doses of AS03-adjuvanted H7N9 vaccine were well tolerated and induced a robust antibody response at antigen-sparing doses in healthy adults. Clinical Trials Registration. NCT01999842. PMID:27609809
Jimenez, Manuel E; DuRivage, Nathalie E; Bezpalko, Orysia; Suh, Andrew; Wade, Roy; Blum, Nathan J; Fiks, Alexander G
Many young children identified with developmental concerns in pediatric settings do not receive early intervention (EI). We assessed the impact of a video decision aid and text message reminder on knowledge and attitudes regarding developmental delay and EI as well as referral completion. We conducted a pilot randomized controlled trial in an urban setting and enrolled 64 parent-child dyads referred to EI. Compared with controls, participants who received the intervention demonstrated increased knowledge regarding developmental delay and EI as well as more favorable attitudes in certain topics. Although we did not find a significant difference between arms in EI intake and evaluation, we found a pattern suggestive of increased intake and evaluation among participants with low health literacy in the intervention arm. Additional study is needed to identify strategies that improve the EI referral process for families and to understand the potential targeted role for decision aids and text messages.
Paolini, A; Ridolfi, V; Zezza, D; Cocchietto, M; Musa, M; Pavone, A; Conte, A; Giorgetti, G
Photobacterium damsela subsp. piscicida (Phdp) is the aetiological agent of fish pasteurellosis, causing heavy losses in intensive mariculture plants. The present work compares the protective efficacy of five different vaccine formulation: oral, intraperitoneal, immersion, bivalent immersion (Vibrio anguillarum) and immersion associated with immunostimulants. Each of these vaccine formulations containing whole cells of Phdp formalin inactivated (FKC), was administered to 100 sea bass weighing approximately 2 g; 100 non-vaccinated sea bass were used as controls. Protection against pasteurellosis was tested for 40 days after vaccination by intraperitoneal challenge: each fish was inoculated with Phdp cells at a concentration of 2.75 x 10(4) cfu/ml. Mortality was recorded over the following 14 days, vaccine protection was evaluated using a relative percentage survival (RPS) index. The intraperitoneal formulation gave excellent protection (RPS 82.4%). The most effective immersion form was that followed by simple immersion (RPS 23.1%) followed by the group vaccinated with bivalent vaccine (RPS 18.7%). Protection conferred orally (RPS 28.6%) is of interest for practical purposes.
Lindesmith, Lisa C.; Ferris, Martin T.; Mullan, Clancy W.; Ferreira, Jennifer; Debbink, Kari; Swanstrom, Jesica; Richardson, Charles; Goodwin, Robert R.; Baehner, Frank; Mendelman, Paul M.; Bargatze, Robert F.; Baric, Ralph S.
support the potential feasibility of an efficacious multivalent NoV VLP vaccine for future use in human populations. Trial Registration ClinicalTrials.gov NCT01168401 PMID:25803642
Townsend, H G; Penner, S J; Watts, T C; Cook, A; Bogdan, J; Haines, D M; Griffin, S; Chambers, T; Holland, R E; Whitaker-Dowling, P; Youngner, J S; Sebring, R W
A randomised, controlled, double-blind, influenza virus, aerosol challenge of horses was undertaken to determine the efficacy of a cold-adapted, temperature sensitive, modified-live virus, intranasal, equine influenza vaccine. Ninety 11-month-old influenza-naïve foals were assigned randomly to 3 groups (20 vaccinates and 10 controls per group) and challenged 5 weeks, 6 and 12 months after a single vaccination. Challenges were performed on Day 0 in a plastic-lined chamber. Between Days 1 and 10, animals were examined daily for evidence of clinical signs of influenza. Nasal swabs for virus isolation were obtained on Day 1 and Days 1 to 8 and blood samples for serology were collected on Days 1, 7 and 14. There was no adverse response to vaccination in any animal. Following challenge at 5 weeks and 6 months, vaccinates had significantly lower clinical scores (P = 0.0001 and 0.005, respectively), experienced smaller increases in rectal temperature (P = 0.0008 and 0.0007, respectively) and shed less virus (P<0.0001 and P = 0.03, respectively) over fewer days (P<0.0001 and P = 0.002, respectively) than did the controls. After the 12 month challenge, rectal temperatures (P = 0.006) as well as the duration (P = 0.03) and concentration of virus shed (P = 0.04) were significantly reduced among vaccinated animals. The results of this study showed that 6 months after a single dose of vaccine the duration and severity of clinical signs were markedly reduced amongst vaccinated animals exposed to a severe live-virus challenge. Appropriate use of this vaccine should lead to a marked reduction in the frequency, severity and duration of outbreaks of equine influenza in North America.
Simpson, Michael A.
Describes "Instant Experience," a simulation and game method in which students are given information about a promising new drug and asked to design a protocol for a clinical trial of the drug. Evaluation of a trial workshop showed positive response to the method. Educational goals to be achieved through its use are noted. (JT)
White, Michael T; Verity, Robert; Churcher, Thomas S; Ghani, Azra C
A licensed malaria vaccine would provide a valuable new tool for malaria control and elimination efforts. Several candidate vaccines targeting different stages of the malaria parasite's lifecycle are currently under development, with one candidate, RTS,S/AS01 for the prevention of Plasmodium falciparum infection, having recently completed Phase III trials. Predicting the public health impact of a candidate malaria vaccine requires using clinical trial data to estimate the vaccine's efficacy profile--the initial efficacy following vaccination and the pattern of waning of efficacy over time. With an estimated vaccine efficacy profile, the effects of vaccination on malaria transmission can be simulated with the aid of mathematical models. Here, we provide an overview of methods for estimating the vaccine efficacy profiles of pre-erythrocytic vaccines and transmission-blocking vaccines from clinical trial data. In the case of RTS,S/AS01, model estimates from Phase II clinical trial data indicate a bi-phasic exponential profile of efficacy against infection, with efficacy waning rapidly in the first 6 months after vaccination followed by a slower rate of waning over the next 4 years. Transmission-blocking vaccines have yet to be tested in large-scale Phase II or Phase III clinical trials so we review ongoing work investigating how a clinical trial might be designed to ensure that vaccine efficacy can be estimated with sufficient statistical power. Finally, we demonstrate how parameters estimated from clinical trials can be used to predict the impact of vaccination campaigns on malaria using a mathematical model of malaria transmission.
Burke, M Susan
This review of the data from the Shingles Prevention Study (SPS) highlights the efficacy and safety of a high-titer live attenuated herpes zoster virus vaccine in preventing herpes zoster and postherpetic neuralgia (PHN) in adults aged 60 years or older. In the SPS, the vaccine reduced the burden of illness due to herpes zoster disease by 61.1% and the incidence of its most common and debilitating sequela, PHN, by 66.5%. In addition, vaccination was associated with a 51.3% reduction in the overall incidence of herpes zoster. Also, subjects in whom herpes zoster did develop had decreased pain and discomfort. The vaccine was safe in the SPS population, with little differentiation from the safety profile of placebo other than an increased risk for reactions at the injection site. Rates of serious adverse events, systemic adverse events, hospitalization, and death were low and similar to those observed in the group that received placebo.
Desai, Sachin N; Akalu, Zenebe; Teshome, Samuel; Teferi, Mekonnen; Yamuah, Lawrence; Kim, Deok Ryun; Yang, Jae Seung; Hussein, Jemal; Park, Ju Yeong; Jang, Mi Seon; Mesganaw, Chalachew; Taye, Hawult; Beyene, Demissew; Bedru, Ahmed; Singh, Ajit Pal; Wierzba, Thomas F; Aseffa, Abraham
Killed whole-cell oral cholera vaccine (OCV) has been a key component of a comprehensive package including water and sanitation measures for recent cholera epidemics. The vaccine, given in a two-dose regimen, has been evaluated in a large number of human volunteers in India, Vietnam, and Bangladesh, where it has demonstrated safety, immunogenicity, and clinical efficacy. We conducted a double-blind randomized placebo-controlled trial in Ethiopia, where we evaluated the safety and immunogenicity of the vaccine in 216 healthy adults and children. OCV was found to be safe and elicited a robust immunological response against Vibrio cholerae O1, with 81% adults and 77% children demonstrating seroconversion 14 days after the second dose of vaccine. This is the first study to evaluate safety and immunogenicity of the vaccine in a population outside Asia using a placebo-controlled, double-blind, randomized study design.
Beignon, Anne-Sophie; Mollier, Karine; Liard, Christelle; Coutant, Frédéric; Munier, Sandie; Rivière, Julie; Souque, Philippe; Charneau, Pierre
AIDS vaccination has a pressing need for more potent vaccination vectors capable of eliciting strong, diversified, and long-lasting cellular immune responses against human immunodeficiency virus (HIV). Lentiviral vectors have demonstrated efficiency not only as gene delivery vehicles for gene therapy applications but also as vaccination tools. This is likely due to their ability to transduce nondividing cells, including dendritic cells, enabling sustained endogenous antigen presentation and thus the induction of high proportions of specific cytotoxic T cells and long-lasting memory T cells. We show in a first proof-of-concept pilot study that a prime/boost vaccination strategy using lentiviral vectors pseudotyped with a glycoprotein G from two non-cross-reactive vesicular stomatitis virus serotypes elicited robust and broad cellular immune responses against the vector-encoded antigen, simian immunodeficiency virus (SIV) GAG, in cynomolgus macaques. Vaccination conferred strong protection against a massive intrarectal challenge with SIVmac251, as evidenced both by the reduction of viremia at the peak of acute infection (a mean of over 2 log(10) fold reduction) and by the full preservation of the CD28(+) CD95(+) memory CD4(+) T cells during the acute phase, a strong correlate of protection against pathogenesis. Although vaccinees continued to display lower viremia than control macaques during the early chronic phase, these differences were not statistically significant by day 50 postchallenge. A not-optimized SIV GAG antigen was chosen to show the strong potential of the lentiviral vector system for vaccination. Given that a stronger protection can be anticipated from a modern HIV-1 antigen design, gene transfer vectors derived from HIV-1 appear as promising candidates for vaccination against HIV-1 infection.
Barreto, Mauricio L; Pilger, Daniel; Pereira, Susan M; Genser, Bernd; Cruz, Alvaro A; Cunha, Sergio S; Sant'Anna, Clemax; Hijjar, Miguel A; Ichihara, Maria Y; Rodrigues, Laura C
BCG protection varies and in some places (nearest the equator) is low or absent. Understanding this variation can inform the efforts to develop new vaccines against tuberculosis. Two main hypotheses are used to explain this variation: under masking, new vaccines are unlikely to increase protection; under blocking new vaccines have a greater potential to be effective when BCG is not. We conducted a cluster randomized trial to explored the masking and blocking hypotheses by studying BCG vaccine efficacy of neonatal vaccination and when administered for the first or a second (revaccination) time at school age in two sites (Manaus close and Salvador further south from the equator). Seven hundred and sixty three state schools were matched on socio economic characteristics of the neighborhood and 239,934 children were randomized to vaccine (BCG vaccination at school age) or control group. Protection by first BCG vaccination at school age was high in Salvador (34%, 95% CI 7-53%, p=0.017) but low in Manaus (8%, 95% CI t0 39-40%, p=0.686). For revaccination at school age, protection was modest in Salvador (19%, 95% CI 3-33%, p=0.022) and absent in Manaus (1%, 95% CI to 27-23%, p=0.932). Vaccine efficacy for neonatal vaccination was similar in Salvador (40%, 95% CI 22-54%, p<0.001) and Manaus (36%, 95% CI 11-53%, p=0.008). Variation in BCG efficacy was marked when vaccine was given at school age but absent at birth, which points towards blocking as the dominant mechanism. New tuberculosis vaccines that overcome or by pass this blocking effect could confer protection in situations where BCG is not protective.
Han, Seung Beom; Rhim, Jung-Woo; Shin, Hye Jo; Lee, Soo Young; Kim, Hyun-Hee; Kim, Jong-Hyun; Lee, Kyung-Yil; Ma, Sang Hyuk; Park, Joon Soo; Kim, Hwang Min; Kim, Chun Soo; Kim, Dong Ho; Choi, Young Youn; Cha, Sung-Ho; Hong, Young Jin; Kang, Jin Han
A multicenter, double-blind, randomized, active-control phase III clinical trial was performed to assess the immunogenicity and safety of a trivalent, inactivated split influenza vaccine. Korean children between the ages of 6 months and 18 y were enrolled and randomized into a study (study vaccine) or a control vaccine group (commercially available trivalent, inactivated split influenza vaccine) in a 5:1 ratio. Antibody responses were determined using hemagglutination inhibition assay, and post-vaccination immunogenicity was assessed based on seroconversion and seroprotection rates. For safety assessment, solicited local and systemic adverse events up to 28 d after vaccination and unsolicited adverse events up to 6 months after vaccination were evaluated. Immunogenicity was assessed in 337 and 68 children of the study and control groups. In the study vaccine group, seroconversion rates against influenza A/H1N1, A/H3N2, and B strains were 62.0% (95% CI: 56.8-67.2), 53.4% (95% CI: 48.1-58.7), and 54.9% (95% CI: 48.1-60.2), respectively. The corresponding seroprotection rates were 95.0% (95% CI: 92.6-97.3), 93.8% (95% CI: 91.2-96.4), and 95.3% (95% CI: 93.0-97.5). The lower 95% CI limits of the seroconversion and seroprotection rates were over 40% and 70%, respectively, against all strains. Seroconversion and seroprotection rates were not significantly different between the study and control vaccine groups. Furthermore, the frequencies of adverse events were not significantly different between the 2 vaccine groups, and no serious vaccination-related adverse events were noted. In conclusion, the study vaccine exhibited substantial immunogenicity and safety in Korean children and is expected to be clinically effective.
Gailhardou, Sophia; Skipetrova, Anna; Dayan, Gustavo H.; Jezorwski, John; Saville, Melanie; Van der Vliet, Diane; Wartel, T. Anh
A recombinant live attenuated tetravalent dengue vaccine (CYD-TDV) has been shown to be efficacious in preventing virologically-confirmed dengue disease, severe dengue disease and dengue hospitalization in children aged 2–16 years in Asia and Latin America. We analyzed pooled safety data from 18 phase I, II and III clinical trials in which the dengue vaccine was administered to participants aged 2–60 years, including long-term safety follow-up in three efficacy trials. The participants were analyzed according to their age at enrollment. The percentage of participants aged 2–60 years reporting ≥1 solicited injection-site or systemic reactions was slightly higher in the CYD-TDV group than in the placebo group. The most common solicited injection-site reactions were pain. Headache and malaise were the most common solicited systemic reactions. In both groups 0.3% of participants discontinued for safety reasons. The most common unsolicited adverse events were injection-site reactions, gastrointestinal disorders, and infections. Reactogenicity did not increase with successive doses of CYD-TDV. The frequency and nature of SAEs occurring within 28 days of any dose were similar in the CYD-TDV and placebo groups and were common medical conditions that could be expected as a function of age. Baseline dengue virus serostatus did not appear to influence the safety profile. No vaccine-related anaphylactic reactions, neurotropic events or viscerotropic events were reported. In year 3 after dose 1, an imbalance for dengue hospitalization, including for severe dengue, observed in participants aged <9 years in the CYD-TDV group compared with the placebo group was not observed for participants aged ≥9 years. In Year 4, this imbalance in participants aged <9 years was less marked, giving an overall lower risk of dengue hospitalization or severe dengue from dose 1 to Year 4 in the CYD-TDV group. These results have contributed to the definition of the target population for
Troy, Jesse D.; Hill, Heather R.; Ewell, Marian G.; Frey, Sharon E.
Introduction Previous research shows immune response to vaccination differs by sex but this has not been explored for IMVAMUNE®, a replication-deficient smallpox vaccine developed in response to the potential for bioterrorism using smallpox. Methods We conducted a participant-level meta-analysis (N=275, 136 men, 139 women) of 3 randomized trials of IMVAMUNE conducted at 13 centers in the US through a federally-funded extramural research program. Studies were eligible for inclusion if they tested the standard dose (1×108 TCID50/mL on Days 0 and 28) of liquid formulation IMVAMUNE, were completed at the time of our search, and enrolled healthy vaccinia-naïve participants. Models of the peak log2 ELISA and PRNT titers post-second vaccination were constructed for each study with sex as a covariate. Results from these models were combined into random effects meta-analyses of the sex difference in response to IMVAMUNE. We then compared this approach with fixed effects models using the combined participant level data. Results In each study the mean peak log2 ELISA titer was higher in men than women but no single study demonstrated a statistically significant difference. Combination of the adjusted study-specific estimates into the random effects model showed a higher mean peak log2-titer in men compared with women (absolute difference [men-women]: 0.32, 95% CI: 0.02-.60). Fixed effects models controlling for study showed a similar result (log2 ELISA titer, men-women: 0.34, 95% CI: 0.04–0.63). This equates to a geometric mean peak titer that is approximately 27% higher in men than women (95% CI:3%–55%). Peak log2 PRNT titers were also higher (although not significantly) in men (men-women: 0.14, 95% CI: −0.30–0.58). Conclusion Our results show statistically significant differences in response to IMVAMUNE comparing healthy, vaccinia-naïve men with women and suggest that sex should be considered in further development and deployment of IMVAMUNE and other MVA
Goldblatt, David; Ramakrishnan, Meena; O'Brien, Katherine
An international consultation was convened in March 2012 to provide feedback on the Case for Carriage, a summary statement by the Pneumococcal Carriage Consortium (PneumoCarr) proposing nasopharyngeal (NP) colonization as a supplementary or alternative endpoint in vaccine licensure. PneumoCarr members provided information to vaccine manufacturers, regulators and the WHO on the evidence for NP carriage as a precursor to pneumococcal disease, standardization of laboratory methods for the detection of multiple serotype carriage, definition and estimation of pneumococcal vaccine efficacy against carriage (VE-col), and the direct and indirect impact of vaccination on carriage. Manufacturers and regulators had the opportunity to respond to the information compiled by PneumoCarr and share their perspectives. VE-col as a licensure endpoint may be more useful for the next generation pneumococcal vaccine products, particularly those for which the immunological correlate of protection is not established, whereas it may be less needed for pneumococcal conjugate vaccines which have an established licensure pathway. The consultation supported the importance of NP carriage data as a critical element linking vaccine impact on the individual direct risk of disease to the population-level impact: indirect effects such as herd protection and serotype replacement. The indirect effects of vaccination, however, are not currently established as part of the licensure process and to include them would be a paradigm shift for regulatory agencies who currently consider this information in the post-licensure setting. More discussion and consensus-building is needed around the rationale and optimal mechanism to include carriage data in the licensure pathway for new pneumococcal vaccines. The WHO and national advisory groups on immunization policy may have an important role in considering the evidence for the indirect benefit of vaccination as informed by its impact on NP carriage.
The use of foster children as subjects in the pediatric HIV/AIDS clinical trials has been the subject of media controversy, raising a range of ethical and social dimensions. Several unsettled issues and debates in research ethics underlie the controversy and the lack of consensus among professional researchers on these issues was neither adequately appreciated nor presented in media reports. These issues include (1) the tension between protecting subjects from research risk while allowing them access to the possible benefits of research; (2) the blurring of the potentially conflicting roles of investigator and physician and the boundaries between research and therapy; (3) the adequacy of Institutional Review Board oversight; and (4) trust and the relationships among physicians, investigators and industry. The media controversy about the pediatric HIV/AIDS clinical trials can be seen as a means of "manufacturing mistrust" in health care, research and social services that have not always met the needs and expectations of the public. In an era of emerging infections, it is critical to the public's health that people understand the role of rigorous and ethical research in the development of safe and effective care. Investigators, journalists and the public need to become knowledgeable about major ethical issues in the conduct of research in order to engage in dialogue about balancing research risks and benefits and to be able to distinguish fact from distortion in an era of multiple and rapid transmission of information.
Angwenyi, Vibian; Kamuya, Dorcas; Mwachiro, Dorothy; Marsh, Vicki; Njuguna, Patricia; Molyneux, Sassy
Community engagement is increasingly emphasized in biomedical research, as a right in itself, and to strengthen ethical practice. We draw on interviews and observations to consider the practical and ethical implications of involving Community Health Workers (CHWs) as part of a community engagement strategy for a vaccine trial on the Kenyan Coast. CHWs were initially engaged as an important network to be informed about the trial. However over time, and in response to community advice, they became involved in trial information sharing and identifying potential participants; thereby taking on roles that overlapped with those of employed fieldworkers (FWs). While CHWs involvement was generally perceived as positive and appreciated, there were challenges in their relations with FWs and other community members, partly related to levels and forms of remuneration. Specifically, payment of CHWs was not as high as for FWs and was based on 'performance'. This extrinsic motivation had the potential to crowd out CHWs intrinsic motivation to perform their pre-existing community roles. CHWs remuneration potentially also contributed to CHWs distorting trial information to encourage community members to participate; and to researchers encouraging CHWs to utilize their social connections and status to increase the numbers of people who attended information giving sessions. Individual consent processes were protected in this trial through final information sharing and consent being conducted by trained clinical staff who were not embedded in study communities. However, our experiences suggest that roles and remuneration of all front line staff and volunteers involved in trials need careful consideration from the outset, and monitoring and discussion over time.
Čečetková, B; Smetana, J; Chlíbek, R
Clinical trials are an important part of clinical research. The conduction of clinical trials is strictly regulated and has to comply with an approved protocol. Local regulatory authorities, independent ethic committees, sponsors of clinical trials as well as the investigators are involved from the submission until the very end of the trial. All clinical trials performed in the Czech Republic have to be approved by the State Institute for Drug Control and by the Ethics Committee. The regulatory bodies and independent ethics committees evaluate and continuously supervise the justification and protocol of the clinical trial, quality of the investigational medicinal products and, primarily, the safety of the participants (patients and/or healthy volunteers) in clinical trials. In the Czech Republic there are many advanced clinical research centres, either located in private practices or within hospitals. The investigators are able to conduct a wide variety of clinical trials and recruit a high number of subjects for the trials, as well as to comply with the Good Clinical Practice guidelines and other regulatory requirements. The aim of this article is to summarise the current situation of clinical trials in the Czech Republic as well as the opportunities for getting involved in clinical trials and obligations arising for health professionals from such an involvement.
Boué, Franck; Demerson, Jean Michel; Fassi Fihri, Ouafaa; Yahia, Khadija Id Sidi; Cliquet, Florence
Purpose Canine rabies is a serious health problem in Morocco and about 22 human deaths are reported yearly. Following the World Health Organization (WHO) recommendations, Moroccan authorities evaluated oral rabies vaccine baits specially designed for dogs. Materials and Methods The study was performed in Tiflet area. The vaccine strain was SAG2, a modified live oral rabies vaccine strain. Each bait contained an aluminium/PVC capsule filled with a liquid. Two kinds of baits were used: placebo baits containing methylene blue as a topical marker and vaccine baits containing vaccine suspension. The study was performed according to recommended WHO strategies, i.e., door to door model (DDDM), hand-out and wildlife immunization model (WIM). The DDDM was performed in the rural area of Tiflet on 60 owned dogs. The hand-out strategy was tested on 15 stray dogs. The WIM was performed on 4 transects lines near Tiflet slaughterhouse and near the weekly traditional market location. Results Using the DDDM, 100% of owned dogs were attracted by the baits and 77% ate the bait. Using the hand-out model, 100% of dogs showed interest in baits and 46.7% took the baits. Using the WIM in stray dogs, up to 73% of baits disappeared and 68% of the capsules containing the SAG2 vaccine were found pierced, depending on the sites of distribution. Conclusion This pilot study showed that baits have a good palatability and that oral vaccination of both owned and stray dogs is feasible with baits specifically developed for dogs and with adapted strategy of distribution. PMID:25003096
Lin, Chyongchiou Jeng; Zimmerman, Richard K; Nowalk, Mary Patricia; Huang, Hsin-Hui; Raviotta, Jonathan M.
Background Quadrivalent human papillomavirus (HPV) vaccine, for protection against sexually transmitted HPV infection, is licensed for females and males 9–26 years on a 3-dose schedule (0, 2, and 6 months; Standard schedule). Vaccine uptake has been low and catch-up vaccination of older adolescents using an alternate dosing schedule may increase coverage. This study tested the non-inferiority of the immunogenicity of an alternate dosing schedule (0, 2, 12 months) among college age males. Methods 220 18–25 year old males were randomly assigned to Standard or Alternate schedules. Blood samples were drawn immediately before Dose 1 and 2–6 weeks after Dose 3 and analyzed for antibody titers using a Luminex immunoassay. A value <1.5 for the upper 95% confidence interval (CI) bound of the Standard to Alternate schedule geometric mean titer (GMT) ratio was deemed non-inferior. Results Participants averaged 21.3 years old; 19.1% were non-white; completion rate was 93%. The anti-HPV titers for the Alternate schedule group were non-inferior to those of Standard schedule group for all four HPV vaccine virus types. Our results also demonstrated superiority of the Alternate schedule group for all four HPV vaccine virus types. Conclusion A delayed third dose at 12 months is immunologically non-inferior and superior for four HPV virus types. Using an alternate dosing schedule offers more flexibility to receive the 3-dose HPV vaccine and may result in higher vaccination rates among college-age males. PMID:24342252
Sadlier, C; O'Dea, S; Bennett, K; Dunne, J; Conlon, N; Bergin, C
The aim of this study was to compare the immunologic response to a prime-boost immunization strategy combining the 13-valent conjugate pneumococcal vaccine (PCV13) with the 23-valent polysaccharide pneumococcal vaccine (PPSV23) versus the PPSV23 alone in HIV-infected adults. HIV-infected adults were randomized to receive PCV13 at week 0 followed by PPSV23 at week 4 (n = 31, prime-boost group) or PPSV23 alone at week 4 (n = 33, PPSV23-alone group). Serotype specific IgG geometric mean concentration (GMC) and functional oposonophagocytic (OPA) geometric mean titer (GMT) were compared for 12 pneumococcal serotypes shared by both vaccines at week 8 and week 28. The prime-boost vaccine group were more likely to achieve a ≥2-fold increase in IgG GMC and a GMC >1 ug/ml at week 8 (odds ratio (OR) 2.00, 95% confidence interval (CI) 1.46-2.74, p < 0.01) and week 28 (OR 1.95, 95% CI 1.40-2.70, p < 0.01). Similarly, the prime-boost vaccine group were more likely to achieve a ≥4-fold increase in GMT at week 8 (OR 1.71, 95% CI 1.22-2.39, p < 0.01) and week 28 (OR 1.6, 95% CI 1.15-2.3, p < 0.01). This study adds to evidence supporting current pneumococcal vaccination recommendations combining the conjugate and polysaccharide pneumococcal vaccines in the United States and Europe for HIV-infected individuals.
Translating comparative effectiveness of depression medications into practice by comparing the depression medication choice decision aid to usual care: study protocol for a randomized controlled trial
Background Comparative effectiveness research (CER) documents important differences in antidepressants in terms of efficacy, safety, cost, and burden to the patient. Decision aids can adapt this evidence to help patients participate in making informed choices. In turn, antidepressant therapy will more likely reflect patients’ values and context, leading to improved adherence and mood outcomes. Methods/Design The objective of this study is to develop the Depression Medication Choice decision aid for use during primary care encounters, and to test its efficacy by conducting a clustered practical randomized trial comparing the decision aid to usual depression care in primary care practices. We will use a novel practice-based, patient-centered approach based on participatory action research that involves a multidisciplinary team of designers, investigators, clinicians, patient representatives, and other stakeholders for the development of the decision aid. We will then conduct a clustered practical randomized trial enrolling clinicians and their patients (n = 300) with moderate to severe depression from rural, suburban and inner city primary care practices (n = 10). The intervention will consist of the use of the depression medication choice decision aid during the clinical encounter. This trial will generate preliminary evidence of the relative impact of the decision aid on patient involvement in decision making, decision making quality, patient knowledge, and 6-month measures of medication adherence and mental health compared to usual depression care. Discussion Upon completion of the proposed research, we will have developed and evaluated the efficacy of the decision aid depression medication choice as a novel translational tool for CER in depression treatment, engaged patients with depression in their care, and refined the process by which we conduct practice-based trials with limited research footprint. Trial registration Clinical Trials.gov: NCT01502891 PMID
Mateus-Pinilla, N E; Dubey, J P; Choromanski, L; Weigel, R M
A 3-yr field trial was conducted on 8 commercial swine farms in Illinois to determine the effectiveness of a feline Toxoplasma gondii vaccine in reducing the exposure of swine to T. gondii. A vaccine consisting of live bradyzoites of the mutant T-263 strain, capable of preventing oocyst shedding by cats, was used in this study. Each farm was visited 3 times in 1994, 3 times in 1995, and once in 1996. Cats were trapped and inoculated with the T-263 oral vaccine during 1994 and 1995. On each visit, the following samples were collected: blood from pigs, cats, and mice for detection of serum antibodies to T. gondii, feces from cats to detect oocysts, and heart and brain tissues from rodents to determine the presence of T. gondii tissue cysts. The modified agglutination test (MAT), with a positive titer set at the 1:25 dilution, was used to determine serum antibodies. At first capture, 72.6% (61/84) of juvenile cats and 32.6% (31/95) of adult cats had no detectable antibodies (seronegative), indicating no prior exposure to T. gondii when they received their first vaccine. Of these first-time seronegative cats, 58.1% (18/31) of adult and 45.9% (28/61) of juvenile cats were recaptured and received a second dose of vaccine. Changes in the prevalence of T. gondii infection were evaluated from the prevaccination (1992, 1993) to the postvaccination (1996) period. Eleven cats (5%) were detected shedding oocysts between 1994 and 1996, of which 10 (90.1%) shed during 1994. The last detection of oocyst shedding by cats was during the first farm visit in 1995. There was a significant decrease in T. gondii seroprevalence for finishing pigs (P < 0.05, Wilcoxon sign rank test). There was a positive correlation (Spearman's p = 1.0, P < 0.0001) between the change in prevalence in juvenile cats and the change in prevalence in finishing pigs. The seropositivity rate (MAT > or = 1:25) in mice among all farms decreased from 4% in 1992-1993 to 0% in 1996. The mean prevalence of T. gondii
Etcheverry, M. Florencia; Evans, Jennifer L.; Sanchez, Emilia; Mendez-Arancibia, Eva; Meroño, Mercé; Gatell, José M.; Page, Kimberly; Joseph, Joan
The potential for implementation of HIV vaccine trials in hard-to-reach female sex workers in an inner city area of Barcelona, Spain was assessed via a study of HIV risk, willingness to participate and the success of retention strategies. In 130 women, serological HIV status, behavioral risk exposures and willingness to participate in future HIV vaccine trials were recorded every six months using a confidential questionnaire. An enhanced retention (ER) strategy was compared with a control retention (CR) strategy comprising the recording of data on appointment cards. HIV seroincidence and retention rates were estimated. Retention rates after 6 and 12 mo of follow-up in the ER group were 76% and 69% respectively compared with 16% and 13% in the CR group. Among the ER group 97% were willing to participate in HIV vaccine trials at baseline and, after 12 mo of follow-up. Willingness was significantly associated with higher HIV risk exposure, and higher education level. Successfully retaining these cohorts over time in settings with a high HIV seroincidence rate is an ongoing challenge that will need to be addressed to ensure participation in future trials. Furthermore, as we have demonstrated, the fact that retaining hard-to-reach populations is difficult should not exclude this target population for HIV vaccine and prevention trials. PMID:23291931
Van Der Meeren, Olivier; Peterson, James T.; Dionne, Marc; Beasley, Richard; Ebeling, Peter R.; Ferguson, Murdo; Nissen, Michael D.; Rheault, Paul; Simpson, Richard W.; De Ridder, Marc; Crasta, Priya D.; Miller, Jacqueline M.; Trofa, Andrew F.
ABSTRACT Objective: Patients with diabetes mellitus are at increased risk for hepatitis B virus (HBV) infection and its complications. HBV vaccination is recommended for adults with diabetes in the United States and other countries. However, few studies have assessed safety and immunogenicity of hepatitis B vaccine in such patients. We assessed the safety and immunogenicity of recombinant hepatitis B vaccine in subjects with and without diabetes mellitus. Methods: Prospective, multi-country controlled study in 21 centers (www.clinicaltrials.gov NCT01627340). Four hundred and sixteen participants with Type-2 diabetes and 258 controls matched for age and body mass index (BMI) (2:1 ratio) received 3-doses of HBV vaccine (Engerix-B™, GSK Vaccines, Belgium) according to a 0, 1, 6 months schedule. Antibodies were measured against HBV surface antigen and expressed as seroprotection rates (anti-HBs ≥10mIU/mL) and geometric mean concentration (GMC). Results: The median age and BMI in patients with diabetes and controls (according-to-protocol cohort) were 54 y and 32.1 kg/m2, and 53 y and 30.8 kg/m2, respectively. Seroprotection rates (GMCs) one month post-dose-3 were 75.4% (147.6 mIU/mL) and 82.0% (384.2 mIU/mL) in patients with diabetes and controls, respectively. Age-stratified seroprotection rates for patients with diabetes were 88.5% (20–39 years), 81.2% (40–49 years), 83.2% (50–59 years), and 58.2% (≥60 years). The overall safety profile of hepatitis B vaccine was similar between groups. Conclusions: Hepatitis B vaccine is immunogenic in patients with diabetes and has a similar safety profile to vaccination in healthy controls. Because increasing age was generally associated with a reduction in seroprotection rates, hepatitis B vaccine should be administered as soon as possible after the diagnosis of diabetes. PMID:27123743
Sandhu, J.S. . Div. of Immunology and Neurobiology)
The limitations of human vaccines in use at present and the design requirements for a new generation of human vaccines are discussed. The progress in engineering of human vaccines for bacteria, viruses, parasites, and cancer is reviewed, and the data from human studies with the engineered vaccines are discussed, especially for cancer and AIDS vaccines. The final section of the review deals with the possible future developments in the field of engineered human vaccines and the requirement for effective new human adjuvants.
Tsurudome, Yukari; Kimachi, Kazuhiko; Okada, Yusuke; Matsuura, Kenta; Ooyama, Yusuke; Ibaragi, Kayo; Kino, Yoichiro; Ueda, Kohji
Two antigenically distinct B strain lineages of influenza virus have co-circulated since the mid-1980s; however, inactivated trivalent influenza vaccines contain only one B lineage. The mismatch between the circulating and vaccine lineages has been a worldwide issue. In this study, an inactivated quadrivalent influenza vaccine (QIV) candidate containing two B lineages was manufactured and its immunogenicity and safety evaluated in an open-label, uncontrolled trial. In this phase II trial, 50 subjects aged 20-64 years received two doses of QIV s.c. 1 to 4 weeks apart. Sera were collected pre- and post-vaccination and safety assessed from the first vaccination to 21 ± 7 days after the second vaccination. After the first vaccination, hemagglutination inhibition titers against each strain increased markedly; the seroconversion rate, geometric mean titer ratio and seroprotection rate being 94.0%, 24.93, and 100.0%, respectively, for the A/H1N1pdm09 strain; 94.0%, 12.47, and 98.0%, respectively, for the A/H3N2 strain; 54.0%, 4.99, and 66.0%, respectively, for B/Yamagata strain, and 72.0%, 6.23 and 80.0%, respectively, for the B/Victoria strain, thus fulfilling the criteria of the European Medical Agency's Committee for Medicinal Products for Human Use. Also, the QIV induced sufficient single radial hemolysis and neutralizing antibodies against all four vaccine strains. No noteworthy adverse events were noted. The results of this trial demonstrate that QIV is well tolerated and immunogenic for each strain, suggesting that QIV potentially improves protection against influenza B by resolving the issue of B lineage mismatch.
Easterhoff, David; Moody, M Anthony; Fera, Daniela; Cheng, Hao; Ackerman, Margaret; Wiehe, Kevin; Saunders, Kevin O; Pollara, Justin; Vandergrift, Nathan; Parks, Rob; Kim, Jerome; Michael, Nelson L; O'Connell, Robert J; Excler, Jean-Louis; Robb, Merlin L; Vasan, Sandhya; Rerks-Ngarm, Supachai; Kaewkungwal, Jaranit; Pitisuttithum, Punnee; Nitayaphan, Sorachai; Sinangil, Faruk; Tartaglia, James; Phogat, Sanjay; Kepler, Thomas B; Alam, S Munir; Liao, Hua-Xin; Ferrari, Guido; Seaman, Michael S; Montefiori, David C; Tomaras, Georgia D; Harrison, Stephen C; Haynes, Barton F
The canary pox vector and gp120 vaccine (ALVAC-HIV and AIDSVAX B/E gp120) in the RV144 HIV-1 vaccine trial conferred an estimated 31% vaccine efficacy. Although the vaccine Env AE.A244 gp120 is antigenic for the unmutated common ancestor of V1V2 broadly neutralizing antibody (bnAbs), no plasma bnAb activity was induced. The RV305 (NCT01435135) HIV-1 clinical trial was a placebo-controlled randomized double-blinded study that assessed the safety and efficacy of vaccine boosting on B cell repertoires. HIV-1-uninfected RV144 vaccine recipients were reimmunized 6-8 years later with AIDSVAX B/E gp120 alone, ALVAC-HIV alone, or a combination of ALVAC-HIV and AIDSVAX B/E gp120 in the RV305 trial. Env-specific post-RV144 and RV305 boost memory B cell VH mutation frequencies increased from 2.9% post-RV144 to 6.7% post-RV305. The vaccine was well tolerated with no adverse events reports. While post-boost plasma did not have bnAb activity, the vaccine boosts expanded a pool of envelope CD4 binding site (bs)-reactive memory B cells with long third heavy chain complementarity determining regions (HCDR3) whose germline precursors and affinity matured B cell clonal lineage members neutralized the HIV-1 CRF01 AE tier 2 (difficult to neutralize) primary isolate, CNE8. Electron microscopy of two of these antibodies bound with near-native gp140 trimers showed that they recognized an open conformation of the Env trimer. Although late boosting of RV144 vaccinees expanded a novel pool of neutralizing B cell clonal lineages, we hypothesize that boosts with stably closed trimers would be necessary to elicit antibodies with greater breadth of tier 2 HIV-1 strains.
Henning, J; Morton, J; Pym, R; Hla, T; Meers, J
Previous research identified Newcastle disease and poor management of chicks (birds younger than 6 weeks of age) as major constraints to village chicken production in Myanmar. Based on these findings, controlled trials were conducted in 124 randomly selected households in nine villages in Myanmar over a period of 12 months to evaluate strategies to enhance survival of village chickens. Two intervention strategies were assessed: Newcastle disease vaccination using the thermostable I-2 vaccine and changes to the management of chick rearing (confinement and supplementary feeding). These interventions were applied in two trials: (1) a randomised controlled trial to compare I-2 vaccination, altered chick management and no intervention (apart from placebo treatment) at household level and (2) nested within this trial, a double-blinded controlled trial at bird-level to compare serological titres between I-2 vaccinated and placebo-treated birds both between and within households. Outcomes measured in the first trial were crude incidence rate of mortality, proportional mortality rate for deaths due to disease stratified by age group of birds and mortality attributed to Newcastle disease, number of sales, income from sale of birds, consumption of birds and hatching of birds. Odds of having protective titres two weeks after vaccination were up to 125 times higher in I-2 vaccinated birds and up to 47 times higher in control birds in contact with I-2 vaccinates compared to birds without I-2 contact. Vaccination against Newcastle disease reduced the proportions of mortalities assumed to be caused by disease in growers and chicks. Crude mortality incidence was lower in households that applied management changes to chick rearing. In household-months when birds were sold, numbers sold were higher and income from sale of birds were about 2.50 US dollars per month higher in households allocated to altered chick management. Altered chick management resulted in more households having
Spearman, Paul; Kalams, Spyros; Elizaga, Marnie; Metch, Barbara; Chiu, Ya-Lin; Allen, Mary; Weinhold, Kent J; Ferrari, Guido; Parker, Scott D; McElrath, M Juliana; Frey, Sharon E; Fuchs, Jonathan D; Keefer, Michael C; Lubeck, Michael D; Egan, Michael; Braun, Ralph; Eldridge, John H; Haynes, Barton F; Corey, Lawrence
There is an urgent need for a vaccine capable of preventing HIV infection or the development of HIV-related disease. A number of approaches designed to stimulate HIV-specific CD8+ cytotoxic T cell responses together with helper responses are presently under evaluation. In this phase 1, multi-center, placebo-controlled trial, we tested the ability of a novel multiepitope peptide vaccine to elicit HIV-specific immunity. To enhance the immunogenicity of the peptide vaccine, half of the vaccine recipients received recombinant granulocyte-macrophage colony stimulating factor (GM-CSF) protein as a coadjuvant. The vaccine was safe; tolerability was moderate, with a number of adverse events related to local injection site reactogenicity. Anti-GM-CSF antibody responses developed in the majority of GM-CSF recipients but were not associated with adverse hematologic events. The vaccine was only minimally immunogenic. Six of 80 volunteers who received vaccine developed HIV-specific responses as measured by interferon-gamma ELISPOT assay, and measurable responses were transient. This study failed to demonstrate that GM-CSF can substantially improve the overall weak immunogenicity of a multiepitope peptide-based HIV vaccine.
Artnzen, C J
Vaccines were the result of trial and error research until molecular biology and genetic engineering made possible the creation of of many new and improved vaccines. New vaccines need to be inexpensive, easily administered, and capable of being stored and transported without refrigeration; without these characteristics, developing countries find it difficult to adopt vaccination as the central strategy for preventing their most devastating diseases. The authors describe a promising approach to inexpensive and effective vaccines: producing them in plants we commonly consume. Images p190-a p191-a p193-a p196-a PMID:9182305
Robbins, Gregory K.; Spritzler, John G.; Chan, Ellen S.; Asmuth, David M.; Gandhi, Rajesh T.; Rodriguez, Benigno A.; Skowron, Gail; Skolnik, Paul R.; Shafer, Robert W.; Pollard, Richard B.
Background Initiation of combination antiretroviral therapy (ART) results in higher total CD4 cell counts, a surrogate for immune reconstitution. Whether the baseline CD4 cell count affects reconstitution of immune cell subsets has not been well characterized. Methods Using data from 978 patients (621 with comprehensive immunological assessments) from the AIDS [Acquired Immunodeficiency Syndrome] Clinical Trials Group protocol 384, a randomized trial of initial ART, we compared reconstitution of CD4+, CD4+ naive and memory, CD4+ activation, CD8+, CD8+ activation, B, and natural killer cells among patients in different baseline CD4+ strata. Reference ranges for T cell populations in control patients negative for human immunodeficiency virus (HIV) infection were calculated using data from AIDS Clinical Trials Group protocol A5113. Results Patients in the lower baseline CD4+ strata did not achieve total CD4+ cell counts similar to those of patients in the higher strata during 144 weeks of ART, although CD4+ cell count increases were similar. Ratios of CD4+ naive-memory cell counts and CD4+:CD8+ cell counts remained significantly reduced in patients with lower baseline CD4+ cell counts (≤350 cells/mm3). These immune imbalances were most notable for those initiating ART with a baseline CD4+ cell count ≤200 cells/mm3, even after adjustment for baseline plasma HIV RNA levels. Conclusions After nearly 3 years of ART, T cell subsets in patients with baseline CD4+ cell counts >350 cells/mm3 achieved or approached the reference range those of control individuals without HIV infection. In contrast, patients who began ART with ≤350 CD4+ cells/mm3 generally did not regain normal CD4+ naive-memory cell ratios. These results support current guidelines to start ART at a threshold of 350 cells/mm3 and suggest that there may be immunological benefits associated with initiating therapy at even higher CD4+ cell counts. PMID:19123865
Nyamathi, Adeline; Salem, Benissa E.; Zhang, Sheldon; Farabee, David; Hall, Betsy; Khalilifard, Farinaz; Leake, Barbara
Background Although hepatitis A virus (HAV) and hepatitis B virus (HBV) infections are vaccine-preventable diseases, few homeless parolees coming out of prisons and jails have received the hepatitis A and B vaccination series. Objectives The study focused on completion of the HAV and HBV vaccine series among homeless men on parole. The efficacy of three levels of peer coaching and nurse-delivered interventions was compared at 12-month follow up: (a) intensive peer coaching and nurse case management (PC-NCM); (b) intensive peer coaching (PC) intervention condition, with minimal nurse involvement; and a (c) usual care (UC) intervention condition, which included minimal PC and nurse involvement. Further, we assessed predictors of vaccine completion among this targeted sample. Methods A randomized control trial was conducted with 600 recently paroled men to assess the impact of the three intervention conditions (PC-NCM vs. PC vs. UC) on reducing drug use and recidivism; of these, 345 seronegative, vaccine-eligible subjects were included in this analysis of completion of the Twinrix HAV/HAB vaccine. Logistic regression was added to assess predictors of completion of the HAV/HBV vaccine series and chi-squared analysis to compare completion rates across the three levels of intervention. Results Vaccine completion rate for the intervention conditions were 75.4% (PC-NCM), 71.8% (PC), and 71.9% (UC) (p =. 78). Predictors of vaccine noncompletion included being Asian and Pacific Islander, experiencing high levels of hostility, positive social support, reporting a history of injection drug use, being released early from California prisons, and being admitted for psychiatric illness. Predictors of vaccine series completion included reporting six or more friends, recent cocaine use, and staying in drug treatment for at least 90 days. Discussion Findings allow greater understanding of factors affecting vaccination completion in order to design more effective programs among the
Parra, L E; Borja-Cabrera, G P; Santos, F N; Souza, L O P; Palatnik-de-Sousa, C B; Menz, I
A group of 600 healthy and asymptomatic dogs from Brazilian canine visceral leishmaniasis endemic areas was vaccinated with three sc doses of Leishmune which is the industrialized formulation of the FML-saponin, recently licensed for commercialization in Brazil, which previously showed 76-80% vaccine efficacy against canine visceral leishmaniasis. Safety evaluation was performed for 14 days after each vaccine injection and disclosed transient reactions of local pain (40.87%), anorexia (20.48%), apathy (24.17%), local swelling reactions (15.90%), vomit (2.4%) and diarrhoea (1.5%). All effects showed significantly correlating declines, from the first to the third dose (p<0.0001). Most of the noticed reactions of pain (73%), anorexia (79%) and local swelling (84.7%) were mild. No significant differences between puppies and adults dogs were found in the number of adverse reactions. Adult dogs developed however, 94.5% of the small swelling reactions (<3 cm), and indicating that they are more resistant to the inflammatory response promoted by the saponins. No dead by anaphylaxis occurred, and only two dogs (0.1%) showed allergic reactions (facial oedema and itching) after the third dose. Transient alopecia on injection site occurred in only five poodles (0.28%) with total recovery and no need of treatment. All the mild adverse events in response to Leishmune injection were transient and disappeared before the injection of the following vaccine dose, confirming the tolerability of the vaccine. The Leishmune preparation was less haemolytic (HD(50)=180 microg/ml) than expected for a QS21 saponin-containing vaccine, indicating that its formulation with the FML antigen diminished the potential in vitro toxicity.
McCormack, William M.; Rahman, A. S. M. Mizanur; Chowdhury, A. K. M. Alauddin; Mosley, Wiley H.; Phillips, Robert A.
In a controlled study, it has been shown that the prior administration of cholera vaccine had no beneficial effect on the clinical course of cholera as measured by either the condition of the patient on admission to hospital or the subsequent course of the disease. In fact, the disease was, if anything, more severe in those who had received cholera vaccine. Although the presence of a high vibriocidal titre is associated with protection from cholera, pre-existing antibody had no effect on the clinical course of the disease in those patients who developed cholera. PMID:5306540
Rappuoli, Rino; Aderem, Alan
Acquired immune deficiency syndrome (AIDS), malaria and tuberculosis collectively cause more than five million deaths per year, but have nonetheless eluded conventional vaccine development; for this reason they represent one of the major global public health challenges as we enter the second decade of the twenty-first century. Recent trials have provided evidence that it is possible to develop vaccines that can prevent infection by human immunodeficiency virus (HIV) and malaria. Furthermore, advances in vaccinology, including novel adjuvants, prime-boost regimes and strategies for intracellular antigen presentation, have led to progress in developing a vaccine against tuberculosis. Here we discuss these advances and suggest that new tools such as systems biology and structure-based antigen design will lead to a deeper understanding of mechanisms of protection which, in turn, will lead to rational vaccine development. We also argue that new and innovative approaches to clinical trials will accelerate the availability of these vaccines.
Bennett, Jason W.; Yadava, Anjali; Tosh, Donna; Sattabongkot, Jetsumon; Komisar, Jack; Ware, Lisa A.; McCarthy, William F.; Cowden, Jessica J.; Regules, Jason; Spring, Michele D.; Paolino, Kristopher; Hartzell, Joshua D.; Cummings, James F.; Richie, Thomas L.; Lumsden, Joanne; Kamau, Edwin; Murphy, Jittawadee; Lee, Cynthia; Parekh, Falgunee; Birkett, Ashley; Cohen, Joe; Ballou, W. Ripley; Polhemus, Mark E.; Vanloubbeeck, Yannick F.; Vekemans, Johan; Ockenhouse, Christian F.
Background A vaccine to prevent infection and disease caused by Plasmodium vivax is needed both to reduce the morbidity caused by this parasite and as a key component in efforts to eradicate malaria worldwide. Vivax malaria protein 1 (VMP001), a novel chimeric protein that incorporates the amino- and carboxy- terminal regions of the circumsporozoite protein (CSP) and a truncated repeat region that contains repeat sequences from both the VK210 (type 1) and the VK247 (type 2) parasites, was developed as a vaccine candidate for global use. Methods We conducted a first-in-human Phase 1 dose escalation vaccine study with controlled human malaria infection (CHMI) of VMP001 formulated in the GSK Adjuvant System AS01B. A total of 30 volunteers divided into 3 groups (10 per group) were given 3 intramuscular injections of 15μg, 30μg, or 60μg respectively of VMP001, all formulated in 500μL of AS01B at each immunization. All vaccinated volunteers participated in a P. vivax CHMI 14 days following the third immunization. Six non-vaccinated subjects served as infectivity controls. Results The vaccine was shown to be well tolerated and immunogenic. All volunteers generated robust humoral and cellular immune responses to the vaccine antigen. Vaccination did not induce sterile protection; however, a small but significant delay in time to parasitemia was seen in 59% of vaccinated subjects compared to the control group. An association was identified between levels of anti-type 1 repeat antibodies and prepatent period. Significance This trial was the first to assess the efficacy of a P. vivax CSP vaccine candidate by CHMI. The association of type 1 repeat-specific antibody responses with delay in the prepatency period suggests that augmenting the immune responses to this domain may improve strain-specific vaccine efficacy. The availability of a P. vivax CHMI model will accelerate the process of P. vivax vaccine development, allowing better selection of candidate vaccines for
Szmuness, W; Stevens, C E; Harley, E J; Zang, E A; Oleszko, W R; William, D C; Sadovsky, R; Morrison, J M; Kellner, A
We assessed the efficacy of an inactivated hepatitis B vaccine in a placebo-controlled, randomized, double-blind trial in 1083 homosexual men known to be at high risk for hepatitis B virus infection. The vaccine was found to be safe and the incidence of side effects was low. Within two months, 77% of the vaccinated persons had high levels of antibody against the hepatitis B surface antigen. This rate increased to 96% after the booster dose and remained essentially unchanged for the duration of the trial. For the first 18 months of follow-up, hepatitis B or subclinical infection developed in only 1.4 to 3.4% of the vaccine recipients as compared with 18 to 27% of placebo recipients (P < 0.0001). The reduction of incidence in the vaccinees was as high as 92.3%; none of the vaccinees with a detectable immune response to the vaccine had clinical hepatitis B or asymptomatic antigenemia. A significant reduction of incidence was already seen within 75 days after randomization; this observation suggests that the vaccine may be efficacious even when given after exposure.
Juergens, Christine; Ruiz Palacios, Guillermo M.; Vazquez-Narvaez, Jorge; Enkerlin-Pauwells, Hermann Leo; Sundaraiyer, Vani; Pathirana, Sudam; Kalinina, Elena; Gruber, William C.; Scott, Daniel A.; Schmoele-Thoma, Beate
This open-label multicenter clinical trial conducted in Mexico assessed the immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine (PCV13) in adults ≥50 years of age not previously vaccinated with the 23-valent pneumococcal polysaccharide vaccine (PPSV23). The PCV13 elicited a robust immune response in this study population, as reflected by the magnitude of fold rises in functional antibody levels measured by serotype-specific opsonophagocytic activity (OPA) assays before and 1 month after vaccination. Although the prevaccination OPA geometric mean titers (GMTs) for the majority of the serotypes were significantly lower in the 50- to 64-year age group than those in the ≥65-year age group, the postvaccination immune responses were generally similar. The overall immune responses were higher for the majority of the serotypes in the Mexican study population than those in similar adult study populations who received the PCV13 in Europe and the United States. PCV13 was well tolerated, and there were no vaccine-related serious adverse events. In conclusion, PCV13 is safe and immunogenic when administered to adults ≥50 years of age in Mexico and has the potential to protect against vaccine-type pneumococcal disease. (This study has been registered at ClinicalTrials.gov under registration no. NCT01432262.) PMID:25499011
Ali, Mohammad; Luquero, Francisco J.; Kim, Deok Ryun; Park, Je Yeon; Digilio, Laura; Manna, Byomkesh; Kanungo, Suman; Dutta, Shanta; Sur, Dipika; Bhattacharya, Sujit K.
Introduction Vaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy. Methods and Findings This analysis uses existing data from a cluster-randomized clinical trial in which OCV or placebo was given to 71,900 participants in Kolkata, India, from 27 July to 10 September 2006. Cholera surveillance was then conducted on 144,106 individuals living in the study area, including trial participants, for 5 y following vaccination. First, we explored the risk of cholera among contacts of cholera patients, and, second, we measured VE among individuals living within 25 m of cholera cases between 8 and 28 d after onset of the index case. For the first analysis, individuals living around each index case identified during the 5-y period were assembled using a ring to define cohorts of individuals exposed to cholera index cases. An index control without cholera was randomly selected for each index case from the same population, matched by age group, and individuals living around each index control were assembled using a ring to define cohorts not exposed to cholera cases. Cholera attack rates among the exposed and non-exposed cohorts were compared using different distances from the index case/control to define the rings and different time frames to define the period at risk. For the VE analysis, the exposed cohorts were further stratified according to the level of vaccine coverage into high and low coverage strata. Overall VE was assessed by comparing the attack rates between high and low vaccine coverage strata irrespective of individuals’ vaccination status, and indirect VE was assessed by comparing the attack rates among unvaccinated members between high and low vaccine coverage strata. Cholera risk among the cohort exposed to
Stein, James H.; Ribaudo, Heather J.; Hodis, Howard N.; Brown, Todd T.; Tran, Thuy Tien T.; Yan, Mingzhu; Brodell, Elizabeth Lauer; Kelesidis, Theodore; McComsey, Grace A.; Dube, Michael P.; Murphy, Robert L.; Currier, Judith S.
Objective This article compares the effects of initiating three contemporary antiretroviral therapy (ART) regimens on progression of carotid artery intima-media thickness (IMT) over 3 years. Design Randomized clinical trial. Setting Multicenter (26 institutions). Patients ART-naïve HIV-infected individuals (n = 328) without known cardiovascular disease or diabetes mellitus. Intervention Random assignment to tenofovir/emtricitabine along with atazanavir/ritonavir (ATV/r), darunavir/ritonavir (DRV/r), or raltegravir (RAL). Main outcome measures Right-sided carotid IMT was evaluated by B-mode ultra-sonography before ART initiation, and then after 48, 96, and 144 weeks. Comparisons of yearly rates of change in carotid IMT used mixed-effects linear regression models that permitted not only evaluation of the effects of ART on carotid IMT progression but also how ART-associated changes in traditional risk factors, bilirubin, and markers of HIV infection were associated carotid IMT progression. Results HIV-1 RNA suppression rates were high in all arms (>85%) over 144 weeks. Modest increases in triglycerides and non-high-density lipoprotein cholesterol levels were observed in the protease inhibitor containing arms compared with decreases with RAL. In contrast, carotid IMT progressed more slowly on ATV/r [8.2, 95% confidence interval (5.6, 10.8) μm/year] than DRV/r [12.9 (10.3, 15.5) μm/year, P = 0.013]; changes with RAL were intermediate [10.7 (9.2, 12.2) μm/year, P = 0.15 vs. ATV/r; P = 0.31 vs. DRV/r]. Bilirubin and non-high-density lipoprotein cholesterol levels appeared to influence carotid IMT progression rates. Conclusion In ART-naïve HIV-infected individuals at low cardiovascular disease risk, carotid IMT progressed more slowly in participants initiating ATV/r than those initiating DRV/r, with intermediate changes associated with RAL. This effect may be due, in part, to hyperbilirubinemia. PMID:26372383
Alexandrova, G I; Budilovsky, G N; Koval, T A; Polezhaev, F I; Garmashova, L M; Ghendon YuZ; Romanova, Y R; Smorodintsev, A A
Live cold-adapted recombinant bivalent vaccine of influenza type A was studied in a controlled field trial in 1982-1983 among nearly 30,000 children 3-15 years old. The bivalent vaccine consisted of recombinants 47/25/1 (H1N1) and 47/7/2 (H3N2) of wild-type viruses A/Brazil/11/78 (H1N1) and A/Bangkok/1/79 (H3N2) with cold-adapted donor A/Leningrad/134/47/57 (H2N2). The recombinants which received mutant nonglycoprotein genes from cold-adapted donor did not suppress each other after simultaneous inoculation of children and stimulated antibody response to both strains. The bivalent vaccine was completely attenuated for children. It caused less than 1% transient febrile reactions during five days after the first vaccination, including double seronegative individuals with low antibody titres to both vaccinal strains. The cold-adapted bivalent vaccine tested proved to be safe for children according to the analysis of morbidity studies among vaccines and a control group performed during the five days and the following six months after the first immunization. There is a similar distribution of non-influenza illnesses and a statistically significant decrease in influenza-like diseases among vaccines compared to the control group. In the four months after the immunization programme was completed, epidemics of influenza A H1N1 and H3N2 occurred. The incidence of influenza-like diseases was approximately 50% less in the vaccinated than in the control groups. This is the first evidence of safety and protective efficacy of recombinant live influenza vaccine for children 3-15 years of age.
Extended Follow-up Confirms Early Vaccine-Enhanced Risk of HIV Acquisition and Demonstrates Waning Effect Over Time Among Participants in a Randomized Trial of Recombinant Adenovirus HIV Vaccine (Step Study)
Duerr, Ann; Huang, Yunda; Buchbinder, Susan; Coombs, Robert W.; Sanchez, Jorge; del Rio, Carlos; Casapia, Martin; Santiago, Steven; Gilbert, Peter; Corey, Lawrence; Robertson, Michael N.
Background. The Step Study tested whether an adenovirus serotype 5 (Ad5)–vectored human immunodeficiency virus (HIV) vaccine could prevent HIV acquisition and/or reduce viral load set-point after infection. At the first interim analysis, nonefficacy criteria were met. Vaccinations were halted; participants were unblinded. In post hoc analyses, more HIV infections occurred in vaccinees vs placebo recipients in men who had Ad5-neutralizing antibodies and/or were uncircumcised. Follow-up was extended to assess relative risk of HIV acquisition in vaccinees vs placebo recipients over time. Methods. We used Cox proportional hazard models for analyses of vaccine effect on HIV acquisition and vaccine effect modifiers, and nonparametric and semiparametric methods for analysis of constancy of relative risk over time. Results. One hundred seventy-two of 1836 men were infected. The adjusted vaccinees vs placebo recipients hazard ratio (HR) for all follow-up time was 1.40 (95% confidence interval [CI], 1.03–1.92; P = .03). Vaccine effect differed by baseline Ad5 or circumcision status during first 18 months, but neither was significant for all follow-up time. The HR among uncircumcised and/or Ad5-seropositive men waned with time since vaccination. No significant vaccine-associated risk was seen among circumcised, Ad5-negative men (HR, 0.97; P = 1.0) over all follow-up time. Conclusions. The vaccine-associated risk seen in interim analysis was confirmed but waned with time from vaccination. Clinical Trials Registration. NCT00095576. PMID:22561365
Tamas, Ferenc; Jankovics, Istvan
With the recent pandemic of influenza A (H1N1) and vaccine shortages, there has been considerable interest in developing influenza vaccines with reduced doses, allowing for increased production capacity. Here we report a prospective, randomized, double-blind, single-center clinical trial of a reduced-dose whole-virion inactivated, adjuvanted influenza vaccine in adult and elderly volunteers. A total of 234 subjects, including 120 adults (18 to 60 years of age) and 114 elderly subjects (>60 years of age) were enrolled to receive either 6 μg or the conventional 15-μg dose of seasonal trivalent influenza vaccines. The subjects were followed for safety analysis, and serum samples were obtained to assess immunogenicity by hemagglutination inhibition testing. The subjects developed antibody responses against the seasonal influenza A virus H1N1 and H3N2 strains, as well as the seasonal influenza B virus included in the vaccines. Single doses of 6 μg fulfilled licensing criteria for seasonal influenza vaccines. No significant differences in rates of seroconversion or seroprotection or in geometric mean titers were found between the two dosage levels. All adverse events were rare, mild, and transient. We found that the present reduced-dose vaccine is safe and immunogenic in healthy adult and elderly subjects and triggers immune responses that comply with licensing criteria. PMID:22219315
Valero, M V; Amador, R; Aponte, J J; Narvaez, A; Galindo, C; Silva, Y; Rosas, J; Guzman, F; Patarroyo, M E
A double-blind randomized placebo-controlled field trial with the SPf66 malaria vaccine was carried out in an endemic area consisting of 14 small villages with exclusive fluvial access, in a rain forest area along the Rosario River, Colombia. A total of 1257 subjects completed the full three dose vaccination schedule on days 0, 30 and 180 (643 vaccinated group/623 placebo group) and were followed-up by passive and active surveillance over a period of 22 months. One hundred and thirty-four Plasmodium falciparum malaria episodes were detected (53 in vaccinated group/81 in placebo group), yielding an attack rate of 5.47 cases/100 person years of follow-up (pyears) in the vaccine group and 8.44/100 pyears in the placebo group. The estimated vaccine protective efficacy was 35.2% (95% CI 8.4-54.2%, P = 0.01). This result supports earlier findings that the SPf66 malaria vaccine diminishes the risk of infection by P. falciparum in endemic areas of South America.
Nyendak, Melissa; Swarbrick, Gwendolyn M.; Duncan, Amanda; Cansler, Meghan; Huff, Ervina Winata; Hokey, David; Evans, Tom; Barker, Lewellys; Blatner, Gretta; Sadoff, Jerald; Douoguih, Macaya; Pau, Maria Grazia; Lewinsohn, Deborah A.; Lewinsohn, David M.
The development of a vaccine for Mycobacterium tuberculosis (Mtb) has been impeded by the absence of correlates of protective immunity. One correlate would be the ability of cells induced by vaccination to recognize the Mtb-infected cell. AERAS-402 is a replication-deficient serotype 35 adenovirus containing DNA expressing a fusion protein of Mtb antigens 85A, 85B and TB10.4. We undertook a phase I double-blind, randomized placebo controlled trial of vaccination with AERAS-402 following BCG. Analysis of the vaccine-induced immune response revealed strong antigen-specific polyfunctional CD4+ and CD8+ T cell responses. However, analysis of the vaccine-induced CD8+ T cells revealed that in many instances these cells did not recognize the Mtb-infected cell. Our findings highlight the measurement of vaccine-induced, polyfunctional T cells may not reflect the extent or degree to which these cells are capable of identifying the Mtb-infected cell and correspondingly, the value of detailed experimental medicine studies early in vaccine development. PMID:27805026
Watanaveeradej, Veerachai; Gibbons, Robert V; Simasathien, Sriluck; Nisalak, Ananda; Jarman, Richard G; Kerdpanich, Angkool; Tournay, Elodie; De La Barrerra, Rafael; Dessy, Francis; Toussaint, Jean-François; Eckels, Kenneth H; Thomas, Stephen J; Innis, Bruce L
Safety and immunogenicity of two formulations of a live-attenuated tetravalent dengue virus (TDEN) vaccine produced using rederived master seeds from a precursor vaccine were tested against a placebo control in a phase II, randomized, double blind trial (NCT00370682). Two doses were administered 6 months apart to 120 healthy, predominantly flavivirus-primed adults (87.5% and 97.5% in the two vaccine groups and 92.5% in the placebo group). Symptoms and signs reported after vaccination were mild to moderate and transient. There were no vaccine-related serious adverse events or dengue cases reported. Asymptomatic, low-level viremia (dengue virus type 2 [DENV-2], DENV-3, or DENV-4) was detected in 5 of 80 vaccine recipients. One placebo recipient developed a subclinical natural DENV-1 infection. All flavivirus-unprimed subjects and at least 97.1% of flavivirus-primed subjects were seropositive to antibodies against all four DENV types 1 and 3 months post-TDEN dose 2. The TDEN vaccine was immunogenic with an acceptable safety profile in flavivirus-primed adults.
Griffith, Jennifer M; Lewis, Carmen L; Brenner, Alison RT; Pignone, Michael P
Background Decision aids can improve decision making processes, but the amount and type of information that they should attempt to communicate is controversial. We sought to compare, in a pilot randomized trial, two colorectal cancer (CRC) screening decision aids that differed in the number of screening options presented. Methods Adults ages 48–75 not currently up to date with screening were recruited from the community and randomized to view one of two versions of our previously tested CRC screening decision aid. The first version included five screening options: fecal occult blood test (FOBT), sigmoidoscopy, a combination of FOBT and sigmoidoscopy, colonoscopy, and barium enema. The second discussed only the two most frequently selected screening options, FOBT and colonoscopy. Main outcomes were differences in screening interest and test preferences between groups after decision aid viewing. Patient test preference was elicited first without any associated out-of-pocket costs (OPC), and then with the following costs: FOBT-$10, sigmoidoscopy-$50, barium enema-$50, and colonoscopy-$200. Results 62 adults participated: 25 viewed the 5-option decision aid, and 37 viewed the 2-option version. Mean age was 54 (range 48–72), 58% were women, 71% were White, 24% African-American; 58% had completed at least a 4-year college degree. Comparing participants that viewed the 5-option version with participants who viewed the 2-option version, there were no differences in screening interest after viewing (1.8 vs. 1.9, t-test p = 0.76). Those viewing the 2-option version were somewhat more likely to choose colonoscopy than those viewing the 5-option version when no out of pocket costs were assumed (68% vs. 46%, p = 0.11), but not when such costs were imposed (41% vs. 42%, p = 1.00). Conclusion The number of screening options available does not appear to have a large effect on interest in colorectal cancer screening. The effect of offering differing numbers of options may
Mamotte, Nicole; Wassenaar, Douglas; Singh, Nivedhna
Concern has been voiced in the research ethics literature that under U.S. federal regulations U.S. sponsors, particularly the NIH, are not required to provide compensation for the treatment of research-related injury for trial participants or to allow grant funds to be used by investigators for appropriate insurance. This is problematic in developing country contexts because most participants are unlikely to have health insurance, resulting in overburdened and under-resourced health systems in many developing countries being responsible for providing care and treatment for research-related injury. This study provides preliminary insight into how respondent principal investigators of NIH-sponsored HIV/AIDS clinical trials in Africa and African research ethics committees deal with compensation for research-related injury. The majority of PIs surveyed provided free treatment for research-related injury, but few provided other forms of financial reparation to participants. The study also found that half of the PIs surveyed indicated that NIH funds were used for compensation, highlighting a contradiction between literature and practice. The majority of REC chairs surveyed indicated that their RECs routinely reviewed compensation plans for research-related injury and that their ethics application forms specifically requested information on compensation. Findings from one southern African country revealed that NIH funds were not used to provide treatment and/or financial reparation for research-related injury. Instead, PIs from this country relied on the government or the individual research participant (and/or their medical aid/health insurer) to cover the costs of research-related injury. The findings are discussed in the light of the recent (December 2011) U.S. Presidential Commission for the Study of Bioethics report which recommends that research participants are morally entitled to compensation for research-related injury.
Constantino, João; Gomes, Célia; Falcão, Amílcar; Cruz, Maria T; Neves, Bruno M
Dendritic cells (DCs) are versatile elements of the immune system and are best known for their unparalleled ability to initiate and modulate adaptive immune responses. During the past few decades, DCs have been the subject of numerous studies seeking new immunotherapeutic strategies against cancer. Despite the initial enthusiasm, disappointing results from early studies raised some doubts regarding the true clinical value of these approaches. However, our expanding knowledge of DC immunobiology and the definition of the optimal characteristics for antitumor immune responses have allowed a more rational development of DC-based immunotherapies in recent years. Here, after a brief overview of DC immunobiology, we sought to systematize the knowledge provided by 20 years of clinical trials, with a special emphasis on the diversity of approaches used to manipulate DCs and their consequent impact on vaccine effectiveness. We also address how new therapeutic concepts, namely the combination of DC vaccines with other anticancer therapies, are being implemented and are leveraging clinical outcomes. Finally, optimization strategies, new insights, and future perspectives on the field are also highlighted.
Chakrapani, Venkatesan; Newman, Peter A.; Singhal, Neeti; Jerajani, Jhalak; Shunmugam, Murali
Background Recruitment of low- and middle-income country volunteers from most-at-risk populations in HIV vaccine trials is essential to vaccine development. In India, men who have sex with men (MSM) are at disproportionately high risk for HIV infection and an important population for trial recruitment. Investigations of willingness to participate (WTP) in HIV vaccine trials have focused predominantly on individual-level determinants. We explored multi-level factors associated with WTP among MSM in India. Methods We conducted 12 focus groups (n = 68) with low socioeconomic MSM in Chennai and Mumbai, and 14 key informant interviews with MSM community leaders and service providers. Focus groups/interviews were recorded, transcribed and translated into English. Two bilingual investigators conducted thematic analysis using line-by-line coding and a constant comparative method, with member-checking by community representatives. Results Factors associated with WTP were evidenced across the social ecology of MSM–social-structural: poverty, HIV-, sexual- and gender non-conformity stigma, institutionalized discrimination and government sponsorship of trials; community-level: endorsement by MSM community leaders and organizations, and fear of within-group discrimination; interpersonal: anticipated family discord, partner rejection, having financially-dependent family members and disclosure of same-sex sexuality; and individual-level: HIV vaccine trial knowledge and misconceptions, safety concerns, altruism and preventive misconception. Conclusion Pervasive familial, community and social-structural factors characteristic of the Indian sociocultural context may complicate individual-focused approaches to WTP and thereby constrain the effectiveness of interventions to support recruitment and retention in HIV vaccine trials. Interventions to reduce stigma and discrimination against MSM and people living with HIV, capacity-building of MSM community organizations and
Khan, Mohammad Imran; Sahito, Shah Muhammad; Khan, Mohammad Javed; Wassan, Shafi Mohammad; Shaikh, Abdul Wahab; Maheshwari, Ashok Kumar; Acosta, Camilo J.; Galindo, Claudia M.; Ochiai, Rion Leon; Rasool, Shahid; Peerwani, Sheeraz; Puri, Mahesh K.; Ali, Mohammad; Zafar, Afia; Hassan, Rumina; von Seidlein, Lorenz; Clemens, John D.; Nizami, Shaikh Qamaruddin; Bhutta, Zulfiqar A.
INTRODUCTION: In research projects such as vaccine trials, accurate and complete surveillance of all outcomes of interest is critical. In less developed countries where the private sector is the major health-care provider, the private sector must be included in surveillance systems in order to capture all disease of interest. This, however, poses enormous challenges in practice. The process and outcome of recruiting private practice clinics for surveillance in a vaccine trial are described. METHODS: The project started in January 2002 in two urban squatter settlements of Karachi, Pakistan. At the suggestion of private practitioners, a phlebotomy team was formed to provide support for disease surveillance. Children who had a reported history of fever for more than three days were enrolled for a diagnosis. RESULTS: Between May 2003 and April 2004, 5540 children younger than 16 years with fever for three days or more were enrolled in the study. Of the children, 1312 (24%) were seen first by private practitioners; the remainder presented directly to study centres. In total, 5329 blood samples were obtained for microbiology. The annual incidence of Salmonella typhi diagnosed by blood culture was 407 (95% confidence interval (95% CI), 368-448) per 100 000/year and for Salmonella paratyphi A was 198 (95% CI, 171-227) per 100 000/year. Without the contribution of private practitioners, the rates would have been 240 per 100 000/year (95% CI, 211-271) for S. typhi and 114 (95% CI, 94-136) per 100 000/year for S. paratyphi A. CONCLUSION: The private sector plays a major health-care role in Pakistan. Our experience from a surveillance and burden estimation study in Pakistan indicates that this objective is possible to achieve but requires considerable effort and confidence building. Nonetheless, it is essential to include private health care providers when attempting to accurately estimate the burden of disease in such settings. PMID:16501718
Background Shared decision making contributes to high quality healthcare by promoting a patient-centered approach. Patient involvement in selecting the components of a diabetes medication program that best match the patient’s values and preferences may also enhance medication adherence and improve outcomes. Decision aids are tools designed to involve patients in shared decision making, but their adoption in practice has been limited. In this study, we propose to obtain a preliminary estimate of the impact of patient decision aids vs. usual care on measures of patient involvement in decision making, diabetes care processes, medication adherence, glycemic and cardiovascular risk factor control, and resource utilization. In addition, we propose to identify, describe, and explain factors that promote or inhibit the routine embedding of decision aids in practice. Methods/Design We will be conducting a mixed-methods study comprised of a cluster-randomized, practical, multicentered trial enrolling clinicians and their patients (n = 240) with type 2 diabetes from rural and suburban primary care practices (n = 8), with an embedded qualitative study to examine factors that influence the incorporation of decision aids into routine practice. The intervention will consist of the use of a decision aid (Statin Choice and Aspirin Choice, or Diabetes Medication Choice) during the clinical encounter. The qualitative study will include analysis of video recordings of clinical encounters and in-depth, semi-structured interviews with participating patients, clinicians, and clinic support staff, in both trial arms. Discussion Upon completion of this trial, we will have new knowledge about the effectiveness of diabetes decision aids in these practices. We will also better understand the factors that promote or inhibit the successful implementation and normalization of medication choice decision aids in the care of chronic patients in primary care practices. Trial registration
Patzer, Rachel E.; Basu, Mohua; Mohan, Sumit; Smith, Kayla D.; Wolf, Michael; Ladner, Daniela; Friedewald, John J.; Chiles, Mariana; Russell, Allison; McPherson, Laura; Gander, Jennifer; Pastan, Stephen
Kidney transplantation is the preferred treatment for patients with end-stage renal disease, as it substantially increases a patient's survival and is cost saving compared to a lifetime of dialysis. However, transplantation is not universally chosen by patients with renal failure, and limited knowledge about the survival benefit of transplantation vs. dialysis may play a role. We created a mobile application clinical decision aid called iChoose Kidney to improve access to individualized prognosis information comparing dialysis and transplantation outcomes. We describe the iChoose Kidney study, a randomized controlled trial designed to test the clinical efficacy of a mobile health decision aid among end-stage renal disease patients referred for kidney transplantation at three large, diverse transplant centers across the U.S. Approximately 450 patients will be randomized to receive either: (1) standard of care or “usual” transplantation education, or (2) standard of care plus iChoose Kidney. The primary outcome is change in knowledge about the survival benefit of kidney transplantation vs. dialysis from baseline to immediate follow-up; secondary outcomes include change in treatment preferences, improved decisional conflict, and increased access to kidney transplantation. Analyses are also planned to examine effectiveness across subgroups of race, socioeconomic status, health literacy and health numeracy. Engaging patients in health care choices can increase patient empowerment and improve knowledge and understanding of treatment choices. If the effectiveness of iChoose Kidney has a greater impact on patients with low health literacy, lower socioeconomic status, and minority race, this decision aid could help reduce disparities in access to kidney transplantation. PMID:27610423
bioterrorism pathogens that threaten troops. 1. INTRODUCTION Hantaviruses are RNA viruses belonging to the family Bunyaviridae, and are...the etiologic agents of hemorrhagic fever with renal syndrome (HFRS) in the Old World and hantavirus pulmonary syndrome in the New World. The...viruses are carried by persistently infected rodents and are found worldwide. There are no licensed vaccines for hantaviruses ; thus, they continue to
Minhinnick, Alice; Satti, Iman; Harris, Stephanie; Wilkie, Morven; Sheehan, Sharon; Stockdale, Lisa; Thomas, Zita-Rose Manjaly; Lopez-Ramon, Raquel; Poulton, Ian; Lawrie, Alison; Vermaak, Samantha; Le Vert, Alexandre; Del Campo, Judith; Hill, Fergal; Moss, Paul; McShane, Helen
Introduction There is an urgent need for a new and effective tuberculosis vaccine because BCG does not sufficiently prevent pulmonary disease. IMX313 is a novel carrier protein designed to improve cellular and humoral immunity. MVA85A-IMX313 is a novel vaccine candidate designed to boost immunity primed by bacillus Calmette-Guérin (BCG) that has been immunogenic in pre-clinical studies. This is the first evaluation of IMX313 delivered as MVA85A-IMX313 in humans. Methods In this phase 1, open-label first-in-human trial, 30 healthy previously BCG-vaccinated adults were enrolled into three treatment groups and vaccinated with low dose MVA85A-IMX313 (group A), standard dose MVA85A-IMX313 (group B), or MVA85A (group C). Volunteers were followed up for 6 months for safety and immunogenicity assessment. Results The majority of adverse events were mild and there were no vaccine-related serious AEs. Both MVA85A-IMX313 and MVA85A induced a significant increase in IFN-γ ELISpot responses. There were no significant differences between the Ag85A ELISpot and intracellular cytokine responses between the two study groups B (MVA85A-IMX313) and C (MVA85A) at any time point post-vaccination. Conclusion MVA85A-IMX313 was well tolerated and immunogenic. There was no significant difference in the number of vaccine-related, local or systemic adverse reactions between MVA85A and MVA85A-IMX313 groups. The mycobacteria-specific cellular immune responses induced by MVA85A-IMX313 were not significantly different to those detected in the MVA85A group. In light of this encouraging safety data, further work to improve the potency of molecular adjuvants like IMX313 is merited. This trial was registered on clinicatrials.gov ref. NCT01879163. PMID:26854906
Stelzer, K.J.; Griffin, T.W. )
The optimal dose of radiation in the treatment of AIDS-associated Kaposi's sarcoma has been controversial based on previous nonrandomized retrospective studies. Seventy-one cutaneous AIDS-associated Kaposi's sarcoma lesions were randomly assigned to 1 of 3 radiation dose regimens--8 Gy in 1 fraction, 20 Gy in 10 fractions, and 40 Gy in 20 fractions. Lesions were measured prior to and following treatment. Complete resolution of palpable tumor was considered a complete response, regardless of residual purple pigmentation. Reduction in palpable tumor to less than 50% of pretreatment area was considered an objective response. Less than 50% reduction in tumor size was considered a nonresponse. Complete response was higher (p = .04) with 40 Gy (83%) and 20 Gy (79%) than with 8 Gy (50%). Absence of residual purple pigmentation was greater (p = .005) with 40 Gy (43%) than with 20 Gy (8%) or 8 Gy (8%). Lesion failure was lower (p = .03) with 40 Gy (52%) than with 20 Gy (67%) or 8 Gy (88%). Median time to failure was 43 weeks with 40 Gy, 26 weeks with 20 Gy, and 13 weeks with 8 Gy (p = .003). Fractionated radiotherapy to higher total doses resulted in improved response and control of cutaneous Kaposi's sarcoma. This dose-dependence should be considered in determining the optimal radiotherapeutic regimen for individual patients treated for epidemic Kaposi's sarcoma. 11 refs., 1 fig., 4 tabs.
vaccine, it could be used to increase the public health impact of rotavirus immunization. Trial registration Clinical Trial Registry, India (CTRI/2012/10/003057), Clinicaltrials.gov (NCT01700127). Date of Registration: Clinical Trial Registry, India: 28 September 2012, Clinicaltrials.gov: 3 October 2012. PMID:24976452
Talaat, Kawsar R.; Karron, Ruth A.; Liang, Philana H.; McMahon, Bridget A.; Luke, Catherine J.; Thumar, Bhagvanji; Chen, Grace L.; Min, Ji‐Young; Lamirande, Elaine W.; Jin, Hong; Coelingh, Kathy L.; Kemble, George W.; Subbarao, Kanta
Please cite this paper as: Talaat et al. (2012) An open‐label phase I trial of a live attenuated H2N2 influenza virus vaccine in healthy adults. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00350.x. Background Live attenuated influenza vaccines (LAIV) against a variety of strains of pandemic potential are being developed and tested. We describe the results of an open‐label phase I trial of a live attenuated H2N2 virus vaccine. Objectives To evaluate the safety, infectivity, and immunogenicity of a live attenuated H2N2 influenza virus vaccine. Participants/methods The A/Ann Arbor/6/60 (H2N2) virus used in this study is the attenuated, cold‐adapted, temperature‐sensitive strain that provides the genetic backbone of seasonal LAIV (MedImmune). We evaluated the safety, infectivity, and immunogenicity of two doses of 107 TCID50 of this vaccine administered by nasal spray 4 weeks apart to normal healthy seronegative adults. Results Twenty‐one participants received a first dose of the vaccine; 18 participants received a second dose. No serious adverse events occurred during the trial. The most common adverse events after vaccination were headache and musculoskeletal pain. The vaccine was restricted in replication: 24% and 17% had virus detectable by culture or rRT‐PCR after the first and second dose, respectively. Antibody responses to the vaccine were also restricted: 24% of participants developed an antibody response as measured by either hemagglutination‐inhibition assay (10%), or ELISA for H2 HA‐specific serum IgG (24%) or IgA (16%) after either one or two doses. None of the participants had a neutralizing antibody response. Vaccine‐specific IgG‐secreting cells as measured by enzyme‐linked immunospot increased from a mean of 0·5 to 2·0/106 peripheral blood mononuclear cells (PBMCs); vaccine‐specific IgA‐secreting cells increased from 0·1 to 0·5/106 PBMCs. Conclusions The live attenuated H2N2
Durez, Patrick; Vandepapeliere, Pierre; Miranda, Pedro; Toncheva, Antoaneta; Berman, Alberto; Kehler, Tatjana; Mociran, Eugenia; Fautrel, Bruno; Mariette, Xavier; Dhellin, Olivier; Fanget, Bernard; Ouary, Stephane; Grouard-Vogel, Géraldine; Boissier, Marie-Christophe
Objectives Active immunization, or vaccination, with tumor necrosis factor (TNF)-Kinoid (TNF-K) is a novel approach to induce polyclonal anti-TNF antibodies in immune-mediated inflammatory diseases. This study was performed to transfer the proof of concept obtained in mice model of rheumatoid arthritis (RA) into human. We designed a pilot study to demonstrate the feasibility of therapeutic vaccination in RA. Methods This was a phase IIa, placebo-controlled, multicenter study in adults with RA who previously experienced secondary failure of TNF antagonists. Patients were immunized intramuscularly with 2 or 3 doses of placebo (n = 10) or 90 (n = 6), 180 (n = 12), or 360 µg TNF-K (n = 12). The primary objective was to identify the best dose and schedule based on anti-TNF antibody titers. Clinical symptoms and safety were assessed during 12 months and solicited reactions for 7 days after each injection. Results The highest anti-TNF antibody response was detected in patients immunized with 360 µg TNF-K and with 3 injections, although this difference was not significant with all other groups. Similar proportions of patients receiving TNF-K and placebo reported adverse events up to month 12. Serious adverse events were reported by 4 patients treated with TNF-K (13.3%) and 3 treated with placebo (30.0%), all unrelated to treatment. At month 12, DAS28-CRP, tender and swollen joint counts, and HAQ scores decreased significantly more in patients who exhibited anti-TNF antibody response than in patients who did not. Conclusions TNF-K therapeutic vaccination induced dose- and schedule-dependent anti-TNF antibodies in RA patients and was well tolerated. Patients who developed anti-TNF antibodies showed a trend toward clinical improvement. Although the most aggressive dose and schedule, i.e. 360 mg dose administered 3 times, did show a strong trend of higher antibody response, further studies are warranted to examine even higher and more frequent doses in order
Randomized trial of the immunogenicity and safety of the Hepatitis B vaccine given in an accelerated schedule coadministered with the human papillomavirus type 16/18 AS04-adjuvanted cervical cancer vaccine.
Leroux-Roels, Geert; Haelterman, Edwige; Maes, Cathy; Levy, Jack; De Boever, Fien; Licini, Laurent; David, Marie-Pierre; Dobbelaere, Kurt; Descamps, Dominique
The human papillomavirus type 16/18 (HPV-16/18) AS04-adjuvanted cervical cancer vaccine is licensed for females aged 10 years and above and is therefore likely to be coadministered with other licensed vaccines, such as hepatitis B. In this randomized, open-label study, we compared the immunogenicity of the hepatitis B vaccine administered alone (HepB group) or with the HPV-16/18 AS04-adjuvanted vaccine (HepB+HPV group) in healthy women aged 20 to 25 years (clinical trial NCT00637195). The hepatitis B vaccine was given at 0, 1, 2, and 12 months (an accelerated schedule which may be required by women at high risk), and the HPV-16/18 vaccine was given at 0, 1, and 6 months. One month after the third dose of hepatitis B vaccine, in the according-to-protocol cohort (n = 72 HepB+HPV; n = 76 HepB), hepatitis B seroprotection rates (titer of ≥10 mIU/ml) were 96.4% (95% confidence interval [CI], 87.5 to 99.6) and 96.9% (CI, 89.2 to 99.6) in the HepB+HPV and HepB groups, respectively, in women initially seronegative for anti-hepatitis B surface antigen (HBs) and anti-hepatitis B core antigen (HBc). Corresponding geometric mean titers of anti-HBs antibodies were 60.2 mIU/ml (CI, 40.0 to 90.5) and 71.3 mIU/ml (CI, 53.9 to 94.3). Anti-HBs antibody titers rose substantially after the fourth dose of hepatitis B vaccine. All women initially seronegative for anti-HPV-16 and anti-HPV-18 antibodies seroconverted after the second HPV-16/18 vaccine dose and remained seropositive up to 1 month after the third dose. Both vaccines were generally well tolerated, with no difference in reactogenicity between groups. In conclusion, coadministration of the HPV-16/18 AS04-adjuvanted vaccine did not affect the immunogenicity or safety of the hepatitis B vaccine administered in an accelerated schedule in young women.
Verma, Anurag; Bradford, Yuki; Verma, Shefali S.; Pendergrass, Sarah A.; Daar, Eric S.; Venuto, Charles; Morse, Gene D.; Ritchie, Marylyn D.
Background High-throughput approaches are increasingly being used to identify genetic associations across multiple phenotypes simultaneously. Here, we describe a pilot analysis that considered multiple on-treatment laboratory phenotypes from antiretroviral therapy-naive patients who were randomized to initiate antiretroviral regimens in a prospective clinical trial, AIDS Clinical Trials Group protocol A5202. Participants and methods From among 5 9545 294 polymorphisms imputed genome-wide, we analyzed 2544, including 2124 annotated in the PharmGKB, and 420 previously associated with traits in the GWAS Catalog. We derived 774 phenotypes on the basis of context from six variables: plasma atazanavir (ATV) pharmacokinetics, plasma efavirenz (EFV) pharmacokinetics, change in the CD4+ T-cell count, HIV-1 RNA suppression, fasting low-density lipoprotein-cholesterol, and fasting triglycerides. Permutation testing assessed the likelihood of associations being by chance alone. Pleiotropy was assessed for polymorphisms with the lowest P-values. Results This analysis included 1181 patients. At P less than 1.5×10−4, most associations were not by chance alone. Polymorphisms with the lowest P-values for EFV pharmacokinetics (CYPB26 rs3745274), low-density lipoprotein -cholesterol (APOE rs7412), and triglyceride (APOA5 rs651821) phenotypes had been associated previously with those traits in previous studies. The association between triglycerides and rs651821 was present with ATV-containing regimens, but not with EFV-containing regimens. Polymorphisms with the lowest P-values for ATV pharmacokinetics, CD4 T-cell count, and HIV-1 RNA phenotypes had not been reported previously to be associated with that trait. Conclusion Using data from a prospective HIV clinical trial, we identified expected genetic associations, potentially novel associations, and at least one context-dependent association. This study supports high-throughput strategies that simultaneously explore multiple
Hansen, Nathan B.; Tarakeshwar, Nalini; Ghebremichael, Musie; Zhang, Heping; Kochman, Arlene; Sikkema, Kathleen J.
This study examined the longitudinal effects of coping on outcome one year following completion of a randomized, controlled trial of a group coping intervention for AIDS-related bereavement. Bereaved HIV-positive participants (N = 267) were administered measures of grief, psychiatric distress, quality of life, and coping at baseline,…
Background A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission. Methods and Findings 6,537 infants aged 6–12 wk and 8,923 children aged 5–17 mo were randomized to receive three doses of RTS,S/AS01 or comparator vaccine. VE against clinical malaria in children during the 18 mo after vaccine dose 3 (per protocol) was 46% (95% CI 42% to 50%) (range 40% to 77%; VE, p<0.01 across all sites). VE during the 20 mo after vaccine dose 1 (intention to treat [ITT]) was 45% (95% CI 41% to 49%). VE against severe malaria, malaria hospitalization, and all-cause hospitalization was 34% (95% CI 15% to 48%), 41% (95% CI 30% to 50%), and 19% (95% CI 11% to 27%), respectively (ITT). VE against clinical malaria in infants was 27% (95% CI 20% to 32%, per protocol; 27% [95% CI 21% to 33%], ITT), with no significant protection against severe malaria, malaria hospitalization, or all-cause hospitalization. Post-vaccination anti-circumsporozoite antibody geometric mean titer varied from 348 to 787 EU/ml across sites in children and from 117 to 335 EU/ml in infants (per protocol). VE waned over time in both age categories (Schoenfeld residuals p<0.001). The number of clinical and severe malaria cases averted per 1,000 children vaccinated ranged across sites from 37 to 2,365 and from −1 to 49, respectively; corresponding ranges among infants were −10 to 1,402 and −13 to 37, respectively (ITT). Meningitis was reported as a serious adverse event in 16/5,949 and 1/2,974 children and in 9/4,358 and 3/2,179 infants in the RTS,S/AS01 and control groups, respectively. Conclusions RTS,S/AS01 prevented many cases of clinical and severe malaria over the 18 mo after vaccine dose 3, with the highest impact in areas with the greatest malaria incidence. VE was higher in children than in infants, but even at
Brady, Rebecca C; Hu, Wilson; Houchin, Vonda G; Eder, Frank S; Jackson, Kenneth C; Hartel, Gunter F; Sawlwin, Daphne C; Albano, Frank R; Greenberg, Michael
A trivalent inactivated influenza vaccine (CSL's TIV, CSL Limited) was licensed under USA accelerated approval regulations for use in persons≥18 years. We performed a randomized, observer-blind study to assess the safety and immunogenicity of CSL's TIV versus an established US-licensed vaccine in a population≥6 months to <18 years of age. Subjects were stratified as follows: Cohort A (≥6 months to <3 years); Cohort B (≥3 years to <9 years); and Cohort C (≥9 years to <18 years). The subject's age and influenza vaccination history determined the dosing regimen (one or two vaccinations). Subjects received CSL's TIV (n=739) or the established vaccine (n=735) in the autumn of 2009. Serum hemagglutination-inhibition titers were determined pre-vaccination and 30 days after the last vaccination. No febrile seizures or other vaccine-related SAEs were reported. After the first vaccination for Cohorts A and B, respectively, the relative risks of fever were 2.73 and 2.32 times higher for CSL's TIV compared to the established vaccine. Irritability and loss of appetite (for Cohort A) and malaise (for Cohort B) were also significantly higher for CSL's TIV compared to the established vaccine. Post-vaccination geometric mean titers (GMTs) for CSL's TIV versus the established vaccine were 385.49 vs. 382.45 for H1N1; 669.13 vs. 705.61 for H3N2; and 100.65 vs. 93.72 for B. CSL's TIV demonstrated immunological non-inferiority to the established vaccine in all cohorts.
Moorthy, V S; Diggs, C; Ferro, S; Good, M F; Herrera, S; Hill, A V; Imoukhuede, E B; Kumar, S; Loucq, C; Marsh, K; Ockenhouse, C F; Richie, T L; Sauerwein, R W
Development and optimization of first generation malaria vaccine candidates has been facilitated by the existence of a well-established Plasmodium falciparum clinical challenge model in which infectious sporozoites are administered to human subjects via mosquito bite. While ideal for testing pre-erythrocytic stage vaccines, some researchers believe that the sporozoite challenge model is less appropriate for testing blood stage vaccines. Here we report a consultation, co-sponsored by PATH MVI, USAID, EMVI and WHO, where scientists from all institutions globally that have conducted such clinical challenges in recent years and representatives from regulatory agencies and funding agencies met to discuss clinical malaria challenge models. Participants discussed strengthening and harmonizing the sporozoite challenge model and considered the pros and cons of further developing a blood stage challenge possibly better suited for evaluating the efficacy of blood stage vaccines. This report summarizes major findings and recommendations, including an update on the Plasmodium vivax clinical challenge model, the prospects for performing experimental challenge trials in malaria endemic countries and an update on clinical safety data. While the focus of the meeting was on the optimization of clinical challenge models for evaluation of blood stage candidate malaria vaccines, many of the considerations are relevant for the application of challenge trials to other purposes.
Bauer, Kristen; Esquilin, Ines O.; Cornier, Alberto Santiago; Thomas, Stephen J.; Quintero del Rio, Ana I.; Bertran-Pasarell, Jorge; Morales Ramirez, Javier O.; Diaz, Clemente; Carlo, Simon; Eckels, Kenneth H.; Tournay, Elodie; Toussaint, Jean-Francois; De La Barrera, Rafael; Fernandez, Stefan; Lyons, Arthur; Sun, Wellington; Innis, Bruce L.
This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1–50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2–4 years], 60% [5–20 years], and 93% [21–50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858. PMID:26175027
Bauer, Kristen; Esquilin, Ines O; Cornier, Alberto Santiago; Thomas, Stephen J; Quintero Del Rio, Ana I; Bertran-Pasarell, Jorge; Morales Ramirez, Javier O; Diaz, Clemente; Carlo, Simon; Eckels, Kenneth H; Tournay, Elodie; Toussaint, Jean-Francois; De La Barrera, Rafael; Fernandez, Stefan; Lyons, Arthur; Sun, Wellington; Innis, Bruce L
This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1-50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2-4 years], 60% [5-20 years], and 93% [21-50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858.
Tovanabutra, Sodsai; Rerks-Ngarm, Supachai; Nitayaphan, Sorachai; Eamsila, Chirapa; Kunasol, Prayura; Khamboonruang, Chirasak; Thongcharoen, Prasert; Namwat, Chawetsan; Premsri, Nakorn; Benenson, Michael; Morgan, Patricia; Bose, Meera; Sanders-Buell, Eric; Paris, Robert; Robb, Merlin L.; Birx, Deborah L.; De Souza, Mark S.; McCutchan, Francine E.; Michael, Nelson L.; Kim, Jerome H.
The RV144 HIV-1 vaccine trial (Thailand, 2003 to 2009), using immunogens genetically matched to the regional epidemic, demonstrated the first evidence of efficacy for an HIV-1 vaccine. Here we studied the molecular evolution of the HIV-1 epidemic from the time of immunogen selection to the execution of the efficacy trial. We studied HIV-1 genetic diversity among 390 volunteers who were deferred from enrollment in RV144 due to preexisting HIV-1 infection using a multiregion hybridization assay, full-genome sequencing, and phylogenetic analyses. The subtype distribution was 91.7% CRF01_AE, 3.5% subtype B, 4.3% B/CRF01_AE recombinants, and 0.5% dual infections. CRF01_AE strains were 31% more diverse than the ones from the 1990s Thai epidemic. Sixty-nine percent of subtype B strains clustered with the cosmopolitan Western B strains. Ninety-three percent of B/CRF01_AE recombinants were unique; recombination breakpoint analysis showed that these strains were highly embedded within the larger network that integrates recombinants from East/Southeast Asia. Compared to Thai sequences from the early 1990s, the distance to the RV144 immunogens increased 52% to 68% for CRF01_AE Env immunogens and 12% to 29% for subtype B immunogens. Forty-three percent to 48% of CRF01_AE sequences differed from the sequence of the vaccine insert in Env variable region 2 positions 169 and 181, which were implicated in vaccine sieve effects in RV144. In conclusion, compared to the molecular picture at the early stages of vaccine development, our results show an overall increase in the genetic complexity of viruses in the Thai epidemic and in the distance to vaccine immunogens, which should be considered at the time of the analysis of the trial results. PMID:23576510
Antonilli, Morena; Rahimi, Hassan; Visconti, Valeria; Napoletano, Chiara; Ruscito, Ilary; Zizzari, Ilaria Grazia; Caponnetto, Salvatore; Barchiesi, Giacomo; Iadarola, Roberta; Pierelli, Luca; Rughetti, Aurelia; Bellati, Filippo; Panici, Pierluigi Benedetti; Nuti, Marianna
Vaccination with priming and expansion of tumour reacting T cells is an important therapeutic option to be used in combination with novel checkpoint inhibitors to increase the specificity of the T cell infiltrate and the efficacy of the treatment. In this phase I/II study, 14 high-risk disease-free ovarian (OC) and breast cancer (BC) patients after completion of standard therapies were vaccinated with MUC1, ErbB2 and carcinoembryonic antigen (CEA) HLA-A2+-restricted peptides and Montanide. Patients were subjected to 6 doses of vaccine every two weeks and a recall dose after 3 months. ECOG grade 2 toxicity was observed at the injection site. Eight out of 14 patients showed specific CD8+ T cells to at least one antigen. None of 4 patients vaccinated for compassionate use showed a CD8 activation. An OC patient who suffered from a lymph nodal recurrence, showed specific anti-ErbB2 CD8+ T cells in the bulky aortic lymph nodes suggesting homing of the activated T cells. Results confirm that peptide vaccination strategy is feasible, safe and well tolerated. In particular OC patients appear to show a higher response rate compared to BC patients. Vaccination generates a long-lasting immune response, which is strongly enhanced by recall administrations. The clinical outcome of patients enrolled in the trial appears favourable, having registered no deceased patients with a minimum follow-up of 8 years. These promising data, in line with the results of similar studies, the high compliance of patients observed and the favourable toxicity profile, support future trials of peptide vaccination in clinically disease-free patients who have completed standard treatments.
Screening for the community-based, phase III, prime-boost HIV vaccine trial conducted in Thailand (also referred to as "RV144") began in September 2003 and concluded in December 2005 in Rayong and Chon Buri provinces. During this period 26,676 persons were consented and screened for vaccine trial eligibility in a separate protocol ("RV148") at 47 screening sites, of which 26,548 were tested for HIV, and 16,402 were ultimately enrolled in RV144 and received at least one vaccination or corresponding placebo injection. Fifty-eight percent of those enrolled in RV148 were men and roughly half of the men and women were married. A slight majority was born in the provinces in which the study was conducted. The median age was 23 (IQR 20-26) and most had achieved a level of education that was higher than grade 9, which is compulsory for Thai citizens. The prevalence of confirmed HIV infection was 1.6%; among persons who did not return for confirmatory testing, it was 2.0%. Eighty-three percent were infected with CRF01_AE strains (formerly subtype E) as determined by serological typing. The estimated incidence of HIV infection using a capture EIA assay was 0.19 per 100 person-years. Female sex, older age, single marital status, and lower educational attainment were associated with HIV infection. Persons who reported working in the fishing or sex-work industries were more frequently infected (2.4% and 4.1%, respectively), but accounted for a small percent of the tested population in RV148 (0.7% and 0.6%, respectively), reflecting the overall low-risk of HIV in this study. Those screened for eligibility but did not participate in the vaccine trial were not substantially different from enrolled vaccine trial subjects.
Pittman, Phillip R; Reisler, Ronald B; Lindsey, Changhong Y; Güereña, Fernando; Rivard, Robert; Clizbe, Denise P; Chambers, Matthew; Norris, Sarah; Smith, Leonard A
Ricin is a potent toxin and potential bioterrorism weapon for which no specific licensed countermeasures are available. We report the safety and immunogenicity of the ricin vaccine RVEc™ in a Phase 1 (N=30) multiple-dose, open-label, non-placebo-controlled, dose-escalating (20, 50, and 100μg), single-center study. Each subject in the 20- and 50-μg dose groups (n=10 for each group) received three injections at 4-week intervals and was observed carefully for untoward effects of the vaccine; blood was drawn at predetermined intervals after each dose for up to 1 year. RVEc™ was safe and well tolerated at the 20- and 50-μg doses. The most common adverse events were pain at the injection site and headache. Of the 10 subjects who received a single 100-μg dose, two developed elevated creatine phosphokinase levels, which resolved without sequelae. No additional doses were administered to subjects in the 100-μg group. Immunogenicity of the vaccine was evaluated by measuring antibody response using the well standardized enzyme-linked immunosorbent assay (ELISA) and toxin neutralization assay (TNA). Of the subjects in the 20- and 50-μg dose groups, 100% achieved ELISA anti-ricin IgG titers of 1:500 to 1:121,500 and 50% produced neutralizing anti-ricin antibodies measurable by TNA. Four subjects in the 50-μg group received a single booster dose of RVEc™ 20-21 months after the initial dose. The single booster was safe and well tolerated, resulting in no serious adverse events, and significantly enhanced immunogenicity of the vaccine in human subjects. Each booster recipient developed a robust anamnestic response with ELISA anti-ricin IgG titers of 1:13,500 to 1:121,500 and neutralizing antibody titers of 1:400 to 1:3200. Future studies will attempt to optimize dose, scheduling, and route of administration. This study is registered at clinicaltrials.gov (NCT01317667 and NCT01846104).
Ardavanis, Alexandros; Litton, Jennifer K.; Shumway, Nathan M.; Hale, Diane F.; Murray, James L.; Perez, Sonia A.; Ponniah, Sathibalan; Baxevanis, Constantin N.; Papamichail, Michael
GP2 is a HER2-derived, HLA-A2+ restricted peptide. Phase I studies showed GP2 administered with GM-CSF to be safe and immunogenic. Here we report the primary analysis of a prospective, randomized, multicenter phase II adjuvant trial conducted to determine the vaccine's efficacy. The trial enrolled HLA-A2+, clinically disease-free, node-positive and high-risk node-negative breast cancer patients with tumors expressing HER2 (immunohistochemistry[IHC] 1+-3+). Patients were randomized to GP2+GM-CSF versus GM-CSF alone. Disease-free survival (DFS) was analyzed in intention-to-treat (ITT) and per-treatment cohorts; pre-specified subgroup analyses were performed for patients with IHC 3+ or FISH+ disease. The trial enrolled 180 patients; 89 received GP2+GM-CSF and 91 received GM-CSF alone. The groups were well-matched for clinicopathologic characteristics. Toxicities have been minimal. The Kaplan-Meier estimated 5-year DFS rate in the ITT analyses was 88% (95% CI:78-94%) in vaccinated vs. 81% (95% CI:69-89%) (P = 0.43) in control patients after a 34 month median follow-up. In the per-treatment analysis, the estimated 5-year DFS rates were 94% (95% CI:83-98%) and 85% (73-92%) (P = 0.17). In IHC 3+/FISH+ patients, the estimated 5-year DFS rate was 94% (82-98%) in vaccinated patients (n = 51) vs. 89% (71-96%) in control patients (n = 50), (P = 0.86) in the ITT analyses and 100% vs. 89% (71-96%) in vaccinated vs. control patients in the per-treatment analyses (P = 0.08). While the overall ITT analysis did not demonstrate benefit to vaccination, this trial confirmed that the GP2 vaccine is safe and suggests that vaccination may have clinical activity, particularly in patients with HER2 overexpression who received the full vaccine series (ie per-treatment group). PMID:27589688
Bennett, John V.; Fernandez de Castro, Jorge; Valdespino-Gomez, Jose Luis; Garcia-Garcia, Ma de Lourdes; Islas-Romero, Rocio; Echaniz-Aviles, Gabriela; Jimenez-Corona, Aida; Sepulveda-Amor, Jaime
OBJECTIVE: To compare antibody responses and side-effects of aerosolized and injected measles vaccines after revaccination of children enrolling in elementary schools. METHODS: Vaccines for measles (Edmonston-Zagreb) or measles-rubella (Edmonston-Zagreb with RA27/3) were given by aerosol or injection to four groups of children. An additional group received Schwarz measles vaccine by injection. These five groups received vaccines in usual standard titre doses. A sixth group received only 1000 plaque-forming units of Edmonston-Zagreb vaccine by aerosol. The groups were randomized by school. Concentrations of neutralizing antibodies were determined in blood specimens taken at baseline and four months after vaccination from randomized subgroups (n = 28-31) of children in each group. FINDINGS: After baseline antibody titres were controlled for, the frequencies of fourfold or greater increases in neutralizing antibodies did not differ significantly between the three groups that received vaccine by aerosol (range 52%-64%), but they were significantly higher than those for the three groups that received injected vaccine (range 4%-23%). Mean increases in titres and post-vaccination geometric mean titres paralleled these findings. Fewer side-effects were noted after aerosol than injection administration of vaccine. CONCLUSION: Immunogenicity of measles vaccine when administered by aerosol is superior to that when the vaccine is given by injection. This advantage persists with aerosolized doses less than or equal to one-fifth of usual injected doses. The efficacy and cost-effectiveness of measles vaccination by aerosol should be further evaluated in mass campaigns. PMID:12471401
Hodgson, Susanne H; Choudhary, Prateek; Elias, Sean C; Milne, Kathryn H; Rampling, Thomas W; Biswas, Sumi; Poulton, Ian D; Miura, Kazutoyo; Douglas, Alexander D; Alanine, Daniel Gw; Illingworth, Joseph J; de Cassan, Simone C; Zhu, Daming; Nicosia, Alfredo; Long, Carole A; Moyle, Sarah; Berrie, Eleanor; Lawrie, Alison M; Wu, Yimin; Ellis, Ruth D; Hill, Adrian V S; Draper, Simon J
The development of effective vaccines against difficult disease targets will require the identification of new subunit vaccination strategies that can induce and maintain effective immune responses in humans. Here we report on a phase 1a clinical trial using the AMA1 antigen from the blood-stage Plasmodium falciparum malaria parasite delivered either as recombinant protein formulated with Alhydrogel adjuvant with and without CPG 7909, or using recombinant vectored vaccines--chimpanzee adenovirus ChAd63 and the orthopoxvirus MVA. A variety of promising "mixed-modality" regimens were tested. All volunteers were primed with ChAd63, and then subsequently boosted with MVA and/or protein-in-adjuvant using either an 8- or 16-week prime-boost interval. We report on the safety of these regimens, as well as the T cell, B cell, and serum antibody responses. Notably, IgG antibody responses primed by ChAd63 were comparably boosted by AMA1 protein vaccine, irrespective of whether CPG 7909 was included in the Alhydrogel adjuvant. The ability to improve the potency of a relatively weak aluminium-based adjuvant in humans, by previously priming with an adenoviral vaccine vector encoding the same antigen, thus offers a novel vaccination strategy for difficult or neglected disease targets when access to more potent adjuvants is not possible.
Creech, C Buddy; Dekker, Cornelia L; Ho, Dora; Phillips, Shanda; Mackey, Sally; Murray-Krezan, Cristina; Grazia Pau, Maria; Hendriks, Jenny; Brown, Valerie; Dally, Leonard G; Versteege, Isabella; Edwards, Kathryn M
Malaria results in over 650 000 deaths each year; thus, there is an urgent need for an effective vaccine. Pre-clinical studies and recently reported human trials suggest that pre-erythrocytic stage vaccines can provide protection against infection. A Phase 1, randomized, placebo-controlled, dose-escalation study was conducted with a vaccine composed of a replication-deficient adenovirus-35 backbone with P. falciparum circumsporozoite (CS) surface antigen (Ad35.CS.01). Healthy adult subjects received three doses of 108, 109, 1010, or 1011 vp/mL Ad35.CS.01 vaccine or saline placebo intramuscularly at 0, 1, and 6-mo intervals. Adverse events were assessed and anti-CS antibody responses were determined by ELISA. Seventy-two individuals were enrolled, with age, gender, and ethnicity similar across each study arm. While the vaccine was generally well tolerated, adverse events were more frequent in the highest dose groups (1010 and 1011 vp/mL). More robust humoral responses were also noted at the highest doses, with 73% developing a positive ELISA response after the three dose series of 1011 vp/mL. The Ad35.CS.01 vaccine was most immunogenic at the highest dosages (1010 and 1011 vp/mL). Reactogenicity findings were more common after the 1011 vp/mL dose, although most were mild or moderate in nature and resolved without therapy. PMID:23955431
Skinner, G R; Turyk, M E; Benson, C A; Wilbanks, G D; Heseltine, P; Galpin, J; Kaufman, R; Goldberg, L; Hartley, C E; Buchan, A
A randomised, placebo-controlled, multi-centre trial of intracellular subunit herpes simplex virus (HSV) type 1 vaccine NFU.Ac.HSV-1(S-)MRC (Skinner vaccine) was conducted at three medical centres in the United States. Subjects with documented herpes genitalis of at least 1-year duration and a history of six or more genital HSV recurrences in the 12 months prior to study entry were randomised to receive vaccine or placebo at 0, 1 and 2 months. Vaccination induced significant neutralising, enzyme-linked immunosorbent assay and lymphocyte transformation response to HSV-1 antigen. The frequency of recurrences was reduced in the vaccinated female patients at both 3 and 6 months following vaccination with an overall reduction in patients of both sexes which did not reach statistical significance. Recurrence severity was reduced as measured by decreased number of lesions and associated symptoms per recurrence (P = 0.04). The data suggest that clinical manifestations of latent HSV genital infection may be modified by therapeutic immunisation.
Valera, Rodrigo; García, Hilda María; Jidy, Manuel Díaz; Mirabal, Mayelin; Armesto, Marlene Isabel; Fando, Rafael; García, Luis; Fernández, Roberto; Año, Gemma; Cedré, Bárbara; Ramírez, Margarita; Bravo, Laura; Serrano, Teresita; Palma, Sara; González, Daniel; Miralles, Fernando; Medina, Vilma; Nuñez, Felicita; Plasencia, Yilian; Martínez, Juan Carlos; Mandarioti, Aleyda; Lugones, Juan; Rodríguez, Boris Luis; Moreno, Arlenis; González, Domingo; Baro, Morelia; Solis, Rosa Lidia; Sierra, Gustavo; Barbera, Ramón; Domínguez, Francisco; Gutiérrez, Carlos; Kouri, Gustavo; Campa, Concepción; Menéndez, Jorge
A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the safety, reactogenicity and the immunogenicity of a 2 x 10(9)CFU dose of the 638 lyophilized live attenuated cholera vaccine for oral administration, formulated and produced at Finlay Institute, City of Havana, Cuba. Thirty-six healthy female and male adult volunteers from 18 to 40 years old were involved, clinically examined and laboratory tested after the informed consent signature. Adverse events were monitored and seroconversion rates and geometrical mean titer (GMT) of vibriocidal antibodies were tested in volunteer's sera samples. Neither serious adverse events nor other damages to the volunteers due to vaccine or placebo feeding were reported during the clinical follow-up period of this study; none of the adverse events registered within the first 72 h after inoculation were life-threatening for volunteers. Neither severe nor moderate adverse events were reported. Sixty-one percent of subjects showed mild expected adverse events in an interval lower than 24h up to the first 72 h, 75% of these in the vaccinated group and 18% in the placebo group. Fourteen days after inoculation the GMT of vibriocidal antibodies in the vaccine group significantly increased in comparison to the placebo group. All subjects in the vaccine group (24) seroconverted (100%). Results show that this vaccine is safe, well tolerated and immunogenic in healthy female and male volunteers.
Solarte, Yezid; Manzano, María R.; Rocha, Leonardo; Hurtado, Hugo; James, Mark A.; Arévalo-Herrera, Myriam; Herrera, Sócrates
Vaccine development for Plasmodium vivax malaria is underway. A model to assess the protective efficacy of vaccine candidates in humans is urgently needed. Given the lack of continuous P. vivax cultures, we developed a system to infect Anopheles albimanus mosquitoes using blood from P. vivax-infected patients and determined parameters for challenge of malaria-naive volunteers by mosquito bite. Absence of co-infections in parasitized blood was confirmed by tests consistent with blood bank screening. A total of 119 experiments were conducted using batches of 900–4,500 mosquitoes fed by an artificial membrane feeding method. Optimal conditions for mosquito probing and infection were determined. Presence of oocyst and sporozoites were assessed on Days 7–8 and 14–15, respectively, and conditions to choose batches of infected mosquitoes for sporozoite challenge were established. Procedures to infect volunteers took a 2-hour period including verification of inoculum dose. Anopheles albimanus mosquitoes represent a valuable resource for P. vivax sporozoite challenge of volunteers. PMID:21292875
Munoz, Flor M; Weisman, Leonard E; Read, Jennifer S; Siberry, George; Kotloff, Karen; Friedman, Jennifer; Higgins, Rosemary D; Hill, Heather; Seifert, Harry; Nesin, Mirjana
A panel of experts convened by the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, developed proposed guidelines for the evaluation of adverse events in newborns of women participating in clinical trials of maternal immunization in the United States.
Munoz, Flor M.; Weisman, Leonard E.; Read, Jennifer S.; Siberry, George; Kotloff, Karen; Friedman, Jennifer; Higgins, Rosemary D.; Hill, Heather; Seifert, Harry; Nesin, Mirjana
A panel of experts convened by the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, developed proposed guidelines for the evaluation of adverse events in newborns of women participating in clinical trials of maternal immunization in the United States. PMID:25425720
Slingluff, Craig L.; Petroni, Gina R.; Chianese-Bullock, Kimberly A.; Smolkin, Mark E.; Ross, Merrick I.; Haas, Naomi B.; von Mehren, Margaret; Grosh, William W.
Purpose This multicenter randomized trial was designed to test whether melanoma-associated helper peptides augment CD8+ T-cell responses to a melanoma vaccine and whether cyclophosphamide (CY) pretreatment augments CD4+ or CD8+ T-cell responses to that vaccine. Patients and Methods In all, 167 eligible patients with resected stage IIB to IV melanoma were randomly assigned to four vaccination study arms. Patients were vaccinated with 12 class I major histocompatibility complex–restricted melanoma peptides (12MP) to stimulate CD8+ T cells and were randomly assigned to receive a tetanus helper peptide or a mixture of six melanoma-associated helper peptides (6MHP) to stimulate CD4+ T cells. Before vaccination, patients were also randomly assigned to receive CY pretreatment or not. T-cell responses were assessed by an ex vivo interferon gamma ELISpot assay. Clinical outcomes and toxicities were recorded. Results Vaccination with 12MP plus tetanus induced CD8+ T-cell responses in 78% of patients and CD4+ T-cell responses to tetanus peptide in 93% of patients. Vaccination with 12MP plus 6MHP induced CD8+ responses in 19% of patients and CD4+ responses to 6MHP in 48% of patients. CY had no significant effect on T-cell responses. Overall 3-year survival was 79% (95% CI, 71% to 86%), with no significant differences (at this point) by study arm. Conclusion Melanoma-associated helper peptides paradoxically decreased CD8+ T-cell responses to a melanoma vaccine (P < .001), and CY pretreatment had no immunologic or clinical effect. Prior work showed immunologic and clinical activity of 6MHP alone. Possible explanations for negative effects on CD8 responses include modulation of homing receptor expression or induction of antigen-specific regulatory T cells. PMID:21690475
Bernstein, David I.; Munoz, Flor M.; Callahan, S. Todd; Rupp, Richard; Wootton, Susan H.; Edwards, Kathryn M.; Turley, Christine B.; Stanberry, Lawrence R.; Patel, Shital M.; Mcneal, Monica M.; Pichon, Sylvie; Amegashie, Cyrille; Bellamy, Abbie R
Background Cytomegalovirus (CMV) is a leading cause of congenital infection and an important target for vaccine development. Methods CMV seronegative girls between 12 and 17 years of age received CMV glycoprotein B (gB) vaccine with MF59 or saline placebo at 0, 1 and 6 months. Blood and urine were collected throughout the study for evidence of CMV infection based on PCR and/or seroconversion to non-vaccine CMV antigens. Results 402 CMV seronegative subjects were vaccinated (195 vaccine, 207 placebo). The vaccine was generally well tolerated, although local and systemic adverse events were significantly more common in the vaccine group. The vaccine induced gB antibody in all vaccine recipients with a gB geometric mean titer of 13,400 EU; 95%CI 11,436, 15,700, after 3 doses. Overall, 48 CMV infections were detected (21 vaccine, 27 placebo). In the per protocol population (124 vaccine, 125 placebo) vaccine efficacy was 43%; 95% CI: −36; 76, P=0.20. The most significant difference was after 2 doses, administered as per protocol; vaccine efficacy 45%, 95% CI: −9; 72, P=0.08. Conclusion The vaccine was safe and immunogenic. Although the efficacy did not reach conventional levels of significance, the results are consistent with a previous study in adult women (Pass et al NEJM 360:1191, 2009) using the same formulation. PMID:26657184
Sciutto, E; Morales, J; Martínez, J J; Toledo, A; Villalobos, M N; Cruz-Revilla, C; Meneses, G; Hernández, M; Díaz, A; Rodarte, L F; Acero, G; Gevorkian, G; Manoutcharian, K; Paniagua, J; Fragoso, G; Fleury, A; Larralde, R; De Aluja, A S; Larralde, C
Taenia solium cysticercosis is a parasitic disease frequently affecting human health and the pig industry in many developing countries. A synthetic peptide vaccine (designated S3Pvac) against porcine cysticercosis has been developed previously as an aid to interrupt transmission and has been shown to be effective. The results of the present study support the effectiveness of the vaccine under endemic field conditions. However, given the time-frame of the vaccination trial, no changes in the local levels of transmission were detectable before and after vaccination using sentinel pigs. Thus, this investigation shows the limited usefulness of single vaccination as the sole means of interrupting Taenia solium transmission in an endemic region.
Heery, Christopher R.; Singh, B. Harpreet; Rauckhorst, Myrna; Marté, Jennifer L.; Donahue, Renee N.; Grenga, Italia; Rodell, Timothy C.; Dahut, William; Arlen, Philip M.; Madan, Ravi A.; Schlom, Jeffrey; Gulley, James L.
The nuclear transcription factor brachyury has previously been shown to be a strong mediator of the epithelial-to-mesenchymal transition (EMT) in human carcinoma cells and a strong negative prognostic factor in several tumor types. Brachyury is overexpressed in a range of human carcinoma as well as in chordoma, a rare tumor for which there is no standard systemic therapy. Preclinical studies have shown a recombinant Saccharomyces cerevisiae (yeast) vaccine encoding brachyury (GI-6301) can activate human T cells in vitro. A Phase I dose escalation (3+3 design) trial enrolled 34 patients at 4 dose levels (3, 3, 16, and 11 patients, respectively, at 4, 16, 40, and 80 yeast units (YU)). Expansion cohorts were enrolled at 40 and 80 YU dose levels for analysis of immune response and clinical activity. We observed brachyury-specific T-cell immune responses in the majority of evaluable patients despite most having been heavily pretreated. No evidence of autoimmunity or other serious adverse events were observed. Two chordoma patients showed evidence of disease control (one mixed response and one partial response). A patient with colorectal carcinoma, who enrolled on study with a large progressing pelvic mass and rising CEA, remains on study for greater than 1 year with stable disease, evidence of decreased tumor density and decreased serum CEA. This study is the first-in-human to demonstrate the safety and immunogenicity of this therapeutic cancer vaccine and provides rationale for exploration in Phase II studies. A randomized Phase II chordoma study is enrolling. PMID:26130065
Dyson, E; Voisey, S; Hughes, S; Higgins, B; McQuillan, P
Objectives: Although mnemonics are commonly used in medical education there are few data on their effectiveness. A RCT was undertaken to test the hypothesis that a new aide memoire, "EMD-aide", would be superior to the conventional "4Hs+4Ts" mnemonic in facilitating recall of causes of electromechanical dissociation (EMD) among house officers. Method: "EMD-aide", organises causes of EMD by frequency of occurrence and ease of reversibility: four groups organised by shape, colour, position, numbering, clockwise sequence, and use of arrows. Eight hospitals were randomised in a controlled trial and 149 house officers were then recruited by telephone. Baseline ability to recall causes of EMD was recorded at one minute and overall. House officers were then sent a copy of either "4Hs+4Ts" or "EMD-aide" according to randomisation group. Recall ability was retested at one month. Results: 68 of 80 and 51 of 69 house officers completed the study in the "4Hs+4Ts" and "EMD-aide" groups respectively (NS) with similar baseline recall. After intervention median number of recalled causes was greater in the "EMD-aide" group, eight compared with seven at one minute (p = 0.034) and eight compared with seven overall, p = 0.067. Recall of all eight causes was more common in "EMD-aide" group, 54% compared with 35%, p = 0.054, and these house officers spent longer examining their aide memoire, p<0.001. Conclusions: "EMD-aide" may be superior to "4Hs+4Ts" in facilitating the recall of the causes of electromechanical dissociation. Educational psychology of medical learning and the use of aide memoires in general are worthy of further study. PMID:15208230
Buys, Angela; Macdonald, Raynard; Crafford, Jannie; Theron, Jacques
Enterotoxaemia, an economically important disease of sheep, goats and calves, is caused by systemic effects of the epsilon toxin produced by the anaerobic bacterium Clostridium perfringens type D. The only practical means of controlling the occurrence of enterotoxaemia is to immunise animals by vaccination. The vaccine is prepared by deriving a toxoid from the bacterial culture filtrate and the potency of the vaccine is tested with the in vivo mouse neutralisation test (MNT). Due to ethical, economic and technical reasons, alternative in vitro assays are needed. In this study an indirect cytometric bead immunoassay (I-CBA) was developed for use in vaccine potency testing and the results were compared with those obtained using an indirect enzyme-linked immunosorbent assay (I-ELISA) and the MNT. Sera were collected from guinea pigs immunised with three different production batches of enterotoxaemia vaccine and the levels of anti-epsilon toxin antibodies were determined. Although the intra- and inter-assay variability was satisfactory, epsilon antitoxin levels determined by both the I-ELISA and indirect cytometric bead immunoassay (I-CBA) tests were higher than those of the MNT assay. In contrast to the MNT, all of the serum samples were identified as having antitoxin levels above the required minimum (not less than 5 U/mL). These results indicate that the respective in vitro tests in their current formats are not yet suitable alternatives to the in vivo MNT. The growing demand for a more humane, cost-effective and efficient method for testing the potency of enterotoxaemia vaccines, however, provides a strong impetus for further optimisation and standardisation of the I-CBA assay but further analytical research is required.
Roberts, Kathleen Johnston; Newman, Peter A.; Duan, Naihua; Rudy, Ellen T.
HIV vaccines offer the best long-term hope of controlling the AIDS pandemic. We explored HIV vaccine knowledge and beliefs among communities at elevated risk for HIV/AIDS. Participants (N=99; median age=33 years; 48% female; 22% African-American; 44% Latino; 28% white; 6% other) were recruited from seven high-risk venues in Los Angeles, California, using purposive, venue-based sampling. Results from nine focus groups revealed: 1) mixed beliefs and conspiracy theories about the existence of HIV vaccines; 2) hopefulness and doubts about future HIV vaccine availability; 3) lack of information about HIV vaccines; and 4) confusion about vaccines and how they work. Tailored HIV vaccine education that addresses the current status of HIV vaccine development and key vaccine concepts is warranted among communities at risk. Ongoing dialogue among researchers, public health practitioners and communities at risk may provide a vital opportunity to dispel misinformation and rumors and to cultivate trust, which may facilitate HIV vaccine trial participation and uptake of future HIV vaccines. PMID:16396058
van Doorn, Eva; Hak, Eelko; Wilffert, Bob
Obtaining approval for a multinational vaccine trial from an ethics committee and the national competent authority of different Member States of the European Union (EU) is challenging under clinical trial Directive 2001/20/EC because of the differences in the implementation of the directive in national laws of Member States. In this review the national differences in requirements for ethical and competent authority approval are illustrated. The national ethical and competent authority review procedures in Finland, Hungary, The Netherlands, No