Development of an in vitro chemo-radiation response assay for cervical carcinoma.

PubMed

Monk, Bradley J; Burger, Robert A; Parker, Ricardo; Radany, Eric H; Redpath, Leslie; Fruehauf, John P

2002-11-01

To determine if synergistic effects of radiation (RT) and chemotherapy (chemo) on human cervical carcinoma cell lines and fresh tumor explants could be determined using an in vitro assay. In vitro radiation response was determined for 4 cell lines and 26 fresh tumor explants in an agar-based assay. Cells were exposed to increasing doses of RT with or without cisplatin (CDDP), carmustine (BCNU), buthionine sulfoximine (BSO), or paclitaxel (Tax). Cell suspensions were cultured for 5 days, with [(3)H]thymidine added on day 3 and proliferation was measured. Results were reported as the fraction of proliferation compared to control (FC). For each combination of irradiation and drug, synergy was tested using the Chou analysis, where a combination index (CI) <1 indicated synergistic interaction. In simple correlation analysis, an R value of >0.7 indicated cross-resistance. RT dose-dependent proliferation inhibition was observed for 2 of the 4 cell lines, and for all but 1 of the fresh specimens. Significant heterogeneity of tumor response to RT was seen. Four specimens that were 1 standard deviation below the median FC response after exposure to 300 cGy were classified as extremely radiation resistant. Twenty-one tumors were evaluated for synergistic response using the combination of chemo and RT with a median FC of 0.27 (+/-0.27) for 6.0 Gy of RT alone, 0.22 (+/-0.21) for CDDP alone, and 0.05 (+/-0.08) for the combination. A CI of 0.35 and an R value of 0.09 demonstrated synergy between chemo and RT without cross-resistance. Similar synergy without cross-resistance was found for RT in combination with BCNU, BSO, and TAX. Heterogeneous RT dose-response relationships in the in vitro assay were demonstrated. Explants were more sensitive to RT than cell lines. Unlike cell lines, fresh tumor cells consistently displayed synergy with RT and chemo. The synergy between RT and BSO suggests that glutathione depletion may enhance the effect of RT. The assay was feasible for examining fresh tumors and may be an important tool for studying RT or drug resistance. Clinical trials to evaluate this assay are indicated.

In vivo Selection of Autologous MGMT Gene-Modified Cells Following Reduced Intensity Conditioning with BCNU and Temozolomide in the Dog Model

PubMed Central

Gori, Jennifer L.; Beard, Brian C.; Ironside, Christina; Karponi, Garyfalia; Kiem, Hans-Peter

2012-01-01

Chemotherapy with BCNU and temozolomide (TMZ) is commonly used for the treatment of glioblastoma multiforme (GBM) and other cancers. In preparation for a clinical gene therapy study in patients with glioblastoma, we wished to study whether these reagents could be used as a reduced-intensity conditioning regimen for autologous transplantation of gene-modified cells. We used an MGMT(P140K)-expressing lentivirus vector to modify dog CD34+ cells and tested in 4 dogs whether these autologous cells engraft and provide chemoprotection after transplantation. Treatment with O6-benzylguanine (O6BG)/TMZ after transplantation resulted in gene marking levels up to 75%, without significant hematopoietic cytopenia, which is consistent with hematopoietic chemoprotection. Retrovirus integration analysis showed that multiple clones contribute to hematopoiesis. These studies demonstrate the ability to achieve stable engraftment of MGMT(P140K)-modified autologous HSCs after a novel reduced-intensity conditioning protocol using a combination of BCNU and TMZ. Furthermore, we show that MGMT(P140K)-HSC engraftment provides chemoprotection during TMZ dose escalation. Clinically, chemoconditioning with BCNU and TMZ should facilitate engraftment of MGMT(P140K)-modified cells while providing anti-tumor activity for patients with poor prognosis glioblastoma or alkylating agent sensitive tumors, thereby supporting dose-intensified chemotherapy regimens. PMID:22627392

Effect of treatment in fractionated schedules with the combination of x-irradiation and six cytotoxic drugs on the RIF-1 tumor and normal mouse skin

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

Lelieveld, P.; Scoles, M.A.; Brown, J.M.

1985-01-01

RIF-1 tumors, implanted syngeneically in the gastrocnemius muscles of the right hind legs of C3H/Km mice, were treated either with X ray alone, drug alone, or drug and X ray combined. The drugs tested were bleomycin, BCNU, cis-diamminedichloro platinum, adriamycin, cyclophosphamide, and actinomycin-D. All drugs were administered either in the maximum tolerated dose or a dose that causes minimal tumor growth delay. Both drugs and X rays were administered either as a single dose or in five daily fractions. In addition to the single modality controls, seven different schedules of combined modalities were tested. Tumors were measured periodically after treatmentmore » in order that the day at which each tumor reached 4 times its initial cross-sectional area, i.e., its size at the time of treatment, could be determined. The effect of treatment on tumors was based upon excess growth delay (GD), i.e., T400% (treated)-T400% (untreated control). Treatment effects for the same combined modality schedules were also determined for normal skin, using the early skin reaction as an endpoint. Dose effect factors (DEF) were computed for all combined modality schedules and were based upon calculated radiation dose equivalents. We also calculated supra-additivity ratios, SR/sub I/ and SR/sub II/, therapeutic gain factors and adjusted therapeutic gain factors. The only drugs to produce significant supra-additivity with X rays were cis-Pt and cyclo.« less

A Multicenter Phase I/II Study of the BCNU Implant (Gliadel ® Wafer) for Japanese Patients with Malignant Gliomas

PubMed Central

AOKI, Tomokazu; NISHIKAWA, Ryo; SUGIYAMA, Kazuhiko; NONOGUCHI, Naosuke; KAWABATA, Noriyuki; MISHIMA, Kazuhiko; ADACHI, Jun-ichi; KURISU, Kaoru; YAMASAKI, Fumiyuki; TOMINAGA, Teiji; KUMABE, Toshihiro; UEKI, Keisuke; HIGUCHI, Fumi; YAMAMOTO, Tetsuya; ISHIKAWA, Eiichi; TAKESHIMA, Hideo; YAMASHITA, Shinji; ARITA, Kazunori; HIRANO, Hirofumi; YAMADA, Shinobu; MATSUTANI, Masao

2014-01-01

Carmustine (BCNU) implants (Gliadel® Wafer, Eisai Inc., New Jersey, USA) for the treatment of malignant gliomas (MGs) were shown to enhance overall survival in comparison to placebo in controlled clinical trials in the United States and Europe. A prospective, multicenter phase I/II study involving Japanese patients with MGs was performed to evaluate the efficacy, safety, and pharmacokinetics of BCNU implants. The study enrolled 16 patients with newly diagnosed MGs and 8 patients with recurrent MGs. After the insertion of BCNU implants (8 sheets maximum, 61.6 mg BCNU) into the removal cavity, various chemotherapies (including temozolomide) and radiotherapies were applied. After placement, overall and progression-free survival rates and whole blood BCNU levels were evaluated. In patients with newly diagnosed MGs, the overall survival rates at 12 months and 24 months were 100.0% and 68.8%, and the progression-free survival rate at 12 months was 62.5%. In patients with recurrent MGs, the progression-free survival rate at 6 months was 37.5%. There were no grade 4 or higher adverse events noted due to BCNU implants, and grade 3 events were observed in 5 of 24 patients (20.8%). Whole blood BCNU levels reached a peak of 19.4 ng/mL approximately 3 hours after insertion, which was lower than 1/600 of the peak BCNU level recorded after intravenous injections. These levels decreased to less than the detection limit (2.00 ng/mL) after 24 hours. The results of this study involving Japanese patients are comparable to those of previous studies in the United States and Europe. PMID:24739422

Outcome of patients affected by newly diagnosed glioblastoma undergoing surgery assisted by 5-aminolevulinic acid guided resection followed by BCNU wafers implantation: a 3-year follow-up.

PubMed

Della Puppa, Alessandro; Lombardi, Giuseppe; Rossetto, Marta; Rustemi, Oriela; Berti, Franco; Cecchin, Diego; Gardiman, Marina Paola; Rolma, Giuseppe; Persano, Luca; Zagonel, Vittorina; Scienza, Renato

2017-01-01

The purpose of the study was to evaluate the clinical outcome of the association of BCNU wafers implantation and 5-aminolevulinic acid (5-ALA) fluorescence in the treatment of patients with newly diagnosed glioblastoma (ndGBM). Clinical and surgical data from patients who underwent 5-ALA surgery followed by BCNU wafers implantation were retrospectively evaluated (20 patients, Group I) and compared with data of patients undergoing surgery with BCNU wafers alone (42 patients, Group II) and 5-ALA alone (59 patients, Group III). Patients undergoing 5-ALA assisted resection followed by BCNU wafers implantation (Group I) resulted long survivors (>3 years) in 15 % of cases and showed a median PFS and MS of 11 and 22 months, respectively. Patients treated with BCNU wafers presented a significantly higher survival when tumor was removed with the assistance of 5-ALA (22 months with vs 18 months without 5-ALA, p < 0.0001); these data could be partially explained by the significantly higher CRET achieved in patients operated with 5-ALA assistance (80 % with vs 47 %% without 5-ALA). Moreover, patients of Group I showed a significant increased survival compared with Group III (5-ALA without BCNU) (22 months with vs 21 months without BCNU wafers, p = 0.0025) even with a comparable CRET (80 % vs 76 %, respectively). The occurrence of adverse events related to wafers did not significantly increase with 5-ALA (20 % with and 19 % without 5-ALA) and did not impact in survival outcome. In conclusion, our experience shows that on selected ndGBM patients 5-ALA technology and BCNU wafers implantation show a synergic action on patients' outcome without increasing adverse events occurrence.

Phase II trial of carmustine plus O(6)-benzylguanine for patients with nitrosourea-resistant recurrent or progressive malignant glioma.

PubMed

Quinn, Jennifer A; Pluda, James; Dolan, M Eileen; Delaney, Shannon; Kaplan, Richard; Rich, Jeremy N; Friedman, Allan H; Reardon, David A; Sampson, John H; Colvin, O Michael; Haglund, Michael M; Pegg, Anthony E; Moschel, Robert C; McLendon, Roger E; Provenzale, James M; Gururangan, Sridharan; Tourt-Uhlig, Sandra; Herndon, James E; Bigner, Darell D; Friedman, Henry S

2002-05-01

We conducted a phase II trial of carmustine (BCNU) plus the O(6)-alkylguanine-DNA alkyltransferase inhibitor O(6)-benzylguanine (O(6)-BG) to define the activity and toxicity of this regimen in the treatment of adults with progressive or recurrent malignant glioma resistant to nitrosoureas. Patients were treated with O(6)-BG at an intravenous dose of 120 mg/m(2) followed 1 hour later by 40 mg/m(2) of BCNU, with cycles repeated at 6-week intervals. Eighteen patients were treated (15 with glioblastoma multiforme, two with anaplastic astrocytoma, and one with malignant glioma). None of the 18 patients demonstrated a partial or complete response. Two patients exhibited stable disease for 12 weeks before their tumors progressed. Three patients demonstrated stable disease for 6, 12, and 18 weeks before discontinuing therapy because of hematopoietic toxicity. Twelve patients experienced reversible > or = grade 3 hematopoietic toxicity. There was no difference in half-lives (0.56 +/- 0.21 hour v 0.54 +/- 0.20 hour) or area under the curve values (4.8 +/- 1.7 microg/mL/h v 5.0 +/- 1.3 microg/mL/h) of O(6)-BG for patients receiving phenytoin and those not treated with this drug. These results indicate that O(6)-BG plus BCNU at the dose schedule used in this trial is unsuccessful in producing tumor regression in patients with nitrosourea-resistant malignant glioma, although stable disease was seen in five patients for 6, 12, 12, 12, and 18 weeks. Future use of this approach will require strategies to minimize dose-limiting toxicity of BCNU such as regional delivery or hematopoietic stem-cell protection.

Genetic modification of haematopoietic cells for combined resistance to podophyllotoxins, other agents covered by MDR1-mediated efflux activity and nitrosoureas.

PubMed

Baum, C; Peinert, S; Carpinteiro, A; Eckert, H G; Fairbairn, L J

2000-05-01

Genetic transfer and expression of drug-resistance functions into haematopoietic stem and progenitor cells is a promising means to overcome both the acute and longterm side-effects of cytotoxic drugs in bone marrow. Here, we describe a functional analysis of a retroviral vector that co-expresses human cDNAs for multidrug resistance 1/P-glycoprotein (MDR1) and a double mutant of O(6)-alkylguanine-alkyltransferase (hATPA/GA) to high levels. The hATPA/GA protein contains two amino acid substitutions that render it resistant to compounds such as O(6)-benzylguanine that inhibit the wild-type protein which is often overexpressed in resistant tumour cells. Evidence for simultaneous drug resistance of genetically modified primary murine progenitor cells to colchicine or the podophyllotoxin etoposide, both covered by MDR1-mediated efflux activity, and the nitrosourea BCNU, which is counteracted by hATPA/GA, is presented using in vitro colony assays.

Patterns of cross-sensitivity in the responses of clonal subpopulations isolated from the RIF-1 mouse sarcoma to selected nitrosoureas and nitrogen mustards.

PubMed Central

Reeve, J. G.; Wright, K. A.; Workman, P.

1984-01-01

The response of clonal subpopulations isolated from the RIF-1 mouse sarcoma to melphalan treatment is independent of cell ploidy, whereas a clear relationship exists between ploidy and cell sensitivity to CCNU treatment. In the present study RIF-1 clones have been exposed to nitrogen mustard, aniline mustard and chlorambucil, and to nitrosoureas BCNU, MeCCNU and chlorozotocin, in order to evaluate whether or not the different physiochemical and biological activities of these agents would affect the patterns of drug sensitivity obtained for melphalan and CCNU. Irrespective of the different lipophilicities, transport properties and chemical reactivities of the nitrogen mustards, RIF-1 clones showed the same pattern of sensitivity as previously observed for melphalan. Similarly, RIF-1 clones when exposed to nitrosoureas BCNU, MeCCNU and chlorozotocin, showed the same pattern of sensitivity as that obtained for CCNU exposure. These data suggest (a) that the variation in the sensitivity of RIF-1 clones to treatment by the nitrogen mustards is unlikely to reflect differences in either membrane permeability or in drug transport and (b) that the ploidy dependent nitrosourea responses shown by RIF-1 clones similarly do not reflect differences in drug uptake. PMID:6466534

BCNU wafer placement with temozolomide (TMZ) in the immediate postoperative period after tumor resection followed by radiation therapy with TMZ in patients with newly diagnosed high grade glioma: final results of a prospective, multi-institutional, phase II trial.

PubMed

Burri, Stuart H; Prabhu, Roshan S; Sumrall, Ashley L; Brick, Wendy; Blaker, Brian D; Heideman, Brent E; Boltes, Peggy; Kelly, Renee; Symanowski, James T; Wiggins, Walter F; Ashby, Lynn; Norton, H James; Judy, Kevin; Asher, Anthony L

2015-06-01

Temozolomide (TMZ) and BCNU have demonstrated anti-glioma synergism in preclinical models. We report final data from a prospective, multi-institutional study of BCNU wafers and early TMZ followed by radiation therapy with TMZ in patients with newly diagnosed malignant glioma. 65 patients were consented in 4 institutions, and 46 patients (43 GBM, 3 AA) were eligible for analysis. After resection and BCNU wafer placement, TMZ began on day four postoperatively. Radiation and TMZ (RT/TMZ) were then administered, followed by monthly TMZ at 200 mg/m2 for the first 26 patients, which was reduced to 150 mg/m2 for the remaining 20 patients. Non-hematologic toxicities were minimal. Nine of 27 patients (33 %) who received 200 mg/m2 TMZ, but only 1 of 20 (5 %) who received 150 mg/m2, experienced grade 3/4 thrombocytopenia. Median progression free survival (PFS) and overall survival (OS) period was 8.5 and 18 months, respectively. The 1-year OS rate was 76 %, which is a significant improvement compared with the historical control 1-year OS rate of 59 % (p = 0.023). However, there was no difference in 1-year OS compared with standard RT/TMZ (p = 0.12) or BCNU wafer followed by RT/TMZ (p = 0.87) in post hoc analyses. Early post-operative TMZ can be safely administered with BCNU wafers following resection of malignant glioma at the 150 mg/m2 dose level. Although there was an OS benefit compared to historical control, there was no indication of benefit for BCNU wafers and early TMZ in addition to standard RT/TMZ or early TMZ in addition to regimens of BCNU wafers followed by RT/TMZ.

Increased pCREB expression and the spontaneous epileptiform activity in a BCNU-treated rat model of cortical dysplasia.

PubMed

Pennacchio, Paolo; Noé, Francesco; Gnatkovsky, Vadym; Moroni, Ramona Frida; Zucca, Ileana; Regondi, Maria Cristina; Inverardi, Francesca; de Curtis, Marco; Frassoni, Carolina

2015-09-01

Cortical dysplasias (CDs) represent a wide range of cortical abnormalities that closely correlate with intractable epilepsy. Rats prenatally exposed to 1-3-bis-chloroethyl-nitrosurea (BCNU) represent an injury-based model that reproduces many histopathologic features of human CD. Previous studies reported in vivo hyperexcitability in this model, but in vivo epileptogenicity has not been confirmed. To determine whether cortical and hippocampal lesions lead to epileptiform discharges and/or seizures in the BCNU model, rats at three different ages (3, 5, and 9 months old) were implanted for long-term video electroencephalographic recording. At the end of the recording session, brain tissue was processed for histologic and immunohistochemical investigation including cAMP response element binding protein (CREB) phosphorylation, as a biomarker of epileptogenicity. BCNU-treated rats showed spontaneous epileptiform activity (67%) in the absence of a second seizure-provoking hit. Such activity originated mainly from one hippocampus and propagated to the ipsilateral neocortex. No epileptiform activity was found in age-matched control rats. The histopathologic investigation revealed that all BCNU rats with epileptiform activity showed neocortical and hippocampal abnormalities; the presence and the severity of these lesions did not correlate consistently with the propensity to generate epileptiform discharges. Epileptiform activity was found only in cortical areas of BCNU-treated rats in which a correlation between brain abnormalities and increased pCREB expression was observed. This study demonstrates the in vivo occurrence of spontaneous epileptiform discharges in the BCNU model and shows that increased pCREB expression can be utilized as a reliable biomarker of epileptogenicity. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

The effect of trimetazidine on intrahepatic cholestasis caused by carmustine in rats.

PubMed

Demir, A; Özütemiz, O; Yildiz, C; Yüce, G; Tekeşin, O; Ilter, T

2001-05-01

This study investigated the effect of trimetazidine (TMZ), known as an anti-oxidant agent, on intrahepatic cholestasis caused by Carmustine (BCNU) in rats. Rats were assigned into four groups. The first group (Saline) consisted of 12 rats, which were injected with 2 ml/kg of saline intraperitoneally (IP) 48 h before the study. The second group (corn oil group, n=15), which were injected with 2 ml/kg of corn oil IP 48 h before the study. The third group (BCNU group, n=16), which were injected with 2 ml/kg of corn oil+25 mg/kg BCNU IP 48 h before the study. The fourth group (TMZ group, n=12), which were injected with 2.5 mg/kg per day of TMZ IP, administered at the same hour of the day as a single-dose. Twelve hour after the first dose of TMZ, corn oil 2 ml/kg+BCNU 25 mg/kg IP were injected, and the rats were included in the study 48 h after the administration of corn oil+BCNU. Following a pentobarbital anaesthesia, abdomen was opened with incision, a cannula was placed into the channel of choledocus, and the amount of bile was measured per hour. Then intracardiac blood sample was taken, and consequently centrifuged to obtain the plasma. Finally, the rats were killed with cervical dislocation, and their livers were removed and weighted. In addition to histopathological examination of liver, the levels of malon dialdehyde (MDA), oxidised glutation (GSSG), and reduced glutation (GSH) were detected. Also the osmolality of bile and plasma was estimated in mOsm/kg. As a result, the biliary flow was seen to decrease in BCNU group (P<0.005), but to be normal in TMZ group. The serum level of conjugated biluribin was higher in BCNU group compared to other groups (P<0.05 for each). Although the level of total glutation was lower (P<0.005) in TMZ group, GSH/GSSG ratio was normal. These findings suggest that TMZ has a protective effect on intrahepatic cholestasis caused by BCNU.

Involvement of the immune response in the cure of metastatic murine CT-26 colon carcinoma by low electric field-enhanced chemotherapy.

PubMed

Plotnikov, Alexander; Tichler, Thomas; Korenstein, Rafi; Keisari, Yona

2005-12-10

Low electric field cancer treatment-enhanced chemotherapy (LEFCT-EC) is a new treatment modality that combines chemotherapeutic agents and low electric field stimulation. LEFCT-EC was found to destroy malignant mouse tumors and cause massive death of tumor cells. This may enable the immune system cells to efficiently recognize and eliminate tumor cells at the primary tumor site and at metastatic foci. Mice with 15 mm diameter intracutaneous colon carcinomas (CT-26) were injected with BCNU (35 mg/kg), and 2 min later the tumors were exposed to low electric fields (intensity 40 V/cm, pulse duration 180 micros, frequency 500 Hz) for 12 min (LEFCT-EC). We found that treatment with LEFCT-EC achieved complete cure of 93% of the animals. In comparison, electric fields alone (13% cure), chemotherapy alone (0%), surgery (15%) or a combination of surgery and bis-chloroethyl-nitrosurea, carmustine (BCNU; 84%) treatments resulted in lower cure rates. After treatment and cure with LEFCT-EC, 50% of the cured mice developed resistance to a tumor challenge (surgery + BCNU only 15%). Furthermore, splenocytes from cured animals protected naive animals from a tumorigenic dose of tumor cells. Separation of spleen cells into lymphocyte subpopulations indicated a major role for CD4 and CD8 T cells in this protection. FACS analysis revealed restoration of normal splenocyte subpopulation proportions impaired by cytotoxic chemotherapy. Our results suggest that LEFCT-EC can directly destroy primary tumors and facilitate the destruction of metastatic disease by enforcement of antitumor immune responses. Copyright 2005 Wiley-Liss, Inc

Determination of nitrosourea compounds in brain tissue by gas chromatography and electron capture detection.

PubMed

Hassenbusch, S J; Colvin, O M; Anderson, J H

1995-07-01

A relatively simple, high-sensitivity gas chromatographic assay is described for nitrosourea compounds, such as BCNU [1,3-bis(2-chloroethyl)-1-nitrosourea] and MeCCNU [1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea], in small biopsy samples of brain and other tissues. After extraction with ethyl acetate, secondary amines in BCNU and MeCCNU are derivatized with trifluoroacetic anhydride. Compounds are separated and quantitated by gas chromatography using a capillary column with temperature programming and an electron capture detector. Standard curves of BCNU indicate a coefficient of variance of 0.066 +/- 0.018, a correlation coefficient of 0.929, and an extraction efficiency from whole brain of 68% with a minimum detectable amount of 20 ng in 5-10 mg samples. The assay has been facile and sensitive in over 1000 brain biopsy specimens after intravenous and intraarterial infusions of BCNU.

The Fanconi anemia (FA) pathway confers glioma resistance to DNA alkylating agents.

PubMed

Chen, Clark C; Taniguchi, Toshiyasu; D'Andrea, Alan

2007-05-01

DNA alkylating agents including temozolomide (TMZ) and 1,3-bis[2-chloroethyl]-1-nitroso-urea (BCNU) are the most common form of chemotherapy in the treatment of gliomas. Despite their frequent use, the therapeutic efficacy of these agents is limited by the development of resistance. Previous studies suggest that the mechanism of this resistance is complex and involves multiple DNA repair pathways. To better define the pathways contributing to the mechanisms underlying glioma resistance, we tested the contribution of the Fanconi anemia (FA) DNA repair pathway. TMZ and BCNU treatment of FA-proficient cell lines led to a dose- and time-dependent increase in FANCD2 mono-ubiquitination and FANCD2 nuclear foci formation, both hallmarks of FA pathway activation. The FA-deficient cells were more sensitive to TMZ/BCNU relative to their corrected, isogenic counterparts. To test whether these observations were pertinent to glioma biology, we screened a panel of glioma cell lines and identified one (HT16) that was deficient in the FA repair pathway. This cell line exhibited increased sensitivity to TMZ and BCNU relative to the FA-proficient glioma cell lines. Moreover, inhibition of FA pathway activation by a small molecule inhibitor (curcumin) or by small interference RNA suppression caused increased sensitivity to TMZ/BCNU in the U87 glioma cell line. The BCNU sensitizing effect of FA inhibition appeared additive to that of methyl-guanine methyl transferase inhibition. The results presented in this paper underscore the complexity of cellular resistance to DNA alkylating agents and implicate the FA repair pathway as a determinant of this resistance.

Imaging in real-time with FRET the redox response of tumorigenic cells to glutathione perturbations in a microscale flow†

PubMed Central

Lin, Chunchen; Kolossov, Vladimir L.; Tsvid, Gene; Trump, Lisa; Henry, Jennifer Jo; Henderson, Jerrod L.; Rund, Laurie A.; Kenis, Paul J.A.; Schook, Lawrence B.; Gaskins, H. Rex; Timp, Gregory

2012-01-01

Despite the potential benefits of selective redox-modulating strategies for cancer therapy, an efficacious methodology for testing therapies remains elusive because of the difficulty in measuring intracellular redox potentials over time. In this report, we have incorporated a new FRET-based biosensor to follow in real time redox-sensitive processes in cells transformed to be tumorigenic and cultured in a microfluidic channel. A microfluidic network was used to control micro-scale flow near the cells and at the same time deliver drugs exogenously. Subsequently, the response of a redox homeostasis circuit was tested, namely reduced glutathione (GSH)/oxidized glutathione(GSSG), to diamide, a thiol oxidant, and two drugs used for cancer therapies: BSO (l-buthionine-[SR]-sulfoximine) and BCNU (carmustine). The main outcome from these experiments is a comparison of the temporal depletion and recovery of GSH in single living cells in real-time. These data demonstrate that mammalian cells are capable of restoring a reduced intracellular redox environment in minutes after an acute oxidative insult is removed. This recovery is significantly delayed by (i) the inhibition of GSH biosynthesis by BSO; (ii) the inactivation of glutathione reductase by BCNU; and (iii) in tumorigenic cells relative to an isogenic non-tumorigenic control cell line. PMID:21183971

Nitrosourea efficacy in high-grade glioma: a survival gain analysis summarizing 504 cohorts with 24193 patients.

PubMed

Wolff, Johannes E A; Berrak, Su; Koontz Webb, Susannah E; Zhang, Ming

2008-05-01

Even though past studies have suggested efficacy of nitrosourea drugs in patients with high-grade glioma and temozolomide has recently been shown significantly to be beneficial, no conclusive comparisons between these agents have been published. We performed a survival gain analysis of 364 studies describing 24,193 patients with high-grade glioma treated in 504 cohorts, and compared the effects of drugs. The most frequent diagnoses were glioblastoma multiforme (GBM) (72%) and anaplastic astrocytoma (22%). The mean overall survival (mOS) was 14.1 months. The outcome was influenced by several of the known prognostic factors including the histological grade, if the tumors were newly diagnosed or recurrent, the completeness of resection, patients' age, and gender. This information allowed the calculation of a predicted mOS for each cohort based on their prognostic factors independent of treatment. Survival gain to characterize the influence of treatment was subsequently defined and validated as the difference between the observed and the predicted mOS. In 62 CCNU-treated cohorts and 15 ACNU-treated cohorts the survival gain was 5.3 months and 8.9 months (P < 0.0005), respectively. No detectable survival gain for patients treated with various BCNU-containing regimens was found. Conclusion CCNU- and ACNU-containing regimens were superior to BCNU containing regiments.

Low electric field enhanced chemotherapy can cure mice with CT-26 colon carcinoma and induce anti-tumour immunity

PubMed Central

PLOTNIKOV, A; FISHMAN, D; TICHLER, T; KORENSTEIN, R; KEISARI, Y

2004-01-01

Low electric field cancer treatment − enhanced chemotherapy (LEFCT-EC) is a new anticancer treatment which utilizes a combination of chemotherapeutic agents and a low electric field. We investigated the antitumour effectiveness of this technique in a model of murine colon carcinoma (CT-26). The low electric field was applied to ∼65 mm3 intracutaneous tumours after intratumoral injection of 5FU, bleomycin or BCNU. We observed significant tumour size reduction and a prolongation of survival time. The complete cure of a significant fraction of animals treated by LEFCT-EC with 5FU (33%), bleomycin (51%) or BCNU (83%) was observed. Mice cured by LEFCT-EC developed resistance to a tumour challenge and their splenocytes had antitumour activity in vivo. Our results suggest that LEFCT-EC is an effective method for treatment of solid tumours. PMID:15544616

Low electric field enhanced chemotherapy can cure mice with CT-26 colon carcinoma and induce anti-tumour immunity.

PubMed

Plotnikov, A; Fishman, D; Tichler, T; Korenstein, R; Keisari, Y

2004-12-01

Low electric field cancer treatment-enhanced chemotherapy (LEFCT-EC) is a new anticancer treatment which utilizes a combination of chemotherapeutic agents and a low electric field. We investigated the antitumour effectiveness of this technique in a model of murine colon carcinoma (CT-26). The low electric field was applied to approximately 65 mm3 intracutaneous tumours after intratumoral injection of 5FU, bleomycin or BCNU. We observed significant tumour size reduction and a prolongation of survival time. The complete cure of a significant fraction of animals treated by LEFCT-EC with 5FU (33%), bleomycin (51%) or BCNU (83%) was observed. Mice cured by LEFCT-EC developed resistance to a tumour challenge and their splenocytes had antitumour activity in vivo. Our results suggest that LEFCT-EC is an effective method for treatment of solid tumours.

Hydroxyapatite nanoparticles inhibit the growth of human glioma cells in vitro and in vivo.

PubMed

Chu, Sheng-Hua; Feng, Dong-Fu; Ma, Yan-Bin; Li, Zhi-Qiang

2012-01-01

Hydroxyapatite nanoparticles (nano-HAPs) have been reported to exhibit antitumor effects on various human cancers, but the effects of nano-HAPs on human glioma cells remain unclear. The aim of this study was to explore the inhibitory effect of nano-HAPs on the growth of human glioma U251 and SHG44 cells in vitro and in vivo. Nano-HAPs could inhibit the growth of U251 and SHG44 cells in a dose- and time-dependent manner, according to methyl thiazoletetrazolium assay and flow cytometry. Treated with 120 mg/L and 240 mg/L nano-HAPs for 48 hours, typical apoptotic morphological changes were noted under Hoechst staining and transmission electron microscopy. The tumor growth of cells was inhibited after the injection in vivo, and the related side effects significantly decreased in the nano-HAP-and-drug combination group. Because of the function of nano-HAPs, the expression of c-Met, SATB1, Ki-67, and bcl-2 protein decreased, and the expression of SLC22A18 and caspase-3 protein decreased noticeably. The findings indicate that nano-HAPs have an evident inhibitory action and induce apoptosis of human glioma cells in vitro and in vivo. In a drug combination, they can significantly reduce the adverse reaction related to the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU).

Hydroxyapatite nanoparticles inhibit the growth of human glioma cells in vitro and in vivo

PubMed Central

Chu, Sheng-Hua; Feng, Dong-Fu; Ma, Yan-Bin; Li, Zhi-Qiang

2012-01-01

Hydroxyapatite nanoparticles (nano-HAPs) have been reported to exhibit antitumor effects on various human cancers, but the effects of nano-HAPs on human glioma cells remain unclear. The aim of this study was to explore the inhibitory effect of nano-HAPs on the growth of human glioma U251 and SHG44 cells in vitro and in vivo. Nano-HAPs could inhibit the growth of U251 and SHG44 cells in a dose- and time-dependent manner, according to methyl thiazoletetrazolium assay and flow cytometry. Treated with 120 mg/L and 240 mg/L nano-HAPs for 48 hours, typical apoptotic morphological changes were noted under Hoechst staining and transmission electron microscopy. The tumor growth of cells was inhibited after the injection in vivo, and the related side effects significantly decreased in the nano-HAP-and-drug combination group. Because of the function of nano-HAPs, the expression of c-Met, SATB1, Ki-67, and bcl-2 protein decreased, and the expression of SLC22A18 and caspase-3 protein decreased noticeably. The findings indicate that nano-HAPs have an evident inhibitory action and induce apoptosis of human glioma cells in vitro and in vivo. In a drug combination, they can significantly reduce the adverse reaction related to the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). PMID:22888225

Effects of antineoplastic drugs on Lactobacillus casei and radioisotopic assays for serum folate

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

Carmel, R.

1978-02-01

Microbiologic assay, usually employing Lactobacillus casei, remains the standard assay for serum folate to date. Among its disadvantages have been falsely low results in patients receiving bacteriostatic agents such as antibiotics. This study examined whether commonly used antineoplastic drugs had similar effect. Methotrexate and 5-fluorouracil depressed microbiologic serum folate levels. No effect was found for adriamycin, bleomycin, BCNU, cyclophosphamide, cytosine arabinoside, vincristine, vinblastine, mechlorethamine, mithramycin, hydroxyurea, and hydrocortisone. None of the drugs affected radioassay except methotrexate, which produced falsely high folate results. Thus, it appears that L. casei assay for folate becomes unreliable in patients receiving 5-fluorouracil and radioisotopic assaymore » becomes unreliable in those receiving methotrexate.« less

The effectiveness and cost-effectiveness of carmustine implants and temozolomide for the treatment of newly diagnosed high-grade glioma: a systematic review and economic evaluation.

PubMed

Garside, R; Pitt, M; Anderson, R; Rogers, G; Dyer, M; Mealing, S; Somerville, M; Price, A; Stein, K

2007-11-01

To assess the clinical and cost-effectiveness of adjuvant carmustine wafers (BCNU-W) and also of adjuvant and concomitant temozolomide (TMZ), compared with surgery with radiotherapy. Electronic databases were searched up to August 2005. Included trials were critically appraised for key elements of internal and external validity. Relevant data were extracted and a narrative synthesis of the evidence produced. Where possible, data on absolute survival at a fixed time point were meta-analysed using a random effects model. A Markov (state transition) model was developed to assess the cost-utility of the two interventions. The model compared BCNU-W or TMZ separately with current standard treatment with surgery and radiotherapy. The simulated cohort had a mean age of 55 years and was modelled over 5 years. Two randomised controlled trials (RCTs) (n = 32, n = 240) and two observational studies of BCNU-W compared with placebo wafers as adjuvant therapy to surgery and radiotherapy for newly diagnosed high-grade glioma were identified. All the studies were in adults and provided data on 193 patients who had received BCNU-W. The RCT findings excluded under 65-year-olds and those with a Karnofsky Performance Status of less than 60. The largest multi-centre RCT suggested a possible survival advantage with BCNU-W among a cohort of patients with grade III and IV tumours, adding a median of 2.3 months [95% confidence interval (CI) -0.5 to 5.1]. However, analysis using per-protocol, unstratified methods shows this difference to be not statistically significant (HR 0.77, 95% CI 0.57 to 1.03, p = 0.08). Long-term follow-up suggests a significant survival advantage using unstratified analysis. No difference in progression-free survival (PFS) was demonstrated. Subgroup analysis of those with grade IV tumours also showed no significant survival advantage with BCNU-W [hazard ratio (HR) 0.82, 95% CI 0.55 to 1.11, p = 0.20, unstratified analysis]. It is estimated that the cost of surgery and radiotherapy, with follow-up, treatment of adverse effects and end of life care is around 17,000 pounds per patient. Treatment with BCNU-W adds an additional 6600 pounds. Across the modelled cohort of 1000 patients, use of BCNU-W costs an additional 6.6 million pounds and confers an additional 122 quality-adjusted life-years (QALYs). On average, that is 6600 pounds per patient for 0.122 QALYs (6.3 quality-adjusted life-weeks). The base-case incremental cost-effectiveness ratio (ICER) is 54,500 pounds/QALY. In probabilistic sensitivity analyses, BCNU-W was not cost-effective in 89% of the simulations assuming a willingness to pay threshold of 30,000 pounds/QALY. In 15% of simulations, BCNU-W was dominated (i.e. did more harm than good, conferring fewer QALYs at greater cost). The cost-effectiveness acceptability curve (CEAC) suggests that it is very unlikely to be the most cost-effective option at normal levels of willingness to pay (11% probability at 30,000 pounds/QALY), only becoming likely to be the most cost-effective option at much higher levels of willingness to pay (50% probability at 55,000 pounds/QALY). Two RCTs (n = 130, n = 573) and two observational studies were included, giving evidence for 429 adult patients receiving TMZ. Currently, TMZ is licensed for use in those with newly diagnosed grade IV gliomas only. The RCTs excluded those with lower performance status and, in the larger RCT, those older than 70 years. TMZ provides a small but statistically significant median survival benefit of 2.5 months (95% CI 2.0 to 3.8), giving an HR of 0.63 (95% CI 0.52 to 0.75, p < 0.001). At 2 years, 26.5% of patients treated with TMZ were alive compared with 10.4% of those in the control arm. Median PFS is also enhanced with TMZ, giving a median 1.9 months' advantage (95% CI 1.4 to 2.7, p < 0.001). No analysis of the subgroup of patients with confirmed grade IV tumours was undertaken. Subgroup analysis of patients by O6-methylguanine-DNA methyltransferase (MGMT) activity showed a significant treatment advantage for those with reduced MGMT activity but not for those with normal activity, although this analysis was based on a selected sample of patients and the test used has proved difficult to replicate. A median gain of 6.4 (95% CI 4.4 to 9.5) more life-months is seen with TMZ among those with reduced MGMT, giving an HR of 0.51 (p < 0.007). PFS is increased by a median of 4.4 months (95% CI 1.2 to 6.3), giving an HR of 0.48 (p = 0.001). The model shows a cost per patient for being treated with surgery, radiotherapy and including adverse effects of treatment and end of life care of around 17,000 pounds per patient. TMZ in the adjuvant and concomitant phase adds an additional cost of around 7800 pounds. Across the modelled cohort of 1000 patients, use of TMZ costs an additional 7.8 million pounds and confers an additional 217 QALYs. For the average patient this is 7800 pounds for an additional 0.217 QALYs (11 quality-adjusted life-weeks). The base-case ICER is 36,000 pounds/QALY. Probabilistic sensitivity analyses shows that TMZ was not cost-effective in 77% of the simulations. The CEAC suggests that there is a 23% chance that TMZ is the most cost-effective option at a willingness to pay level of 30,000 pounds/QALY, rising to be more cost-effective than no TMZ at slightly higher levels (50% probability at 35,000 pounds/QALY). BCNU-W has not been proven to confer a significant advantage in survival for patients with grade III tumours when treated with the drug, compared with placebo. There does not appear to be a survival advantage for patients with grade IV tumours. No increase in PFS has been shown. Limited evidence suggests a small but significant advantage in both overall survival and PFS with TMZ among a mixed population with grade IV and grade III (7-8%) tumours. However, it remains unclear whether this is true in grade IV tumours alone. On the basis of best available evidence, the authors consider that neither BCNU-W nor TMZ is likely to be considered cost-effective by NHS decision-makers. However, data for the model were drawn from limited evidence of variable quality. Tumour type is clearly important in assessing patient prognosis with different treatments. Grade IV tumours are commonest and appear to have least chance of response. There were too few grade III tumours included to carry out a formal assessment, but they appear to respond better and drive results for both drugs. Future use of genetic and biomarkers may help identify subtypes which will respond, but current licensing indications do not specify these. Further research is suggested into the effectiveness of these drugs, and also into areas such as genetic markers, chemotherapy regimens, patient and carer quality of life, and patient views on survival advantages vs treatment disadvantages.

Interactions of ozone and antineoplastic drugs on rat lung fibroblasts and Walker rat carcinoma cells

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

Wenzel, D.G.; Morgan, D.L.

Cultured rat lung fibroblasts (F-cells) and Walker rat carcinoma cells (WRC-cells) labeled with /sup 51/Cr were exposed to the following antitumor drugs alone or with O/sub 3/: carmustine (BCNU), doxorubicin (Dox), cisplatin (CPt), mitomycin C (Mit C) or vitamin K/sub 3/ (Vit K). Release of /sup 51/Cr (cell injury) was greater for F-cells than WRC-cells with any single treatment. Pretreatment with any drug (400 microM), except for Vit K with WRC-cells, did not significantly increase O/sub 3/-induced loss of /sup 51/Cr. Co-exposure of F-cells to drugs and O/sub 3/ resulted in a marked potentiation of O/sub 3/-induced injury with Vitmore » K, and an inhibition with Dox.« less

[Chemotherapy in combination with laser coagulation or interstitial hyperthermia--effective combined therapy for disseminated skin melanoma].

PubMed

Akimov, M A; Gel'fond, M L; Gershanovich, M L; Barchuk, A S

2003-01-01

Thirty-eight patients with disseminated skin melanoma received chemotherapy in conjunction with laser coagulation or interstitial hyperthermia of intra- or subcutaneous metastases. Use of combination therapy was followed by a rise to 37% in total response and 16%--complete regression, respectively. Most effectiveness was attained when the dacarbazine + cisplatin + BCNU + tamoxifen regime was employed. In this group of 16 patients (46%), total response was 56% and, what is most significant, 31% in complete regression. In all cases of apparent response, polychemotherapy was administered both before and after laser coagulation or interstitial hyperthermia.

Levodopa in Treatment of Decompression Sickness and of Air Embolism Induced Paraplegia in Rats.

DTIC Science & Technology

1981-08-28

nitrosoureas (BCNU, CCNU) made additional progress in the treatment of brain tumors. A lipid soluble agent , 1,3-bis (2-Chloroethyl)-l- Nitrosourea (BCNU...mechanisms of levodopa and some other agents in the prevention and in the recovery of rats from decompression sickness. For better clarity the...brain occurring in decompression sickness. B. Decompression Sickness Studies. We have shown that gelatin, an agent that protects platelets during freezing

Synthesis and antitumor activity evaluation of a novel combi-nitrosourea prodrug: Designed to release a DNA cross-linking agent and an inhibitor of O(6)-alkylguanine-DNA alkyltransferase.

PubMed

Sun, Guohui; Zhang, Na; Zhao, Lijiao; Fan, Tengjiao; Zhang, Shufen; Zhong, Rugang

2016-05-01

The drug resistance of CENUs induced by O(6)-alkylguanine-DNA alkyltransferase (AGT), which repairs the O(6)-alkylated guanine and subsequently inhibits the formation of dG-dC cross-links, hinders the application of CENU chemotherapies. Therefore, the discovery of CENU analogs with AGT inhibiting activity is a promising approach leading to novel CENU chemotherapies with high therapeutic index. In this study, a new combi-nitrosourea prodrug 3-(3-(((2-amino-9H-purin-6-yl)oxy)methyl)benzyl)-1-(2-chloroethyl)-1-nitrosourea (6), designed to release a DNA cross-linking agent and an inhibitor of AGT, was synthesized and evaluated for its antitumor activity and ability to induce DNA interstrand cross-links (ICLs). The results indicated that 6 exhibited higher cytotoxicity against mer(+) glioma cells compared with ACNU, BCNU, and their respective combinations with O(6)-benzylguanine (O(6)-BG). Quantifications of dG-dC cross-links induced by 6 were performed using HPLC-ESI-MS/MS. Higher levels of dG-dC cross-link were observed in 6-treated human glioma SF763 cells (mer(+)), whereas lower levels of dG-dC cross-link were observed in 6-treated calf thymus DNA, when compared with the groups treated with BCNU and ACNU. The results suggested that the superiority of 6 might result from the AGT inhibitory moiety, which specifically functions in cells with AGT activity. Molecular docking studies indicated that five hydrogen bonds were formed between the O(6)-BG analogs released from 6 and the five residues in the active pocket of AGT, which provided a reasonable explanation for the higher AGT-inhibitory activity of 6 than O(6)-BG. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phase II study of second-line therapy with DTIC, BCNU, cisplatin and tamoxifen (Dartmouth regimen) chemotherapy in patients with malignant melanoma previously treated with dacarbazine.

PubMed

Propper, D J; Braybrooke, J P; Levitt, N C; O'Byrne, K; Christodoulos, K; Han, C; Talbot, D C; Ganesan, T S; Harris, A L

2000-06-01

This study assessed response rates to combination dacarbazine (DTIC), BCNU (carmustine), cisplatin and tamoxifen (DBPT) chemotherapy in patients with progressive metastatic melanoma previously treated with DTIC, as an evaluation of DBPT as a second-line regimen, and as an indirect comparison of DBPT with DTIC. Thirty-five consecutive patients received DBPT. The patients were divided into two groups. Group 1 comprised 17 patients with progressive disease (PD) on DTIC + tamoxifen therapy who were switched directly to DBPT. Group 2 comprised 18 patients not immediately switched to DBPT and included patients who had either a partial response (PR; one patient) or developed stable disease (SD; four patients) with DTIC, or received adjuvant DTIC (nine patients). All except four patients had received tamoxifen at the time of initial DTIC treatment. Median times since stopping DTIC were 22 days (range 20-41) and 285 days (range 50-1,240) in Groups 1 and 2 respectively. In Group 1, one patient developed SD for 5 months and the remainder had PD. In Group 2, there were two PRs, four patients with SD (4, 5, 6, and 6 months), and 11 with PD. These results indicate that the DBPT regimen is not of value in melanoma primarily refractory to DTIC. There were responses in patients not directly switched from DTIC to DBPT, suggesting combination therapy may be of value in a small subgroup of melanoma patients.

Inhibition of cell signaling by the combi-nitrosourea FD137 in the androgen independent DU145 prostate cancer cell line.

PubMed

Qiu, Qiyu; Dudouit, Fabienne; Banerjee, Ranjita; McNamee, James P; Jean-Claude, Bertrand J

2004-04-01

FD137, a nitrosourea appended to a quinazoline ring, was designed to simultaneously block epidermal growth factor receptor (EGFR)-mediated signaling and damage genomic DNA in refractory EGF-dependent prostate tumors. The mixed inhibition of cell signaling and DNA damage by FD137 were determined by Western blotting, RT-PCR, flow cytometry, sulforhodamine B (SRB), and comet assay. FD137 and its metabolite FD110 induced a dose-dependent increase in inhibition of EGF-stimulated EGFR autophosphorylation and this translated into blockade of c-fos gene expression in DU145 cells. FD137 induced significant levels of DNA damage and showed 150-fold greater anti-proliferative activity than BCNU, a classical nitrosourea. In contrast to BCNU, complete inhibition of EGF-induced cell transition to S-phase was observed at concentrations of FD137 as low as 3 microM. FD137 could not only damage DNA, but also significantly block downstream EGFR-mediated signaling. The superior activity of FD137 may be imputable to the combined effect of its mixed EGFR/DNA targeting properties. This novel strategy may well represent a new approach to target nitrosoureas to EGFR-overexpressing carcinomas of the prostate. Copyright 2004 Wiley-Liss, Inc.

Isocitrate dehydrogenase 1 mutant R132H sensitizes glioma cells to BCNU-induced oxidative stress and cell death.

PubMed

Mohrenz, Isabelle Vanessa; Antonietti, Patrick; Pusch, Stefan; Capper, David; Balss, Jörg; Voigt, Sophia; Weissert, Susanne; Mukrowsky, Alicia; Frank, Jan; Senft, Christian; Seifert, Volker; von Deimling, Andreas; Kögel, Donat

2013-11-01

Isocitrate dehydrogenase 1 (IDH1) decarboxylates isocitrate to α-ketoglutarate (α-KG) leading to generation of NADPH, which is required to regenerate reduced glutathione (GSH), the major cellular ROS scavenger. Mutation of R132 of IDH1 abrogates generation of α-KG and leads to conversion of α-KG to 2-hydroxyglutarate. We hypothesized that glioma cells expressing mutant IDH1 have a diminished antioxidative capacity and therefore may encounter an ensuing loss of cytoprotection under conditions of oxidative stress. Our study was performed with LN229 cells stably overexpressing IDH1 R132H and wild type IDH1 or with a lentiviral IDH1 knockdown. Quantification of GSH under basal conditions and following treatment with the glutathione reductase inhibitor BCNU revealed significantly lower GSH levels in IDH1 R132H expressing cells and IDH1 KD cells compared to their respective controls. FACS analysis of cell death and ROS production also demonstrated an increased sensitivity of IDH1-R132H-expressing cells and IDH1 KD cells to BCNU, but not to temozolomide. The sensitivity of IDH1-R132H-expressing cells and IDH1 KD cells to ROS induction and cell death was further enhanced with the transaminase inhibitor aminooxyacetic acid and under glutamine free conditions, indicating that these cells were more addicted to glutaminolysis. Increased sensitivity to BCNU-induced ROS production and cell death was confirmed in HEK293 cells inducibly expressing the IDH1 mutants R132H, R132C and R132L. Based on these findings we propose that in addition to its established pro-tumorigenic effects, mutant IDH1 may also limit the resistance of gliomas to specific death stimuli, therefore opening new perspectives for therapy.

Phase II study of second-line therapy with DTIC, BCNU, cisplatin and tamoxifen (Dartmouth regimen) chemotherapy in patients with malignant melanoma previously treated with dacarbazine

PubMed Central

Propper, D J; Braybrooke, J P; Levitt, N C; O'Byrne, K; Christodoulos, K; Han, C; Talbot, D C; Ganesan, T S; Harris, A L

2000-01-01

This study assessed response rates to combination dacarbazine (DTIC), BCNU (carmustine), cisplatin and tamoxifen (DBPT) chemotherapy in patients with progressive metastatic melanoma previously treated with DTIC, as an evaluation of DBPT as a second-line regimen, and as an indirect comparison of DBPT with DTIC. Thirty-five consecutive patients received DBPT. The patients were divided into two groups. Group 1 comprised 17 patients with progressive disease (PD) on DTIC + tamoxifen therapy who were switched directly to DBPT. Group 2 comprised 18 patients not immediately switched to DBPT and included patients who had either a partial response (PR; one patient) or developed stable disease (SD; four patients) with DTIC, or received adjuvant DTIC (nine patients). All except four patients had received tamoxifen at the time of initial DTIC treatment. Median times since stopping DTIC were 22 days (range 20–41) and 285 days (range 50–1240) in Groups 1 and 2 respectively. In Group 1, one patient developed SD for 5 months and the remainder had PD. In Group 2, there were two PRs, four patients with SD (4, 5, 6, and 6 months), and 11 with PD. These results indicate that the DBPT regimen is not of value in melanoma primarily refractory to DTIC. There were responses in patients not directly switched from DTIC to DBPT, suggesting combination therapy may be of value in a small subgroup of melanoma patients. © 2000 Cancer Research Campaign PMID:10839287

Multimodality therapy for medulloblastoma. [Efficacy and complications

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

Thomas, P.R.M.; Duffner, P.K.; Cohen, M.E.

1980-02-15

Eight patients with recurrent medulloblastoma were treated with a chemotherapy regimen consisting of vincristine, BCNU, dexamethasone and intrathecal and intermediate dose intravenous methotrexate (500 mg/m/sup 2/). Five also received local low dose radiotherapy (RT). All 8 patients responded to treatment; 6 completely and 2 partially. These latter 2 were in their second and third recurrences. Three remain in remission. The median duration of response was 18.8 months, and median time from start of chemotherapy to death was 32 months using the Kaplan-Meier technique. In addition, 9 other patients with newly diagnosed medulloblastoma were treated with craniospinal radiation and the samemore » adjuvant chemotherapy as above. The first 5 patients also received intraventricular methotrexate and/or intravenous BCNU during radiotherapy. The toxicity in the 5 patients was very severe. There were three toxic deaths, one death from cancer; one patient survives disease-free, but he is demented. With the discontinuance of intraventricular methotrexate and the postponement of myelosuppressive chemotherapy until after the completion of radiotherapy, the regimen has been well tolerated. All 4 patients treated this way remain alive, well, and disease-free at intervals up to 36 months. We conclude that recurrent medulloblastomas are sensitive to multiagent chemotherapy and that prolonged remissions may occur. With primary adjuvant chemotherapy, extreme caution with myelosuppressive drugs must be exercised during the period of craniospinal radiotherapy. We also do not recommend the use of intraventricular methotrexate. When these two criteria were followed, the preliminary results with adjuvant chemotherapy appear encouraging.« less

Evaluation of dimethoxydop-NU as a novel anti-tumor agent.

PubMed

Mukherjee, A; Dutta, S; Sanyal, U

2007-12-01

Dimethoxydop-NU, 1-[2-{3-(2-Chloroethyl)-3-nitrosoureido}ethyl]-3,4-dimethoxy-benzene (Compound 1), was synthesized from 3,4-dimethoxy-phenethylamine as a novel anti-tumor agent based on the structures of the clinical drug CCNU and dopamine, an important endogenous biological amine having anti-angiogenesis property. In vitro screening in two human tumor cell lines, namely promyelocytic leukemia HL-60 and histiocytic lymphoma U-937, revealed its cytotoxicity greater than that of hydroxyurea and comparable to BCNU used as standards. Its in vivo anti-tumoral potency was assessed in the murine ascites tumors Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times of drug treated (T) over untreated control (C) mice. Results revealed significant tumor regression effects in these tumors. The survival time of treated mice was markedly increased by combination of the compound 1 with dopamine hydrochloride. Its toxicity was assessed in vivo in normal and EAC bearing mice by measuring drug-induced changes in hematological parameters, femoral bone marrow and splenic cellularities as well as biochemical parameters sequentially on days 9, 14 and 19 following drug treatment at the optimum dose of 30 mg/kg from day 1 to 7. Results indicated that initial suppression in the femoral bone marrow cellularity seen on day 9 reached normalcy by day 19. Other parameters were within normal limit. Histopathological studies of liver revealed mild hepatotoxicity on day 9 in treated groups that substantially recovered on day 19. Similar studies with heart and kidney revealed no cardio toxicity or nephrotoxicity. Compound 1 comparable to standards inhibited the synthesis of DNA and RNA in S-180 tumor cells.

Retrospective evaluation of the MEAM regimen as a conditioning regimen before autologous peripheral blood stem cell transplantation for lymphoma in two centers with different dosing schedules of melphalan.

PubMed

Sugimoto, Miyuki; Ito, Shoko; Mashima, Kiyomi; Umino, Kento; Minakata, Daisuke; Nakano, Hirofumi; Yamasaki, Ryoko; Kawasaki, Yasufumi; Ashizawa, Masahiro; Yamamoto, Chihiro; Fujiwara, Shin-Ichiro; Okazuka, Kiyoshi; Hatano, Kaoru; Sato, Kazuya; Oh, Iekuni; Ohmine, Ken; Suzuki, Takahiro; Muroi, Kazuo; Kako, Shinichi; Kanda, Yoshinobu

2016-09-01

The BEAM regimen consisting of carmustine (BCNU), etoposide, cytarabine, and melphalan (MEL) is widely used before autologous hematopoietic stem cell transplantation (auto-HSCT) for lymphoma. However, intravenous BCNU is not available in Japan, and therefore, ranimustine (MCNU) has been used instead of BCNU (the MEAM regimen). We retrospectively analyzed the outcome of 79 adult patients who underwent auto-HSCT for lymphoma using this regimen in two centers, with 1- and 2-day dosing of MEL, respectively. Three-year overall survival (OS) and progression-free survival (PFS) probabilities were 77.3 and 56.5 % in the entire population and 71.7 and 58.0 % in patients with diffuse large B cell lymphoma. These outcomes were at least equivalent to those with the BEAM regimen. There was no regimen-related pulmonary toxicity. In a multivariate analysis, older age was the only factor that was significantly associated with for OS. In a comparison of the two MEL dosing schedules, while there was no significant differences in either OS or PFS, diarrhea was observed more frequently with 1-day dosing of MEL. In conclusion, the MEAM regimen appeared to be a promising conditioning regimen in auto-HSCT for lymphoma. A large prospective study is warranted to confirm the current findings.

Fluorescence resonance energy transfer between ZnSe ZnS quantum dots and bovine serum albumin in bioaffinity assays of anticancer drugs

NASA Astrophysics Data System (ADS)

Shu, Chang; Ding, Li; Zhong, Wenying

2014-10-01

In the current work, using ZnSe ZnS quantum dots (QDs) as representative nanoparticles, the affinities of seven anticancer drugs for bovine serum albumin (BSA) were studied using fluorescence resonance energy transfer (FRET). The FRET efficiency of BSA-QD conjugates can reach as high as 24.87% by electrostatic interaction. The higher binding constant (3.63 × 107 L mol-1) and number of binding sites (1.75) between ZnSe ZnS QDs and BSA demonstrated that the QDs could easily associate to plasma proteins and enhance the transport efficacy of drugs. The magnitude of binding constants (103-106 L mol-1), in the presence of QDs, was between drugs-BSA and drugs-QDs in agreement with common affinities of drugs for serum albumins (104-106 L mol-1) in vivo. ZnSe ZnS QDs significantly increased the affinities for BSA of Vorinostat (SAHA), Docetaxel (DOC), Carmustine (BCNU), Doxorubicin (Dox) and 10-Hydroxycamptothecin (HCPT). However, they slightly reduced the affinities of Vincristine (VCR) and Methotrexate (MTX) for BSA. The recent work will not only provide useful information for appropriately understanding the binding affinity and binding mechanism at the molecular level, but also illustrate the ZnSe ZnS QDs are perfect candidates for nanoscal drug delivery system (DDS).

In vitro cytotoxicity and differential cellular sensitivity of derivatives of diamino acids. II. N1-methyl, N1-allyl, N1-(2-chloroethyl) and N1-propargyl nitrosoureas.

PubMed

Dulude, H; Salvador, R; Gallant, G

1995-01-01

The in vitro cytotoxicity and differential cellular sensitivity of a series of new N1-methyl, N1-allyl, N1-2-chloroethyl and N1-propargyl nitrosourea derivatives of diamino acids were determined in the National Cancer Institute's primary antitumor drug screen. The compounds tested showed an in vitro anticancer activity similar to commercialized nitrosoureas such as CCNU, BCNU, MeCCNU, chlorozotocin, streptozotocin and PCNU. The alkylating moiety of the nitrosoureas seems to play a role in the general selectivity of our compounds. The N1-methyl and N1-2-chloroethyl nitrosourea derivatives are more selective for central nervous system cell lines, the N1-allyl nitrosourea derivatives are more selective for lung cancer cell lines and the N1-propargyl nitrosoureas are more selective for leukemia cell lines.

Cytotoxic and apoptotic effects of bortezomib and gefitinib compared to alkylating agents on human glioblastoma cells.

PubMed

Pédeboscq, Stéphane; L'Azou, Béatrice; Passagne, Isabelle; De Giorgi, Francesca; Ichas, François; Pometan, Jean-Paul; Cambar, Jean

2008-01-01

Glioblastoma is a malignant astrocytic tumor with a median survival of about 12 months for which new therapeutic strategies are required. We therefore examined the cytotoxicity of anticancer drugs with different mechanisms of action on two human glioblastoma cell lines expressing various levels of EGFR (epidermal growth factor receptor). Apoptosis induced by these anticancer agents was evaluated by flow cytometry. The cytotoxicity of alkylating drugs followed a dose-effect curve and cytotoxicity index values were lower with carboplatin than with BCNU and temozolomide. Anti-EGFR gefitinib (10 microM) cytotoxicity on DBTRG.05-MG expressing high levels of EGFR was significantly higher than on U87-MG expressing low levels of EGFR. Carboplatin and temozolomide cytotoxicity was potentiated with the addition of gefitinib on DBTRG.05-MG. Among the anticancer agents tested, the proteasome inhibitor bortezomib was the most cytotoxic with very low IC50 on the two cell lines. Moreover, all anticancer drugs tested induced apoptosis in a concentration-dependent manner. Bortezomib proved to be a more potent inductor of apoptosis than gefitinib and alkylating agents. These results show the efficacy of bortezomib and of the association between conventional chemotherapy and gefitinib on glioblastoma cells and therefore suggest the interest of these molecules in the treatment of glioblastoma.

In vivo observation of intracellular oximetry in perfluorocarbon-labeled glioma cells and chemotherapeutic response in the CNS using fluorine-19 MRI

PubMed Central

Kadayakkara, Deepak K.K.; Janjic, Jelena M.; Pusateri, Lisa B.; Young, Won-Bin; Ahrens, Eric T.

2010-01-01

Preclinical development of therapeutic agents against cancer could greatly benefit from noninvasive markers of tumor killing. Potentially, the intracellular partial pressure of oxygen (pO2) can be used as an early marker of anti-tumor efficacy. Here, the feasibility of measuring intracellular pO2 of CNS glioma cells in vivo using 19F magnetic resonance techniques is examined. Rat 9L glioma cells were labeled with perfluoro-15-crown-5-ether (PCE) ex vivo and then implanted into the rat striatum. 19F MRI was used to visualize tumor location in vivo. The mean 19F T1 of the implanted cells was measured using localized, single-voxel spectroscopy. The intracellular pO2 in tumor cells was determined from an in vitro calibration curve. The basal pO2 of 9L cells (day 3) was determined to be 45.3±5 mm Hg (n=6). Rats were then treated with a 1× LD10 dose of bischloroethylnitrosourea (BCNU) intravenously, and changes in intracellular pO2 were monitored. The pO2 increased significantly (p=0.042, paired T-test) to 141.8±3 mm Hg within 18 hours after BCNU treatment (day 4) and remained elevated (165±24 mm Hg) for at least 72 hours (day 6). Intracellular localization of the PCE emulsion in 9L cells before and after BCNU treatment was confirmed by histological examination and fluorescence microscopy. Overall, non-invasive 19F magnetic resonance techniques may provide a valuable preclinical tool for monitoring therapeutic response against CNS or other deep-seated tumors. PMID:20860007

Nitric oxide donors attenuate clongenic potential in rat C6 glioma cells treated with alkylating chemotherapeutic agents.

PubMed

Yang, Jir-Jei; Yin, Jiu-Haw; Yang, Ding-I

2007-05-11

1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU) kills tumor cells via multiple actions including alkylation and carbamoylation. Previously, we have reported that formation of S-nitrosoglutathione (GSNO) in glioma cells overexpressing inducible nitric oxide synthase (iNOS) contributed to nitric oxide (NO)-dependent carbamoylating chemoresistance against BCNU. To further characterize the effects of NO on alkylating cytotoxicity, colony formation assay was applied to evaluate the effects of various NO donors on rat C6 glioma cells challenged with alkylating agents. We demonstrate that NO donors including GSNO, diethylamine NONOate (DEA/NO), and sodium nitroprusside (SNP) substantially reduced the extent of colony formation in glioma cells treated with alkylating agents, namely methyl methanesulfonate (MMS), N-methyl-N-nitrosourea (MNU), and N-ethyl-N-nitrosourea (ENU). Without alkylating agents these NO-releasing agents alone had no effects on clongenic potential of rat C6 glioma cells. Among these three NO donors used, the effectiveness in potentiating alkylating cytotoxicity is in the order of "GSNO>DEA/NO>SNP" when applied at the same dosages. GSNO also exerted similar synergistic actions reducing the extents of colony formation when co-administrated with 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-hydrazine (compound #1), another alkylating agent that mimics the chloroethylating action of BCNU. Together with our previous findings, we propose that NO donors may be used as adjunct chemotherapy with alkylating agents for such malignant brain tumors as glioblastoma multiforme (GBM). In contrast, production of NO as a result of iNOS induction, such as that occurring after surgical resection of brain tumors, may compromise the efficacy of carbamoylating chemotherapy.

Concentration rather than dose defines the local brain toxicity of agents that are effectively distributed by convection-enhanced delivery.

PubMed

Zhang, Rong; Saito, Ryuta; Mano, Yui; Kanamori, Masayuki; Sonoda, Yukihiko; Kumabe, Toshihiro; Tominaga, Teiji

2014-01-30

Convection-enhanced delivery (CED) has been developed as a potentially effective drug-delivery strategy into the central nervous system. In contrast to systemic intravenous administration, local delivery achieves high concentration and prolonged retention in the local tissue, with increased chance of local toxicity, especially with toxic agents such as chemotherapeutic agents. Therefore, the factors that affect local toxicity should be extensively studied. With the assumption that concentration-oriented evaluation of toxicity is important for local CED, we evaluated the appearance of local toxicity among different agents after delivery with CED and studied if it is dose dependent or concentration dependent. Local toxicity profile of chemotherapeutic agents delivered via CED indicates BCNU was dose-dependent, whereas that of ACNU was concentration-dependent. On the other hand, local toxicity for doxorubicin, which is not distributed effectively by CED, was dose-dependent. Local toxicity for PLD, which is extensively distributed by CED, was concentration-dependent. Traditional evaluation of drug induced toxicity was dose-oriented. This is true for systemic intravascular delivery. However, with local CED, toxicity of several drugs exacerbated in concentration-dependent manner. From our study, local toxicity of drugs that are likely to distribute effectively tended to be concentration-dependent. Concentration rather than dose may be more important for the toxicity of agents that are effectively distributed by CED. Concentration-oriented evaluation of toxicity is more important for CED. Copyright © 2013 Elsevier B.V. All rights reserved.

Repeated high-dose chemotherapy followed by purged autologous bone marrow transplantation as consolidation therapy in metastatic neuroblastoma.

PubMed

Hartmann, O; Benhamou, E; Beaujean, F; Kalifa, C; Lejars, O; Patte, C; Behard, C; Flamant, F; Thyss, A; Deville, A

1987-08-01

Among 62 children over 1 year of age at diagnosis, who were treated for stage IV neuroblastoma, 33 entered complete remission (CR) or good partial remission (GPR) after conventional therapy and received high-dose chemotherapy (HDC) with in vitro purged autologous bone marrow transplantation (ABMT) as consolidation therapy. The HDC was a combination of carmustine (BCNU), teniposide (VM-26), and melphalan. Thirty-three patients received one course of this regimen, and 18 received two courses. At present, 16 of the 33 grafted patients are alive in continuous CR, with a median follow-up of 28 months. Toxicity of this regimen was tolerable, principally marked by bone marrow depression and gastrointestinal (GI) tract complications. Four complication-related deaths were observed. Relapse post-ABMT occurred most often in the bone marrow. Under this treatment, actuarial disease-free survival is improved compared with that observed under conventional therapy.

Lecture: fotemustine in brain tumors.

PubMed

Silvani, A; Gaviani, P; Lamperti, E; Botturi, A; Ferrari, D; Simonetti, G; Salmaggi, A

2011-11-01

Fotemustine (FTMS) is a third-generation nitrosourea, in preclinical studies, FTMS compared favorably with carmustine (BCNU) and lomustine (CCNU) against several human tumor cell lines. In conventional schedule, FTMS is administered at a dose of 100 mg/sqm/week for three consecutive weeks as induction (I) treatment, followed by 100 mg/sqm every three weeks, after a 5-week rest, as maintenance (M). Several Italian groups reported the results using FTMS in malignant glioma patients recurring after temozolomide standard treatment. In these papers, the 6-progression free survival are ranging from 20 to 52%. With the schedule (I + M) myelosuppression is observed in more than 30% of patients, and thrombocytopenia and leukopenia are more frequent and significant in Temozolomide pretreated patients. On the bases of the hematological toxicities several authors experimented new schedules of FTMS administrated at low doses. Recently, some authors reported the interesting results of a multicenter study on recurrent glioblastoma multiforme patients combining FTMS with new antiangiogentic agent bevacizumab.

Emergence of nitrosourea resistant sublines of Lewis lung tumour following MeCCNU treatment in vivo.

PubMed Central

Stephens, T. C.; Adams, K.; Peacock, J. H.

1986-01-01

Several different drug retreatment protocols were employed to examine the emergence of resistance to MeCCNU in Lewis lung tumours. Previous studies suggested that although the majority of cells in untreated Lewis lung tumours were sensitive to MeCCNU, there was a very small proportion of resistant cells (approximately 0.001%) that limited "tumour cure' with that drug. If such cells were inherently drug resistant then it should be possible to derive highly resistant tumours by repeated drug treatment. In the first experiment tumours were treated with a single high dose of MeCCNU (35 or 40 mgkg-1) and on regrowth, transplanted into fresh mice and tested for drug sensitivity. Using both excision cell survival and growth delay endpoints, only approximately 25% of tumours were significantly resistant to the test dose, suggesting that many tumours resist the effects of the drug for reasons other than the presence of inherently drug resistant cells. One of the tumours (R4), that regrew after the initial treatment and appeared to be resistant to the test treatment, was retreated with a further 30 mgkg-1 MeCCNU and became more resistant. This line, designated R4/1, was cross-resistant to the other nitrosoureas, BCNU and CCNU, but not to cyclophosphamide, melphalan, cis-platinum or ionising radiation. The effect of treatment dose on the kinetics of MeCCNU resistance development was also studied in a retreatment regimen where the tumours were allowed to regrow and then transplanted into fresh hosts for the next treatment. Resistance developed more quickly at an intermediate dose of 15 mgkg-1 than at 7.5 mgkg-1 where the selective pressure was lower, or at 30 mgkg-1 where there was probably extinction of partially resistant cells. Resistance to MeCCNU developed even more quickly when tumours were retreated several times in the same host, although in a similar experiment with cyclophosphamide no resistance occurred. PMID:3954945

The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for malignant glioma

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

Tsao, May N.; Mehta, Minesh P.; Whelan, Timothy J.

2005-09-01

Purpose: To systematically review the evidence for the use of stereotactic radiosurgery or stereotactic fractionated radiation therapy in adult patients with malignant glioma. Methods: Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncologymore » (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. Results: For patients with newly diagnosed malignant glioma, radiosurgery as boost therapy with conventional external beam radiation was examined in one randomized trial, five prospective cohort studies, and seven retrospective series. There is Level I evidence that the use of radiosurgery boost followed by external beam radiotherapy and carmustine (BCNU) does not confer benefit with respect to overall survival, quality of life, or patterns of failure as compared with external beam radiotherapy and BCNU. There is Level I-III evidence of toxicity associated with radiosurgery boost as compared with external beam radiotherapy alone. The results of the prospective and retrospective studies may be influenced by selection bias. Radiosurgery used as salvage for recurrent or progressive malignant glioma after conventional external beam radiotherapy failure was reported in zero randomized trials, three prospective cohort studies, and five retrospective series. The available data are sparse and insufficient to make absolute recommendations. Stereotactic fractionated radiation therapy has been reported as boost therapy with external beam radiotherapy for patients with newly diagnosed malignant glioma in only three prospective studies. As primary therapy alone without conventional external beam radiotherapy for newly diagnosed malignant glioma patients, stereotactic fractionated radiation therapy has been reported in only one prospective study. There were only three prospective series and two retrospective studies reported for patients with recurrent or progressive malignant glioma. Conclusions: For patients with malignant glioma, there is Level I-III evidence that the use of radiosurgery boost followed by external beam radiotherapy and BCNU does not confer benefit in terms of overall survival, local brain control, or quality of life as compared with external beam radiotherapy and BCNU. The use of radiosurgery boost is associated with increased toxicity. For patients with malignant glioma, there is insufficient evidence regarding the benefits/harms of using radiosurgery at the time progression or recurrence. There is also insufficient evidence regarding the benefits/harms in the use of stereotactic fractionated radiation therapy for patients with newly diagnosed or progressive/recurrent malignant glioma.« less

PAM-OBG: A monoamine oxidase B specific prodrug that inhibits MGMT and generates DNA interstrand crosslinks, potentiating temozolomide and chemoradiation therapy in intracranial glioblastoma

PubMed Central

Sharpe, Martyn A.; Raghavan, Sudhir; Baskin, David S.

2018-01-01

Via extensive analyses of genetic databases, we have characterized the DNA-repair capacity of glioblastoma with respect to patient survival. In addition to elevation of O6-methylguanine DNA methyltransferase (MGMT), down-regulation of three DNA repair pathways; canonical mismatch repair (MMR), Non-Homologous End-Joining (NHEJ), and Homologous Recombination (HR) are correlated with poor patient outcome. We have designed and tested both in vitro and in vivo, a monoamine oxidase B (MAOB) specific prodrug, PAM-OBG, that is converted by glioma MAOB into the MGMT inhibitor O6-benzylguanine (O6BG) and the DNA crosslinking agent acrolein. In cultured glioma cells, we show that PAM-OBG is converted to O6BG, inhibiting MGMT and sensitizing cells to DNA alkylating agents such as BCNU, CCNU, and Temozolomide (TMZ). In addition, we demonstrate that the acrolein generated is highly toxic in glioma treated with an inhibitor of Nucleotide Excision Repair (NER). In mouse intracranial models of primary human glioma, we show that PAM-OBG increases survival of mice treated with either BCNU or CCNU by a factor of six and that in a chemoradiation model utilizing six rounds of TMZ/2Gy radiation, pre-treatment with PAM-OBG more than doubled survival time. PMID:29844863

PAM-OBG: A monoamine oxidase B specific prodrug that inhibits MGMT and generates DNA interstrand crosslinks, potentiating temozolomide and chemoradiation therapy in intracranial glioblastoma.

PubMed

Sharpe, Martyn A; Raghavan, Sudhir; Baskin, David S

2018-05-08

Via extensive analyses of genetic databases, we have characterized the DNA-repair capacity of glioblastoma with respect to patient survival. In addition to elevation of O 6 -methylguanine DNA methyltransferase (MGMT), down-regulation of three DNA repair pathways; canonical mismatch repair (MMR), Non-Homologous End-Joining (NHEJ), and Homologous Recombination (HR) are correlated with poor patient outcome. We have designed and tested both in vitro and in vivo , a monoamine oxidase B (MAOB) specific prodrug, PAM-OBG, that is converted by glioma MAOB into the MGMT inhibitor O 6 -benzylguanine (O 6 BG) and the DNA crosslinking agent acrolein. In cultured glioma cells, we show that PAM-OBG is converted to O 6 BG, inhibiting MGMT and sensitizing cells to DNA alkylating agents such as BCNU, CCNU, and Temozolomide (TMZ). In addition, we demonstrate that the acrolein generated is highly toxic in glioma treated with an inhibitor of Nucleotide Excision Repair (NER). In mouse intracranial models of primary human glioma, we show that PAM-OBG increases survival of mice treated with either BCNU or CCNU by a factor of six and that in a chemoradiation model utilizing six rounds of TMZ/2Gy radiation, pre-treatment with PAM-OBG more than doubled survival time.

Synthesis, SAR and biological evaluation of a novel series of 1-(2-chloroethyl)-1-nitroso-3-(2-(3-oxobenzoelenazol-2(3H)-yl)ethyl) urea: Organoselenium compounds for cancer therapy.

PubMed

Ye, S; Zheng, X; Hu, T; Zeng, H

2016-06-30

Thioredoxin reductase 1 (TrxR1) is an important potential anticancer drug target and closely related to both carcinogenesis and cancer progression. Ethaselen (BBSKE), a novel organoselenium compound inhibiting TrxR1 with selective antitumor effect, while its symmetrical structure results in poor solubility. Carmustine (BCNU), a DNA cross-link agent and also a deactivator of TrxR, is with high toxicity and low selectivity which limit its clinical application to some extents. Herein, a novel compound, 1-(2-chloroethyl)-1-nitroso-3-(2-(3-oxobenzoelenazol-2(3H)-yl)ethyl)urea(4a-1), which was designed through the combination of Ethaselen and Carmustine, showed good solubility, good tagetability, low toxicity and excellent antitumor activity by synergism. Using the structure of 4a-1 as a key active scaffold, a series of novel 1-(2-chloroethyl)-1-nitroso-3-(2-(3-oxobenzoelenazol-2(3H)-yl)ethyl)urea was designed, synthesized and evaluated to explore the structure-activity relationships (SARs) of these inhibitors and to improve their antitumor activities. Notably, 1-(2-chloroethyl)-3-(2-(6-fluoro-3-oxobenzoselenazol-2(3H)-yl)ethyl)-1-nitrosourea(4b-1) was found to exhibit more potent antitumor activities comparable to 4a-1 against all the four cancer cell lines, including Mia PaCa-2, PANC-1, RKO, LoVo. These results have highlighted compound 4b-1 as a new potential lead candidate for future development of novel potent broad-spectrum antitumor agents. In addition, a SAR model was established to conduct further structural modification.

Chronic hematuria and localized bladder damage following combined cyclophosphamide and local radiotherapy

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

Kende, G.; Wajsman, Z.; Thomas, P.R.M.

1979-01-01

A 13-year-old white male had Ewing sarcoma of the right pubic and ischial bones. Initial therapy consisted of 5400 rads in seven weeks to the right side of the pelvis and 14 intravenous injections of cyclophosphamide (Cytoxan, CTX) at 500 mg/m/sup 2/; BCNU and Adriamycin maintenance therapy continued for a total of two years. He has now been disease-free for five years. Three months following the completion of the right pelvic radiotherapy (RT), while on intravenous CTX, severe hematuria appeared, which subsided, but at present he has continuous microscopic hematuria, as well as periodic episodes of gross hematuria. Serial cystocopiesmore » initially revealed thickening and hemorrhagic and edematous changes on the right (irradiated) side of the bladder, and recent multiple telangiectatic patches have been demonstrated as a late healing phase. This case demonstrates the additive toxicity to the bladder of CTX and RT, illustrating that the hemorrhagic cystitis can be extremely protracted lasting five years.« less

A practical toxicity bioassay for vicine and convicine levels in faba bean (Vicia faba).

PubMed

Getachew, Fitsum; Vandenberg, Albert; Smits, Judit

2018-04-02

Faba bean (Vicia faba) vicine and convicine (V-C) aglycones (divicine and isouramil respectively) provoke an acute hemolytic anemia called favism in individuals with a glucose-6-phosphate dehydrogenase (G6PD) enzyme defect in their red blood cells. Geneticists/plant breeders are working with faba bean to decrease V-C levels to improve public acceptance of this high-protein pulse crop. Here, we present a fast and simple ex vivo in vitro bioassay for V-C toxicity testing of faba bean or faba bean food products. We have shown that 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU)-treated (i.e., sensitized) normal red blood cells, like G6PD-defective blood, displayed (i) continuous glutathione (GSH) depletion with no regeneration as incubation time and the dose of aglycones increased, (ii) progressive accumulation of denatured hemoglobin products into high molecular weight (HMW) proteins with increased aglycone dose, (iii) both band 3 membrane proteins and hemichromes, in HMW protein aggregates. We have also demonstrated that sensitized red blood cells can effectively differentiate various levels of toxicity among faba bean varieties through the two hemolysis biomarkers: GSH depletion and HMW clumping. BCNU-sensitized red blood cells provide an ideal model for favism blood, to assess and compare the toxicity of faba bean varieties and their food products. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Pre-irradiation chemotherapy for newly diagnosed high grade astrocytoma.

PubMed

Mathieu, N Tubiana; Genet, D; Labrousse, F; Bouillet, P; Denes, S Lavau; Martin, J; Labourey, J L; Venat, L; Clavere, P; Moreau, J J

2004-01-01

The purpose of this work was to determine the response rate and toxicity of a combination of Carmustine and Cisplatin administered before radiation in patients with newly diagnosed high grade astrocytoma. A good response rate has been published with this association in primary cerebral high grade tumor. This protocol was administered in a homogeneous population of 37 adult patients with measurable tumor on magnetic resonance imaging (MRI) or CT scan. After biopsy or subtotal resection, the patients received BCNU 40 mg/m2/d and CODP 40 mg/m2/d, for 3 days every 28 days for 3 cycles. Evaluation was performed before each cycle. Radiation therapy began 4 weeks after completing the chemotherapy or immediately if there was evidence of tumor progression on chemotherapy. Seven out of 37 (19%) demonstrated tumor regression with a median duration to progression of 11 months. Median survival was 6 months. Myelosuppression was the predominant but manageable toxicity. This work indicated that the first chemotherapy protocol gave poor results in a homogeneous group of patients, with bad prognosis.

Superiority of bortezomib, thalidomide, and dexamethasone (VTD) as induction pretransplantation therapy in multiple myeloma: a randomized phase 3 PETHEMA/GEM study.

PubMed

Rosiñol, Laura; Oriol, Albert; Teruel, Ana Isabel; Hernández, Dolores; López-Jiménez, Javier; de la Rubia, Javier; Granell, Miquel; Besalduch, Joan; Palomera, Luis; González, Yolanda; Etxebeste, María Asunción; Díaz-Mediavilla, Joaquín; Hernández, Miguel T; de Arriba, Felipe; Gutiérrez, Norma C; Martín-Ramos, María Luisa; Cibeira, María Teresa; Mateos, María Victoria; Martínez, Joaquín; Alegre, Adrián; Lahuerta, Juan José; San Miguel, Jesús; Bladé, Joan

2012-08-23

The Spanish Myeloma Group conducted a trial to compare bortezomib/thalidomide/dexamethasone (VTD) versus thalidomide/dexamethasone (TD) versus vincristine, BCNU, melphalan, cyclophosphamide, prednisone/vincristine, BCNU, doxorubicin, dexamethasone/bortezomib (VBMCP/VBAD/B) in patients aged 65 years or younger with multiple myeloma. The primary endpoint was complete response (CR) rate postinduction and post-autologous stem cell transplantation (ASCT). Three hundred eighty-six patients were allocated to VTD (130), TD (127), or VBMCP/VBAD/B (129). The CR rate was significantly higher with VTD than with TD (35% vs 14%, P = .001) or with VBMCP/VBAD/B (35% vs 21%, P = .01). The median progression-free survival (PFS) was significantly longer with VTD (56.2 vs 28.2 vs 35.5 months, P = .01). In an intention-to-treat analysis, the post-ASCT CR rate was higher with VTD than with TD (46% vs 24%, P = .004) or with VBMCP/VBAD/B (46% vs 38%, P = .1). Patients with high-risk cytogenetics had a shorter PFS and overall survival in the overall series and in all treatment groups. In conclusion, VTD resulted in a higher pre- and posttransplantation CR rate and in a significantly longer PFS although it was not able to overcome the poor prognosis of high-risk cytogenetics. Our results support the use of VTD as a highly effective induction regimen prior to ASCT. The study was registered with http://www.clinicaltrials.gov (NCT00461747) and Eudra CT (no. 2005-001110-41).

Successful immunotherapy with micrococcus, BCG or related polysaccharides on L1210 leukaemia after BCNU chemotherapy.

PubMed Central

Verloes, R.; Atassi, G.; Dumont, P.; Kanarek, L.

1981-01-01

The experiments aimed at evaluating the optimal parameters in the chemo-immunotherapeutic treatment of the L1210 lymphoid leukaemia grafted to [female BALB/c (H2d) X male DBA/2 (H2d)]F1 hybrid mice, hereafter referred to as CDF1 mice. In vitro irradiation of leukaemic ascites cells by X- or gamma-rays and subsequent inoculation in mice showed that optimum immunogenicity is radiation dose-dependent. Grafting mice with 10(7) leukaemic ascites cells irradiated at optimum dose (80 GyX- or gamma-rays) delays mortality of the animals when challenged later with untreated L1210 cells, but is unable to cure mice. By contrast, specific immunoprophylaxis induced by Micrococcus, complement-triggering polysaccharides or BCG and irradiated leukaemic cells was able to protect mice against grafts of 10(4) L1210 cells. The i.p. route was notably superior to the i.v. route. When mice bearing advanced L1210 tumour were treated by chemotherapy (12 mg/kg of BCNU) on Day 6.5 after grafting 10(4) L1210 cells and subsequently treated by immunotherapy, a very high percentage (up to 90%) of mice with 10(8) leukaemic cells could be cured by repeated 1mg injections of bacterium or polysaccharide, and challenge with irradiated leukaemic cells was unnecessary. Because of the high cure rate obtained, the very regular response pattern and the non-pathogenicity, the bacterium Micrococcus lysodeikticus would seem a promising new candidate for chemo-immunotherapeutic antitumour strategies. PMID:7470382

In vivo selection of hematopoietic progenitor cells and temozolomide dose intensification in rhesus macaques through lentiviral transduction with a drug resistance gene

PubMed Central

Larochelle, Andre; Choi, Uimook; Shou, Yan; Naumann, Nora; Loktionova, Natalia A.; Clevenger, Joshua R.; Krouse, Allen; Metzger, Mark; Donahue, Robert E.; Kang, Elizabeth; Stewart, Clinton; Persons, Derek; Malech, Harry L.; Dunbar, Cynthia E.; Sorrentino, Brian P.

2009-01-01

Major limitations to gene therapy using HSCs are low gene transfer efficiency and the inability of most therapeutic genes to confer a selective advantage on the gene-corrected cells. One approach to enrich for gene-modified cells in vivo is to include in the retroviral vector a drug resistance gene, such as the P140K mutant of the DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT*). We transplanted 5 rhesus macaques with CD34+ cells transduced with lentiviral vectors encoding MGMT* and a fluorescent marker, with or without homeobox B4 (HOXB4), a potent stem cell self-renewal gene. Transgene expression and common integration sites in lymphoid and myeloid lineages several months after transplantation confirmed transduction of long-term repopulating HSCs. However, all animals showed only a transient increase in gene-marked lymphoid and myeloid cells after O6-benzylguanine (BG) and temozolomide (TMZ) administration. In 1 animal, cells transduced with MGMT* lentiviral vectors were protected and expanded after multiple courses of BG/TMZ, providing a substantial increase in the maximum tolerated dose of TMZ. Additional cycles of chemotherapy using 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) resulted in similar increases in gene marking levels, but caused high levels of nonhematopoietic toxicity. Inclusion of HOXB4 in the MGMT* vectors resulted in no substantial increase in gene marking or HSC amplification after chemotherapy treatment. Our data therefore suggest that lentivirally mediated gene transfer in transplanted HSCs can provide in vivo chemoprotection of progenitor cells, although selection of long-term repopulating HSCs was not seen. PMID:19509470

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

Hang, Bo; Guliaev, Anton B.; Chenna, Ahmed

1,N{sup 6}-Ethanoadenine (EA) is an exocyclic adduct formed from DNA reaction with the antitumor agent, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). To understand the role of this adduct in the mechanism of mutagenicity or carcinogenicity by BCNU, an oligonucleotide with a site-specific EA was synthesized using phosphoramidite chemistry. We now report the in vitro miscoding properties of EA in translesion DNA synthesis catalyzed by mammalian DNA polymerases (pols) {alpha}, {beta}, {eta} and {iota}. These data were also compared with those obtained for the structurally related exocyclic adduct, 1,N{sup 6}-ethenoadenine ({var_epsilon}A). Using a primer extension assay, both pols {alpha} and {beta} were primarily blocked bymore » EA or {var_epsilon}A with very minor extension. Pol {eta} a member of the Y family of polymerases, was capable of catalyzing a significant amount of bypass across both adducts. Pol {eta} incorporated all four nucleotides opposite EA and {var_epsilon}A, but with differential preferences and mainly in an error-prone manner. Human pol {iota}, a paralog of human pol {eta}, was blocked by both adducts with a very small amount of synthesis past {var_epsilon}A. It incorporated C and, to a much lesser extent, T, opposite either adduct. In addition, the presence of an A adduct, e.g. {var_epsilon}A, could affect the specificity of pol {iota} toward the template T immediately 3 feet to the adduct. In conclusion, the four polymerases assayed on templates containing an EA or {var_epsilon}A showed differential bypass capacity and nucleotide incorporation specificity, with the two adducts not completely identical in influencing these properties. Although there was a measurable extent of error-free nucleotide incorporation, all these polymerases primarily misincorporated opposite EA, indicating that the adduct, similar to {var_epsilon}A, is a miscoding lesion.« less

New insights into estrogenic regulation of O6-methylguanine DNA-methyltransferase (MGMT) in human breast cancer cells: Co-degradation of ER-α and MGMT proteins by fulvestrant or O6-benzylguanine indicates fresh avenues for therapy.

PubMed

Paranjpe, Ameya; Bailey, Nathan I; Konduri, Santhi; Bobustuc, George C; Ali-Osman, Francis; Yusuf, Mohd A; Punganuru, Surendra R; Madala, Hanumantha Rao; Basak, Debasish; Mostofa, Agm; Srivenugopal, Kalkunte S

2016-09-01

Endocrine therapy using estrogen receptor-α (ER-α) antagonists for attenuating horm2one-driven cell proliferation is a major treatment modality for breast cancers. To exploit any DNA repair deficiencies associated with endocrine therapy, we investigated the functional and physical interactions of ER-α with O 6 -methylguanine DNA methyltransferase (MGMT), a unique DNA repair protein that confers tumor resistance to various anticancer alkylating agents. The ER-α -positive breast cancer cell lines (MCF-7, T47D) and ER- negative cell lines (MDAMB-468, MDAMB-231), and established inhibitors of ER-α and MGMT, namely, ICI-182,780 (Faslodex) and O 6 -benzylguanine, respectively, were used to study MGMT- ER interactions. The MGMT gene promoter was found to harbor one full and two half estrogen-responsive elements (EREs) and two antioxidant-responsive elements (AREs). MGMT expression was upregulated by estrogen, downregulated by tamoxifen in Western blot and promoter-linked reporter assays. Similarly, both transient and stable transfections of Nrf-2 (nuclear factor-erythroid 2-related factor-2) increased the levels of MGMT protein and activity 3 to 4-fold reflecting novel regulatory nodes for this drug-resistance determinant. Of the different ER-α antagonists tested, the pure anti-estrogen fulvestrant was most potent in inhibiting the MGMT activity in a dose, time and ER-α dependent manner, similar to O 6 -benzylguanine. Interestingly, fulvestrant exposure led to a degradation of both ER-α and MGMT proteins and O 6 -benzylguanine also induced a specific loss of ER-α and MGMT proteins in MCF-7 and T47D breast cancer cells with similar kinetics. Immunoprecipitation revealed a specific association of ER-α and MGMT proteins in breast cancer cells. Furthermore, silencing of MGMT gene expression triggered a decrease in the levels of both MGMT and ER-α proteins. The involvement of proteasome in the drug-induced degradation of both proteins was also demonstrated. Fulvestrant enhanced the cytotoxicity of MGMT-targeted alkylating agents, namely, temozolomide and BCNU by 3 to 4-fold in ER-α positive cells, but not in ER-negative cells. We conclude that MGMT and ER-α proteins exist as a complex and are co-targeted for ubiquitin-conjugation and subsequent proteasomal degradation. The findings offer a clear rationale for combining alkylating agents with endocrine therapy. © 2016 the Journal of Biomedical Research. All rights reserved.

Influence of Glutathione and Glutathione S-transferases on DNA Interstrand Cross-Link Formation by 1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine, the Active Anticancer Moiety Generated by Laromustine

PubMed Central

2015-01-01

Prodrugs of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (90CE) are promising anticancer agents. The 90CE moiety is a readily latentiated, short-lived (t1/2 ∼ 30 s) chloroethylating agent that can generate high yields of oxophilic electrophiles responsible for the chloroethylation of the O-6 position of guanine in DNA. These guanine O-6 alkylations are believed to be responsible for the therapeutic effects of 90CE and its prodrugs. Thus, 90CE demonstrates high selectivity toward tumors with diminished levels of O6-alkylguanine-DNA alkyltransferase (MGMT), the resistance protein responsible for O6-alkylguanine repair. The formation of O6-(2-chloroethyl)guanine lesions ultimately leads to the generation of highly cytotoxic 1-(N3-cytosinyl),-2-(N1-guaninyl)ethane DNA interstrand cross-links via N1,O6-ethanoguanine intermediates. The anticancer activity arising from this sequence of reactions is thus identical to this component of the anticancer activity of the clinically used chloroethylnitrosoureas. Herein, we evaluate the ability of glutathione (GSH) and other low molecular weight thiols, as well as GSH coupled with various glutathione S-transferase enzymes (GSTs) to attenuate the final yields of cross-links generated by 90CE when added prior to or immediately following the initial chloroethylation step to determine the major point(s) of interaction. In contrast to studies utilizing BCNU as a chloroethylating agent by others, GSH (or GSH/GST) did not appreciably quench DNA interstrand cross-link precursors. While thiols alone offered little protection at either alkylation step, the GSH/GST couple was able to diminish the initial yields of cross-link precursors. 90CE exhibited a very different GST isoenzyme susceptibility to that reported for BCNU, this could have important implications in the relative resistance of tumor cells to these agents. The protection afforded by GSH/GST was compared to that produced by MGMT. PMID:25012050

Influence of glutathione and glutathione S-transferases on DNA interstrand cross-link formation by 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine, the active anticancer moiety generated by laromustine.

PubMed

Penketh, Philip G; Patridge, Eric; Shyam, Krishnamurthy; Baumann, Raymond P; Zhu, Rui; Ishiguro, Kimiko; Sartorelli, Alan C

2014-08-18

Prodrugs of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (90CE) are promising anticancer agents. The 90CE moiety is a readily latentiated, short-lived (t1/2 ∼ 30 s) chloroethylating agent that can generate high yields of oxophilic electrophiles responsible for the chloroethylation of the O-6 position of guanine in DNA. These guanine O-6 alkylations are believed to be responsible for the therapeutic effects of 90CE and its prodrugs. Thus, 90CE demonstrates high selectivity toward tumors with diminished levels of O(6)-alkylguanine-DNA alkyltransferase (MGMT), the resistance protein responsible for O(6)-alkylguanine repair. The formation of O(6)-(2-chloroethyl)guanine lesions ultimately leads to the generation of highly cytotoxic 1-(N(3)-cytosinyl),-2-(N(1)-guaninyl)ethane DNA interstrand cross-links via N(1),O(6)-ethanoguanine intermediates. The anticancer activity arising from this sequence of reactions is thus identical to this component of the anticancer activity of the clinically used chloroethylnitrosoureas. Herein, we evaluate the ability of glutathione (GSH) and other low molecular weight thiols, as well as GSH coupled with various glutathione S-transferase enzymes (GSTs) to attenuate the final yields of cross-links generated by 90CE when added prior to or immediately following the initial chloroethylation step to determine the major point(s) of interaction. In contrast to studies utilizing BCNU as a chloroethylating agent by others, GSH (or GSH/GST) did not appreciably quench DNA interstrand cross-link precursors. While thiols alone offered little protection at either alkylation step, the GSH/GST couple was able to diminish the initial yields of cross-link precursors. 90CE exhibited a very different GST isoenzyme susceptibility to that reported for BCNU, this could have important implications in the relative resistance of tumor cells to these agents. The protection afforded by GSH/GST was compared to that produced by MGMT.

A Comparison of the Conditioning Regimens BEAM and FEAM for Autologous Hematopoietic Stem Cell Transplantation in Lymphoma: an Observational Study on Patients From Fondazione Italiana Linfomi (Fil).

PubMed

Olivieri, Jacopo; Mosna, Federico; Pelosini, Matteo; Fama, Angelo; Rattotti, Sara; Giannoccaro, Margherita; Carli, Giuseppe; Tisi, Maria Chiara; Ferrero, Simone; Sgherza, Nicola; Mazzone, Anna Maria; Marino, Dario; Calimeri, Teresa; Loseto, Giacomo; Saraceni, Francesco; Tomei, Gabriella; Sica, Simona; Perali, Giulia; Codeluppi, Katia; Billio, Atto; Olivieri, Attilio; Orciuolo, Enrico; Matera, Rossella; Stefani, Piero Maria; Borghero, Carlo; Ghione, Paola; Cascavilla, Nicola; Lanza, Francesco; Chiusolo, Patrizia; Finotto, Silvia; Federici, Irene; Gherlinzoni, Filippo; Centurioni, Riccardo; Fanin, Renato; Zaja, Francesco

2018-05-29

Carmustine (BCNU)-Etoposide-Citarabine-Melphalan (BEAM) chemotherapy is the standard conditioning regimen for autologous stem cell transplantation (ASCT) in lymphomas. Owing to BCNU shortages, many centers switched to Fotemustine-substituted BEAM (FEAM), lacking proof of equivalence. We conducted a retrospective cohort study in 18 Italian centers to compare safety and efficacy of BEAM and FEAM regimens for ASCT in lymphomas performed from 2008 to 2015. We enrolled 1038 patients (BEAM n=607, FEAM n=431), of which 27% had Hodgkin's lymphoma (HL), 14% indolent Non-Hodgkin's lymphoma (iNHL) and 59% aggressive NHL (aNHL). Baseline characteristics including age, sex, stage, B-symptoms, extranodal involvement, previous treatments, response before ASCT, overall conditioning intensity, were well balanced between BEAM and FEAM; notable exceptions were: ASCT year (median: BEAM=2011 vs FEAM=2013, p<0.001), Sorror score (≥3: BEAM=15% vs FEAM=10%, p=0.017), radiotherapy use (BEAM=18% vs FEAM=10%, p<0.001). FEAM conditioning resulted in higher rates of gastrointestinal and infectious toxicities, including severe oral mucositis (grade ≥3: BEAM=31% vs FEAM=44%, p<0.001), and sepsis from Gram-negative bacteria (mean isolates/patient: BEAM=0.1 vs FEAM=0.19, p<0.001). Response status at day 100 post-ASCT (overall response: BEAM=91% vs FEAM=88%, p=0.42), 2-years Overall Survival (83.9%, 95%CI:81.5%-86.1%) and Progression-free Survival (70.3%, 95%CI:67.4%-73.1%) were not different in the two groups. Mortality from infection was higher in the FEAM group (SHR 1.99; 95%CI:1.02-3.88, p=0.04). BEAM and FEAM do not appear different in terms of survival and disease control. However, due to concerns of higher toxicity, Fotemustine substitution in BEAM does not seem justified, if not for easier supply. Copyright © 2018. Published by Elsevier Inc.

NLLSS: Predicting Synergistic Drug Combinations Based on Semi-supervised Learning

PubMed Central

Chen, Ming; Wang, Quanxin; Zhang, Lixin; Yan, Guiying

2016-01-01

Fungal infection has become one of the leading causes of hospital-acquired infections with high mortality rates. Furthermore, drug resistance is common for fungus-causing diseases. Synergistic drug combinations could provide an effective strategy to overcome drug resistance. Meanwhile, synergistic drug combinations can increase treatment efficacy and decrease drug dosage to avoid toxicity. Therefore, computational prediction of synergistic drug combinations for fungus-causing diseases becomes attractive. In this study, we proposed similar nature of drug combinations: principal drugs which obtain synergistic effect with similar adjuvant drugs are often similar and vice versa. Furthermore, we developed a novel algorithm termed Network-based Laplacian regularized Least Square Synergistic drug combination prediction (NLLSS) to predict potential synergistic drug combinations by integrating different kinds of information such as known synergistic drug combinations, drug-target interactions, and drug chemical structures. We applied NLLSS to predict antifungal synergistic drug combinations and showed that it achieved excellent performance both in terms of cross validation and independent prediction. Finally, we performed biological experiments for fungal pathogen Candida albicans to confirm 7 out of 13 predicted antifungal synergistic drug combinations. NLLSS provides an efficient strategy to identify potential synergistic antifungal combinations. PMID:27415801

Anti-tumor activities of luteolin and silibinin in glioblastoma cells: overexpression of miR-7-1-3p augmented luteolin and silibinin to inhibit autophagy and induce apoptosis in glioblastoma in vivo.

PubMed

Chakrabarti, Mrinmay; Ray, Swapan K

2016-03-01

Glioblastoma is the deadliest brain tumor in humans. High systemic toxicity of conventional chemotherapies prompted the search for natural compounds for controlling glioblastoma. The natural flavonoids luteolin (LUT) and silibinin (SIL) have anti-tumor activities. LUT inhibits autophagy, cell proliferation, metastasis, and angiogenesis and induces apoptosis; while SIL activates caspase-8 cascades to induce apoptosis. However, synergistic anti-tumor effects of LUT and SIL in glioblastoma remain unknown. Overexpression of tumor suppressor microRNA (miR) could enhance the anti-tumor effects of LUT and SIL. Here, we showed that 20 µM LUT and 50 µM SIL worked synergistically for inhibiting growth of two different human glioblastoma U87MG (wild-type p53) and T98G (mutant p53) cell lines and natural combination therapy was more effective than conventional chemotherapy (10 µM BCNU or 100 µM TMZ). Combination of LUT and SIL caused inhibition of growth of glioblastoma cells due to induction of significant amounts of apoptosis and complete inhibition of invasion and migration. Further, combination of LUT and SIL inhibited rapamycin (RAPA)-induced autophagy, a survival mechanism, with suppression of PKCα and promotion of apoptosis through down regulation of iNOS and significant increase in expression of the tumor suppressor miR-7-1-3p in glioblastoma cells. Our in vivo studies confirmed that overexpression of miR-7-1-3p augmented anti-tumor activities of LUT and SIL in RAPA pre-treated both U87MG and T98G tumors. In conclusion, our results clearly demonstrated that overexpression of miR-7-1-3p augmented the anti-tumor activities of LUT and SIL to inhibit autophagy and induce apoptosis for controlling growth of different human glioblastomas in vivo.

Predicting Drug Combination Index and Simulating the Network-Regulation Dynamics by Mathematical Modeling of Drug-Targeted EGFR-ERK Signaling Pathway

NASA Astrophysics Data System (ADS)

Huang, Lu; Jiang, Yuyang; Chen, Yuzong

2017-01-01

Synergistic drug combinations enable enhanced therapeutics. Their discovery typically involves the measurement and assessment of drug combination index (CI), which can be facilitated by the development and applications of in-silico CI predictive tools. In this work, we developed and tested the ability of a mathematical model of drug-targeted EGFR-ERK pathway in predicting CIs and in analyzing multiple synergistic drug combinations against observations. Our mathematical model was validated against the literature reported signaling, drug response dynamics, and EGFR-MEK drug combination effect. The predicted CIs and combination therapeutic effects of the EGFR-BRaf, BRaf-MEK, FTI-MEK, and FTI-BRaf inhibitor combinations showed consistent synergism. Our results suggest that existing pathway models may be potentially extended for developing drug-targeted pathway models to predict drug combination CI values, isobolograms, and drug-response surfaces as well as to analyze the dynamics of individual and combinations of drugs. With our model, the efficacy of potential drug combinations can be predicted. Our method complements the developed in-silico methods (e.g. the chemogenomic profile and the statistically-inferenced network models) by predicting drug combination effects from the perspectives of pathway dynamics using experimental or validated molecular kinetic constants, thereby facilitating the collective prediction of drug combination effects in diverse ranges of disease systems.

21 CFR 300.50 - Fixed-combination prescription drugs for humans.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Fixed-combination prescription drugs for humans. 300.50 Section 300.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE GENERAL Combination Drugs § 300.50 Fixed-combination prescription...

21 CFR 300.50 - Fixed-combination prescription drugs for humans.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Fixed-combination prescription drugs for humans. 300.50 Section 300.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE GENERAL Combination Drugs § 300.50 Fixed-combination prescription...

21 CFR 300.50 - Fixed-combination prescription drugs for humans.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Fixed-combination prescription drugs for humans. 300.50 Section 300.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE GENERAL Combination Drugs § 300.50 Fixed-combination prescription...

21 CFR 300.50 - Fixed-combination prescription drugs for humans.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Fixed-combination prescription drugs for humans. 300.50 Section 300.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE GENERAL Combination Drugs § 300.50 Fixed-combination prescription...

21 CFR 300.50 - Fixed-combination prescription drugs for humans.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Fixed-combination prescription drugs for humans. 300.50 Section 300.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE GENERAL Combination Drugs § 300.50 Fixed-combination prescription...

Effects of Drugs and Drug Combinations in Pigeons Trained to Discriminate among Pentobarbital, Dizocilpine, a Combination of These Drugs, and Saline

ERIC Educational Resources Information Center

McMillan, D. E.; Wessinger, William D.; Li, Mi

2009-01-01

Drugs with multiple actions can have complex discriminative-stimulus properties. An approach to studying such drugs is to train subjects to discriminate among drug combinations and individual drugs in the combination so that all of the complex discriminative stimuli are present during training. In the current experiments, a four-choice procedure…

The Human Kinome Targeted by FDA Approved Multi-Target Drugs and Combination Products: A Comparative Study from the Drug-Target Interaction Network Perspective.

PubMed

Li, Ying Hong; Wang, Pan Pan; Li, Xiao Xu; Yu, Chun Yan; Yang, Hong; Zhou, Jin; Xue, Wei Wei; Tan, Jun; Zhu, Feng

2016-01-01

The human kinome is one of the most productive classes of drug target, and there is emerging necessity for treating complex diseases by means of polypharmacology (multi-target drugs and combination products). However, the advantages of the multi-target drugs and the combination products are still under debate. A comparative analysis between FDA approved multi-target drugs and combination products, targeting the human kinome, was conducted by mapping targets onto the phylogenetic tree of the human kinome. The approach of network medicine illustrating the drug-target interactions was applied to identify popular targets of multi-target drugs and combination products. As identified, the multi-target drugs tended to inhibit target pairs in the human kinome, especially the receptor tyrosine kinase family, while the combination products were able to against targets of distant homology relationship. This finding asked for choosing the combination products as a better solution for designing drugs aiming at targets of distant homology relationship. Moreover, sub-networks of drug-target interactions in specific disease were generated, and mechanisms shared by multi-target drugs and combination products were identified. In conclusion, this study performed an analysis between approved multi-target drugs and combination products against the human kinome, which could assist the discovery of next generation polypharmacology.

Organic nanoparticle systems for spatiotemporal control of multimodal chemotherapy

PubMed Central

Meng, Fanfei; Han, Ning; Yeo, Yoon

2017-01-01

Introduction Chemotherapeutic drugs are used in combination to target multiple mechanisms involved in cancer cell survival and proliferation. Carriers are developed to deliver drug combinations to common target tissues in optimal ratios and desirable sequences. Nanoparticles (NP) have been a popular choice for this purpose due to their ability to increase the circulation half-life and tumor accumulation of a drug. Areas covered We review organic NP carriers based on polymers, proteins, peptides, and lipids for simultaneous delivery of multiple anticancer drugs, drug/sensitizer combinations, drug/photodynamic- or photothermal therapy combinations, and drug/gene therapeutics with examples in the past three years. Sequential delivery of drug combinations, based on either sequential administration or built-in release control, is introduced with an emphasis on the mechanistic understanding of such control. Expert opinion Recent studies demonstrate how a drug carrier can contribute to co-localizing drug combinations in optimal ratios and dosing sequences to maximize the synergistic effects. We identify several areas for improvement in future research, including the choice of drug combinations, circulation stability of carriers, spatiotemporal control of drug release, and the evaluation and clinical translation of combination delivery. PMID:27476442

High-throughput matrix screening identifies synergistic and antagonistic antimalarial drug combinations

PubMed Central

Mott, Bryan T.; Eastman, Richard T.; Guha, Rajarshi; Sherlach, Katy S.; Siriwardana, Amila; Shinn, Paul; McKnight, Crystal; Michael, Sam; Lacerda-Queiroz, Norinne; Patel, Paresma R.; Khine, Pwint; Sun, Hongmao; Kasbekar, Monica; Aghdam, Nima; Fontaine, Shaun D.; Liu, Dongbo; Mierzwa, Tim; Mathews-Griner, Lesley A.; Ferrer, Marc; Renslo, Adam R.; Inglese, James; Yuan, Jing; Roepe, Paul D.; Su, Xin-zhuan; Thomas, Craig J.

2015-01-01

Drug resistance in Plasmodium parasites is a constant threat. Novel therapeutics, especially new drug combinations, must be identified at a faster rate. In response to the urgent need for new antimalarial drug combinations we screened a large collection of approved and investigational drugs, tested 13,910 drug pairs, and identified many promising antimalarial drug combinations. The activity of known antimalarial drug regimens was confirmed and a myriad of new classes of positively interacting drug pairings were discovered. Network and clustering analyses reinforced established mechanistic relationships for known drug combinations and identified several novel mechanistic hypotheses. From eleven screens comprising >4,600 combinations per parasite strain (including duplicates) we further investigated interactions between approved antimalarials, calcium homeostasis modulators, and inhibitors of phosphatidylinositide 3-kinases (PI3K) and the mammalian target of rapamycin (mTOR). These studies highlight important targets and pathways and provide promising leads for clinically actionable antimalarial therapy. PMID:26403635

Identification of drug combinations administered by continuous subcutaneous infusion that require analysis for compatibility and stability.

PubMed

Dickman, Andrew; Bickerstaff, Matthew; Jackson, Richard; Schneider, Jennifer; Mason, Stephen; Ellershaw, John

2017-03-23

A continuous subcutaneous infusion (CSCI) delivered via syringe pump is a method of drug administration used to maintain symptom control when a patient is no longer able to tolerate oral medication. Several classes of drugs, such as opioids, antiemetics, anticholinergics, antipsychotics and benzodiazepines are routinely administered by CSCI alone or in combinations. Previous studies attempting to identify the most-common CSCI combinations are now several years old and no longer reflect current clinical practice. The aim of this work was to review current clinical practice and identify CSCI drug combinations requiring analysis for chemical compatibility and stability. UK pharmacy professionals involved in the delivery of care to palliative patients in hospitals and hospices were invited to enter CSCI combinations comprised of two or more drugs onto an electronic database over a 12-month period. In addition, a separate Delphi study with a panel of 15 expert healthcare professionals was completed to identify a maximum of five combinations of drugs used to treat more complex, but less commonly encountered symptoms unlikely to be identified by the national survey. A total of 57 individuals representing 33 separate palliative care services entered 1,945 drug combinations suitable for analysis, with 278 discrete combinations identified. The top 40 drug combinations represented nearly two-thirds of combinations recorded. A total of 23 different drugs were administered in combination and the median number of drugs in a combination was three. The Delphi study identified five combinations for the relief of complex or refractory symptoms. This study represents the first step towards developing authoritative national guidance on the administration of drugs by CSCI. Further work will ensure healthcare practitioners have the knowledge and confidence that a prescribed combination will be both safe and efficacious.

Experimental design and statistical analysis for three-drug combination studies.

PubMed

Fang, Hong-Bin; Chen, Xuerong; Pei, Xin-Yan; Grant, Steven; Tan, Ming

2017-06-01

Drug combination is a critically important therapeutic approach for complex diseases such as cancer and HIV due to its potential for efficacy at lower, less toxic doses and the need to move new therapies rapidly into clinical trials. One of the key issues is to identify which combinations are additive, synergistic, or antagonistic. While the value of multidrug combinations has been well recognized in the cancer research community, to our best knowledge, all existing experimental studies rely on fixing the dose of one drug to reduce the dimensionality, e.g. looking at pairwise two-drug combinations, a suboptimal design. Hence, there is an urgent need to develop experimental design and analysis methods for studying multidrug combinations directly. Because the complexity of the problem increases exponentially with the number of constituent drugs, there has been little progress in the development of methods for the design and analysis of high-dimensional drug combinations. In fact, contrary to common mathematical reasoning, the case of three-drug combinations is fundamentally more difficult than two-drug combinations. Apparently, finding doses of the combination, number of combinations, and replicates needed to detect departures from additivity depends on dose-response shapes of individual constituent drugs. Thus, different classes of drugs of different dose-response shapes need to be treated as a separate case. Our application and case studies develop dose finding and sample size method for detecting departures from additivity with several common (linear and log-linear) classes of single dose-response curves. Furthermore, utilizing the geometric features of the interaction index, we propose a nonparametric model to estimate the interaction index surface by B-spine approximation and derive its asymptotic properties. Utilizing the method, we designed and analyzed a combination study of three anticancer drugs, PD184, HA14-1, and CEP3891 inhibiting myeloma H929 cell line. To our best knowledge, this is the first ever three drug combinations study performed based on the original 4D dose-response surface formed by dose ranges of three drugs.

78 FR 41999 - Combined Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-15

.... No. 120-1] RIN 2120-AK01 Combined Drug and Alcohol Testing Programs AGENCY: Federal Aviation... or on-demand operators that also conduct commercial air tour operations to combine the drug and... 13, 2013. Any currently held exemptions allowing part 121 or part 135 operators to combine their drug...

Experimental Design for Multi-drug Combination Studies Using Signaling Networks

PubMed Central

Huang, Hengzhen; Fang, Hong-Bin; Tan, Ming T.

2017-01-01

Summary Combinations of multiple drugs are an important approach to maximize the chance for therapeutic success by inhibiting multiple pathways/targets. Analytic methods for studying drug combinations have received increasing attention because major advances in biomedical research have made available large number of potential agents for testing. The preclinical experiment on multi-drug combinations plays a key role in (especially cancer) drug development because of the complex nature of the disease, the need to reduce development time and costs. Despite recent progresses in statistical methods for assessing drug interaction, there is an acute lack of methods for designing experiments on multi-drug combinations. The number of combinations grows exponentially with the number of drugs and dose-levels and it quickly precludes laboratory testing. Utilizing experimental dose-response data of single drugs and a few combinations along with pathway/network information to obtain an estimate of the functional structure of the dose-response relationship in silico, we propose an optimal design that allows exploration of the dose-effect surface with the smallest possible sample size in this paper. The simulation studies show our proposed methods perform well. PMID:28960231

Discovering Synergistic Drug Combination from a Computational Perspective.

PubMed

Ding, Pingjian; Luo, Jiawei; Liang, Cheng; Xiao, Qiu; Cao, Buwen; Li, Guanghui

2018-03-30

Synergistic drug combinations play an important role in the treatment of complex diseases. The identification of effective drug combination is vital to further reduce the side effects and improve therapeutic efficiency. In previous years, in vitro method has been the main route to discover synergistic drug combinations. However, many limitations of time and resource consumption lie within the in vitro method. Therefore, with the rapid development of computational models and the explosive growth of large and phenotypic data, computational methods for discovering synergistic drug combinations are an efficient and promising tool and contribute to precision medicine. It is the key of computational methods how to construct the computational model. Different computational strategies generate different performance. In this review, the recent advancements in computational methods for predicting effective drug combination are concluded from multiple aspects. First, various datasets utilized to discover synergistic drug combinations are summarized. Second, we discussed feature-based approaches and partitioned these methods into two classes including feature-based methods in terms of similarity measure, and feature-based methods in terms of machine learning. Third, we discussed network-based approaches for uncovering synergistic drug combinations. Finally, we analyzed and prospected computational methods for predicting effective drug combinations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Recent Advances of Cocktail Chemotherapy by Combination Drug Delivery Systems

PubMed Central

Hu, Quanyin; Sun, Wujin; Wang, Chao; Gu, Zhen

2016-01-01

Combination chemotherapy is widely exploited for enhanced cancer treatment in clinic. However, the traditional cocktail administration of combination regimens often suffers from varying pharmacokinetics among different drugs. The emergence of nanotechnology offers an unparalleled opportunity for developing advanced combination drug delivery strategies with the ability to encapsulate various drugs simultaneously and unify the pharmacokinetics of each drug. This review surveys the most recent advances in combination delivery of multiple small molecule chemotherapeutics using nanocarriers. The mechanisms underlying combination chemotherapy, including the synergistic, additive and potentiation effects, are also discussed with typical examples. We further highlight the sequential and site-specific co-delivery strategies, which provide new guidelines for development of programmable combination drug delivery systems. Clinical outlook and challenges are also discussed in the end. PMID:26546751

Nanomedicine of synergistic drug combinations for cancer therapy – strategies and perspectives

PubMed Central

Xue, Hui Yi; Eoh, June Young; Wu, Xiao Yu

2016-01-01

Nanomedicine of synergistic drug combinations has shown increasing significance in cancer therapy due to its promise in providing superior therapeutic benefits to the current drug combination therapy used in clinical practice. In this article, we will examine the rationale, principles, and advantages of applying nanocarriers to improve anticancer drug combination therapy, review the use of nanocarriers for delivery of a variety of combinations of different classes of anticancer agents including small molecule drugs and biologics, and discuss the challenges and future perspectives of the nanocarrier-based combination therapy. The goal of this review is to provide better understanding of this increasingly important new paradigm of cancer treatment and key considerations for rational design of nanomedicine of synergistic drug combinations for cancer therapy. PMID:27287891

Large-scale exploration and analysis of drug combinations.

PubMed

Li, Peng; Huang, Chao; Fu, Yingxue; Wang, Jinan; Wu, Ziyin; Ru, Jinlong; Zheng, Chunli; Guo, Zihu; Chen, Xuetong; Zhou, Wei; Zhang, Wenjuan; Li, Yan; Chen, Jianxin; Lu, Aiping; Wang, Yonghua

2015-06-15

Drug combinations are a promising strategy for combating complex diseases by improving the efficacy and reducing corresponding side effects. Currently, a widely studied problem in pharmacology is to predict effective drug combinations, either through empirically screening in clinic or pure experimental trials. However, the large-scale prediction of drug combination by a systems method is rarely considered. We report a systems pharmacology framework to predict drug combinations (PreDCs) on a computational model, termed probability ensemble approach (PEA), for analysis of both the efficacy and adverse effects of drug combinations. First, a Bayesian network integrating with a similarity algorithm is developed to model the combinations from drug molecular and pharmacological phenotypes, and the predictions are then assessed with both clinical efficacy and adverse effects. It is illustrated that PEA can predict the combination efficacy of drugs spanning different therapeutic classes with high specificity and sensitivity (AUC = 0.90), which was further validated by independent data or new experimental assays. PEA also evaluates the adverse effects (AUC = 0.95) quantitatively and detects the therapeutic indications for drug combinations. Finally, the PreDC database includes 1571 known and 3269 predicted optimal combinations as well as their potential side effects and therapeutic indications. The PreDC database is available at http://sm.nwsuaf.edu.cn/lsp/predc.php. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Polydrug use among club-going young adults recruited through time-space sampling

PubMed Central

Grov, Christian; Kelly, Brian C.; Parsons, Jeffrey T.

2009-01-01

Though some researchers have indicated club drug users are more likely to be polydrug users, there remains little known about the prevalence and specific combinations of the substances they use. Between 2004-2006, and using time-space sampling, a stratified sample of 400 18-29 year old New York City club-going drug-using young adults were recruited into the Club Drugs and Health Project. Most participants (91.7%) had engaged in polydrug use and 1,670 combinations of drugs were reported. Ecstasy (86.6% of users) and cocaine (85.7% of users) were the two most frequently reported club drugs used in combination with other substances. In terms of poly-club-drug combinations, ecstasy appeared to be the “universal compliment” as this drug was most often cited in combinations with other club drugs (specifically ecstasy + ketamine, ecstasy + cocaine, ecstasy + GHB). Other frequently cited drug combinations included cocaine and marijuana, ecstasy and marijuana, LSD and marijuana, and cocaine and alcohol. These data highlight the need to develop drug health education and prevention messages targeted at polydrug use. PMID:19444726

Treatment of mycosis fungoides with topical nitrosourea compounds: Further studies.

PubMed

Zackheim, H S; Epstein, E H

1975-12-01

Twenty-six patients with mycosis fungoides were treated topically with three nitrosourea compounds: carmustine (BCNU), lomustine (CCNU), and 1-methyl-1-nitrosourea. A high percentage experienced good to excellent results. Remissions following treatment of individual lesions varied from one month to at least three years. Remissions following total body surface treatment varied from two weeks to at least four months. Two of 13 patients treated over the entire body suffered temporary bone marrow depression, indluding one with severe pancytopenia. This toxic effect was attributed to lomustine and was not seen in patients treated with carmustine alone. Thirteen patients highly allergic to mechlorethamine hydrochloride showed no cross-sensitivity to nitrosourea compounds. A primary irritant dermatitis occurred in about one half of the patients and telangiectasia in two. Two patients developed hypersensitivity to nitrosourea compounds. Carmustine is the preferred nitrosourea compound for topical therapy of mycosis fungoides.

Superoxide dismutase and catalase protect cultured hepatocytes from the cytotoxicity of acetaminophen.

PubMed

Kyle, M E; Miccadei, S; Nakae, D; Farber, J L

1987-12-31

Superoxide dismutase, catalase and mannitol prevent the killing of cultured hepatocytes by acetaminophen in the presence of an inhibitor of glutathione reductase, BCNU. Under these conditions, the cytotoxicity of acetaminophen depends upon its metabolism, since beta-naphthoflavone, an inhibitor of mixed function oxidation, prevents the cell killing. In hepatocytes made resistant to acetaminophen by pretreatment with the ferric iron chelator, deferoxamine, addition of ferric or ferrous iron restores the sensitivity to acetaminophen. In such a situation, both superoxide dismutase and catalase prevent the killing by acetaminophen in the presence of ferric iron. By contrast, catalase, but not superoxide dismutase, prevents the cell killing dependent upon addition of ferrous iron. These results document the participation of both superoxide anion and hydrogen peroxide in the killing of cultured hepatocytes by acetaminophen and suggest that hydroxyl radicals generated by an iron catalyzed Haber-Weiss reaction mediate the cell injury.

Discovery and Delivery of Synergistic Chemotherapy Drug Combinations to Tumors

NASA Astrophysics Data System (ADS)

Camacho, Kathryn Militar

Chemotherapy combinations for cancer treatments harbor immense therapeutic potentials which have largely been untapped. Of all diseases, clinical studies of drug combinations are the most prevalent in oncology, yet their effectiveness is disputable, as complete tumor regressions are rare. Our research has been devoted towards developing delivery vehicles for combinations of chemotherapy drugs which elicit significant tumor reduction yet limit toxicity in healthy tissue. Current administration methods assume that chemotherapy combinations at maximum tolerable doses will provide the greatest therapeutic effect -- a presumption which often leads to unprecedented side effects. Contrary to traditional administration, we have found that drug ratios rather than total cumulative doses govern combination therapeutic efficacy. In this thesis, we have developed nanoparticles to incorporate synergistic ratios of chemotherapy combinations which significantly inhibit cancer cell growth at lower doses than would be required for their single drug counterparts. The advantages of multi-drug incorporation in nano-vehicles are many: improved accumulation in tumor tissue via the enhanced permeation and retention effect, limited uptake in healthy tissue, and controlled exposure of tumor tissue to optimal synergistic drug ratios. To exploit these advantages for polychemotherapy delivery, two prominent nanoparticles were investigated: liposomes and polymer-drug conjugates. Liposomes represent the oldest class of nanoparticles, with high drug loading capacities and excellent biocompatibility. Polymer-drug conjugates offer controlled drug incorporations through reaction stoichiometry, and potentially allow for delivery of precise ratios. Here, we show that both vehicles, when armed with synergistic ratios of chemotherapy drugs, significantly inhibit tumor growth in an aggressive mouse breast carcinoma model. Furthermore, versatile drug incorporation methods investigated here can be broadly applied to various agents. Findings from our research can potentially widen the therapeutic window of chemotherapy combinations by emphasizing investigations of optimal drug ratios rather than maximum drug doses and by identifying appropriate nanoparticles for their delivery. Application of these concepts can ultimately help capture the full therapeutic potential of combination regimens.

Polymeric micelles for multi-drug delivery in cancer.

PubMed

Cho, Hyunah; Lai, Tsz Chung; Tomoda, Keishiro; Kwon, Glen S

2015-02-01

Drug combinations are common in cancer treatment and are rapidly evolving, moving beyond chemotherapy combinations to combinations of signal transduction inhibitors. For the delivery of drug combinations, i.e., multi-drug delivery, major considerations are synergy, dose regimen (concurrent versus sequential), pharmacokinetics, toxicity, and safety. In this contribution, we review recent research on polymeric micelles for multi-drug delivery in cancer. In concurrent drug delivery, polymeric micelles deliver multi-poorly water-soluble anticancer agents, satisfying strict requirements in solubility, stability, and safety. In sequential drug delivery, polymeric micelles participate in pretreatment strategies that "prime" solid tumors and enhance the penetration of secondarily administered anticancer agent or nanocarrier. The improved delivery of multiple poorly water-soluble anticancer agents by polymeric micelles via concurrent or sequential regimens offers novel and interesting strategies for drug combinations in cancer treatment.

Powerful Behavioral Interactions Between Methamphetamine and Morphine

PubMed Central

Trujillo, Keith A.; Smith, Monique L.; Guaderrama, Melissa M.

2011-01-01

Use of drugs of abuse in combination is common among recreational users and addicts. The combination of a psychomotor stimulant with an opiate, known as a ‘speedball’, reportedly produces greater effects than either drug alone and has been responsible for numerous deaths. Historically, the most popular speedball combination is that of cocaine and heroin. However, with the growing popularity of methamphetamine in recent years, there has been increased use of this drug in combination with other drugs of abuse, including opiates. Despite this, relatively little research has examined interactions between methamphetamine and opiates. In the current research, behavioral interactions between methamphetamine and the prototypical opiate, morphine, were examined across a variety of dose combinations in Sprague-Dawley rats. The combination of methamphetamine and morphine produced stimulation of behavior that was dramatically higher than either drug alone; however, the magnitude of the interaction was dependent on the dose of the drugs and the specific behaviors examined. The results demonstrate complex behavioral interactions between these drugs, but are consistent with the idea that this combination is used because it produces a greater effect than either drug alone. PMID:21549146

An application of a Hill-based response surface model for a drug combination experiment on lung cancer.

PubMed

Ning, Shaoyang; Xu, Hongquan; Al-Shyoukh, Ibrahim; Feng, Jiaying; Sun, Ren

2014-10-30

Combination chemotherapy with multiple drugs has been widely applied to cancer treatment owing to enhanced efficacy and reduced drug resistance. For drug combination experiment analysis, response surface modeling has been commonly adopted. In this paper, we introduce a Hill-based global response surface model and provide an application of the model to a 512-run drug combination experiment with three chemicals, namely AG490, U0126, and indirubin-3  ' -monoxime (I-3-M), on lung cancer cells. The results demonstrate generally improved goodness of fit of our model from the traditional polynomial model, as well as the original Hill model on the basis of fixed-ratio drug combinations. We identify different dose-effect patterns between normal and cancer cells on the basis of our model, which indicates the potential effectiveness of the drug combination in cancer treatment. Meanwhile, drug interactions are analyzed both qualitatively and quantitatively. The distinct interaction patterns between U0126 and I-3-M on two types of cells uncovered by the model could be a further indicator of the efficacy of the drug combination. Copyright © 2014 John Wiley & Sons, Ltd.

Informatics Approaches for Predicting, Understanding, and Testing Cancer Drug Combinations.

PubMed

Tang, Jing

2017-01-01

Making cancer treatment more effective is one of the grand challenges in our health care system. However, many drugs have entered clinical trials but so far showed limited efficacy or induced rapid development of resistance. We urgently need multi-targeted drug combinations, which shall selectively inhibit the cancer cells and block the emergence of drug resistance. The book chapter focuses on mathematical and computational tools to facilitate the discovery of the most promising drug combinations to improve efficacy and prevent resistance. Data integration approaches that leverage drug-target interactions, cancer molecular features, and signaling pathways for predicting, understanding, and testing drug combinations are critically reviewed.

Adaptive reference update (ARU) algorithm. A stochastic search algorithm for efficient optimization of multi-drug cocktails

PubMed Central

2012-01-01

Background Multi-target therapeutics has been shown to be effective for treating complex diseases, and currently, it is a common practice to combine multiple drugs to treat such diseases to optimize the therapeutic outcomes. However, considering the huge number of possible ways to mix multiple drugs at different concentrations, it is practically difficult to identify the optimal drug combination through exhaustive testing. Results In this paper, we propose a novel stochastic search algorithm, called the adaptive reference update (ARU) algorithm, that can provide an efficient and systematic way for optimizing multi-drug cocktails. The ARU algorithm iteratively updates the drug combination to improve its response, where the update is made by comparing the response of the current combination with that of a reference combination, based on which the beneficial update direction is predicted. The reference combination is continuously updated based on the drug response values observed in the past, thereby adapting to the underlying drug response function. To demonstrate the effectiveness of the proposed algorithm, we evaluated its performance based on various multi-dimensional drug functions and compared it with existing algorithms. Conclusions Simulation results show that the ARU algorithm significantly outperforms existing stochastic search algorithms, including the Gur Game algorithm. In fact, the ARU algorithm can more effectively identify potent drug combinations and it typically spends fewer iterations for finding effective combinations. Furthermore, the ARU algorithm is robust to random fluctuations and noise in the measured drug response, which makes the algorithm well-suited for practical drug optimization applications. PMID:23134742

Correlation of tumor p53 and PCNA with response and survival of glioblastoma in patients treated with an ECOG protocol of pre-irradiation chemotherapy.

PubMed

Grunnet, M L; O'Neill, A; Gilbert, M; Hellman, R

2000-01-01

The ability to predict treatment responsiveness and survival of patients with glioblastoma multiforme, the most malignant and most common primary brain tumor, would be a valuable asset. Tumor and proliferation markers such as p53 and PCNA have been immunohistochemically defined and have been useful in other tumors in determining prognosis. Therefore, the authors studied the correlation of responsiveness to treatment, time to progression and survival with p53 and PCNA labeling indices in a pre-irradiation chemotherapy study of the glioblastoma multiforme. Immunohistopathology for labeling indices for p53 and PCNA using formalin-fixed, paraffin-embedded tissue from the glioblastomas of 23 patients entered into a phase II ECOG trial of pre-irradiation chemotherapy were defined using the streptavidin-peroxidase technique with AEC chromogen. The labeling indices were correlated with response to treatment time to progression and overall survival. Most patients received three cycles of BCNU for three days over three months and cisplatin monthly for three days over three months prior to external beam irradiation. There were no significant differences in treatment response, time to progression or overall survival in glioblastoma, patients with positive p53 labeling index (> 5%) versus a negative p53 labeling index (< or = 5%) or positive PCNA labeling (> 10%) versus a negative labeling index (< or = 10%) or any combination of P53 and PCNA labeling indices. Using this protocol of pre-irradiation chemotherapy, p53 and PCNA labeling indices in the glioblastoma multiforme did not predict treatment benefit.

DRUG-NEM: Optimizing drug combinations using single-cell perturbation response to account for intratumoral heterogeneity

PubMed Central

Anchang, Benedict; Davis, Kara L.; Fienberg, Harris G.; Bendall, Sean C.; Karacosta, Loukia G.; Tibshirani, Robert; Nolan, Garry P.; Plevritis, Sylvia K.

2018-01-01

An individual malignant tumor is composed of a heterogeneous collection of single cells with distinct molecular and phenotypic features, a phenomenon termed intratumoral heterogeneity. Intratumoral heterogeneity poses challenges for cancer treatment, motivating the need for combination therapies. Single-cell technologies are now available to guide effective drug combinations by accounting for intratumoral heterogeneity through the analysis of the signaling perturbations of an individual tumor sample screened by a drug panel. In particular, Mass Cytometry Time-of-Flight (CyTOF) is a high-throughput single-cell technology that enables the simultaneous measurements of multiple (>40) intracellular and surface markers at the level of single cells for hundreds of thousands of cells in a sample. We developed a computational framework, entitled Drug Nested Effects Models (DRUG-NEM), to analyze CyTOF single-drug perturbation data for the purpose of individualizing drug combinations. DRUG-NEM optimizes drug combinations by choosing the minimum number of drugs that produce the maximal desired intracellular effects based on nested effects modeling. We demonstrate the performance of DRUG-NEM using single-cell drug perturbation data from tumor cell lines and primary leukemia samples. PMID:29654148

Drug Synergy of Tenofovir and Nanoparticle-Based Antiretrovirals for HIV Prophylaxis

PubMed Central

Chaowanachan, Thanyanan; Krogstad, Emily; Ball, Cameron; Woodrow, Kim A.

2013-01-01

Background The use of drug combinations has revolutionized the treatment of HIV but there is no equivalent combination product that exists for prevention, particularly for topical HIV prevention. Strategies to combine chemically incompatible agents may facilitate the discovery of unique drug-drug activities, particularly unexplored combination drug synergy. We fabricated two types of nanoparticles, each loaded with a single antiretroviral (ARV) that acts on a specific step of the viral replication cycle. Here we show unique combination drug activities mediated by our polymeric delivery systems when combined with free tenofovir (TFV). Methodology/Principal Findings Biodegradable poly(lactide-co-glycolide) nanoparticles loaded with efavirenz (NP-EFV) or saquinavir (NP-SQV) were individually prepared by emulsion or nanoprecipitation techniques. Nanoparticles had reproducible size (d ∼200 nm) and zeta potential (-25 mV). The drug loading of the nanoparticles was approximately 7% (w/w). NP-EFV and NP-SQV were nontoxic to TZM-bl cells and ectocervical explants. Both NP-EFV and NP-SQV exhibited potent protection against HIV-1 BaL infection in vitro. The HIV inhibitory effect of nanoparticle formulated ARVs showed up to a 50-fold reduction in the 50% inhibitory concentration (IC50) compared to free drug. To quantify the activity arising from delivery of drug combinations, we calculated combination indices (CI) according to the median-effect principle. NP-EFV combined with free TFV demonstrated strong synergistic effects (CI50 = 0.07) at a 1∶50 ratio of IC50 values and additive effects (CI50 = 1.05) at a 1∶1 ratio of IC50 values. TFV combined with NP-SQV at a 1∶1 ratio of IC50 values also showed strong synergy (CI50 = 0.07). Conclusions ARVs with different physicochemical properties can be encapsulated individually into nanoparticles to potently inhibit HIV. Our findings demonstrate for the first time that combining TFV with either NP-EFV or NP-SQV results in pronounced combination drug effects, and emphasize the potential of nanoparticles for the realization of unique drug-drug activities. PMID:23630586

77 FR 39194 - Combined Drug and Alcohol Testing Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-02

...-0688; Notice No. 12-04] RIN 2120-AK01 Combined Drug and Alcohol Testing Programs AGENCY: Federal... tour operations to combine the drug and alcohol testing required for each operation into one testing... programs while maintaining the level of safety intended by the current drug and alcohol testing regulations...

21 CFR 333.320 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Permitted combinations of active ingredients. 333.320 Section 333.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Topical Acne Drug Products § 333.320 Permitted combinations of active ingredients. (a) Resorcinol...

21 CFR 333.320 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Permitted combinations of active ingredients. 333.320 Section 333.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Topical Acne Drug Products § 333.320 Permitted combinations of active ingredients. (a) Resorcinol...

21 CFR 333.320 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Permitted combinations of active ingredients. 333.320 Section 333.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Topical Acne Drug Products § 333.320 Permitted combinations of active ingredients. (a) Resorcinol...

21 CFR 333.320 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Permitted combinations of active ingredients. 333.320 Section 333.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Topical Acne Drug Products § 333.320 Permitted combinations of active ingredients. (a) Resorcinol...

Recent Advances in Delivery of Drug-Nucleic Acid Combinations for Cancer Treatment

PubMed Central

Li, Jing; Wang, Yan; Zhu, Yu; Oupický, David

2013-01-01

Cancer treatment that uses a combination of approaches with the ability to affect multiple disease pathways has been proven highly effective in the treatment of many cancers. Combination therapy can include multiple chemotherapeutics or combinations of chemotherapeutics with other treatment modalities like surgery or radiation. However, despite the widespread clinical use of combination therapies, relatively little attention has been given to the potential of modern nanocarrier delivery methods, like liposomes, micelles, and nanoparticles, to enhance the efficacy of combination treatments. This lack of knowledge is particularly notable in the limited success of vectors for the delivery of combinations of nucleic acids with traditional small molecule drugs. The delivery of drug-nucleic acid combinations is particularly challenging due to differences in the physicochemical properties of the two types of agents. This review discusses recent advances in the development of delivery methods using combinations of small molecule drugs and nucleic acid therapeutics to treat cancer. This review primarily focuses on the rationale used for selecting appropriate drug-nucleic acid combinations as well as progress in the development of nanocarriers suitable for simultaneous delivery of drug-nucleic acid combinations. PMID:23624358

Recent advances in delivery of drug-nucleic acid combinations for cancer treatment.

PubMed

Li, Jing; Wang, Yan; Zhu, Yu; Oupický, David

2013-12-10

Cancer treatment that uses a combination of approaches with the ability to affect multiple disease pathways has been proven highly effective in the treatment of many cancers. Combination therapy can include multiple chemotherapeutics or combinations of chemotherapeutics with other treatment modalities like surgery or radiation. However, despite the widespread clinical use of combination therapies, relatively little attention has been given to the potential of modern nanocarrier delivery methods, like liposomes, micelles, and nanoparticles, to enhance the efficacy of combination treatments. This lack of knowledge is particularly notable in the limited success of vectors for the delivery of combinations of nucleic acids with traditional small molecule drugs. The delivery of drug-nucleic acid combinations is particularly challenging due to differences in the physicochemical properties of the two types of agents. This review discusses recent advances in the development of delivery methods using combinations of small molecule drugs and nucleic acid therapeutics to treat cancer. This review primarily focuses on the rationale used for selecting appropriate drug-nucleic acid combinations as well as progress in the development of nanocarriers suitable for simultaneous delivery of drug-nucleic acid combinations. Copyright © 2013 Elsevier B.V. All rights reserved.

Prediction of Effective Drug Combinations by an Improved Naïve Bayesian Algorithm.

PubMed

Bai, Li-Yue; Dai, Hao; Xu, Qin; Junaid, Muhammad; Peng, Shao-Liang; Zhu, Xiaolei; Xiong, Yi; Wei, Dong-Qing

2018-02-05

Drug combinatorial therapy is a promising strategy for combating complex diseases due to its fewer side effects, lower toxicity and better efficacy. However, it is not feasible to determine all the effective drug combinations in the vast space of possible combinations given the increasing number of approved drugs in the market, since the experimental methods for identification of effective drug combinations are both labor- and time-consuming. In this study, we conducted systematic analysis of various types of features to characterize pairs of drugs. These features included information about the targets of the drugs, the pathway in which the target protein of a drug was involved in, side effects of drugs, metabolic enzymes of the drugs, and drug transporters. The latter two features (metabolic enzymes and drug transporters) were related to the metabolism and transportation properties of drugs, which were not analyzed or used in previous studies. Then, we devised a novel improved naïve Bayesian algorithm to construct classification models to predict effective drug combinations by using the individual types of features mentioned above. Our results indicated that the performance of our proposed method was indeed better than the naïve Bayesian algorithm and other conventional classification algorithms such as support vector machine and K-nearest neighbor.

PDC-SGB: Prediction of effective drug combinations using a stochastic gradient boosting algorithm.

PubMed

Xu, Qian; Xiong, Yi; Dai, Hao; Kumari, Kotni Meena; Xu, Qin; Ou, Hong-Yu; Wei, Dong-Qing

2017-03-21

Combinatorial therapy is a promising strategy for combating complex diseases by improving the efficacy and reducing the side effects. To facilitate the identification of drug combinations in pharmacology, we proposed a new computational model, termed PDC-SGB, to predict effective drug combinations by integrating biological, chemical and pharmacological information based on a stochastic gradient boosting algorithm. To begin with, a set of 352 golden positive samples were collected from the public drug combination database. Then, a set of 732 dimensional feature vector involving biological, chemical and pharmaceutical information was constructed for each drug combination to describe its properties. To avoid overfitting, the maximum relevance & minimum redundancy (mRMR) method was performed to extract useful ones by removing redundant subsets. Based on the selected features, the three different type of classification algorithms were employed to build the drug combination prediction models. Our results demonstrated that the model based on the stochastic gradient boosting algorithm yield out the best performance. Furthermore, it is indicated that the feature patterns of therapy had powerful ability to discriminate effective drug combinations from non-effective ones. By analyzing various features, it is shown that the enriched features occurred frequently in golden positive samples can help predict novel drug combinations. Copyright © 2017 Elsevier Ltd. All rights reserved.

21 CFR 349.30 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Permitted combinations of active ingredients. 349... SERVICES (CONTINUED) DRUGS FOR HUMAN USE OPHTHALMIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 349.30 Permitted combinations of active ingredients. The following combinations are permitted...

21 CFR 349.30 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Permitted combinations of active ingredients. 349... SERVICES (CONTINUED) DRUGS FOR HUMAN USE OPHTHALMIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 349.30 Permitted combinations of active ingredients. The following combinations are permitted...

21 CFR 349.30 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Permitted combinations of active ingredients. 349... SERVICES (CONTINUED) DRUGS FOR HUMAN USE OPHTHALMIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 349.30 Permitted combinations of active ingredients. The following combinations are permitted...

21 CFR 349.30 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Permitted combinations of active ingredients. 349... SERVICES (CONTINUED) DRUGS FOR HUMAN USE OPHTHALMIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 349.30 Permitted combinations of active ingredients. The following combinations are permitted...

21 CFR 349.30 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Permitted combinations of active ingredients. 349... SERVICES (CONTINUED) DRUGS FOR HUMAN USE OPHTHALMIC DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 349.30 Permitted combinations of active ingredients. The following combinations are permitted...

21 CFR 333.160 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of permitted combinations of active ingredients. 333.160 Section 333.160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... HUMAN USE First Aid Antibiotic Drug Products § 333.160 Labeling of permitted combinations of active...

21 CFR 333.160 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of permitted combinations of active ingredients. 333.160 Section 333.160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... HUMAN USE First Aid Antibiotic Drug Products § 333.160 Labeling of permitted combinations of active...

21 CFR 333.160 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of permitted combinations of active ingredients. 333.160 Section 333.160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... HUMAN USE First Aid Antibiotic Drug Products § 333.160 Labeling of permitted combinations of active...

A hadoop-based method to predict potential effective drug combination.

PubMed

Sun, Yifan; Xiong, Yi; Xu, Qian; Wei, Dongqing

2014-01-01

Combination drugs that impact multiple targets simultaneously are promising candidates for combating complex diseases due to their improved efficacy and reduced side effects. However, exhaustive screening of all possible drug combinations is extremely time-consuming and impractical. Here, we present a novel Hadoop-based approach to predict drug combinations by taking advantage of the MapReduce programming model, which leads to an improvement of scalability of the prediction algorithm. By integrating the gene expression data of multiple drugs, we constructed data preprocessing and the support vector machines and naïve Bayesian classifiers on Hadoop for prediction of drug combinations. The experimental results suggest that our Hadoop-based model achieves much higher efficiency in the big data processing steps with satisfactory performance. We believed that our proposed approach can help accelerate the prediction of potential effective drugs with the increasing of the combination number at an exponential rate in future. The source code and datasets are available upon request.

A Hadoop-Based Method to Predict Potential Effective Drug Combination

PubMed Central

Xiong, Yi; Xu, Qian; Wei, Dongqing

2014-01-01

Combination drugs that impact multiple targets simultaneously are promising candidates for combating complex diseases due to their improved efficacy and reduced side effects. However, exhaustive screening of all possible drug combinations is extremely time-consuming and impractical. Here, we present a novel Hadoop-based approach to predict drug combinations by taking advantage of the MapReduce programming model, which leads to an improvement of scalability of the prediction algorithm. By integrating the gene expression data of multiple drugs, we constructed data preprocessing and the support vector machines and naïve Bayesian classifiers on Hadoop for prediction of drug combinations. The experimental results suggest that our Hadoop-based model achieves much higher efficiency in the big data processing steps with satisfactory performance. We believed that our proposed approach can help accelerate the prediction of potential effective drugs with the increasing of the combination number at an exponential rate in future. The source code and datasets are available upon request. PMID:25147789

Antagonism between Bacteriostatic and Bactericidal Antibiotics Is Prevalent

PubMed Central

Lázár, Viktória; Papp, Balázs; Arnoldini, Markus; Abel zur Wiesch, Pia; Busa-Fekete, Róbert; Fekete, Gergely; Pál, Csaba; Ackermann, Martin; Bonhoeffer, Sebastian

2014-01-01

Combination therapy is rarely used to counter the evolution of resistance in bacterial infections. Expansion of the use of combination therapy requires knowledge of how drugs interact at inhibitory concentrations. More than 50 years ago, it was noted that, if bactericidal drugs are most potent with actively dividing cells, then the inhibition of growth induced by a bacteriostatic drug should result in an overall reduction of efficacy when the drug is used in combination with a bactericidal drug. Our goal here was to investigate this hypothesis systematically. We first constructed time-kill curves using five different antibiotics at clinically relevant concentrations, and we observed antagonism between bactericidal and bacteriostatic drugs. We extended our investigation by performing a screen of pairwise combinations of 21 different antibiotics at subinhibitory concentrations, and we found that strong antagonistic interactions were enriched significantly among combinations of bacteriostatic and bactericidal drugs. Finally, since our hypothesis relies on phenotypic effects produced by different drug classes, we recreated these experiments in a microfluidic device and performed time-lapse microscopy to directly observe and quantify the growth and division of individual cells with controlled antibiotic concentrations. While our single-cell observations supported the antagonism between bacteriostatic and bactericidal drugs, they revealed an unexpected variety of cellular responses to antagonistic drug combinations, suggesting that multiple mechanisms underlie the interactions. PMID:24867991

Neurotoxicity induced by methamphetamine-heroin combination in PC12 cells.

PubMed

Tian, Xiang; Ru, Qin; Xiong, Qi; Yue, Kai; Chen, Lin; Ma, Baomiao; Gan, Weimin; Si, Yuanren; Xiao, Huqiao; Li, Chaoying

2017-04-24

Simultaneous administration of psychostimulants and opioids is a major drug abuse problem worldwide. The combination of psychostimulants and opioids produces more serious effects than either drug alone and is responsible for numerous deaths. In recent years, owing to its increased use, methamphetamine (METH), a psychostimulant, has become a popular choice for use in combination with opioids, especially heroin. However, little is known about the neurotoxicity of METH/heroin combination. The aims of this study were to evaluate whether METH/heroin combination was more neurotoxic than either drug alone and analyze the possible neurotoxic mechanisms using rat pheochromocytoma (PC12) cells. Our data showed that METH/heroin combination exhibited a significant decrease in cell viability than either drug alone, and the coefficient of drug interaction (CDI) indicated that the combination appeared to produce synergistic effects. Further studies showed that METH/heroin combination induced apoptosis and decreased the mitochondrial potential significantly, compared to either drug alone. This was demonstrated by a significant decrease in the expression of Bcl-2 and an increase in expression of Bax, accompanied by increase in the activities of caspase-3 and caspase-9. These results suggest that the combination of METH and heroin is more neurotoxic than either drug alone, and it induces apoptosis via the mitochondrial apoptotic pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

SynergyFinder: a web application for analyzing drug combination dose-response matrix data.

PubMed

Ianevski, Aleksandr; He, Liye; Aittokallio, Tero; Tang, Jing

2017-08-01

Rational design of drug combinations has become a promising strategy to tackle the drug sensitivity and resistance problem in cancer treatment. To systematically evaluate the pre-clinical significance of pairwise drug combinations, functional screening assays that probe combination effects in a dose-response matrix assay are commonly used. To facilitate the analysis of such drug combination experiments, we implemented a web application that uses key functions of R-package SynergyFinder, and provides not only the flexibility of using multiple synergy scoring models, but also a user-friendly interface for visualizing the drug combination landscapes in an interactive manner. The SynergyFinder web application is freely accessible at https://synergyfinder.fimm.fi ; The R-package and its source-code are freely available at http://bioconductor.org/packages/release/bioc/html/synergyfinder.html . jing.tang@helsinki.fi. © The Author(s) 2017. Published by Oxford University Press.

Two drugs are better than one. A short history of combined therapy of ovarian cancer.

PubMed

Bukowska, Barbara; Gajek, Arkadiusz; Marczak, Agnieszka

2015-01-01

Combined therapy of ovarian cancer has a long history. It has been applied for many years. The first drug which was commonly combined with other chemotherapeutics was cisplatin. It turned out to be effective given together with alkylating agents as well as with taxanes. Another drug which is often the basis of first-line therapy is doxorubicin. The use of traditional chemotherapy is often limited due to side effects. This is why new drugs, targeted specifically at cancer cells (e.g. monoclonal antibodies or epidermal growth factor receptor inhibitors), offer a welcome addition when used in combination with conventional anticancer agents. Drugs applied in combination should be synergistic or at least additive. To evaluate the type of interaction between drugs in a plausible sequence, isobolographic analysis is used. This method allows one to assess whether the two agents could make an efficient combination, which might improve the therapy of ovarian cancer.

Longitudinal medical records as a complement to routine drug safety signal analysis†

PubMed Central

Watson, Sarah; Sandberg, Lovisa; Johansson, Jeanette; Edwards, I. Ralph

2015-01-01

Abstract Purpose To explore whether and how longitudinal medical records could be used as a source of reference in the early phases of signal detection and analysis of novel adverse drug reactions (ADRs) in a global pharmacovigilance database. Methods Drug and ADR combinations from the routine signal detection process of VigiBase® in 2011 were matched to combinations in The Health Improvement Network (THIN). The number and type of drugs and ADRs from the data sets were investigated. For unlabelled combinations, graphical display of longitudinal event patterns (chronographs) in THIN was inspected to determine if the pattern supported the VigiBase combination. Results Of 458 combinations in the VigiBase data set, 190 matched to corresponding combinations in THIN (after excluding drugs with less than 100 prescriptions in THIN). Eighteen percent of the VigiBase and 9% of the matched THIN combinations referred to new drugs reported with serious reactions. Of the 112 unlabelled combinations matched to THIN, 52 chronographs were inconclusive mainly because of lack of data; 34 lacked any outstanding pattern around the time of prescription; 24 had an elevation of events in the pre‐prescription period, hence weakened the suspicion of a drug relationship; two had an elevated pattern of events exclusively in the post‐prescription period that, after review of individual patient histories, did not support an association. Conclusions Longitudinal medical records were useful in understanding the clinical context around a drug and suspected ADR combination and the probability of a causal relationship. A drawback was the paucity of data for newly marketed drugs with serious reactions. © 2015 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd. PMID:25623045

An enhanced Petri-net model to predict synergistic effects of pairwise drug combinations from gene microarray data.

PubMed

Jin, Guangxu; Zhao, Hong; Zhou, Xiaobo; Wong, Stephen T C

2011-07-01

Prediction of synergistic effects of drug combinations has traditionally been relied on phenotypic response data. However, such methods cannot be used to identify molecular signaling mechanisms of synergistic drug combinations. In this article, we propose an enhanced Petri-Net (EPN) model to recognize the synergistic effects of drug combinations from the molecular response profiles, i.e. drug-treated microarray data. We addressed the downstream signaling network of the targets for the two individual drugs used in the pairwise combinations and applied EPN to the identified targeted signaling network. In EPN, drugs and signaling molecules are assigned to different types of places, while drug doses and molecular expressions are denoted by color tokens. The changes of molecular expressions caused by treatments of drugs are simulated by two actions of EPN: firing and blasting. Firing is to transit the drug and molecule tokens from one node or place to another, and blasting is to reduce the number of molecule tokens by drug tokens in a molecule node. The goal of EPN is to mediate the state characterized by control condition without any treatment to that of treatment and to depict the drug effects on molecules by the drug tokens. We applied EPN to our generated pairwise drug combination microarray data. The synergistic predictions using EPN are consistent with those predicted using phenotypic response data. The molecules responsible for the synergistic effects with their associated feedback loops display the mechanisms of synergism. The software implemented in Python 2.7 programming language is available from request. stwong@tmhs.org.

Preclinical optimization of a broad-spectrum anti-bladder cancer tri-drug regimen via the Feedback System Control (FSC) platform

NASA Astrophysics Data System (ADS)

Liu, Qi; Zhang, Cheng; Ding, Xianting; Deng, Hui; Zhang, Daming; Cui, Wei; Xu, Hongwei; Wang, Yingwei; Xu, Wanhai; Lv, Lei; Zhang, Hongyu; He, Yinghua; Wu, Qiong; Szyf, Moshe; Ho, Chih-Ming; Zhu, Jingde

2015-06-01

Therapeutic outcomes of combination chemotherapy have not significantly advanced during the past decades. This has been attributed to the formidable challenges of optimizing drug combinations. Testing a matrix of all possible combinations of doses and agents in a single cell line is unfeasible due to the virtually infinite number of possibilities. We utilized the Feedback System Control (FSC) platform, a phenotype oriented approach to test 100 options among 15,625 possible combinations in four rounds of assaying to identify an optimal tri-drug combination in eight distinct chemoresistant bladder cancer cell lines. This combination killed between 82.86% and 99.52% of BCa cells, but only 47.47% of the immortalized benign bladder epithelial cells. Preclinical in vivo verification revealed its markedly enhanced anti-tumor efficacy as compared to its bi- or mono-drug components in cell line-derived tumor xenografts. The collective response of these pathways to component drugs was both cell type- and drug type specific. However, the entire spectrum of pathways triggered by the tri-drug regimen was similar in all four cancer cell lines, explaining its broad spectrum killing of BCa lines, which did not occur with its component drugs. Our findings here suggest that the FSC platform holdspromise for optimization of anti-cancer combination chemotherapy.

Comparison of essential drug list in a rural secondary care hospital in south India with Indian & World Health Organization list 2011.

PubMed

Rao, Seetharama G; Thomas, Dixon; Zachariah, Seeba; Kannan, M S; Alvarez-Uria, Gerardo

2012-01-01

Fixed drug combinations are a major marketing strategy in India but it can compromise the rational use of medicines. In this study we compared the fixed drug combinations and dosage forms in the hospital pharmacy before and after introducing the essential drug list. We also compared the Hospital Essential Drug List (HEDL) 2011 with the World Health Organization (WHO) Essential Drug List (EDL) 2011 and the National Essential Drug List of India (NEDL) 2011. The study was done in a secondary level care charity hospital at Anantapur, AP with a bed size of 315 and an average OP per day of 1200-1700 visits. We compared the three essential drug lists (HEDL, WHOEDL and NEDL) and the hospital drug list before introducing EDL. Drugs which were present in NEDL and not present in the HEDL were also screened. Microsoft excel was used to tabulate the results and for graphs. The number of medicines used in the hospital before and after the introduction of the HEDL was 1627 and 424 respectively. On comparison, WHOEDL 2011 have 350 and NEDL of India have 348 medicines. While preparing the HEDL, 46 double drug combinations decreased to 15 and 9 triple drug combinations decreased to 1. In the case of injections, 20 double drug combinations decreased to 6 and 1 triple drug combination increased to 2. The number of tablets, capsules, injections, syrups, powders and inhalers was reduced to almost half. The great reductions were in 51 ointments to 9, 69 drops to 5, 11 paste to 0, 21 solutions to 3 and 14 creams to 1. The dosage forms removed included elixirs, insulin pens, gums, paste, paints, gargles and mouthwashes. There was drastic reduction in the number of medicines and dosage forms when the HEDL was implemented. Many of the fixed drug combinations were also removed for improving the rational use of medicines. The WHO essential drug list 2011, national essential drug list of India 2011 and the hospital essential drug list 2011 were comparable with few exceptions.

78 FR 75570 - Guidance for Industry on New Animal Drugs and New Animal Drug Combination Products Administered...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-12

... Medicated Feed or Drinking Water of Food-Producing Animals: Recommendations for Drug Sponsors for Voluntarily Aligning Product Use Conditions With Guidance for Industry 209; Availability AGENCY: Food and Drug... availability of a guidance for industry 213 entitled ``New Animal Drugs and New Animal Drug Combination...

The application of prodrug-based nano-drug delivery strategy in cancer combination therapy.

PubMed

Ge, Yanxiu; Ma, Yakun; Li, Lingbing

2016-10-01

Single drug therapy that leads to the multidrug resistance of cancer cells and severe side-effect is a thing of the past. Combination therapies that affect multiple signaling pathways have been the focus of recent active research. Due to the successful development of prodrug-based nano-drug delivery systems (P-N-DDSs), their use has been extended to combination therapy as drug delivery platforms. In this review, we focus specifically on the P-N-DDSs in the field of combination therapy including the combinations of prodrugs with different chemotherapeutic agents, other therapeutic agents, nucleic acid or the combination of different types of therapy (e.g. chemotherapy and phototherapy). The relevant examples of prodrug-based nanoparticulate drug delivery strategy in combination cancer therapy from the recent literature are discussed to demonstrate the feasibilities of relevant technology. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of Combination High-Throughput Phenotypic Screening and Target Identification Methods for the Discovery of Natural Product-Based Combination Drugs.

PubMed

Isgut, Monica; Rao, Mukkavilli; Yang, Chunhua; Subrahmanyam, Vangala; Rida, Padmashree C G; Aneja, Ritu

2018-03-01

Modern drug discovery efforts have had mediocre success rates with increasing developmental costs, and this has encouraged pharmaceutical scientists to seek innovative approaches. Recently with the rise of the fields of systems biology and metabolomics, network pharmacology (NP) has begun to emerge as a new paradigm in drug discovery, with a focus on multiple targets and drug combinations for treating disease. Studies on the benefits of drug combinations lay the groundwork for a renewed focus on natural products in drug discovery. Natural products consist of a multitude of constituents that can act on a variety of targets in the body to induce pharmacodynamic responses that may together culminate in an additive or synergistic therapeutic effect. Although natural products cannot be patented, they can be used as starting points in the discovery of potent combination therapeutics. The optimal mix of bioactive ingredients in natural products can be determined via phenotypic screening. The targets and molecular mechanisms of action of these active ingredients can then be determined using chemical proteomics, and by implementing a reverse pharmacokinetics approach. This review article provides evidence supporting the potential benefits of natural product-based combination drugs, and summarizes drug discovery methods that can be applied to this class of drugs. © 2017 Wiley Periodicals, Inc.

21 CFR 610.17 - Permissible combinations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Permissible combinations. 610.17 Section 610.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS GENERAL BIOLOGICAL PRODUCTS STANDARDS General Provisions § 610.17 Permissible combinations...

Closed-loop control of cellular functions using combinatory drugs guided by a stochastic search algorithm

PubMed Central

Wong, Pak Kin; Yu, Fuqu; Shahangian, Arash; Cheng, Genhong; Sun, Ren; Ho, Chih-Ming

2008-01-01

A mixture of drugs is often more effective than using a single effector. However, it is extremely challenging to identify potent drug combinations by trial and error because of the large number of possible combinations and the inherent complexity of the underlying biological network. With a closed-loop optimization modality, we experimentally demonstrate effective searching for potent drug combinations for controlling cellular functions through a large parametric space. Only tens of iterations out of one hundred thousand possible trials were needed to determine a potent combination of drugs for inhibiting vesicular stomatitis virus infection of NIH 3T3 fibroblasts. In addition, the drug combination reduced the required dosage by ≈10-fold compared with individual drugs. In another example, a potent mixture was identified in thirty iterations out of a possible million combinations of six cytokines that regulate the activity of nuclear factor kappa B in 293T cells. The closed-loop optimization approach possesses the potential of being an effective approach for manipulating a wide class of biological systems. PMID:18356295

Efficacy and safety of a four-drug fixed-dose combination regimen versus separate drugs for treatment of pulmonary tuberculosis: a systematic review and meta-analysis.

PubMed

Lima, Glaura C; Silva, Emilia V; Magalhães, Pérola de O; Naves, Janeth S

Tuberculosis, particularly multi-drug-resistant tuberculosis, is a major cause of morbidity and mortality worldwide. To the best of our knowledge, however, no study to date has assessed the combined use of the four available drugs for tuberculosis treatment, which is an issue of great clinical relevance. To determine whether the four-drug fixed-dose combination is safer or more effective than separate drugs for treatment of pulmonary tuberculosis. A systematic review of the literature was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In pooled results from five randomized controlled trials with 3502 patients across Africa, Asia, and Latin America, four-drug fixed-dose combination therapy was no better than separate drugs therapy in terms of culture conversion after 2 and 6 months of treatment. There were no significant differences between the groups in overall incidence of adverse effects. However, the meta-analytic measure (log odds ratio) revealed that separate drugs treatment had a 1.65 [exp (0.5)=1.65] increased chance of gastrointestinal adverse effects compared to four-drug fixed-dose combination treatment. The reviewed studies showed that four-drug fixed-dose combination therapy provides greater patient comfort by reducing the number of pills and the incidence of gastrointestinal adverse effects, as well as simplifying pharmaceutical management at all levels. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Selective Targeting of CTNNB1-, KRAS- or MYC-Driven Cell Growth by Combinations of Existing Drugs

PubMed Central

Uitdehaag, Joost C. M.; de Roos, Jeroen A. D. M.; van Doornmalen, Antoon M.; Prinsen, Martine B. W.; Spijkers-Hagelstein, Jill A. P.; de Vetter, Judith R. F.; de Man, Jos; Buijsman, Rogier C.; Zaman, Guido J. R.

2015-01-01

The aim of combination drug treatment in cancer therapy is to improve response rate and to decrease the probability of the development of drug resistance. Preferably, drug combinations are synergistic rather than additive, and, ideally, drug combinations work synergistically only in cancer cells and not in non-malignant cells. We have developed a workflow to identify such targeted synergies, and applied this approach to selectively inhibit the proliferation of cell lines with mutations in genes that are difficult to modulate with small molecules. The approach is based on curve shift analysis, which we demonstrate is a more robust method of determining synergy than combination matrix screening with Bliss-scoring. We show that the MEK inhibitor trametinib is more synergistic in combination with the BRAF inhibitor dabrafenib than with vemurafenib, another BRAF inhibitor. In addition, we show that the combination of MEK and BRAF inhibitors is synergistic in BRAF-mutant melanoma cells, and additive or antagonistic in, respectively, BRAF-wild type melanoma cells and non-malignant fibroblasts. This combination exemplifies that synergistic action of drugs can depend on cancer genotype. Next, we used curve shift analysis to identify new drug combinations that specifically inhibit cancer cell proliferation driven by difficult-to-drug cancer genes. Combination studies were performed with compounds that as single agents showed preference for inhibition of cancer cells with mutations in either the CTNNB1 gene (coding for β-catenin), KRAS, or cancer cells expressing increased copy numbers of MYC. We demonstrate that the Wnt-pathway inhibitor ICG-001 and trametinib acted synergistically in Wnt-pathway-mutant cell lines. The ERBB2 inhibitor TAK-165 was synergistic with trametinib in KRAS-mutant cell lines. The EGFR/ERBB2 inhibitor neratinib acted synergistically with the spindle poison docetaxel and with the Aurora kinase inhibitor GSK-1070916 in cell lines with MYC amplification. Our approach can therefore efficiently discover novel drug combinations that selectively target cancer genes. PMID:26018524

An Application of Fractional Factorial Designs to Study Drug Combinations

PubMed Central

Jaynes, Jessica; Ding, Xianting; Xu, Hongquan; Wong, Weng Kee; Ho, Chih-Ming

2013-01-01

Herpes simplex virus type 1 (HSV-1) is known to cause diseases of various severities. There is increasing interest to find drug combinations to treat HSV-1 by reducing drug resistance and cytotoxicity. Drug combinations offer potentially higher efficacy and lower individual drug dosage. In this paper, we report a new application of fractional factorial designs to investigate a biological system with HSV-1 and six antiviral drugs, namely, Interferon-alpha, Interferon-beta, Interferon-gamma, Ribavirin, Acyclovir, and TNF-alpha. We show how the sequential use of two- and three-level fractional factorial designs can screen for important drugs and drug interactions, as well as determine potential optimal drug dosages through the use of contour plots. Our initial experiment using a two-level fractional factorial design suggests that there is model inadequacy and drug dosages should be reduced. A follow-up experiment using a blocked three-level fractional factorial design indicates that TNF-alpha has little effect and HSV-1 infection can be suppressed effectively by using a right combination of the other five antiviral drugs. These observations have practical implications in the understanding of antiviral drug mechanism that can result in better design of antiviral drug therapy. PMID:22859316

Two drugs are better than one. A short history of combined therapy of ovarian cancer

PubMed Central

Gajek, Arkadiusz; Marczak, Agnieszka

2014-01-01

Combined therapy of ovarian cancer has a long history. It has been applied for many years. The first drug which was commonly combined with other chemotherapeutics was cisplatin. It turned out to be effective given together with alkylating agents as well as with taxanes. Another drug which is often the basis of first-line therapy is doxorubicin. The use of traditional chemotherapy is often limited due to side effects. This is why new drugs, targeted specifically at cancer cells (e.g. monoclonal antibodies or epidermal growth factor receptor inhibitors), offer a welcome addition when used in combination with conventional anticancer agents. Drugs applied in combination should be synergistic or at least additive. To evaluate the type of interaction between drugs in a plausible sequence, isobolographic analysis is used. This method allows one to assess whether the two agents could make an efficient combination, which might improve the therapy of ovarian cancer. PMID:26793017

The application of drug dose equivalence in the quantitative analysis of receptor occupation and drug combinations

PubMed Central

Tallarida, Ronald J.; Raffa, Robert B.

2014-01-01

In this review we show that the concept of dose equivalence for two drugs, the theoretical basis of the isobologram, has a wider use in the analysis of pharmacological data derived from single and combination drug use. In both its application to drug combination analysis with isoboles and certain other actions, listed below, the determination of doses, or receptor occupancies, that yield equal effects provide useful metrics that can be used to obtain quantitative information on drug actions without postulating any intimate mechanism of action. These other drug actions discussed here include (1) combinations of agonists that produce opposite effects, (2) analysis of inverted U-shaped dose effect curves of single agents, (3) analysis on the effect scale as an alternative to isoboles and (4) the use of occupation isoboles to examine competitive antagonism in the dual receptor case. New formulas derived to assess the statistical variance for additive combinations are included, and the more detailed mathematical topics are included in the appendix. PMID:20546783

Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance.

PubMed

Khdair, Ayman; Chen, Di; Patil, Yogesh; Ma, Linan; Dou, Q Ping; Shekhar, Malathy P V; Panyam, Jayanth

2010-01-25

Tumor drug resistance significantly limits the success of chemotherapy in the clinic. Tumor cells utilize multiple mechanisms to prevent the accumulation of anticancer drugs at their intracellular site of action. In this study, we investigated the anticancer efficacy of doxorubicin in combination with photodynamic therapy using methylene blue in a drug-resistant mouse tumor model. Surfactant-polymer hybrid nanoparticles formulated using an anionic surfactant, Aerosol-OT (AOT), and a naturally occurring polysaccharide polymer, sodium alginate, were used for synchronized delivery of the two drugs. Balb/c mice bearing syngeneic JC tumors (mammary adenocarcinoma) were used as a drug-resistant tumor model. Nanoparticle-mediated combination therapy significantly inhibited tumor growth and improved animal survival. Nanoparticle-mediated combination treatment resulted in enhanced tumor accumulation of both doxorubicin and methylene blue, significant inhibition of tumor cell proliferation, and increased induction of apoptosis. These data suggest that nanoparticle-mediated combination chemotherapy and photodynamic therapy using doxorubicin and methylene blue has significant therapeutic potential against drug-resistant tumors. Copyright 2009 Elsevier B.V. All rights reserved.

Drug Delivery Systems and Combination Therapy by Using Vinca Alkaloids

PubMed Central

Lee, Chun-Ting; Huang, Yen-Wei; Yang, Chih-Hui; Huang, Keng-Shiang

2015-01-01

Developing new methods for chemotherapy drug delivery has become a topic of great concern. Vinca alkaloids are among the most widely used chemotherapy reagents for tumor therapy; however, their side effects are particularly problematic for many medical doctors. To reduce the toxicity and enhance the therapeutic efficiency of vinca alkaloids, many researchers have developed strategies such as using liposome-entrapped drugs, chemical- or peptide-modified drugs, polymeric packaging drugs, and chemotherapy drug combinations. This review mainly focuses on the development of a vinca alkaloid drug delivery system and the combination therapy. Five vinca alkaloids (eg, vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) are reviewed. PMID:25877096

Tolerability of continuous subcutaneous octreotide used in combination with other drugs.

PubMed

Mercadante, S

1995-01-01

Continuous subcutaneous infusion of octreotide combined with other drugs has proved to be useful in some circumstances in palliative care setting when theoral route is no longer available. Forty-four patients were administered octreotide alone or in combination with other drugs in the same syringe driver for symptom control in advanced cancer patients. Good tolerability and compatibility were observed without visual drug precipitation for a period of 48 hours at room temperature, the standard clinical situation in patients' homes. Such a combination of drugs administered by the subcutaneous route makes possible the adequate control of symptoms in the final days of life.

Evaluation of trypanocidal activity of combinations of anti-sleeping sickness drugs with cysteine protease inhibitors.

PubMed

Steverding, Dietmar

2015-01-01

Chemotherapy of human African trypanosomiasis (HAT) is unsatisfactory because only a few drugs, with serious side effects and poor efficacy, are available. As drug combination regimes often achieve greater therapeutic efficacy than monotherapies, here the trypanocidal activity of the cysteine protease inhibitor K11777 in combination with current anti-HAT drugs using bloodstream forms of Trypanosoma brucei was investigated. Isobolographic analysis was used to determine the interaction between cysteine protease inhibitors (K11777, CA-074Me and CAA0225) and anti-HAT drugs (suramin, pentamidine, melarsoprol and eflornithine). Bloodstream forms of T. brucei were incubated in culture medium containing cysteine protease inhibitors or anti-HAT drugs alone or in combination at a 1:1 fixed-dose ratio. After 48 h incubation, live cells were counted, the 50% growth inhibition values determined and combination indices calculated. The general cytotoxicity of drug combinations was evaluated with human leukaemia HL-60 cells. Combinations of K11777 with suramin, pentamidine and melarsoprol showed antagonistic effects while with eflornithine a synergistic effect was observed. Whereas eflornithine antagonises with CA-074Me, an inhibitor inactivating the targeted TbCATL only under reducing conditions, it synergises with CAA0255, an inhibitor structurally related to CA-074Me which inactivates TbCATL independently of thiols. These findings indicate an essential role of thiols for the synergistic interaction between K11777 and eflornithine. Encouragingly, the K11777/eflornithine combination displayed higher trypanocidal than cytotoxic activity. The results of this study suggest that the combination of the cysteine protease inhibitor K11777 and eflornithine display promising synergistic trypanocidal activity that warrants further investigation of the drug combination as possible alternative treatment of HAT. Copyright © 2015 Elsevier Inc. All rights reserved.

Patient-Customized Drug Combination Prediction and Testing for T-cell Prolymphocytic Leukemia Patients.

PubMed

He, Liye; Tang, Jing; Andersson, Emma I; Timonen, Sanna; Koschmieder, Steffen; Wennerberg, Krister; Mustjoki, Satu; Aittokallio, Tero

2018-05-01

The molecular pathways that drive cancer progression and treatment resistance are highly redundant and variable between individual patients with the same cancer type. To tackle this complex rewiring of pathway cross-talk, personalized combination treatments targeting multiple cancer growth and survival pathways are required. Here we implemented a computational-experimental drug combination prediction and testing (DCPT) platform for efficient in silico prioritization and ex vivo testing in patient-derived samples to identify customized synergistic combinations for individual cancer patients. DCPT used drug-target interaction networks to traverse the massive combinatorial search spaces among 218 compounds (a total of 23,653 pairwise combinations) and identified cancer-selective synergies by using differential single-compound sensitivity profiles between patient cells and healthy controls, hence reducing the likelihood of toxic combination effects. A polypharmacology-based machine learning modeling and network visualization made use of baseline genomic and molecular profiles to guide patient-specific combination testing and clinical translation phases. Using T-cell prolymphocytic leukemia (T-PLL) as a first case study, we show how the DCPT platform successfully predicted distinct synergistic combinations for each of the three T-PLL patients, each presenting with different resistance patterns and synergy mechanisms. In total, 10 of 24 (42%) of selective combination predictions were experimentally confirmed to show synergy in patient-derived samples ex vivo The identified selective synergies among approved drugs, including tacrolimus and temsirolimus combined with BCL-2 inhibitor venetoclax, may offer novel drug repurposing opportunities for treating T-PLL. Significance: An integrated use of functional drug screening combined with genomic and molecular profiling enables patient-customized prediction and testing of drug combination synergies for T-PLL patients. Cancer Res; 78(9); 2407-18. ©2018 AACR . ©2018 American Association for Cancer Research.

Opportunities and Challenges for Niosomes as Drug Delivery Systems.

PubMed

Thakkar, Miloni; Brijesh, S

2016-01-01

With the increase in drug resistance observed in most infectious diseases as well as some forms of cancer, and with the chances of development of new drug molecules to address this issue looking bleak, one of the most plausible ways to disease treatment is combination therapy. Combination therapy would ensure delay in drug resistance, if utilized rationally. However, the biggest difficulty in employing combination therapy are adverse effects due to potential drug-drug interactions and patient compliance due to multiple routes of administration or multiple dosing that may be required. To overcome these issues, researchers have utilized nanoparticle-based systems that can hold multiple drugs in a single carrier. There are several nanocarrier systems available for such purposes. However, the focus of this review will be non-ionic surfactant-based systems (niosomes) for delivery of multiple therapeutic agents. Niosomes are artificially prepared drug delivery carriers. They are structurally similar to liposomes albeit more stable than them. Literature pertaining to combination drug delivery and various drug delivery systems was reviewed. It was conceptualized that many of the methods used to prepare various types of carriers for combination delivery of drugs may be used for niosomal systems as well. We envisage that niosomes may effectively be utilized to package older drugs in newer ways. The review will thus focus on techniques that may be used for the formulation of niosomes, ways to encapsulate multiple-drug moieties, and challenges associated in preparing and optimizing such systems.

Activity of Oxantel Pamoate Monotherapy and Combination Chemotherapy against Trichuris muris and Hookworms: Revival of an Old Drug

PubMed Central

Keiser, Jennifer; Tritten, Lucienne; Silbereisen, Angelika; Speich, Benjamin; Adelfio, Roberto; Vargas, Mireille

2013-01-01

Background It is widely recognized that only a handful of drugs are available against soil-transmitted helminthiasis, all of which are characterized by a low efficacy against Trichuris trichiura, when administered as single doses. The re-evaluation of old, forgotten drugs is a promising strategy to identify alternative anthelminthic drug candidates or drug combinations. Methodology We studied the activity of the veterinary drug oxantel pamoate against Trichuris muris, Ancylostoma ceylanicum and Necator americanus in vitro and in vivo. In addition, the dose-effect of oxantel pamoate combined with albendazole, mebendazole, levamisole, pyrantel pamoate and ivermectin was studied against T. muris in vitro and additive or synergistic combinations were followed up in vivo. Principal Findings We calculated an ED50 of 4.7 mg/kg for oxantel pamoate against T. muris in mice. Combinations of oxantel pamoate with pyrantel pamoate behaved antagonistically in vitro (combination index (CI) = 2.53). Oxantel pamoate combined with levamisole, albendazole or ivermectin using ratios based on their ED50s revealed antagonistic effects in vivo (CI = 1.27, 1.90 and 1.27, respectively). A highly synergistic effect (CI = 0.15) was observed when oxantel pamoate-mebendazole was administered to T. muris-infected mice. Oxantel pamoate (10 mg/kg) lacked activity against Ancylostoma ceylanicum and Necator americanus in vivo. Conclusion/Significance Our study confirms the excellent trichuricidal properties of oxantel pamoate. Since the drug lacks activity against hookworms it is necessary to combine oxantel pamoate with a partner drug with anti-hookworm properties. Synergistic effects were observed for oxantel pamoate-mebendazole, hence this combination should be studied in more detail. Since, of the standard drugs, albendazole has the highest efficacy against hookworms, additional investigations on the combination effect of oxantel pamoate-albendazole should be launched. PMID:23556013

Fast dissolving drug-drug eutectics with improved compressibility and synergistic effects.

PubMed

Thipparaboina, Rajesh; Thumuri, Dinesh; Chavan, Rahul; Naidu, V G M; Shastri, Nalini R

2017-06-15

Combinational therapy has become increasingly popular in recent times due to various advantages like greater therapeutic effect, reduced number of prescriptions, lower administrative costs, and an increase in patient compliance. Drug-drug multicomponent adducts could help in combination of drugs at supramolecular level. Two drug-drug eutectics of etodolac with paracetamol (EP) and etodolac with propranolol hydrochloride (EPHC) were successfully designed and synthesized for the first time. These eutectics significantly improved dissolution and material properties. A 6 to 9 fold enhancement in % dissolution efficiency was found at 1min suggesting the fast dissolving capabilities of the eutectic mixtures when compared to plain drug. In addition, eutectic mixtures have shown improved hardness compared to plain drugs. EP and EPHC have shown around 5 fold and 3 fold improvements in hardness respectively at 10MPa when compared to plain etodolac. Cell culture studies have shown improved effects of EP. Western blotting analysis revealed that the said combination successfully reduced various inflammatory mediators like TNF-α, COX-2 and IL-6. Whereas, the eutectic combination EPHC has shown enhanced cytotoxic effects with synergistic combination index and favorable dose reduction index. The generated multi-component systems EP and EPHC with fast dissolving capabilities, improved hardness at lower pressures and synergistic effects represent prospective combinations for effective treatment of osteoarthritis and cancer chemotherapy respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

21 CFR 347.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... sections of the applicable OTC drug monographs. For a combination drug product that does not have an... combination, as established in the statement of identity sections of the applicable OTC drug monographs. (b... monographs, unless otherwise stated in this paragraph (b). Other truthful and nonmisleading statements...

21 CFR 347.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... sections of the applicable OTC drug monographs. For a combination drug product that does not have an... combination, as established in the statement of identity sections of the applicable OTC drug monographs. (b... monographs, unless otherwise stated in this paragraph (b). Other truthful and nonmisleading statements...

21 CFR 341.85 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... combination, as established in the statement of identity sections of the applicable OTC drug monographs. If... drug monographs, unless otherwise stated in this paragraph (a). (1) For permitted combinations... established in the indications sections of the applicable OTC drug monographs, unless otherwise stated in this...

21 CFR 346.22 - Permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Permitted combinations of anorectal active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANORECTAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 346.22 Permitted combinations of anorectal active ingredients. (a) Any two, three, or four...

21 CFR 346.22 - Permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Permitted combinations of anorectal active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANORECTAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 346.22 Permitted combinations of anorectal active ingredients. (a) Any two, three, or four...

21 CFR 346.22 - Permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Permitted combinations of anorectal active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANORECTAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 346.22 Permitted combinations of anorectal active ingredients. (a) Any two, three, or four...

21 CFR 341.85 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Labeling of permitted combinations of active ingredients. 341.85 Section 341.85 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE COLD, COUGH, ALLERGY, BRONCHODILATOR, AND ANTIASTHMATIC DRUG...

Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance in vitro.

PubMed

Khdair, Ayman; Handa, Hitesh; Mao, Guangzhao; Panyam, Jayanth

2009-02-01

Drug resistance limits the success of many anticancer drugs. Reduced accumulation of the drug at its intracellular site of action because of overexpression of efflux transporters such as P-glycoprotein (P-gp) is a major mechanism of drug resistance. In this study, we investigated whether photodynamic therapy (PDT) using methylene blue, also a P-gp inhibitor, can be used to enhance doxorubicin-induced cytotoxicity in drug-resistant tumor cells. Aerosol OT (AOT)-alginate nanoparticles were used as a carrier for the simultaneous cellular delivery of doxorubicin and methylene blue. Methylene blue was photoactivated using light of 665 nm wavelength. Induction of apoptosis and necrosis following treatment with combination chemotherapy and PDT was investigated in drug-resistant NCI/ADR-RES cells using flow cytometry and fluorescence microscopy. Effect of encapsulation in nanoparticles on the intracellular accumulation of doxorubicin and methylene blue was investigated qualitatively using fluorescence microscopy and was quantitated using HPLC. Encapsulation in AOT-alginate nanoparticles significantly enhanced the cytotoxicity of combination therapy in resistant tumor cells. Nanoparticle-mediated combination therapy resulted in a significant induction of both apoptosis and necrosis. Improvement in cytotoxicity could be correlated with enhanced intracellular and nuclear delivery of the two drugs. Further, nanoparticle-mediated combination therapy resulted in significantly elevated reactive oxygen species (ROS) production compared to single drug treatment. In conclusion, nanoparticle-mediated combination chemotherapy and PDT using doxorubicin and methylene blue was able to overcome resistance mechanisms and resulted in improved cytotoxicity in drug-resistant tumor cells.

Application of Feedback System Control Optimization Technique in Combined Use of Dual Antiplatelet Therapy and Herbal Medicines

PubMed Central

Liu, Wang; Li, Yu-Long; Feng, Mu-Ting; Zhao, Yu-Wei; Ding, Xianting; He, Ben; Liu, Xuan

2018-01-01

Aim: Combined use of herbal medicines in patients underwent dual antiplatelet therapy (DAPT) might cause bleeding or thrombosis because herbal medicines with anti-platelet activities may exhibit interactions with DAPT. In this study, we tried to use a feedback system control (FSC) optimization technique to optimize dose strategy and clarify possible interactions in combined use of DAPT and herbal medicines. Methods: Herbal medicines with reported anti-platelet activities were selected by searching related references in Pubmed. Experimental anti-platelet activities of representative compounds originated from these herbal medicines were investigated using in vitro assay, namely ADP-induced aggregation of rat platelet-rich-plasma. FSC scheme hybridized artificial intelligence calculation and bench experiments to iteratively optimize 4-drug combination and 2-drug combination from these drug candidates. Results: Totally 68 herbal medicines were reported to have anti-platelet activities. In the present study, 7 representative compounds from these herbal medicines were selected to study combinatorial drug optimization together with DAPT, i.e., aspirin and ticagrelor. FSC technique first down-selected 9 drug candidates to the most significant 5 drugs. Then, FSC further secured 4 drugs in the optimal combination, including aspirin, ticagrelor, ferulic acid from DangGui, and forskolin from MaoHouQiaoRuiHua. Finally, FSC quantitatively estimated the possible interactions between aspirin:ticagrelor, aspirin:ferulic acid, ticagrelor:forskolin, and ferulic acid:forskolin. The estimation was further verified by experimentally determined Combination Index (CI) values. Conclusion: Results of the present study suggested that FSC optimization technique could be used in optimization of anti-platelet drug combinations and might be helpful in designing personal anti-platelet therapy strategy. Furthermore, FSC analysis could also identify interactions between different drugs which might provide useful information for research of signal cascades in platelet. PMID:29780330

Advancing cancer drug discovery towards more agile development of targeted combination therapies.

PubMed

Carragher, Neil O; Unciti-Broceta, Asier; Cameron, David A

2012-01-01

Current drug-discovery strategies are typically 'target-centric' and are based upon high-throughput screening of large chemical libraries against nominated targets and a selection of lead compounds with optimized 'on-target' potency and selectivity profiles. However, high attrition of targeted agents in clinical development suggest that combinations of targeted agents will be most effective in treating solid tumors if the biological networks that permit cancer cells to subvert monotherapies are identified and retargeted. Conventional drug-discovery and development strategies are suboptimal for the rational design and development of novel drug combinations. In this article, we highlight a series of emerging technologies supporting a less reductionist, more agile, drug-discovery and development approach for the rational design, validation, prioritization and clinical development of novel drug combinations.

Output-driven feedback system control platform optimizes combinatorial therapy of tuberculosis using a macrophage cell culture model.

PubMed

Silva, Aleidy; Lee, Bai-Yu; Clemens, Daniel L; Kee, Theodore; Ding, Xianting; Ho, Chih-Ming; Horwitz, Marcus A

2016-04-12

Tuberculosis (TB) remains a major global public health problem, and improved treatments are needed to shorten duration of therapy, decrease disease burden, improve compliance, and combat emergence of drug resistance. Ideally, the most effective regimen would be identified by a systematic and comprehensive combinatorial search of large numbers of TB drugs. However, optimization of regimens by standard methods is challenging, especially as the number of drugs increases, because of the extremely large number of drug-dose combinations requiring testing. Herein, we used an optimization platform, feedback system control (FSC) methodology, to identify improved drug-dose combinations for TB treatment using a fluorescence-based human macrophage cell culture model of TB, in which macrophages are infected with isopropyl β-D-1-thiogalactopyranoside (IPTG)-inducible green fluorescent protein (GFP)-expressing Mycobacterium tuberculosis (Mtb). On the basis of only a single screening test and three iterations, we identified highly efficacious three- and four-drug combinations. To verify the efficacy of these combinations, we further evaluated them using a methodologically independent assay for intramacrophage killing of Mtb; the optimized combinations showed greater efficacy than the current standard TB drug regimen. Surprisingly, all top three- and four-drug optimized regimens included the third-line drug clofazimine, and none included the first-line drugs isoniazid and rifampin, which had insignificant or antagonistic impacts on efficacy. Because top regimens also did not include a fluoroquinolone or aminoglycoside, they are potentially of use for treating many cases of multidrug- and extensively drug-resistant TB. Our study shows the power of an FSC platform to identify promising previously unidentified drug-dose combinations for treatment of TB.

Randomized trials of high-dose chemotherapy in breast cancer: fraud, the press and the data (or lessons learned in medical policy governing clinical research).

PubMed Central

Antman, Karen

2002-01-01

High dose therapy for breast cancer remains controversial. Of the 15 randomized trials of high dose therapy in breast cancer reported to date, two South African studies have been discredited leaving 13 remaining studies. Mortality was consistently low, in the 0 to 2.5% range, except for the BCNU containing American Intergroup study, which had a 7.4% toxic mortality rate. Seven of the remaining 13 studies randomized fewer than 200 patients. Three of these small studies have significant differences in disease free survival, and a fourth study has a trend in favor of high dose therapy. The other three small studies cannot exclude a survival difference of 20%. Of the 6 remaining moderately large trials of 219 to 885 randomized patients, 5 are adjuvant studies and one included patients with metastatic disease. Of the five adjuvant trials, four have significant differences in relapse rate favoring the high dose arm, and the remaining study has a trend (with a high dose sequential single agent design rather than combination therapy as in the other studies). A planned subset analysis of the first 284 patients in the largest study funded by the Dutch insurance industry showed a significant advantage for high dose therapy. Given the 2-year median time to relapse and an addition 2-year median to death after relapse, the follow up for survival of 3-5 years on these studies is still short. In the only moderately sized metastatic trial from the National Cancer Institute of Canada with a very short median follow-up of 19 months, a significant difference in disease free survival has emerged, with no difference in survival. PMID:12053718

Randomized trials of high-dose chemotherapy in breast cancer: fraud, the press and the data (or lessons learned in medical policy governing clinical research).

PubMed

Antman, Karen

2002-01-01

High dose therapy for breast cancer remains controversial. Of the 15 randomized trials of high dose therapy in breast cancer reported to date, two South African studies have been discredited leaving 13 remaining studies. Mortality was consistently low, in the 0 to 2.5% range, except for the BCNU containing American Intergroup study, which had a 7.4% toxic mortality rate. Seven of the remaining 13 studies randomized fewer than 200 patients. Three of these small studies have significant differences in disease free survival, and a fourth study has a trend in favor of high dose therapy. The other three small studies cannot exclude a survival difference of 20%. Of the 6 remaining moderately large trials of 219 to 885 randomized patients, 5 are adjuvant studies and one included patients with metastatic disease. Of the five adjuvant trials, four have significant differences in relapse rate favoring the high dose arm, and the remaining study has a trend (with a high dose sequential single agent design rather than combination therapy as in the other studies). A planned subset analysis of the first 284 patients in the largest study funded by the Dutch insurance industry showed a significant advantage for high dose therapy. Given the 2-year median time to relapse and an addition 2-year median to death after relapse, the follow up for survival of 3-5 years on these studies is still short. In the only moderately sized metastatic trial from the National Cancer Institute of Canada with a very short median follow-up of 19 months, a significant difference in disease free survival has emerged, with no difference in survival.

Molecularly targeted drug combinations demonstrate selective effectiveness for myeloid- and lymphoid-derived hematologic malignancies

PubMed Central

Eide, Christopher A.; Kaempf, Andy; Khanna, Vishesh; Savage, Samantha L.; Rofelty, Angela; English, Isabel; Ho, Hibery; Pandya, Ravi; Bolosky, William J.; Poon, Hoifung; Deininger, Michael W.; Collins, Robert; Swords, Ronan T.; Watts, Justin; Pollyea, Daniel A.; Medeiros, Bruno C.; Traer, Elie; Tognon, Cristina E.; Mori, Motomi; Druker, Brian J.; Tyner, Jeffrey W.

2017-01-01

Translating the genetic and epigenetic heterogeneity underlying human cancers into therapeutic strategies is an ongoing challenge. Large-scale sequencing efforts have uncovered a spectrum of mutations in many hematologic malignancies, including acute myeloid leukemia (AML), suggesting that combinations of agents will be required to treat these diseases effectively. Combinatorial approaches will also be critical for combating the emergence of genetically heterogeneous subclones, rescue signals in the microenvironment, and tumor-intrinsic feedback pathways that all contribute to disease relapse. To identify novel and effective drug combinations, we performed ex vivo sensitivity profiling of 122 primary patient samples from a variety of hematologic malignancies against a panel of 48 drug combinations. The combinations were designed as drug pairs that target nonoverlapping biological pathways and comprise drugs from different classes, preferably with Food and Drug Administration approval. A combination ratio (CR) was derived for each drug pair, and CRs were evaluated with respect to diagnostic categories as well as against genetic, cytogenetic, and cellular phenotypes of specimens from the two largest disease categories: AML and chronic lymphocytic leukemia (CLL). Nearly all tested combinations involving a BCL2 inhibitor showed additional benefit in patients with myeloid malignancies, whereas select combinations involving PI3K, CSF1R, or bromodomain inhibitors showed preferential benefit in lymphoid malignancies. Expanded analyses of patients with AML and CLL revealed specific patterns of ex vivo drug combination efficacy that were associated with select genetic, cytogenetic, and phenotypic disease subsets, warranting further evaluation. These findings highlight the heuristic value of an integrated functional genomic approach to the identification of novel treatment strategies for hematologic malignancies. PMID:28784769

Local Infiltration of Analgesics at Surgical Wound to Reduce Postoperative Pain After Laparotomy in Rats.

PubMed

Kroin, Jeffrey S; Li, Jinyuan; Moric, Mario; Birmingham, Brian W; Tuman, Kenneth J; Buvanendran, Asokumar

There is an increasing use of local infiltration analgesia (LIA) to reduce postoperative pain. Despite widespread use of LIA, wide variations in drug combinations and concomitant use of systemic analgesics have made it difficult to determine the optimal drug combinations for LIA. Using a previously validated rat laparotomy model, the optimal LIA combination of medications to reduce postoperative pain was determined. Laparotomy was performed in an adult rat model under isoflurane anesthesia. During surgery, combinations of bupivacaine, ketorolac, and dexamethasone were injected over the sutured muscle wound before skin closing, and compared to saline (placebo). The same medications were injected systemically as controls. Postoperative pain was assessed by measuring spontaneous rearing activity. A high-dose 3-drug LIA combination (50 μL of bupivacaine 0.75%, ketorolac 6.0 mg/mL, and dexamethasone 2.0 mg/mL) increased rearing (decreased pain) at 2 hours (P = 0.0032) postsurgery compared to saline. However, the same 3 drugs injected systemically had a similar analgesic effect (P = 0.0002). Bupivacaine 0.75% alone was not effective for LIA. When low-dose (9-fold reduction) 3-drug LIA combination was used, LIA increased rearing (P = 0.0034) whereas the same 3 drugs injected systemically had no effect. Low-dose LIA ketorolac/dexamethasone (2-drug combination) also increased rearing (P = 0.0393). Our animal study suggests that clinical trials with low-dose LIA combinations of local anesthetic, nonsteroidal anti-inflammatory drug, and corticosteroid may be useful for reducing postoperative pain after laparotomy.

21 CFR 352.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of permitted combinations of active ingredients. 352.60 Section 352.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... INDEFINITELY] Labeling § 352.60 Labeling of permitted combinations of active ingredients. Statements of...

21 CFR 349.79 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Labeling of permitted combinations of active ingredients. 349.79 Section 349.79 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... § 349.79 Labeling of permitted combinations of active ingredients. Statements of identity, indications...

21 CFR 352.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of permitted combinations of active ingredients. 352.60 Section 352.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... INDEFINITELY] Labeling § 352.60 Labeling of permitted combinations of active ingredients. Statements of...

21 CFR 346.52 - Labeling of permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of permitted combinations of anorectal active ingredients. 346.52 Section 346.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... HUMAN USE Labeling § 346.52 Labeling of permitted combinations of anorectal active ingredients...

21 CFR 349.79 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Labeling of permitted combinations of active ingredients. 349.79 Section 349.79 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... § 349.79 Labeling of permitted combinations of active ingredients. Statements of identity, indications...

21 CFR 349.79 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of permitted combinations of active ingredients. 349.79 Section 349.79 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... § 349.79 Labeling of permitted combinations of active ingredients. Statements of identity, indications...

21 CFR 352.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of permitted combinations of active ingredients. 352.60 Section 352.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... INDEFINITELY] Labeling § 352.60 Labeling of permitted combinations of active ingredients. Statements of...

21 CFR 346.52 - Labeling of permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Labeling of permitted combinations of anorectal active ingredients. 346.52 Section 346.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... HUMAN USE Labeling § 346.52 Labeling of permitted combinations of anorectal active ingredients...

21 CFR 349.79 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of permitted combinations of active ingredients. 349.79 Section 349.79 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... § 349.79 Labeling of permitted combinations of active ingredients. Statements of identity, indications...

21 CFR 346.52 - Labeling of permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of permitted combinations of anorectal active ingredients. 346.52 Section 346.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... HUMAN USE Labeling § 346.52 Labeling of permitted combinations of anorectal active ingredients...

21 CFR 346.52 - Labeling of permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of permitted combinations of anorectal active ingredients. 346.52 Section 346.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... HUMAN USE Labeling § 346.52 Labeling of permitted combinations of anorectal active ingredients...

21 CFR 346.52 - Labeling of permitted combinations of anorectal active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Labeling of permitted combinations of anorectal active ingredients. 346.52 Section 346.52 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... HUMAN USE Labeling § 346.52 Labeling of permitted combinations of anorectal active ingredients...

21 CFR 349.79 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of permitted combinations of active ingredients. 349.79 Section 349.79 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... § 349.79 Labeling of permitted combinations of active ingredients. Statements of identity, indications...

Minocycline and N-acetylcysteine: A Synergistic Drug Combination to Treat Traumatic Brain Injury

DTIC Science & Technology

2012-10-01

W81XWH-10-2-0171 TITLE: Minocycline and N-acetylcysteine: a synergistic drug combination to treat traumatic brain injury PRINCIPAL INVESTIGATOR...TITLE AND SUBTITLE Minocycline and N-acetylcysteine: a synergistic drug combination to treat traumatic brain injury 5a. CONTRACT NUMBER 5b...The grantee previously found screened that the combination of minocycline (MINO) and N-acetyl cysteine (NAC) synergistically improved brain function

Effective drug combination for Caenorhabditis elegans nematodes discovered by output-driven feedback system control technique

PubMed Central

Ding, Xianting; Njus, Zach; Kong, Taejoon; Su, Wenqiong; Ho, Chih-Ming; Pandey, Santosh

2017-01-01

Infections from parasitic nematodes (or roundworms) contribute to a significant disease burden and productivity losses for humans and livestock. The limited number of anthelmintics (or antinematode drugs) available today to treat these infections are rapidly losing their efficacy as multidrug resistance in parasites becomes a global health challenge. We propose an engineering approach to discover an anthelmintic drug combination that is more potent at killing wild-type Caenorhabditis elegans worms than four individual drugs. In the experiment, freely swimming single worms are enclosed in microfluidic drug environments to assess the centroid velocity and track curvature of worm movements. After analyzing the behavioral data in every iteration, the feedback system control (FSC) scheme is used to predict new drug combinations to test. Through a differential evolutionary search, the winning drug combination is reached that produces minimal centroid velocity and high track curvature, while requiring each drug in less than their EC50 concentrations. The FSC approach is model-less and does not need any information on the drug pharmacology, signaling pathways, or animal biology. Toward combating multidrug resistance, the method presented here is applicable to the discovery of new potent combinations of available anthelmintics on C. elegans, parasitic nematodes, and other small model organisms. PMID:28983514

A Microparticle/Hydrogel Combination Drug-Delivery System for Sustained Release of Retinoids

PubMed Central

Gao, Song-Qi; Maeda, Tadao; Okano, Kiichiro; Palczewski, Krzysztof

2012-01-01

Purpose. To design and develop a drug-delivery system containing a combination of poly(d,l-lactide-co-glycolide) (PLGA) microparticles and alginate hydrogel for sustained release of retinoids to treat retinal blinding diseases that result from an inadequate supply of retinol and generation of 11-cis-retinal. Methods. To study drug release in vivo, either the drug-loaded microparticle–hydrogel combination was injected subcutaneously or drug-loaded microparticles were injected intravitreally into Lrat−/− mice. Orally administered 9-cis-retinoids were used for comparison and drug concentrations in plasma were determined by HPLC. Electroretinography (ERG) and both chemical and histologic analyses were used to evaluate drug effects on visual function and morphology. Results. Lrat−/− mice demonstrated sustained drug release from the microparticle/hydrogel combination that lasted 4 weeks after subcutaneous injection. Drug concentrations in plasma of the control group treated with the same oral dose rose to higher levels for 6−7 hours but then dropped markedly by 24 hours. Significantly increased ERG responses and a markedly improved retinal pigmented epithelium (RPE)–rod outer segment (ROS) interface were observed after subcutaneous injection of the drug-loaded delivery combination. Intravitreal injection of just 2% of the systemic dose of drug-loaded microparticles provided comparable therapeutic efficacy. Conclusions. Sustained release of therapeutic levels of 9-cis-retinoids was achieved in Lrat−/− mice by subcutaneous injection in a microparticle/hydrogel drug-delivery system. Both subcutaneous and intravitreal injections of drug-loaded microparticles into Lrat−/− mice improved visual function and retinal structure. PMID:22918645

Fixed-dose combination and single active ingredient drugs: a comparative cost analysis.

PubMed

Hao, Jing; Rodriguez-Monguio, Rosa; Seoane-Vazquez, Enrique

2016-01-01

Fixed-dose combination (FDC) drugs are formulations of two or more active ingredients. To assess the pricing structure and price difference of all US FDA-approved FDCs and single drugs included in the combination. Data were collected from the FDA Orange Book and Drugs@FDA. Average Wholesale Price (AWP) unit price data were derived from The Red Book. The FDA approved 117 FDC. The average AWP difference percentage between the FDC and the sum of the single drugs in the FDC is 84.9 ± 26.2%, and varied by therapeutic class (p < 0.001). The FDC AWP averaged 83.3 ± 23.4% of the single drug AWP sum when there are no generics, and 95.1 ± 42.3% (p < 0.01) when there are two generic single active ingredients in the FDC. The price difference between FDC and single active ingredients in the combination is correlated with the therapeutic class, the year of FDC approval, and the number of single ingredients in the combination that have generics.

Metformin and propranolol combination prevents cancer progression and metastasis in different breast cancer models

PubMed Central

Bondarenko, Maryna; Laluce, Nahuel Cesatti; Rozados, Viviana; Nicolas, André; Carré, Manon; Scharovsky, O. Graciela; Márquez, Mauricio Menacho

2017-01-01

Discovery of new drugs for cancer treatment is an expensive and time-consuming process and the percentage of drugs reaching the clinic remains quite low. Drug repositioning refers to the identification and development of new uses for existing drugs and represents an alternative drug development strategy. In this work, we evaluated the antitumor effect of metronomic treatment with a combination of two repositioned drugs, metformin and propranolol, in triple negative breast cancer models. By in vitro studies with five different breast cancer derived cells, we observed that combined treatment decreased proliferation (P < 0.001), mitochondrial activity (P < 0.001), migration (P < 0.001) and invasion (P < 0.001). In vivo studies in immunocompetent mice confirmed the potential of this combination in reducing tumor growth (P < 0.001) and preventing metastasis (P < 0.05). Taken together our results suggest that metformin plus propranolol combined treatment might be beneficial for triple negative breast cancer control, with no symptoms of toxicity. PMID:27926515

Cisplatin Cross-Linked Multifunctional Nanodrugplexes for Combination Therapy.

PubMed

Zhang, Weiqi; Tung, Ching-Hsuan

2017-03-15

Combination therapy efficiently tackles cancer by hitting multiple action mechanisms. However, drugs administered, simultaneously or sequentially, may not reach the targeted sites with the desired dose and ratio. The outcomes of combination therapy could be improved with a polymeric nanoparticle, which can simultaneously transport an optimal combination of drugs. We have demonstrated a simple one-pot strategy to formulate nanomedicines based on platinum coordination and the noncovalent interactions of the drugs. A naturally occurring polymer, hyaluronan (HA), was chosen as the building scaffold to form a nanodrugplex with cisplatin and aromatic-cationic drugs. The platinum coordination between cisplatin and HA induces the formation of a nanocomplex. The aromatic-cationic drugs are tightly packed by an electrostatic interaction and π-π stacking. The nanodrugplex bears excellent flexibility in drug combination and size control. It is stable in storage and has favorable release kinetics and targeting capabilities toward CD44, a receptor for HA that is highly expressed on many types of cancer cells.

Drug-device combination products: regulatory landscape and market growth.

PubMed

Bayarri, L

2015-08-01

Combination products are therapeutic and diagnostic products that combine drugs, devices and/or biological products, leading to safer and more effective treatments thanks to careful and precise drug targeting, local administration and individualized therapy. These technologies can especially benefit patients suffering from serious diseases and conditions such as cancer, heart disease, multiple sclerosis and diabetes, among others. On the other hand, drug-device combination products have also introduced a new dynamic in medical product development, regulatory approval and corporate interaction. Due to the increasing integration of drugs and devices observed in the latest generation of combination products, regulatory agencies have developed specific competences and regulations over the last decade. Manufacturers are required to fully understand the specific requirements in each country in order to ensure timely and accurate market access of new combination products, and the development of combination products involves a very specific pattern of interactions between manufacturers and regulatory agencies. The increased sophistication of the products brought to market over the last couple of decades has accentuated the need to develop drugs and devices collaboratively using resources from both industries, fostering the need of business partnering and technology licensing. This review will provide a global overview of the market trends, as well as (in the last section) an analysis of the drug-device combination products approved by the FDA during the latest 5 years. Copyright 2015 Prous Science, S.A.U. or its licensors. All rights reserved.

Asarones from Acorus calamus in combination with azoles and amphotericin B: a novel synergistic combination to compete against human pathogenic Candida species in vitro.

PubMed

Kumar, S Nishanth; Aravind, S R; Sreelekha, T T; Jacob, Jubi; Kumar, B S Dileep

2015-04-01

The increase in drug resistance to current antifungal drugs brings enormous challenges to the management of Candida infection. Therefore, there is a continuous need for the discovery of new antimicrobial agents that are effective against Candida infections especially from natural source especially from medical plants. The present investigation describes the synergistic anticandidal activity of two asarones (∞ and β) purified from Acorus calamus in combination with three clinically used antifungal drugs (fluconazole, clotrimazole, and amphotericin B). The synergistic anticandidal activities of asarones and drugs were assessed using the checkerboard microdilution and time-kill assays. The results of the present study showed that the combined effects of asarones and drugs principally recorded substantial synergistic activity (fractional inhibitory concentration index (FICI) <0.5). Time-kill study by combination of the minimal inhibitory concentration (MIC) of asarones and drugs (1:1) recorded that the growth of the Candida species was significantly arrested between 0 and 2 h and almost completely attenuated between 2 and 6 h of treatment. These findings have potential implications in adjourning the development of resistance as the anticandidal activity is achieved with lower concentrations of asarones and drugs. The combination of asarones and drugs also significantly inhibit the biofilm formation by Candida species, and this would also help to fight against drug resistance because biofilms formed by Candida species are ubiquitous in nature and are characterized by their recalcitrance toward antimicrobial treatment. The in vitro synergistic activity of asarones and drugs against pathogenic Candida species is reported here for the first time.

The within-host population dynamics of Mycobacterium tuberculosis vary with treatment efficacy.

PubMed

Trauner, Andrej; Liu, Qingyun; Via, Laura E; Liu, Xin; Ruan, Xianglin; Liang, Lili; Shi, Huimin; Chen, Ying; Wang, Ziling; Liang, Ruixia; Zhang, Wei; Wei, Wang; Gao, Jingcai; Sun, Gang; Brites, Daniela; England, Kathleen; Zhang, Guolong; Gagneux, Sebastien; Barry, Clifton E; Gao, Qian

2017-04-19

Combination therapy is one of the most effective tools for limiting the emergence of drug resistance in pathogens. Despite the widespread adoption of combination therapy across diseases, drug resistance rates continue to rise, leading to failing treatment regimens. The mechanisms underlying treatment failure are well studied, but the processes governing successful combination therapy are poorly understood. We address this question by studying the population dynamics of Mycobacterium tuberculosis within tuberculosis patients undergoing treatment with different combinations of antibiotics. By combining very deep whole genome sequencing (~1000-fold genome-wide coverage) with sequential sputum sampling, we were able to detect transient genetic diversity driven by the apparently continuous turnover of minor alleles, which could serve as the source of drug-resistant bacteria. However, we report that treatment efficacy has a clear impact on the population dynamics: sufficient drug pressure bears a clear signature of purifying selection leading to apparent genetic stability. In contrast, M. tuberculosis populations subject to less drug pressure show markedly different dynamics, including cases of acquisition of additional drug resistance. Our findings show that for a pathogen like M. tuberculosis, which is well adapted to the human host, purifying selection constrains the evolutionary trajectory to resistance in effectively treated individuals. Nonetheless, we also report a continuous turnover of minor variants, which could give rise to the emergence of drug resistance in cases of drug pressure weakening. Monitoring bacterial population dynamics could therefore provide an informative metric for assessing the efficacy of novel drug combinations.

Prevalence of Drug Combinations Increasing Bleeding Risk Among Warfarin Users With and Without Alzheimer's Disease.

PubMed

Taipale, Heidi; Vuorikari, Hanna; Tanskanen, Antti; Koponen, Marjaana; Tiihonen, Jari; Kettunen, Raimo; Hartikainen, Sirpa

2015-11-01

The aim of this study was to analyse the prevalence and predictors of drug combinations increasing bleeding risk among warfarin users with and without Alzheimer's disease (AD). This retrospective observational study utilised data from the Finnish MEDALZ-2005 cohort. The MEDALZ-2005 study included all community-dwelling persons with a clinically verified diagnosis of AD at the end of 2005, and one comparison person without AD for each case. Data on drug use was collected from the Prescription Register. We included persons who were warfarin users during the study period 2006-2009. Drug combinations increasing bleeding risk with warfarin included selective serotonin reuptake inhibitors (SSRIs), non-steroidal anti-inflammatory agents (NSAIDs), other antithrombotic drugs and tramadol. Factors associated with combination use were investigated with logistic regression. During the follow-up, 3385 persons with AD and 4830 persons without AD used warfarin. Drug combinations increasing bleeding risk were more common in warfarin users with AD than without AD [35.9 and 30.5%, respectively (p < 0.0001)]. The most common combination was SSRIs and warfarin, which was more common among persons with AD (23.8%) than among persons without AD (10.9%). NSAIDs and warfarin combination was more common among persons without AD. Combination use was associated with AD, female gender, younger age, diabetes mellitus, rheumatoid arthritis and asthma/chronic obstructive pulmonary disease (COPD). Use of drug combinations increasing bleeding risk was more common among warfarin users with AD. Special attention should be paid to minimise the duration of concomitant use and to find safer alternatives without increased bleeding risk.

Synergy testing of FDA-approved drugs identifies potent drug combinations against Trypanosoma cruzi.

PubMed

Planer, Joseph D; Hulverson, Matthew A; Arif, Jennifer A; Ranade, Ranae M; Don, Robert; Buckner, Frederick S

2014-07-01

An estimated 8 million persons, mainly in Latin America, are infected with Trypanosoma cruzi, the etiologic agent of Chagas disease. Existing antiparasitic drugs for Chagas disease have significant toxicities and suboptimal effectiveness, hence new therapeutic strategies need to be devised to address this neglected tropical disease. Due to the high research and development costs of bringing new chemical entities to the clinic, we and others have investigated the strategy of repurposing existing drugs for Chagas disease. Screens of FDA-approved drugs (described in this paper) have revealed a variety of chemical classes that have growth inhibitory activity against mammalian stage Trypanosoma cruzi parasites. Aside from azole antifungal drugs that have low or sub-nanomolar activity, most of the active compounds revealed in these screens have effective concentrations causing 50% inhibition (EC50's) in the low micromolar or high nanomolar range. For example, we have identified an antihistamine (clemastine, EC50 of 0.4 µM), a selective serotonin reuptake inhibitor (fluoxetine, EC50 of 4.4 µM), and an antifolate drug (pyrimethamine, EC50 of 3.8 µM) and others. When tested alone in the murine model of Trypanosoma cruzi infection, most compounds had insufficient efficacy to lower parasitemia thus we investigated using combinations of compounds for additive or synergistic activity. Twenty-four active compounds were screened in vitro in all possible combinations. Follow up isobologram studies showed at least 8 drug pairs to have synergistic activity on T. cruzi growth. The combination of the calcium channel blocker, amlodipine, plus the antifungal drug, posaconazole, was found to be more effective at lowering parasitemia in mice than either drug alone, as was the combination of clemastine and posaconazole. Using combinations of FDA-approved drugs is a promising strategy for developing new treatments for Chagas disease.

Efficacy of combination herbal product (Curcuma longa and Eugenia jambolana) used for diabetes mellitus.

PubMed

Rao, Sadia Saleem; Najam, Rahila

2016-01-01

The purpose of this research was to evaluate the efficacy of a combination herbal product that is traditionally used for managing diabetes mellitus. Herbal drug contains Curcuma longa and Eugenia jambolanain the ratio of 1:1. It was orally administered at the dose of 1082 mg/70 kg twice a day for a period of 6 weeks to alloxan induced diabetic rats and compared with glibenclamide (standard). The effects of drug were observed at intervals, with respect to random and fasting glucose levels. HbA1C was also monitored after the drug treatment to monitor the overall diabetic effect. Results revealed that the combination of two herbs significantly reduced fasting and random glucose levels with HbA1C of less than 6% (p<0.001) in comparison to diabetic control. The control of fasting blood glucose levels by herbal combination is similar to the standard drug, glibenclamide (p<0.05). Random glucose levels by herbal combination is better than standard drug after one week and six weeks of treatment (p<0.01 and p<0.001 respectively) and similar after third week of treatment (p<0.05). Also, herbal drug combination showed HbA1C closer to the standard drug. It shows that this herbal combination can be of potential benefit in managing diabetes mellitus in future.

Antibiotic combination efficacy (ACE) networks for a Pseudomonas aeruginosa model

PubMed Central

Barbosa, Camilo; Beardmore, Robert; Jansen, Gunther

2018-01-01

The spread of antibiotic resistance is always a consequence of evolutionary processes. The consideration of evolution is thus key to the development of sustainable therapy. Two main factors were recently proposed to enhance long-term effectiveness of drug combinations: evolved collateral sensitivities between the drugs in a pair and antagonistic drug interactions. We systematically assessed these factors by performing over 1,600 evolution experiments with the opportunistic nosocomial pathogen Pseudomonas aeruginosa in single- and multidrug environments. Based on the growth dynamics during these experiments, we reconstructed antibiotic combination efficacy (ACE) networks as a new tool for characterizing the ability of the tested drug combinations to constrain bacterial survival as well as drug resistance evolution across time. Subsequent statistical analysis of the influence of the factors on ACE network characteristics revealed that (i) synergistic drug interactions increased the likelihood of bacterial population extinction—irrespective of whether combinations were compared at the same level of inhibition or not—while (ii) the potential for evolved collateral sensitivities between 2 drugs accounted for a reduction in bacterial adaptation rates. In sum, our systematic experimental analysis allowed us to pinpoint 2 complementary determinants of combination efficacy and to identify specific drug pairs with high ACE scores. Our findings can guide attempts to further improve the sustainability of antibiotic therapy by simultaneously reducing pathogen load and resistance evolution. PMID:29708964

Combined Effects and Cross-Interactions of Different Antibiotics and Polypeptides in Salmonella bredeney.

PubMed

Ju, Xiangyu; Zhu, Mengjiao; Han, Jinzhi; Lu, Zhaoxin; Zhao, Haizhen; Bie, Xiaomei

2018-05-24

Salmonella spp. are health-threatening foodborne pathogens. The increasingly common spread of antibiotic-resistant Salmonella spp. is a major public healthcare issue worldwide. In this study, we wished to explore (1) antibiotic or polypeptide combinations to inhibit multidrug-resistant Salmonella bredeney and (2) the regulation of cross-resistance and collateral sensitivity of antibiotics and polypeptides. We undertook a study to select antibiotic combinations. Then, we promoted drug-resistant strains of S. bredeney after 15 types of antibiotic treatment. From each evolving population, the S. bredeney strain was exposed to a particular single drug. Then, we analyzed how the evolved S. bredeney strains acquired resistance or susceptibility to other drugs. A total of 105 combinations were tested against S. bredeney following the protocols of CLSI-2016 and EUCAST-2017. The synergistic interactions between drug pairings were diverse. Notably, polypeptides were more likely to be linked to synergistic combinations: 56% (19/34) of the synergistic pairings were relevant to polypeptides. Simultaneously, macrolides demonstrated antagonism toward polypeptides. The latter were more frequently related to collateral sensitivity than the other drugs because the other 13 drugs sensitized S. bredeney to polypeptides. In an experimental evolution involving 15 drugs, single drug-evolved strains were examined against the other 14 drugs, and the results were compared with the minimal inhibitory concentration of the ancestral strain. Single drug-evolved S. bredeney strains could alter the sensitivity to other drugs, and S. bredeney evolution against antibiotics could sensitize it to polypeptides.

Access to artemisinin-based combination therapies and other anti-malarial drugs in Kinshasa.

PubMed

Nkoli Mandoko, P; Sinou, V; Moke Mbongi, D; Ngoyi Mumba, D; Kahunu Mesia, G; Losimba Likwela, J; Bi Shamamba Karhemere, S; Muepu Tshilolo, L; Tamfum Muyembe, J-J; Parzy, D

2018-06-01

Artemisinin-based combination therapies have been available since 2005 in the Democratic Republic of the Congo to treat malaria and to overcome the challenge of anti-malarial drug resistance as well as to improve access to effective treatments. The private sector is the primary distribution source for anti-malarial drugs and thus, has a key position among the supply chain actors for a rational and proper use of anti-malarial drugs. We aimed to assess access to nationally recommended anti-malarial drugs in private sector pharmacies of the capital-city of Kinshasa. We performed a cross-sectional survey of 404 pharmacies. Anti-malarial drugs were stocked in all surveyed pharmacies. Non-artemisinin-based anti-malarial therapies such as quinine or sulfadoxine-pyrimethamine, were the most frequently stocked drugs (93.8% of pharmacies). Artemisinin-based combination therapies were stocked in 88% of pharmacies. Artemether-lumefantrine combinations were the most frequently dispensed drugs (93% of pharmacies), but less than 3% were quality-assured products. Other non-officially recommended artemisinin-based therapies including oral monotherapies were widely available. Artemisinin-based combination therapies were widely available in the private pharmacies of Kinshasa. However, the private sector does not guarantee the use of nationally recommended anti-malarial drugs nor does it give priority to quality-assured anti-malarial drugs. These practices contribute to the risk of emergence and spread of resistance to anti-malarial drugs and to increasing treatment costs. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

21 CFR 352.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... statement of identity sections of the applicable OTC drug monographs. For a combination drug product that... applicable OTC drug monographs. (b) Indications. The labeling of the product states, under the heading “Uses... the applicable OTC drug monographs, unless otherwise stated in this paragraph. Other truthful and...

21 CFR 352.60 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... statement of identity sections of the applicable OTC drug monographs. For a combination drug product that... applicable OTC drug monographs. (b) Indications. The labeling of the product states, under the heading “Uses... the applicable OTC drug monographs, unless otherwise stated in this paragraph. Other truthful and...

Low-Dose Tramadol and Non-Steroidal Anti-Inflammatory Drug Combination Therapy Prevents the Transition to Chronic Low Back Pain.

PubMed

Inage, Kazuhide; Orita, Sumihisa; Yamauchi, Kazuyo; Suzuki, Takane; Suzuki, Miyako; Sakuma, Yoshihiro; Kubota, Go; Oikawa, Yasuhiro; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Shiga, Yasuhiro; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Takahashi, Kazuhisa; Ohtori, Seiji

2016-08-01

Retrospective study. To determine whether low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy could prevent the transition of acute low back pain to chronic low back pain. Inadequately treated early low back pain transitions to chronic low back pain occur in approximately 30% of affected individuals. The administration of non-steroidal anti-inflammatory drugs is effective for treatment of low back pain in the early stages. However, the treatment of low back pain that is resistant to non-steroidal anti-inflammatory drugs is challenging. Patients who presented with acute low back pain at our hospital were considered for inclusion in this study. After the diagnosis of acute low back pain, non-steroidal anti-inflammatory drug administration was started. Forty patients with a visual analog scale score of >5 for low back pain 1 month after treatment were finally enrolled. The first 20 patients were included in a non-steroidal anti-inflammatory drug group, and they continued non-steroidal anti-inflammatory drug therapy for 1 month. The next 20 patients were included in a combination group, and they received low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy for 1 month. The incidence of adverse events and the improvement in the visual analog scale score at 2 months after the start of treatment were analyzed. No adverse events were observed in the non-steroidal anti-inflammatory drug group. In the combination group, administration was discontinued in 2 patients (10%) due to adverse events immediately following the start of tramadol administration. At 2 months, the improvement in the visual analog scale score was greater in the combination group than in the non-steroidal anti-inflammatory drug group (p<0.001). Low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy might decrease the incidence of adverse events and prevent the transition of acute low back pain to chronic low back pain.

Drug-device combination products in the twenty-first century: epinephrine auto-injector development using human factors engineering.

PubMed

Edwards, Eric S; Edwards, Evan T; Simons, F Estelle R; North, Robert

2015-05-01

The systematic application of human factors engineering (HFE) principles to the development of drug-device combination products, including epinephrine auto-injectors (EAIs), has the potential to improve the effectiveness and safety of drug administration. A PubMed search was performed to assess the role of HFE in the development of drug-device combination products. The following keywords were used in different combinations: 'human factors engineering,' 'human factors,' 'medical products,' 'epinephrine/adrenaline auto-injector,' 'healthcare' and 'patient safety.' This review provides a summary of HFE principles and their application to the development of drug-device combination products as advised by the US FDA. It also describes the HFE process that was applied to the development of Auvi-Q, a novel EAI, highlighting specific steps that occurred during the product-development program. For drug-device combination products, device labeling and usability are critical and have the potential to impact clinical outcomes. Application of HFE principles to the development of drug-delivery devices has the potential to improve product quality and reliability, reduce risk and improve patient safety when applied early in the development process. Additional clinical and real-world studies will confirm whether the application of HFE has helped to develop an EAI that better meets the needs of patients at risk of anaphylaxis.

Synergistic combinations of antifungals and anti-virulence agents to fight against Candida albicans.

PubMed

Cui, Jinhui; Ren, Biao; Tong, Yaojun; Dai, Huanqin; Zhang, Lixin

2015-01-01

Candida albicans, one of the pathogenic Candida species, causes high mortality rate in immunocompromised and high-risk surgical patients. In the last decade, only one new class of antifungal drug echinocandin was applied. The increased therapy failures, such as the one caused by multi-drug resistance, demand innovative strategies for new effective antifungal drugs. Synergistic combinations of antifungals and anti-virulence agents highlight the pragmatic strategy to reduce the development of drug resistant and potentially repurpose known antifungals, which bypass the costly and time-consuming pipeline of new drug development. Anti-virulence and synergistic combination provide new options for antifungal drug discovery by counteracting the difficulty or failure of traditional therapy for fungal infections.

Dopaminergic and Serotonergic Drug Use: A Nationwide Register-Based Study of Over 1 300 000 Older People

PubMed Central

Johnell, Kristina; Fischer, Håkan

2011-01-01

Objective To investigate the use of dopaminergic and serotonergic drugs in elderly people. Methods We analyzed data on age, sex and dispensed drugs for individuals aged ≥65 years registered in the Swedish Prescribed Drug Register from July to September 2008 (n = 1 347 564; 81% of the total population aged ≥65 years in Sweden). Main outcome measures were dopaminergic (enhancing and/or lowering) and serotonergic (enhancing and/or lowering) drugs and combinations of these. Results Dopaminergic and serotonergic drugs were used by 5.6% and 13.2% the participants, respectively. Female gender was related to use of both dopaminergic and, particularly, serotonergic drugs. Higher age was associated with use of dopamine lowering drugs and serotonergic drugs, whereas the association with use of dopamine enhancing drugs declined in the oldest old. The occurrence of combinations of dopaminergic and serotonergic drugs was generally low, with dopamine lowering + serotonin lowering drug the most common combination (1.6%). Female gender was associated with all of the combinations of dopaminergic and serotonergic drugs, whereas age showed a mixed pattern. Conclusion Approximately one out of ten older patients uses serotonergic drugs and one out of twenty dopaminergic drugs. The frequent use of dopaminergic and serotonergic drugs in the elderly patients is a potential problem due to the fact that aging is associated with a down-regulation of both these monoaminergic systems. Future studies are needed for evaluation of the impact of these drugs on different cognitive and emotional functions in old age. PMID:21858217

Antifungal activity of silver nanoparticles in combination with nystatin and chlorhexidine digluconate against Candida albicans and Candida glabrata biofilms.

PubMed

Monteiro, Douglas R; Silva, Sónia; Negri, Melyssa; Gorup, Luiz F; de Camargo, Emerson R; Oliveira, Rosário; Barbosa, Debora B; Henriques, Mariana

2013-11-01

Although silver nanoparticles (SN) have been investigated as an alternative to conventional antifungal drugs in the control of Candida-associated denture stomatitis, the antifungal activity of SN in combination with antifungal drugs against Candida biofilms remains unknown. Therefore, the aim of this study was to evaluate the antifungal efficacy of SN in combination with nystatin (NYT) or chlorhexidine digluconate (CHG) against Candida albicans and Candida glabrata biofilms. The drugs alone or combined with SN were applied on mature Candida biofilms (48 h), and after 24 h of treatment their antibiofilm activities were assessed by total biomass quantification (by crystal violet staining) and colony forming units enumeration. The structure of Candida biofilms was analysed by scanning electron microscopy (SEM) images. The data indicated that SN combined with either NYT or CHG demonstrated synergistic antibiofilm activity, and this activity was dependent on the species and on the drug concentrations used. SEM images showed that some drug combinations were able to disrupt Candida biofilms. The results of this study suggest that the combination of SN with NYT or CHG may have clinical implications in the treatment of denture stomatitis. However, further studies are needed before recommending the use of these drugs safely in clinical situations. © 2013 Blackwell Verlag GmbH.

Evaluation of methylene blue, pyrimethamine and its combination on an in vitro Neospora caninum model.

PubMed

Pereira, Luiz Miguel; Vigato-Ferreira, Isabel Cristina; DE Luca, Gabriela; Bronzon DA Costa, Cássia Mariana; Yatsuda, Ana Patrícia

2017-05-01

Neospora caninum is an apicomplexan parasite strongly related to reproductive problems in cattle. The neosporosis control is not well established and several fronts are under development, predominantly based on immune protection, immunomodulation and chemotherapy. The use of anti-malarial drugs as therapeutic sources has, in theory, considerable potential for any apicomplexan. Drugs such as methylene blue (MB) and pyrimethamine (Pyr) represent therapeutic options for malaria; thus, their use for neosporosis should be assessed. In this work, we tested the effects of MB and Pyr on N. caninum proliferation and clearance, using LacZ-tagged tachyzoites. The drugs inhibited at nanomolar dosages and its combination demonstrated an antagonistic interaction in proliferation assays, according to the Chou and Talalay method for drug combination index. However, the drug combination significantly improved the parasite in vitro clearance. The repositioning of well-established drugs opens a short-term strategy to obtain low-cost therapeutics approaches against neosporosis.

78 FR 52536 - Withdrawal of Approval of New Animal Drug Applications; Diethylcarbamazine; Nicarbazin...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

...] Withdrawal of Approval of New Animal Drug Applications; Diethylcarbamazine; Nicarbazin; Penicillin; Roxarsone..., penicillin, and roxarsone in 3-way, combination drug Type C medicated feeds for broiler chickens and NADA 098-374 for use of nicarbazin and penicillin in 2-way, combination drug Type C medicated feeds for broiler...

[The use of low-frequency magnetotherapy and EHF puncture in the combined treatment of arterial hypertension in vibration-induced disease].

PubMed

Drobyshev, V A; Filippova, G N; Loseva, M I; Shpagina, L A; Shelepova, N V; Zhelezniak, M S

2000-01-01

Combination of EHF therapy + magnetotherapy + drugs results in faster and persistent hypotensive and analgetic effect compared to standard drug therapy, potentiates action of vascular drugs on cerebral and peripheral circulation, reduces dose of hypotensive drugs in patients with arterial hypertension and vibration disease.

Sildenafil (Viagra) and club drug use in gay and bisexual men: the role of drug combinations and context.

PubMed

Halkitis, Perry N; Green, Kelly A

2007-06-01

Data ascertained in a study of club drug use among 450 gay and bisexual men indicate that at least one class of PDE-5 (phosphodiesterase type 5 inhibitor, sildenafil [Viagra]) is used frequently in combination with club drugs such as methamphetamine, MDMA (3,4 methylenedioxymethamphetamine [ecstasy]), ketamine, cocaine, and GHB (gamma hydroxy butyrate). Patterns of sildenafil use in combination with each of the club drugs differ among key demographics including race and age. Multivariate models, controlling for demographic factors, suggest that contextual factors are key to understanding why men mix sildenafil with club drugs, although age may still be an important issue to consider. Of particular importance is the fact that use of club drugs in combination with sildenafil is strongly associated with circuit and sex parties, where a centerpiece of these environments focuses on sexual exchange. These models imply interplay between person-level and contextual factors in explaining drug use patterns and further indicate that interventions aimed at addressing illicit substance use must carefully consider the role of environmental factors in explaining behavior.

The application of a novel high-resolution mass spectrometry-based analytical strategy to rapid metabolite profiling of a dual drug combination in humans.

PubMed

Xing, Jie; Zang, Meitong; Liu, Huixiang

2017-11-15

Metabolite profiling of combination drugs in complex matrix is a big challenge. Development of an effective data mining technique for simultaneously extracting metabolites of one parent drug from both background matrix and combined drug-related signals could be a solution. This study presented a novel high resolution mass spectrometry (HRMS)-based data-mining strategy to fast and comprehensive metabolite identification of combination drugs in human. The model drug combination was verapamil-irbesartan (VER-IRB), which is widely used in clinic to treat hypertension. First, mass defect filter (MDF), as a targeted data mining tool, worked effectively except for those metabolites with similar MDF values. Second, the accurate mass-based background subtraction (BS), as an untargeted data-mining tool, was able to recover all relevant metabolites of VER-IRB from the full-scan MS dataset except for trace metabolites buried in the background noise and/or combined drug-related signals. Third, the novel ring double bond (RDB; valence values of elements in structure) filter, could show rich structural information in more sensitive full-scan MS chromatograms; however, it had a low capability to remove background noise and was difficult to differentiate the metabolites with RDB coverage. Fourth, an integrated strategy, i.e., untargeted BS followed by RDB, was effective for metabolite identification of VER and IRB, which have different RDB values. Majority of matrix signals were firstly removed using BS. Metabolite ions for each parent drug were then isolated from remaining background matrix and combined drug-related signals by imposing of preset RDB values/ranges around the parent drug and selected core substructures. In parallel, MDF was used to recover potential metabolites with similar RDB. As a result, a total of 74 metabolites were found for VER-IRB in human plasma and urine, among which ten metabolites have not been previously reported in human. The results demonstrated that the combination of accurate mass-based multiple data-mining techniques, i.e., untargeted background subtraction followed by ring double bond filtering in parallel with targeted mass defect filtering, can be a valuable tool for rapid metabolite profiling of combination drug. Copyright © 2017 Elsevier B.V. All rights reserved.

[Considerations about the efficiency of treatment regimens with fixed Rifampicin-Isoniazid combinations in pulmonary tuberculosis].

PubMed

Munteanu, Ioana; Husar, Iulia; Didilescu, C; Stoicescu, I P

2004-01-01

Here are presented the results of a prospective, randomized study regarding the efficiency of regimens with fixed drug combination Rifampicin-Isoniazide manufactured by Antibiotics S.A. of Iasi in comparison with single drugs routinely used in treatment of patients with pulmonary tuberculosis. Newly diagnosed (confirmed by smear and culture) pulmonary tuberculosis patients were selected, and those who accepted to be included in the study, were admitted to the National Institute of Pneumology "Marius Nasta" between August 2001 and September 2002. At the time of admission, they were randomized into two groups: 20 patients received fixed drug combination RMP300 HIN150, and 18 patients received RMP and HIN in single drug tablets (2 patients were excluded). The follow-up of the patients was for one year from the date of enclosure. The smear conversion rate was 83,3% for the patients using single drug tablets, and 70% for those using fixed drug combination, motivated with some more severe TB patterns. The success rate was 100% for all TB patients. Although the present study was done for few patients, we can say that it demonstrated the same efficiency of fixed drug combination produced in Romania, with the single drug tablets, and it suggests a better compliance to treatment with a lower price.

Prescription of fixed dose combination drugs for diarrhoea.

PubMed

Chakrabarti, Amit

2007-01-01

Fixed-dose combinations (FDCs) of an antiprotozoal and an antibacterial, for treatment of diarrhoea, have been available in the Indian pharmaceutical market for about a decade. There is little evidence to substantiate this combination therapy. We evaluated 2,163 physician prescriptions for diarrhoea and found that 59 per cent of prescriptions were for FDCs. This is unethical because prescribing such combinations exposes a patient to higher risks of adverse drug reactions and also increases the chances of drug resistance. Physicians' prescribing practices in India are influenced by socioeconomic factors and the pharmaceutical industry's marketing techniques that include giving incentives to physicians to prescribe certain drugs.

Combination of mild hypothermia with neuroprotectants has greater neuroprotective effects during oxygen-glucose deprivation and reoxygenation-mediated neuronal injury

PubMed Central

Gao, Xiao-Ya; Huang, Jian-Ou; Hu, Ya-Fang; Gu, Yong; Zhu, Shu-Zhen; Huang, Kai-Bin; Chen, Jin-Yu; Pan, Su-Yue

2014-01-01

Co-treatment of neuroprotective reagents may improve the therapeutic efficacy of hypothermia in protecting neurons during ischemic stroke. This study aimed to find promising drugs that enhance the neuroprotective effect of mild hypothermia (MH). 26 candidate drugs were selected based on different targets. Primary cultured cortical neurons were exposed to oxygen-glucose deprivation and reoxygenation (OGD/R) to induce neuronal damage, followed by either single treatment (a drug or MH) or a combination of a drug and MH. Results showed that, compared with single treatment, combination of MH with brain derived neurotrophic factor, glibenclamide, dizocilpine, human urinary kallidinogenase or neuroglobin displayed higher proportion of neuronal cell viability. The latter three drugs also caused less apoptosis rate in combined treatment. Furthermore, co-treatment of those three drugs and MH decreased the level of reactive oxygen species (ROS) and intracellular calcium accumulation, as well as stabilized mitochondrial membrane potential (MMP), indicating the combined neuroprotective effects are probably via inhibiting mitochondrial apoptosis pathway. Taken together, the study suggests that combined treatment with hypothermia and certain neuroprotective reagents provide a better protection against OGD/R-induced neuronal injury. PMID:25404538

Effects of blood-activating and stasis-removing drugs combined with VEGF gene transfer on angiogenesis in ischemic necrosis of the femoral head.

PubMed

Li, Jun-Hui; Wu, Ya-Ling; Ye, Jian-Hong; Ning, Ya-Gong; Yu, Hai-Ying; Peng, Zhong-Jie; Luan, Xiao-Wen

2009-09-01

To observe the promoting effects of blood-activating and stasis-removing Chinese drugs combined with vascular endothelial growth factor (VEGF) gene transfer on angiogenesis in ischemic necrosis of the femoral head. Forty Japanese giant-ear rabbits were randomly divided into a control group, a model group, a Chinese drug group, a gene group, and a combined group. After 8 weeks of treatment, the rate of VEGF positive cell expression in the synovium of the femoral head was measured using the immunohistochemical method, and the number of blood vessels in the femoral head was measured by digital subtraction angiography. The rate of VEGF positive cell expression in the model group was significantly lower than that in the Chinese drug group (P < 0.05) and very significantly lower than those in other groups (P < 0.01); but in the combined group it was significantly higher than in the Chinese drug group (P < 0.05). The differences in the number of blood vessels in area A between the model group and other groups were not statistically significant. However, in area B, the number of blood vessels significantly increased in the control group, the gene group and the combined group as compared with the model group (P < 0.05), and in the combined group the number of blood vessels was significantly more than in the gene group (P < 0.05); but in the Chinese drug group it was not significantly different than the model group (P > 0.05). Either the blood-activating and stasis-removing Chinese drugs or VEGF gene transfer can promote the angiogenesis and building of collateral circulation for femoral head ischemic necrosis, and the combined therapy with Chinese drugs or VEGF gene transfer may show a better therapeutic effect. The present study provides an experimental basis for clinical application of the combined therapy with the blood-activating and stasis-removing Chinese drugs and VEGF gene transfer.

In-vitro and in-vivo inhibition of melanoma growth and metastasis by the drug combination of celecoxib and dacarbazine.

PubMed

Sadhu, Satya S; Wang, Shenggang; Averineni, Ranjith K; Seefeldt, Teresa; Yang, Yang; Guan, Xiangming

2016-12-01

Celecoxib has been found to be effective in cancer prevention and treatment. Its combination with other chemotherapeutic agents was reported to produce synergistic/additive effects on various cancers. Dacarbazine (DTIC) is one of the most commonly used drugs in the treatment of metastatic melanoma. This investigation aimed to determine the in-vitro and in-vivo effects of the drug combination of celecoxib and DTIC on melanoma growth and metastasis. Melanoma cells B16-F10 and SK-MEL-28, and female C57BL/6 mice were used for the study. Our in-vitro data showed that significant synergistic effects were obtained when celecoxib was used together with various concentrations of DTIC. A study with B16-F10 cells using flow cytometry analysis showed that the drug combination induced significantly more apoptosis than each drug used individually. Our in-vivo results showed that the drug combination was much more effective than each drug used alone for the inhibition of both melanoma growth and metastasis in the B16-F10+C57BL/6 mouse models. For melanoma growth, the median survival rates for phosphate-buffered saline (PBS) (control), celecoxib (30 mg/kg), DTIC-1 (10 mg/kg), DTIC-2 (positive control, 50 mg/kg), and the drug combination (DTIC 10 mg/kg+celecoxib 30 mg/kg) were 6, 6.5, 7.5, 7.5, and 9 days, respectively. For melanoma metastasis, the average number of metastatic tumors in murine lungs was 53.7±10.7, 31.8±18.6, 21.2±21.7, 7.0±9.0, and 0.8±2.0 for PBS, DTIC-1, celecoxib, the drug combination, and DTIC-2. Our results warrant further investigation of the combination as an effective treatment for melanoma patients.

Local Drug Infiltration Analgesia During Knee Surgery to Reduce Postoperative Pain in Rats.

PubMed

Buvanendran, Asokumar; Kroin, Jeffrey S; Della Valle, Craig J; Moric, Mario; Tuman, Kenneth J

2016-01-01

There is increasing interest in local infiltration analgesia (LIA) to reduce postoperative pain with knee surgery. Despite widespread use of LIA, wide variations in drug combinations, infiltration techniques, and the concomitant use of systemic analgesics have made it difficult to determine the optimal drug combination for LIA.Using a previously validated animal knee surgery model, we aimed to determine the optimal combination of medications to reduce postoperative pain, and the best anatomical location and timing for local drug injection during surgery. Knee surgery was performed in an adult rat model under isoflurane anesthesia. During surgery, combinations of bupivacaine, ketorolac, dexamethasone, and morphine were injected around the knee and compared to saline placebo. Similar medications were injected systemically as a comparator group. Postoperative pain was assessed by measuring spontaneous rearing activity. Injections were given after bone drilling and/or just before wound closure. The 3-drug LIA combination of bupivacaine, ketorolac, and dexamethasone increased rearing (decreased pain) at 2 hours (P = 0.0198) and 24 hours (P = 0.0384) postsurgery compared to saline. The same drugs injected systemically had no effect. The ketorolac/dexamethasone combination for LIA was also effective at 2 hours (P = 0.0006) and 24 hours (P = 0.0279), and ketorolac alone reduced pain at 2 hours (P = 0.0045). Bupivacaine alone was less effective, and the addition of morphine had no effect. The 3-drug combination infiltrated just after creating holes in bone was more effective than when given into the wound just before wound closure. Our animal study suggests that clinical trials with LIA combinations of local anesthetic, nonsteroidal anti-inflammatory drug, and corticosteroid might be useful for reducing postoperative pain after knee surgery, with the nonsteroidal anti-inflammatory drug having the greatest effect.Perioperative physicians should consider delivering LIA earlier during the procedure as opposed to solely at the time of wound closure.

Patterns of Polydrug Use Among Ketamine Injectors in New York City

PubMed Central

LANKENAU, STEPHEN E.; CLATTS, MICHAEL C.

2007-01-01

Polydrug use is an important public health issue since it has been linked to significant adverse health outcomes. Recently, club drugs, including ketamine and other drugs used in dance/rave scenes, have been identified as key substances in new types of polydrug using patterns. While seemingly a self-explanatory concept, “polydrug” use constitutes multiple drug using practices that may impact upon health risks. Ketamine, a club drug commonly administered intranasally among youth for its disassociative properties, has emerged as a drug increasingly prevalent among a new hidden population of injection drug users (IDUs). Using an ethno-epidemiological methodology, we interviewed 40 young (<25 years old) ketamine injectors in New York during 2000–2002 to describe the potential health risks associated with ketamine and polydrug use. Findings indicate that ketamine was typically injected or sniffed in the context of a polydrug using event. Marijuana, alcohol, PCP, and speed were among the most commonly used drugs during recent ketamine using events. Polydrug using events were often quite variable regarding the sequencing of drug use, the drug combinations consumed, the forms of the drug utilized, and the modes of administrating the drug combinations. Future research should be directed towards developing a more comprehensive description of the risks associated with combining ketamine with other drugs, such as drug overdoses, the transmission of bloodborne pathogens, such as HIV and HCV, the short- and long-term effects of drug combinations on cognitive functioning, and other unanticipated consequences associated with polydrug use. PMID:16048823

Drug Combination Synergy in Worm-like Polymeric Micelles Improves Treatment Outcome for Small Cell and Non-Small Cell Lung Cancer.

PubMed

Wan, Xiaomeng; Min, Yuanzeng; Bludau, Herdis; Keith, Andrew; Sheiko, Sergei S; Jordan, Rainer; Wang, Andrew Z; Sokolsky-Papkov, Marina; Kabanov, Alexander V

2018-03-27

Nanoparticle-based systems for concurrent delivery of multiple drugs can improve outcomes of cancer treatments, but face challenges because of differential solubility and fairly low threshold for incorporation of many drugs. Here we demonstrate that this approach can be used to greatly improve the treatment outcomes of etoposide (ETO) and platinum drug combination ("EP/PE") therapy that is the backbone for treatment of prevalent and deadly small cell lung cancer (SCLC). A polymeric micelle system based on amphiphilic block copolymer poly(2-oxazoline)s (POx) poly(2-methyl-2-oxazoline- block-2-butyl-2-oxazoline- block-2-methyl-2-oxazoline) (P(MeOx- b-BuOx- b-MeOx) is used along with an alkylated cisplatin prodrug to enable co-formulation of EP/PE in a single high-capacity vehicle. A broad range of drug mixing ratios and exceptionally high two-drug loading of over 50% wt. drug in dispersed phase is demonstrated. The highly loaded POx micelles have worm-like morphology, unprecedented for drug loaded polymeric micelles reported so far, which usually form spheres upon drug loading. The drugs co-loading in the micelles result in a slowed-down release, improved pharmacokinetics, and increased tumor distribution of both drugs. A superior antitumor activity of co-loaded EP/PE drug micelles compared to single drug micelles or their combination as well as free drug combination was demonstrated using several animal models of SCLC and non-small cell lung cancer.

Combinative Particle Size Reduction Technologies for the Production of Drug Nanocrystals

PubMed Central

Salazar, Jaime; Müller, Rainer H.; Möschwitzer, Jan P.

2014-01-01

Nanosizing is a suitable method to enhance the dissolution rate and therefore the bioavailability of poorly soluble drugs. The success of the particle size reduction processes depends on critical factors such as the employed technology, equipment, and drug physicochemical properties. High pressure homogenization and wet bead milling are standard comminution techniques that have been already employed to successfully formulate poorly soluble drugs and bring them to market. However, these techniques have limitations in their particle size reduction performance, such as long production times and the necessity of employing a micronized drug as the starting material. This review article discusses the development of combinative methods, such as the NANOEDGE, H 96, H 69, H 42, and CT technologies. These processes were developed to improve the particle size reduction effectiveness of the standard techniques. These novel technologies can combine bottom-up and/or top-down techniques in a two-step process. The combinative processes lead in general to improved particle size reduction effectiveness. Faster production of drug nanocrystals and smaller final mean particle sizes are among the main advantages. The combinative particle size reduction technologies are very useful formulation tools, and they will continue acquiring importance for the production of drug nanocrystals. PMID:26556191

[Joint action of nitrofuran preparations and bile acids on bacteria of the genus Proteus].

PubMed

Sytnik, I A; Puzakova, E V

1975-01-01

Sensitivity of 25 fresh isolates of Proteus to some nitrofuran drugs most widely used in the clinical practice, such as furacillin, furagin, furazolidone and nitrofurantoin was studied. When the drugs were used in combination with some bile acids, i.e. desoxycholic, dehydrocholic, cholic and glycocholic acids, significant in vitro potentiation of the antibacterial activity of the nitrofurans against the isolates was observed. The combinations of the drugs with desoxycholic acid proved to be most effective. In the presence of this acid the bacteriostatic dose of the drugs decreased several thousand times. Combination of the nitrofurans with the other acids resulted in an increase in the antimicrobial activity amounting to several hundred times. The combinations of the drugs with the bile acids had not only bacteriostatic but also bactericidal effect.

Success rates for product development strategies in new drug development.

PubMed

Dahlin, E; Nelson, G M; Haynes, M; Sargeant, F

2016-04-01

While research has examined the likelihood that drugs progress across phases of clinical trials, no research to date has examined the types of product development strategies that are the most likely to be successful in clinical trials. This research seeks to identify the strategies that are most likely to reach the market-those generated using a novel product development strategy or strategies that combine a company's expertise with both drugs and indications, which we call combined experience strategies. We evaluate the success of product development strategies in the drug development process for a sample of 2562 clinical trials completed by 406 US pharmaceutical companies. To identify product development strategies, we coded each clinical trial according to whether it consisted of an indication or a drug that was new to the firm. Accordingly, a clinical trial that consists of both an indication and a drug that were both new to the firm represents a novel product development strategy; indication experience is a product development strategy that consists of an indication that a firm had tested previously in a clinical trial, but with a drug that was new to the firm; drug experience is a product development strategy that consists of a drug that the firm had prior experience testing in clinical trials, but with an indication that was new to the firm; combined experience consists of both a drug and an indication that the firm had experience testing in clinical trials. Success rates for product development strategies across clinical phases were calculated for the clinical trials in our sample. Combined experience strategies had the highest success rate. More than three and a half percent (0·036) of the trials that combined experience with drugs and indications eventually reached the market. The next most successful strategy is drug experience (0·025) with novel strategies trailing closely (0·024). Indication experience strategies are the least successful (0·008). These differences are statistically significant. The primary contribution of this study is that product development strategies combining experience with drugs and indications strategies are the most likely to reach the market, even though they are least common strategy. Therefore, combined experience strategies remain underutilized. The findings also suggest a promising path for pursuing combined experience strategies: gaining expertise with drugs is likely to be a more effective path to gaining the expertise necessary for developing subsequent recombination strategies. © 2016 John Wiley & Sons Ltd.

Platinum covalent shell cross-linked micelles designed to deliver doxorubicin for synergistic combination cancer therapy

PubMed Central

Zhu, Caiying; Xiao, Jingjing; Tang, Ming; Feng, Hua; Chen, Wulian; Du, Ming

2017-01-01

The preparation of polymer therapeutics capable of controlled release of multiple chemotherapeutic drugs has remained a tough problem in synergistic combination cancer therapy. Herein, a novel dual-drug co-delivery system carrying doxorubicin (DOX) and platinum(IV) (Pt[IV]) was developed. An amphiphilic diblock copolymer, PCL-b-P(OEGMA-co-AzPMA), was synthesized and used as a nanoscale drug carrier in which DOX and Pt(IV) could be packaged together. The copolymers were shell cross-linked by Pt(IV) prodrug via a click reaction. Studies on the in vitro drug release and cellular uptake of the dual-drug co-delivery system showed that the micelles were effectively taken up by the cells and simultaneously released drugs in the cells. Futhermore, the co-delivery polymer nanoparticles caused much higher cell death in HeLa and A357 tumor cells than either the free drugs or single-drug-loaded micelles at the same dosage, exhibiting a synergistic combination of DOX and Pt(IV). The results obtained with the shell cross-linked micelles based on an anticancer drug used as a cross-linking linkage suggested a promising application of the micelles for multidrug delivery in combination cancer therapy. PMID:28553108

Artificial intelligence in drug combination therapy.

PubMed

Tsigelny, Igor F

2018-02-09

Currently, the development of medicines for complex diseases requires the development of combination drug therapies. It is necessary because in many cases, one drug cannot target all necessary points of intervention. For example, in cancer therapy, a physician often meets a patient having a genomic profile including more than five molecular aberrations. Drug combination therapy has been an area of interest for a while, for example the classical work of Loewe devoted to the synergism of drugs was published in 1928-and it is still used in calculations for optimal drug combinations. More recently, over the past several years, there has been an explosion in the available information related to the properties of drugs and the biomedical parameters of patients. For the drugs, hundreds of 2D and 3D molecular descriptors for medicines are now available, while for patients, large data sets related to genetic/proteomic and metabolomics profiles of the patients are now available, as well as the more traditional data relating to the histology, history of treatments, pretreatment state of the organism, etc. Moreover, during disease progression, the genetic profile can change. Thus, the ability to optimize drug combinations for each patient is rapidly moving beyond the comprehension and capabilities of an individual physician. This is the reason, that biomedical informatics methods have been developed and one of the more promising directions in this field is the application of artificial intelligence (AI). In this review, we discuss several AI methods that have been successfully implemented in several instances of combination drug therapy from HIV, hypertension, infectious diseases to cancer. The data clearly show that the combination of rule-based expert systems with machine learning algorithms may be promising direction in this field. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

In vitro and in vivo characterization of doxorubicin and vincristine coencapsulated within liposomes through use of transition metal ion complexation and pH gradient loading.

PubMed

Abraham, Sheela A; McKenzie, Cheryl; Masin, Dana; Ng, Rebecca; Harasym, Troy O; Mayer, Lawrence D; Bally, Marcel B

2004-01-15

There is an opportunity to augment the therapeutic potential of drug combinations through use of drug delivery technology. This report summarizes data obtained using a novel liposomal formulation with coencapsulated doxorubicin and vincristine. The rationale for selecting these drugs is due in part to the fact that liposomal formulations of doxorubicin and vincristine are being separately evaluated as components of drug combinations. Doxorubicin and vincristine were coencapsulated into liposomes using two distinct methods of drug loading. A manganese-based drug loading procedure, which relies on drug complexation with a transition metal, was used to encapsulate doxorubicin. Subsequently the ionophore A23187 was added to induce formation of a pH gradient, which promoted vincristine encapsulation. Plasma elimination studies in mice indicated that the drug:drug ratio before injection [4:1 doxorubicin:vincristine (wt:wt ratio)] changed to 20:1 at the 24-h time point, indicative of more rapid release of vincristine from the liposomes than doxorubicin. Efficacy studies completed in MDA MB-435/LCC6 tumor-bearing mice suggested that at the maximum tolerated dose, the coencapsulated formulation was therapeutically no better than liposomal vincristine. This result was explained in part by in vitro cytotoxicity studies evaluating doxorubicin and vincristine combinations analyzed using the Chou and Talalay median effect principle. These data clearly indicated that simultaneous addition of vincristine and doxorubicin resulted in pronounced antagonism. These results emphasize that in vitro drug combination screens can be used to predict whether a coformulated drug combination will act in an antagonistic or synergistic manner.

Does mechanism of drug action matter to inform rational polytherapy in epilepsy?

PubMed

Giussani, Giorgia; Beghi, Ettore

2013-05-01

When monotherapy for epilepsy fails, add-on therapy is an alternative option. There are several possible antiepileptic drug combinations based on their different and multiple mechanisms of action and pharmacokinetic interactions. However, only when benefits of drug combinations outweigh the harms, polytherapy can be defined as "rational". In the past 20 years, second generation AEDs have been marketed, some of which have better defined mechanisms of action and better pharmacokinetic profile. The mechanisms of action of AEDs involve, among others, blockade of voltage-gated sodium channels, blockade of voltage-gated calcium channel, activation of the ionotropic GABAA receptor and increase of GABA levels at the synaptic cleft, blockade of glutamate receptors, binding to synaptic vesicle protein 2A, and opening of KCNQ (Kv7) potassium channels. Aim of this review was to examine published reports on AEDs combinations in animal models and humans focusing on mechanisms of action and pharmacokinetic interactions. Studies in animals have shown that AED combinations are more effective when using drugs with different mechanisms of action. The most effective combination was found using a drug with a single mechanism of action and another with multiple mechanisms of action. In humans some combinations between a blocker of voltage-gated sodium channels and a drug with multiple mechanisms of action may be synergistic. Future studies are necessary to better define rational combinations and complementary mechanisms of action, considering also pharmacokinetic interactions and measures of toxicity and not only drug efficacy.

Doxorubicin-Loaded Nanobubbles Combined with Extracorporeal Shock Waves: Basis for a New Drug Delivery Tool in Anaplastic Thyroid Cancer.

PubMed

Marano, Francesca; Argenziano, Monica; Frairia, Roberto; Adamini, Aloe; Bosco, Ornella; Rinella, Letizia; Fortunati, Nicoletta; Cavalli, Roberta; Catalano, Maria Graziella

2016-05-01

No standard chemotherapy is available for anaplastic thyroid cancer (ATC). Drug-loaded nanobubbles (NBs) are a promising innovative anticancer drug formulation, and combining them with an externally applied trigger may further control drug release at the target region. Extracorporeal shock waves (ESWs) are acoustic waves widely used in urology and orthopedics, with no side effects. The aim of the present work was to combine ESWs and new doxorubicin-loaded glycol chitosan NBs in order to target doxorubicin and enhance its antitumor effect in ATC cell lines. CAL-62 and 8305C cells were treated with empty NBs, fluorescent NBs, free doxorubicin, and doxorubicin-loaded NBs in the presence or in the absence of ESWs. NB entrance was evaluated by fluorescence microscopy and flow cytofluorimetry. Cell viability was assessed by Trypan Blue exclusion and WST-1 proliferation assays. Doxorubicin intracellular content was measured by high-performance liquid chromatography. Treatment with empty NBs and ESWs, even in combination, was safe, as cell viability and growth were not affected. Loading NBs with doxorubicin and combining them with ESWs generated the highest cytotoxic effect, resulting in drug GI50 reduction of about 40%. Mechanistically, ESWs triggered intracellular drug release from NBs, resulting in the highest nuclear drug content. Combined treatment with doxorubicin-loaded NBs and ESWs is a promising drug delivery tool for ATC treatment with the possibility of using lower doxorubicin doses and thus limiting its systemic side effects.

Synergistic Effect of Curcumin in Combination with Anticancer Agents in Human Retinoblastoma Cancer Cell Lines.

PubMed

Sreenivasan, Seethalakshmi; Krishnakumar, Subramanian

2015-01-01

Curcumin (diferuloylmethane), a phenolic compound obtained from the rhizome of the herb Curcuma longa, is known to have anti-proliferative and anti-tumor properties. In this study, we evaluated the cytotoxic effect of curcumin alone and in combination with individual drugs like carboplatin, etoposide, or vincristine in a human retinoblastoma (RB) cancer cell line. A drug-drug interaction was analyzed using the median effect/isobologram method and combination index values were used to characterize the interaction as synergistic or additive. We also performed the apoptosis and cell-cycle kinetics study with single drugs in combination with curcumin in a human RB cell lines (Y79 and Weri-Rb1). Curcumin caused concentration-dependent decrease in cell proliferation, cell kinetics, and also induced apoptosis in both the RB cell lines. When combination of curcumin with individual drugs like carboplatin or etoposide or vincristine was treated on to RB cells, both cell viability and cell cycling were reduced and increased apoptosis was noted, in comparison with single drug treatment. These effects were significant in both the cell lines, indicating the ability of curcumin to increase the sensitivity of RB cells to chemotherapy drugs. Our in vitro findings showed that the combination of curcumin with single drug treatment showed marked synergistic inhibitory effect against RB cell lines. These results suggest that curcumin can be used as a modulator which may have a potential therapeutic value for the treatment of RB cancer patients.

Magnetic nanoparticle-conjugated polymeric micelles for combined hyperthermia and chemotherapy

NASA Astrophysics Data System (ADS)

Kim, Hyun-Chul; Kim, Eunjoo; Jeong, Sang Won; Ha, Tae-Lin; Park, Sang-Im; Lee, Se Guen; Lee, Sung Jun; Lee, Seung Woo

2015-10-01

Magnetic nanoparticle-conjugated polymeric micelles (MNP-PMs) consisting of poly(ethylene glycol)-poly(lactide) (PEG-PLA) and iron oxide nanoparticles were prepared and used as nanocarriers for combined hyperthermia and chemotherapy. Doxorubicin (DOX) was encapsulated in MNP-PMs, and an alternating magnetic field (AMF) resulted in an increase to temperature within a suitable range for inducing hyperthermia and a higher rate of drug release than observed without AMF. In vitro cytotoxicity and hyperthermia experiments were carried out using human lung adenocarcinoma A549 cells. When MNP-PMs encapsulated with an anticancer drug were used to treat A549 cells in combination with hyperthermia under AMF, 78% of the cells were killed by the double effects of heat and the drug, and the combination was more effective than either chemotherapy or hyperthermia treatment alone. Therefore, MNP-PMs encapsulated with an anticancer drug show potential for combined chemotherapy and hyperthermia.Magnetic nanoparticle-conjugated polymeric micelles (MNP-PMs) consisting of poly(ethylene glycol)-poly(lactide) (PEG-PLA) and iron oxide nanoparticles were prepared and used as nanocarriers for combined hyperthermia and chemotherapy. Doxorubicin (DOX) was encapsulated in MNP-PMs, and an alternating magnetic field (AMF) resulted in an increase to temperature within a suitable range for inducing hyperthermia and a higher rate of drug release than observed without AMF. In vitro cytotoxicity and hyperthermia experiments were carried out using human lung adenocarcinoma A549 cells. When MNP-PMs encapsulated with an anticancer drug were used to treat A549 cells in combination with hyperthermia under AMF, 78% of the cells were killed by the double effects of heat and the drug, and the combination was more effective than either chemotherapy or hyperthermia treatment alone. Therefore, MNP-PMs encapsulated with an anticancer drug show potential for combined chemotherapy and hyperthermia. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04130a

[Prevalence of potential drug interactions with azithromycin in Colombia, 2012-2013].

PubMed

Machado-Alba, Jorge E; Martínez-Pulgarín, Dayron F; Gómez-Suta, Daniela

2015-05-01

Objective To determine the prevalence of potential drug interactions between azithromycin and different IA and III antiarrhythmic groups in a national database of drug prescriptions in 2012-2013. Methods Retrospective study based on a population database of medicine dispensation. Data from patients who received azithromycin between January 1, 2012 and June 30, 2013 were extracted along with data from patients who received azithromycin in combination with other medications shown to cause heart arrhythmias when used concomitantly. Frequencies and proportions were established. Results 13 859 patients receiving azithromycin alone or in combination with other drugs were identified. The average time of use was 4.5 ± 0.9 days. A total of 702 patients (5.1 %) received azithromycin plus 19 other potentially risky drugs. The most frequently associated were loratadine (77.1 %), diphenhydramine (16.5 %) and amitriptyline (8.1 %). Combinations with a single drug were the most frequent (n=533, 75.9 %), predominantly azithromycin+loratadine. The maximum number of combined drugs was six (n=2, 0.3 %). Conclusions Identification of drug prescriptions through population databases is an effective way to find potential drug interactions. The frequency of potential interactions between azithromycin and other drugs is common in Colombian patients. Future research should assess the risk of occurrence of adverse cardiac events.

Anesthetic efficacy of ketamine-diazepam, ketamine-xylazine, and ketamine-acepromazine in Caspian Pond turtles (Mauremys caspica).

PubMed

Adel, Milad; Sadegh, Amin Bigham; Arizza, Vincenzo; Abbasi, Hossein; Inguglia, Luigi; Saravi, Hasan Nasrollahzadeh

2017-01-01

The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles ( Mauremys caspica ). Three groups of the Caspian Pond turtles ( n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine-diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine-acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine-xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) were injected intramuscularly. The onset times of anesthetization and the recovery time were measured. Statistical analysis of the data was performed using one-way analysis of variance followed by t -tests, and P < 0.05 was considered statistically significant. There were statistically significant differences in the mean of the onset times of anesthesia and recovery time among the three drug combinations depending on the treatment used. The onset of anesthesia of the animals treated with the ketamine-diazepam combination was 60% and 42% shorter, for male and female turtles, respectively, compared to that obtained with the ketamine-acepromazine combination and 64% (male turtles) and 50% (female turtles) shorter than that obtained with the ketamine-xylazine combination. Further, the recovery time, in male turtles, was 17% shorter in animals treated with the first drug combination than those treated with the ketamine-acepromazine combination and 37% shorter than those treated with the ketamine-xylazine combination. The recovery time, in female turtles, did not seem to be significantly different among treatments. The study showed that the ketamine-diazepam drug combination is the anesthetic combination with the fastest onset time and shortest recovery time.

Synergistic combinations of antifungals and anti-virulence agents to fight against Candida albicans

PubMed Central

Cui, Jinhui; Ren, Biao; Tong, Yaojun; Dai, Huanqin; Zhang, Lixin

2015-01-01

Candida albicans, one of the pathogenic Candida species, causes high mortality rate in immunocompromised and high-risk surgical patients. In the last decade, only one new class of antifungal drug echinocandin was applied. The increased therapy failures, such as the one caused by multi-drug resistance, demand innovative strategies for new effective antifungal drugs. Synergistic combinations of antifungals and anti-virulence agents highlight the pragmatic strategy to reduce the development of drug resistant and potentially repurpose known antifungals, which bypass the costly and time-consuming pipeline of new drug development. Anti-virulence and synergistic combination provide new options for antifungal drug discovery by counteracting the difficulty or failure of traditional therapy for fungal infections. PMID:26048362

Hybrid combinations containing natural products and antimicrobial drugs that interfere with bacterial and fungal biofilms.

PubMed

Zacchino, Susana A; Butassi, Estefanía; Cordisco, Estefanía; Svetaz, Laura A

2017-12-15

Biofilms contribute to the pathogenesis of many chronic and difficult-to eradicate infections whose treatment is complicated due to the intrinsic resistance to conventional antibiotics. As a consequence, there is an urgent need for strategies that can be used for the prevention and treatment of biofilm-associated infections. The combination therapy comprising an antimicrobial drug with a low molecular weight (MW) natural product and an antimicrobial drug (antifungal or antibacterial) appeared as a good alternative to eradicate biofilms. The aims of this review were to perform a literature search on the different natural products that have showed the ability of potentiating the antibiofilm capacity of antimicrobial drugs, to analyze which are the antimicrobial drugs most used in combination, and to have a look on the microbial species most used to prepare biofilms. Seventeen papers, nine on combinations against antifungal biofilms and eight against antibacterial biofilms were collected. Within the text, the following topics have been developed: breaf history of the discovery of biofilms; stages in the development of a biofilm; the most used methodologies to assess antibiofilm-activity; the natural products with capacity of eradicating biofilms when acting alone; the combinations of low MW natural products with antibiotics or antifungal drugs as a strategy for eradicating microbial biofilms and a list of the low MW natural products that potentiate the inhibition capacity of antifungal and antibacterial drugs against biofilms. Regarding combinations against antifungal biofilms, eight over the nine collected works were carried out with in vitro studies while only one was performed with in vivo assays by using Caenorhabditis elegans nematode. All studies use biofilms of the Candida genus. A 67% of the potentiators were monoterpenes and sesquiterpenes and six over the nine works used FCZ as the antifungal drug. The activity of AmpB and Caspo was enhanced in one and two works respectively. Regarding combinations against bacterial biofilms, in vitro studies were performed in all works by using several different methods of higher variety than the used against fungal biofilms. Biofilms of both the gram (+) and gram (-) bacteria were prepared, although biofilm of Staphylococcus spp. were the most used in the collected works. Among the discovered potentiators of antibacterial drugs, 75% were terpenes, including mono, di- and triterpenes, and, among the atibacterial drugs, several structurally diverse types were used in the combinations: aminoglycosides, β-lactams, glucopeptides and fluoroquinolones. The potentiating capacity of natural products, mainly terpenes, on the antibiofilm effect of antimicrobial drugs opens a wide range of possibilities for the combination antimicrobial therapy. More in vivo studies on combinations of natural products with antimicrobial drugs acting against biofilms are highly required to cope the difficult to treat biofilm-associated infections. Copyright © 2017 Elsevier GmbH. All rights reserved.

Subretinal fluid levels of topical, oral, and combined administered ciprofloxacin in humans

PubMed Central

Cekic, O.; Batman, C.; Yasar, U.; Basci, N.; Zilelioglu, O.; Bozkurt, A.

2000-01-01

AIMS—To investigate the subretinal fluid (SRF) penetration of ciprofloxacin following topical, oral, and combined administration.
METHODS—34 patients undergoing conventional retinal reattachment surgery were randomly assigned to three groups. Twelve patients received topical ciprofloxacin, 11 patients received oral ciprofloxacin, and the other 11 patients received combined drug administration. SRF drug level was measured by using high performance liquid chromatography method.
RESULTS—The highest drug concentrations of all tested modes were attained following combined administration and lowest following topical administration (p <0.001). The SRF drug concentration following oral administration was also significantly higher than that of topical administration (p <0.001). Concentrations after oral and combined administration did not differ significantly (p = 0.217).
CONCLUSIONS—Topical ciprofloxacin can penetrate SRF. Ocular bioavailability of ciprofloxacin in SRF after oral and combined administration is equivalent.

 PMID:10966968

21 CFR 333.320 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Permitted combinations of active ingredients. 333... Topical Acne Drug Products § 333.320 Permitted combinations of active ingredients. (a) Resorcinol... of the user, the revised text is set forth as follows: § 333.320 Permitted combinations of active...

21 CFR 347.20 - Permitted combinations of active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... SERVICES (CONTINUED) DRUGS FOR HUMAN USE SKIN PROTECTANT DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 347.20 Permitted combinations of active ingredients. (a) Combinations of skin...) Combinations of skin protectant and external analgesic active ingredients. Any one (two when required to be in...

Cytostatic versus cytocidal profiling of quinoline drug combinations via modified fixed-ratio isobologram analysis.

PubMed

Gorka, Alexander P; Jacobs, Lauren M; Roepe, Paul D

2013-09-18

Drug combination therapy is the frontline of malaria treatment. There is an ever-accelerating need for new, efficacious combination therapies active against drug resistant malaria. Proven drugs already in the treatment pipeline, such as the quinolines, are important components of current combination therapy and also present an attractive test bank for rapid development of new concepts. The efficacy of several drug combinations versus chloroquine-sensitive and chloroquine-resistant strains was measured using both cytostatic and cytocidal potency assays. These screens identify quinoline and non-quinoline pairs that exhibit synergy, additivity, or antagonism using the fixed-ratio isobologram method and find tafenoquine - methylene blue combination to be the most synergistic. Also, interestingly, for selected pairs, additivity, synergy, or antagonism defined by quantifying IC50 (cytostatic potency) does not necessarily predict similar behaviour when potency is defined by LD50 (cytocidal potency). These data further support an evolving new model for quinoline anti-malarials, wherein haem and haemozoin are the principle target for cytostatic activity, but may not be the only target relevant for cytocidal activity.

Synergy Testing of FDA-Approved Drugs Identifies Potent Drug Combinations against Trypanosoma cruzi

PubMed Central

Ranade, Ranae M.; Don, Robert; Buckner, Frederick S.

2014-01-01

An estimated 8 million persons, mainly in Latin America, are infected with Trypanosoma cruzi, the etiologic agent of Chagas disease. Existing antiparasitic drugs for Chagas disease have significant toxicities and suboptimal effectiveness, hence new therapeutic strategies need to be devised to address this neglected tropical disease. Due to the high research and development costs of bringing new chemical entities to the clinic, we and others have investigated the strategy of repurposing existing drugs for Chagas disease. Screens of FDA-approved drugs (described in this paper) have revealed a variety of chemical classes that have growth inhibitory activity against mammalian stage Trypanosoma cruzi parasites. Aside from azole antifungal drugs that have low or sub-nanomolar activity, most of the active compounds revealed in these screens have effective concentrations causing 50% inhibition (EC50's) in the low micromolar or high nanomolar range. For example, we have identified an antihistamine (clemastine, EC50 of 0.4 µM), a selective serotonin reuptake inhibitor (fluoxetine, EC50 of 4.4 µM), and an antifolate drug (pyrimethamine, EC50 of 3.8 µM) and others. When tested alone in the murine model of Trypanosoma cruzi infection, most compounds had insufficient efficacy to lower parasitemia thus we investigated using combinations of compounds for additive or synergistic activity. Twenty-four active compounds were screened in vitro in all possible combinations. Follow up isobologram studies showed at least 8 drug pairs to have synergistic activity on T. cruzi growth. The combination of the calcium channel blocker, amlodipine, plus the antifungal drug, posaconazole, was found to be more effective at lowering parasitemia in mice than either drug alone, as was the combination of clemastine and posaconazole. Using combinations of FDA-approved drugs is a promising strategy for developing new treatments for Chagas disease. PMID:25033456

Low-Dose Tramadol and Non-Steroidal Anti-Inflammatory Drug Combination Therapy Prevents the Transition to Chronic Low Back Pain

PubMed Central

Orita, Sumihisa; Yamauchi, Kazuyo; Suzuki, Takane; Suzuki, Miyako; Sakuma, Yoshihiro; Kubota, Go; Oikawa, Yasuhiro; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Shiga, Yasuhiro; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Takahashi, Kazuhisa; Ohtori, Seiji

2016-01-01

Study Design Retrospective study. Purpose To determine whether low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy could prevent the transition of acute low back pain to chronic low back pain. Overview of Literature Inadequately treated early low back pain transitions to chronic low back pain occur in approximately 30% of affected individuals. The administration of non-steroidal anti-inflammatory drugs is effective for treatment of low back pain in the early stages. However, the treatment of low back pain that is resistant to non-steroidal anti-inflammatory drugs is challenging. Methods Patients who presented with acute low back pain at our hospital were considered for inclusion in this study. After the diagnosis of acute low back pain, non-steroidal anti-inflammatory drug administration was started. Forty patients with a visual analog scale score of >5 for low back pain 1 month after treatment were finally enrolled. The first 20 patients were included in a non-steroidal anti-inflammatory drug group, and they continued non-steroidal anti-inflammatory drug therapy for 1 month. The next 20 patients were included in a combination group, and they received low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy for 1 month. The incidence of adverse events and the improvement in the visual analog scale score at 2 months after the start of treatment were analyzed. Results No adverse events were observed in the non-steroidal anti-inflammatory drug group. In the combination group, administration was discontinued in 2 patients (10%) due to adverse events immediately following the start of tramadol administration. At 2 months, the improvement in the visual analog scale score was greater in the combination group than in the non-steroidal anti-inflammatory drug group (p<0.001). Conclusions Low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy might decrease the incidence of adverse events and prevent the transition of acute low back pain to chronic low back pain. PMID:27559448

Enhancing Photodynamyc Therapy Efficacy by Combination Therapy: Dated, Current and Oncoming Strategies

PubMed Central

Postiglione, Ilaria; Chiaviello, Angela; Palumbo, Giuseppe

2011-01-01

Combination therapy is a common practice in many medical disciplines. It is defined as the use of more than one drug to treat the same disease. Sometimes this expression describes the simultaneous use of therapeutic approaches that target different cellular/molecular pathways, increasing the chances of killing the diseased cell. This short review is concerned with therapeutic combinations in which PDT (Photodynamyc Therapy) is the core therapeutic partner. Besides the description of the principal methods used to assess the efficacy attained by combinations in respect to monotherapy, this review describes experimental results in which PDT was combined with conventional drugs in different experimental conditions. This inventory is far from exhaustive, as the number of photosensitizers used in combination with different drugs is very large. Reports cited in this work have been selected because considered representative. The combinations we have reviewed include the association of PDT with anti-oxidants, chemotherapeutics, drugs targeting topoisomerases I and II, antimetabolites and others. Some paragraphs are dedicated to PDT and immuno-modulation, others to associations of PDT with angiogenesis inhibitors, receptor inhibitors, radiotherapy and more. Finally, a look is dedicated to combinations involving the use of natural compounds and, as new entries, drugs that act as proteasome inhibitors. PMID:24212824

Combination therapy of cancer with cancer vaccine and immune checkpoint inhibitors: A mathematical model

PubMed Central

Friedman, Avner

2017-01-01

In this paper we consider a combination therapy of cancer. One drug is a vaccine which activates dendritic cells so that they induce more T cells to infiltrate the tumor. The other drug is a checkpoint inhibitor, which enables the T cells to remain active against the cancer cells. The two drugs are positively correlated in the sense that an increase in the amount of each drug results in a reduction in the tumor volume. We consider the question whether a treatment with combination of the two drugs at certain levels is preferable to a treatment by one of the drugs alone at ‘roughly’ twice the dosage level; if that is the case, then we say that there is a positive ‘synergy’ for this combination of dosages. To address this question, we develop a mathematical model using a system of partial differential equations. The variables include dendritic and cancer cells, CD4+ and CD8+ T cells, IL-12 and IL-2, GM-CSF produced by the vaccine, and a T cell checkpoint inhibitor associated with PD-1. We use the model to explore the efficacy of the two drugs, separately and in combination, and compare the simulations with data from mouse experiments. We next introduce the concept of synergy between the drugs and develop a synergy map which suggests in what proportion to administer the drugs in order to achieve the maximum reduction of tumor volume under the constraint of maximum tolerated dose. PMID:28542574

Tumor-targeted polymeric nanostructured lipid carriers with precise ratiometric control over dual-drug loading for combination therapy in non-small-cell lung cancer.

PubMed

Liang, Yan; Tian, Baocheng; Zhang, Jing; Li, Keke; Wang, Lele; Han, Jingtian; Wu, Zimei

2017-01-01

Gemcitabine (GEM) and paclitaxel (PTX) are effective combination anticancer agents against non-small-cell lung cancer (NSCLC). At the present time, a main challenge of combination treatment is the precision of control that will maximize the combined effects. Here, we report a novel method to load GEM (hydrophilic) and PTX (hydrophobic) into simplex tumor-targeted nanostructured lipid carriers (NLCs) for accurate control of the ratio of the two drugs. We covalently preconjugated the dual drugs through a hydrolyzable ester linker to form drug conjugates. N -acetyl-d-glucosamine (NAG) is a glucose receptor-targeting ligand. We added NAG to the formation of NAG-NLCs. In general, synthesis of poly(6- O -methacryloyl-d-galactopyranose)-GEM/PTX (PMAGP-GEM/PTX) conjugates was demonstrated, and NAG-NLCs were prepared using emulsification and solvent evaporation. NAG-NLCs displayed sphericity with an average diameter of 120.3±1.3 nm, a low polydispersity index of 0.233±0.04, and accurate ratiometric control over the two drugs. A cytotoxicity assay showed that the NAG-NLCs had better antitumor activity on NSCLC cells than normal cells. There was an optimal ratio of the two drugs, exhibiting the best cytotoxicity and combinatorial effects among all the formulations we tested. In comparison with both the free-drug combinations and separately nanopackaged drug conjugates, PMAGP-GEM/PTX NAG-NLCs (3:1) exhibited superior synergism. Flow cytometry and confocal laser scanning microscopy showed that NAG-NLCs exhibited higher uptake efficiency in A549 cells via glucose receptor-mediated endocytosis. This combinatorial delivery system settles problems with ratiometric coloading of hydrophilic and hydrophobic drugs for tumor-targeted combination therapy to achieve maximal anticancer efficacy in NSCLC.

Investigating antimalarial drug interactions of emetine dihydrochloride hydrate using CalcuSyn-based interactivity calculations

PubMed Central

Matthews, Holly; Deakin, Jon; Rajab, May; Idris-Usman, Maryam

2017-01-01

The widespread introduction of artemisinin-based combination therapy has contributed to recent reductions in malaria mortality. Combination therapies have a range of advantages, including synergism, toxicity reduction, and delaying the onset of resistance acquisition. Unfortunately, antimalarial combination therapy is limited by the depleting repertoire of effective drugs with distinct target pathways. To fast-track antimalarial drug discovery, we have previously employed drug-repositioning to identify the anti-amoebic drug, emetine dihydrochloride hydrate, as a potential candidate for repositioned use against malaria. Despite its 1000-fold increase in in vitro antimalarial potency (ED50 47 nM) compared with its anti-amoebic potency (ED50 26–32 uM), practical use of the compound has been limited by dose-dependent toxicity (emesis and cardiotoxicity). Identification of a synergistic partner drug would present an opportunity for dose-reduction, thus increasing the therapeutic window. The lack of reliable and standardised methodology to enable the in vitro definition of synergistic potential for antimalarials is a major drawback. Here we use isobologram and combination-index data generated by CalcuSyn software analyses (Biosoft v2.1) to define drug interactivity in an objective, automated manner. The method, based on the median effect principle proposed by Chou and Talalay, was initially validated for antimalarial application using the known synergistic combination (atovaquone-proguanil). The combination was used to further understand the relationship between SYBR Green viability and cytocidal versus cytostatic effects of drugs at higher levels of inhibition. We report here the use of the optimised Chou Talalay method to define synergistic antimalarial drug interactivity between emetine dihydrochloride hydrate and atovaquone. The novel findings present a potential route to harness the nanomolar antimalarial efficacy of this affordable natural product. PMID:28257497

Cell cycle-tailored targeting of metastatic melanoma: Challenges and opportunities.

PubMed

Haass, Nikolas K; Gabrielli, Brian

2017-07-01

The advent of targeted therapies of metastatic melanoma, such as MAPK pathway inhibitors and immune checkpoint antagonists, has turned dermato-oncology from the "bad guy" to the "poster child" in oncology. Current targeted therapies are effective, although here is a clear need to develop combination therapies to delay the onset of resistance. Many antimelanoma drugs impact on the cell cycle but are also dependent on certain cell cycle phases resulting in cell cycle phase-specific drug insensitivity. Here, we raise the question: Have combination trials been abandoned prematurely as ineffective possibly only because drug scheduling was not optimized? Firstly, if both drugs of a combination hit targets in the same melanoma cell, cell cycle-mediated drug insensitivity should be taken into account when planning combination therapies, timing of dosing schedules and choice of drug therapies in solid tumors. Secondly, if the combination is designed to target different tumor cell subpopulations of a heterogeneous tumor, one drug effective in a particular subpopulation should not negatively impact on the other drug targeting another subpopulation. In addition to the role of cell cycle stage and progression on standard chemotherapeutics and targeted drugs, we discuss the utilization of cell cycle checkpoint control defects to enhance chemotherapeutic responses or as targets themselves. We propose that cell cycle-tailored targeting of metastatic melanoma could further improve therapy outcomes and that our real-time cell cycle imaging 3D melanoma spheroid model could be utilized as a tool to measure and design drug scheduling approaches. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In Vitro Anti-Candida Activity of Lidocaine and Nitroglycerin: Alone and Combined

PubMed Central

Palmeira-de-Oliveira, Ana; Ramos, Ana Rita; Gaspar, Carlos; Palmeira-de-Oliveira, Rita; Gouveia, Paula; Martinez-de-Oliveira, José

2012-01-01

The aim of this work was to study the anti-Candida activity of lidocaine and nitroglycerin alone and in combination. Ten Candida strains were included, corresponding to 1 collection type strain (ATCC 10231) and 9 clinical isolates: 4 C. albicans, 2 C. glabrata, 1 C. tropicalis, 1 C. krusei, and 1 C. parapsilosis. The CLSI reference M27-A3 micromethod was used to determine the anti-Candida activity of the drugs alone; minimal inhibitory and lethal concentrations were determined. The classic checkboard technique was used to determine the activity of combined drugs. Lidocaine fungicidal effect was dosedependent. Nitroglycerin exhibited a higher effect. The drugs combination resulted in a reduction of the inhibitory concentration, corresponding to an additive effect. In conclusion, both drugs exhibited an interesting anti-Candida activity. The combination of lidocaine with nitroglycerin was shown to have an additive effect against Candida spp., predicting the interest to include, in the future, these drugs in a new delivery system for the treatment of mucocutaneous candidosis. PMID:22675243

Combination Drug Therapy for Pain following Chronic Spinal Cord Injury

PubMed Central

Hama, Aldric; Sagen, Jacqueline

2012-01-01

A number of mechanisms have been elucidated that maintain neuropathic pain due to spinal cord injury (SCI). While target-based therapeutics are being developed based on elucidation of these mechanisms, treatment for neuropathic SCI pain has not been entirely satisfactory due in part to the significant convergence of neurological and inflammatory processes that maintain the neuropathic pain state. Thus, a combination drug treatment strategy, wherein several pain-related mechanism are simultaneously engaged, could be more efficacious than treatment against individual mechanisms alone. Also, by engaging several targets at once, it may be possible to reduce the doses of the individual drugs, thereby minimizing the potential for adverse side effects. Positive preclinical and clinical studies have demonstrated improved efficacy of combination drug treatment over single drug treatment in neuropathic pain of peripheral origin, and perhaps such combinations could be utilized for neuropathic SCI pain. At the same time, there are mechanisms that distinguish SCI from peripheral neuropathic pain, so novel combination therapies will be needed. PMID:22550581

Combining paracetamol (acetaminophen) with nonsteroidal antiinflammatory drugs: a qualitative systematic review of analgesic efficacy for acute postoperative pain.

PubMed

Ong, Cliff K S; Seymour, Robin A; Lirk, Phillip; Merry, Alan F

2010-04-01

There has been a trend over recent years for combining a nonsteroidal antiinflammatory drug (NSAID) with paracetamol (acetaminophen) for pain management. However, therapeutic superiority of the combination of paracetamol and an NSAID over either drug alone remains controversial. We evaluated the efficacy of the combination of paracetamol and an NSAID versus either drug alone in various acute pain models. A systematic literature search of Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, and PubMed covering the period from January 1988 to June 2009 was performed to identify randomized controlled trials in humans that specifically compared combinations of paracetamol with various NSAIDs versus at least 1 of these constituent drugs. Identified studies were stratified into 2 groups: paracetamol/NSAID combinations versus paracetamol or NSAIDs. We analyzed pain intensity scores and supplemental analgesic requirements as primary outcome measures. In addition, each study was graded for quality using a validated scale. Twenty-one human studies enrolling 1909 patients were analyzed. The NSAIDs used were ibuprofen (n = 6), diclofenac (n = 8), ketoprofen (n = 3), ketorolac (n = 1), aspirin (n = 1), tenoxicam (n = 1), and rofecoxib (n = 1). The combination of paracetamol and NSAID was more effective than paracetamol or NSAID alone in 85% and 64% of relevant studies, respectively. The pain intensity and analgesic supplementation was 35.0% +/- 10.9% and 38.8% +/- 13.1% lesser, respectively, in the positive studies for the combination versus paracetamol group, and 37.7% +/- 26.6% and 31.3% +/- 13.4% lesser, respectively, in the positive studies for the combination versus the NSAID group. No statistical difference in median quality scores was found between experimental groups. Current evidence suggests that a combination of paracetamol and an NSAID may offer superior analgesia compared with either drug alone.

Synergy against drug-resistant HIV-1 with the microbicide antiretrovirals, dapivirine and tenofovir, in combination.

PubMed

Schader, Susan M; Colby-Germinario, Susan P; Schachter, Jordana R; Xu, Hongtao; Wainberg, Mark A

2011-08-24

To evaluate the candidate antiretroviral microbicide compounds, dapivirine (DAP) and tenofovir (TFV), alone and in combination against the transmission of wild-type and nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant HIV-1 from different subtypes. We determined single-drug efficacy of the RTIs, DAP and TFV, against subtype B and non-B wild-type and NNRTI-resistant HIV-1 in vitro. To assess breadth of activity, compounds were tested alone and in combination against wild-type and NNRTI-resistant subtype C primary HIV-1 isolates and complimentary clonal HIV-1 from subtypes B, C and CRF02_AG to control for viral variation. Early infection was quantified by counting light units emitted from TZM-bl cells less than 48-h postinfection. Combination ratios were based on drug inhibitory concentrations (IC(50)s) and combined effects were determined by calculating combination indices. Both candidate microbicide antiretrovirals demonstrated potent anti-NNRTI-resistant HIV-1 activity in vitro, albeit the combination protected better than the single-drug treatments. Of particular interest, the DAP with TFV combination exhibited synergy (50% combination index, CI(50) = 0.567) against subtype C NNRTI-resistant HIV-1, whereas additivity (CI(50) = 0.987) was observed against the wild-type counterpart from the same patient. The effect was not compounded by the presence of subdominant viral fractions, as experiments using complimentary clonal subtype C wild-type (CI(50) = 0.968) and NNRTI-resistant (CI(50) = 0.672) HIV-1, in lieu of the patient quasispecies, gave similar results. This study supports the notion that antiretroviral drug combinations may retain antiviral activity against some drug-resistant HIV-1 despite subtype classification and quasispecies diversity.

A predictive pharmacokinetic-pharmacodynamic model of tumor growth kinetics in xenograft mice after administration of anticancer agents given in combination.

PubMed

Terranova, Nadia; Germani, Massimiliano; Del Bene, Francesca; Magni, Paolo

2013-08-01

In clinical oncology, combination treatments are widely used and increasingly preferred over single drug administrations. A better characterization of the interaction between drug effects and the selection of synergistic combinations represent an open challenge in drug development process. To this aim, preclinical studies are routinely performed, even if they are only qualitatively analyzed due to the lack of generally applicable mathematical models. This paper presents a new pharmacokinetic-pharmacodynamic model that, starting from the well-known single agent Simeoni TGI model, is able to describe tumor growth in xenograft mice after the co-administration of two anticancer agents. Due to the drug action, tumor cells are divided in two groups: damaged and not damaged ones. The damaging rate has two terms proportional to drug concentrations (as in the single drug administration model) and one interaction term proportional to their product. Six of the eight pharmacodynamic parameters assume the same value as in the corresponding single drug models. Only one parameter summarizes the interaction, and it can be used to compute two important indexes that are a clear way to score the synergistic/antagonistic interaction among drug effects. The model was successfully applied to four new compounds co-administered with four drugs already available on the market for the treatment of three different tumor cell lines. It also provided reliable predictions of different combination regimens in which the same drugs were administered at different doses/schedules. A good and quantitative measurement of the intensity and nature of interaction between drug effects, as well as the capability to correctly predict new combination arms, suggest the use of this generally applicable model for supporting the experiment optimal design and the prioritization of different therapies.

Posaconazole exhibits in vitro and in vivo synergistic antifungal activity with caspofungin or FK506 against Candida albicans.

PubMed

Chen, Ying-Lien; Lehman, Virginia N; Averette, Anna F; Perfect, John R; Heitman, Joseph

2013-01-01

The object of this study was to test whether posaconazole, a broad-spectrum antifungal agent inhibiting ergosterol biosynthesis, exhibits synergy with the β-1,3 glucan synthase inhibitor caspofungin or the calcineurin inhibitor FK506 against the human fungal pathogen Candida albicans. Although current drug treatments for Candida infection are often efficacious, the available antifungal armamentarium may not be keeping pace with the increasing incidence of drug resistant strains. The development of drug combinations or novel antifungal drugs to address emerging drug resistance is therefore of general importance. Combination drug therapies are employed to treat patients with HIV, cancer, or tuberculosis, and has considerable promise in the treatment of fungal infections like cryptococcal meningitis and C. albicans infections. Our studies reported here demonstrate that posaconazole exhibits in vitro synergy with caspofungin or FK506 against drug susceptible or resistant C. albicans strains. Furthermore, these combinations also show in vivo synergy against C. albicans strain SC5314 and its derived echinocandin-resistant mutants, which harbor an S645Y mutation in the CaFks1 β-1,3 glucan synthase drug target, suggesting potential therapeutic applicability for these combinations in the future.

Herb-drug interactions.

PubMed

Fugh-Berman, A

2000-01-08

Concurrent use of herbs may mimic, magnify, or oppose the effect of drugs. Plausible cases of herb-drug interactions include: bleeding when warfarin is combined with ginkgo (Ginkgo biloba), garlic (Allium sativum), dong quai (Angelica sinensis), or danshen (Salvia miltiorrhiza); mild serotonin syndrome in patients who mix St John's wort (Hypericum perforatum) with serotonin-reuptake inhibitors; decreased bioavailability of digoxin, theophylline, cyclosporin, and phenprocoumon when these drugs are combined with St John's wort; induction of mania in depressed patients who mix antidepressants and Panax ginseng; exacerbation of extrapyramidal effects with neuroleptic drugs and betel nut (Areca catechu); increased risk of hypertension when tricyclic antidepressants are combined with yohimbine (Pausinystalia yohimbe); potentiation of oral and topical corticosteroids by liquorice (Glycyrrhiza glabra); decreased blood concentrations of prednisolone when taken with the Chinese herbal product xaio chai hu tang (sho-salko-to); and decreased concentrations of phenytoin when combined with the Ayurvedic syrup shankhapushpi. Anthranoid-containing plants (including senna [Cassia senna] and cascara [Rhamnus purshiana]) and soluble fibres (including guar gum and psyllium) can decrease the absorption of drugs. Many reports of herb-drug interactions are sketchy and lack laboratory analysis of suspect preparations. Health-care practitioners should caution patients against mixing herbs and pharmaceutical drugs.

Combination therapeutics in complex diseases.

PubMed

He, Bing; Lu, Cheng; Zheng, Guang; He, Xiaojuan; Wang, Maolin; Chen, Gao; Zhang, Ge; Lu, Aiping

2016-12-01

The biological redundancies in molecular networks of complex diseases limit the efficacy of many single drug therapies. Combination therapeutics, as a common therapeutic method, involve pharmacological intervention using several drugs that interact with multiple targets in the molecular networks of diseases and may achieve better efficacy and/or less toxicity than monotherapy in practice. The development of combination therapeutics is complicated by several critical issues, including identifying multiple targets, targeting strategies and the drug combination. This review summarizes the current achievements in combination therapeutics, with a particular emphasis on the efforts to develop combination therapeutics for complex diseases. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Mathematical Modelling and Analysis of the Tumor Treatment Regimens with Pulsed Immunotherapy and Chemotherapy

PubMed Central

Pang, Liuyong; Shen, Lin; Zhao, Zhong

2016-01-01

To begin with, in this paper, single immunotherapy, single chemotherapy, and mixed treatment are discussed, and sufficient conditions under which tumor cells will be eliminated ultimately are obtained. We analyze the impacts of the least effective concentration and the half-life of the drug on therapeutic results and then find that increasing the least effective concentration or extending the half-life of the drug can achieve better therapeutic effects. In addition, since most types of tumors are resistant to common chemotherapy drugs, we consider the impact of drug resistance on therapeutic results and propose a new mathematical model to explain the cause of the chemotherapeutic failure using single drug. Based on this, in the end, we explore the therapeutic effects of two-drug combination chemotherapy, as well as mixed immunotherapy with combination chemotherapy. Numerical simulations indicate that combination chemotherapy is very effective in controlling tumor growth. In comparison, mixed immunotherapy with combination chemotherapy can achieve a better treatment effect. PMID:26997972

Mathematical Modelling and Analysis of the Tumor Treatment Regimens with Pulsed Immunotherapy and Chemotherapy.

PubMed

Pang, Liuyong; Shen, Lin; Zhao, Zhong

2016-01-01

To begin with, in this paper, single immunotherapy, single chemotherapy, and mixed treatment are discussed, and sufficient conditions under which tumor cells will be eliminated ultimately are obtained. We analyze the impacts of the least effective concentration and the half-life of the drug on therapeutic results and then find that increasing the least effective concentration or extending the half-life of the drug can achieve better therapeutic effects. In addition, since most types of tumors are resistant to common chemotherapy drugs, we consider the impact of drug resistance on therapeutic results and propose a new mathematical model to explain the cause of the chemotherapeutic failure using single drug. Based on this, in the end, we explore the therapeutic effects of two-drug combination chemotherapy, as well as mixed immunotherapy with combination chemotherapy. Numerical simulations indicate that combination chemotherapy is very effective in controlling tumor growth. In comparison, mixed immunotherapy with combination chemotherapy can achieve a better treatment effect.

CImbinator: a web-based tool for drug synergy analysis in small- and large-scale datasets.

PubMed

Flobak, Åsmund; Vazquez, Miguel; Lægreid, Astrid; Valencia, Alfonso

2017-08-01

Drug synergies are sought to identify combinations of drugs particularly beneficial. User-friendly software solutions that can assist analysis of large-scale datasets are required. CImbinator is a web-service that can aid in batch-wise and in-depth analyzes of data from small-scale and large-scale drug combination screens. CImbinator offers to quantify drug combination effects, using both the commonly employed median effect equation, as well as advanced experimental mathematical models describing dose response relationships. CImbinator is written in Ruby and R. It uses the R package drc for advanced drug response modeling. CImbinator is available at http://cimbinator.bioinfo.cnio.es , the source-code is open and available at https://github.com/Rbbt-Workflows/combination_index . A Docker image is also available at https://hub.docker.com/r/mikisvaz/rbbt-ci_mbinator/ . asmund.flobak@ntnu.no or miguel.vazquez@cnio.es. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

DeepSynergy: predicting anti-cancer drug synergy with Deep Learning

PubMed Central

Preuer, Kristina; Lewis, Richard P I; Hochreiter, Sepp; Bender, Andreas; Bulusu, Krishna C; Klambauer, Günter

2018-01-01

Abstract Motivation While drug combination therapies are a well-established concept in cancer treatment, identifying novel synergistic combinations is challenging due to the size of combinatorial space. However, computational approaches have emerged as a time- and cost-efficient way to prioritize combinations to test, based on recently available large-scale combination screening data. Recently, Deep Learning has had an impact in many research areas by achieving new state-of-the-art model performance. However, Deep Learning has not yet been applied to drug synergy prediction, which is the approach we present here, termed DeepSynergy. DeepSynergy uses chemical and genomic information as input information, a normalization strategy to account for input data heterogeneity, and conical layers to model drug synergies. Results DeepSynergy was compared to other machine learning methods such as Gradient Boosting Machines, Random Forests, Support Vector Machines and Elastic Nets on the largest publicly available synergy dataset with respect to mean squared error. DeepSynergy significantly outperformed the other methods with an improvement of 7.2% over the second best method at the prediction of novel drug combinations within the space of explored drugs and cell lines. At this task, the mean Pearson correlation coefficient between the measured and the predicted values of DeepSynergy was 0.73. Applying DeepSynergy for classification of these novel drug combinations resulted in a high predictive performance of an AUC of 0.90. Furthermore, we found that all compared methods exhibit low predictive performance when extrapolating to unexplored drugs or cell lines, which we suggest is due to limitations in the size and diversity of the dataset. We envision that DeepSynergy could be a valuable tool for selecting novel synergistic drug combinations. Availability and implementation DeepSynergy is available via www.bioinf.jku.at/software/DeepSynergy. Contact klambauer@bioinf.jku.at Supplementary information Supplementary data are available at Bioinformatics online. PMID:29253077

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

PubMed

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

2017-02-21

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

Two is better than one; toward a rational design of combinatorial therapy.

PubMed

Chen, Sheng-Hong; Lahav, Galit

2016-12-01

Drug combination is an appealing strategy for combating the heterogeneity of tumors and evolution of drug resistance. However, the rationale underlying combinatorial therapy is often not well established due to lack of understandings of the specific pathways responding to the drugs, and their temporal dynamics following each treatment. Here we present several emerging trends in harnessing properties of biological systems for the optimal design of drug combinations, including the type of drugs, specific concentration, sequence of addition and the temporal schedule of treatments. We highlight recent studies showing different approaches for efficient design of drug combinations including single-cell signaling dynamics, adaption and pathway crosstalk. Finally, we discuss novel and feasible approaches that can facilitate the optimal design of combinatorial therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synergistic Combinations of Multiple Chemotherapeutic Agents in High Capacity Poly(2-oxazoline) Micelles

PubMed Central

Han, Yingchao; He, Zhijian; Schulz, Anita; Bronich, Tatiana K.; Jordan, Rainer; Luxenhofer, Robert; Kabanov, Alexander V.

2012-01-01

Many effective drugs for cancer treatment are poorly water-soluble. In combination chemotherapy, needed excipients in additive formulations are often toxic and restrict their applications in clinical intervention. Here, we report on amphiphilic poly(2-oxazoline)s (POx) micelles as a promising high capacity delivery platform for multi-drug cancer chemotherapy. A variety of binary and ternary drugs combinations of paclitaxel (PTX), docetaxel (DTX), 17-allylamino-17-demethoxygeldanamycin (17-AAG), etoposide (ETO) and bortezomib (BTZ) were solubilized in defined polymeric micelles achieving unprecedented high total loading capacities of up to 50 wt.% drug per final formulation. Multi-drug loaded POx micelles showed enhanced stability in comparison to single-drug loaded micelles. Drug ratio dependent synergistic cytotoxicity of micellar ETO/17-AAG was observed in MCF-7 cancer cells and of micellar BTZ/17-AAG in MCF-7, PC3, MDA-MB-231 and HepG2 cells. PMID:22681126

Suppression of HLA Expression by Lentivirus-mediated Gene Transfer of siRNA Cassettes and In Vivo Chemoselection to Enhance Hematopoietic Stem Cell Transplantation

PubMed Central

Hacke, Katrin; Falahati, Rustom; Flebbe-Rehwaldt, Linda; Kasahara, Noriyuki; Gaensler, Karin M. L.

2010-01-01

Current approaches for hematopoietic stem cell (HSC) and organ transplantation are limited by donor and host-mediated immune responses to allo-antigens. Application of these therapies is limited by the toxicity of preparative and post-transplant immunosuppressive regimens and a shortage of appropriate HLA-matched donors. We have been exploring two complementary approaches for genetically modifying donor cells that achieve long-term suppression of cellular proteins that elicit host immune responses to mismatched donor antigens, and provide a selective advantage to genetically engineered donor cells after transplantation. The first approach is based on recent advances that make feasible targeted down-regulation of HLA expression. Suppression of HLA expression could help to overcome limitations imposed by extensive HLA polymorphisms that restrict the availability of suitable donors. Accordingly, we have recently investigated whether knockdown of HLA by RNA interference (RNAi) enables allogeneic cells to evade immune recognition. For efficient and stable delivery of short hairpin-type RNAi constructs (shRNA), we employed lentivirus-based gene transfer vectors that integrate into genomic DNA, thereby permanently modifying transduced donor cells. Lentivirus-mediated delivery of shRNA targeting pan-Class I and allele-specific HLA achieved efficient and dose-dependent reduction in surface expression of HLA in human cells, and enhanced resistance to allo-reactive T lymphocyte-mediated cytotoxicity, while avoiding non-MHC restricted killing. Complementary strategies for genetic engineering of HSC that would provide a selective advantage for transplanted donor cells and enable successful engraftment with less toxic preparative and immunosuppressive regimens would increase the numbers of individuals to whom HLA suppression therapy could be offered. Our second strategy is to provide a mechanism for in vivo selection of genetically modified HSC and other donor cells. We have uniquely combined transplantation during the neonatal period, when tolerance may be more readily achieved, with a positive selection strategy for in vivo amplification of drug-resistant donor HSC. This model system enables the evaluation of mechanisms of tolerance induction to neo-antigens, and allogeneic stem cells during immune ontogeny. HSC are transduced ex vivo by lentivirus-mediated gene transfer of P140K-O6-methylguanine-methyltransferase (MGMTP140K). The MGMTP140K DNA repair enzyme confers resistance to benzylguanine, an inhibitor of endogenous MGMT, and to chloroethylating agents such as BCNU. In vivo chemoselection enables enrichment of donor cells at the stem cell level. Using complementary approaches of in vivo chemoselection and RNAi-induced silencing of HLA expression may enable the generation of histocompatibility-enhanced, and eventually, perhaps “universally” compatible cellular grafts. PMID:19048410

Mangiferin enhances the sensitivity of human multiple myeloma cells to anticancer drugs through suppression of the nuclear factor κB pathway.

PubMed

Takeda, Tomoya; Tsubaki, Masanobu; Kino, Toshiki; Kawamura, Ayako; Isoyama, Shota; Itoh, Tatsuki; Imano, Motohiro; Tanabe, Genzoh; Muraoka, Osamu; Matsuda, Hideaki; Satou, Takao; Nishida, Shozo

2016-06-01

Multiple myeloma (MM) is still an incurable hematological malignancy with a 5-year survival rate of ~35%, despite the use of various treatment options. The nuclear factor κB (NF-κB) pathway plays a crucial role in the pathogenesis of MM. Thus, inhibition of the NF-κB pathway is a potential target for the treatment of MM. In a previous study, we showed that mangiferin suppressed the nuclear translocation of NF-κB. However, the treatment of MM involves a combination of two or three drugs. In this study, we examined the effect of the combination of mangiferin and conventional anticancer drugs in an MM cell line. We showed that the combination of mangiferin and an anticancer drug decreased the viability of MM cell lines in comparison with each drug used separately. The decrease in the combination of mangiferin and an anticancer drug induced cell viability was attributed to increase the expression of p53 and Noxa and decreases the expression of XIAP, survivin, and Bcl-xL proteins via inhibition of NF-κB pathway. In addition, the combination treatment caused the induction of apoptosis, activation of caspase-3 and the accumulation of the cells in the sub-G1 phase of the cell cycle. Our findings suggest that the combination of mangiferin and an anticancer drug could be used as a new regime for the treatment of MM.

Development and validation of a general approach to predict and quantify the synergism of anti-cancer drugs using experimental design and artificial neural networks.

PubMed

Pivetta, Tiziana; Isaia, Francesco; Trudu, Federica; Pani, Alessandra; Manca, Matteo; Perra, Daniela; Amato, Filippo; Havel, Josef

2013-10-15

The combination of two or more drugs using multidrug mixtures is a trend in the treatment of cancer. The goal is to search for a synergistic effect and thereby reduce the required dose and inhibit the development of resistance. An advanced model-free approach for data exploration and analysis, based on artificial neural networks (ANN) and experimental design is proposed to predict and quantify the synergism of drugs. The proposed method non-linearly correlates the concentrations of drugs with the cytotoxicity of the mixture, providing the possibility of choosing the optimal drug combination that gives the maximum synergism. The use of ANN allows for the prediction of the cytotoxicity of each combination of drugs in the chosen concentration interval. The method was validated by preparing and experimentally testing the combinations with the predicted highest synergistic effect. In all cases, the data predicted by the network were experimentally confirmed. The method was applied to several binary mixtures of cisplatin and [Cu(1,10-orthophenanthroline)2(H2O)](ClO4)2, Cu(1,10-orthophenanthroline)(H2O)2(ClO4)2 or [Cu(1,10-orthophenanthroline)2(imidazolidine-2-thione)](ClO4)2. The cytotoxicity of the two drugs, alone and in combination, was determined against human acute T-lymphoblastic leukemia cells (CCRF-CEM). For all systems, a synergistic effect was found for selected combinations. © 2013 Elsevier B.V. All rights reserved.

Combination therapy for malaria in Africa: hype or hope?

PubMed Central

Bloland, P. B.; Ettling, M.; Meek, S.

2000-01-01

The development of resistance to drugs poses one of the greatest threats to malaria control. In Africa, the efficacy of readily affordable antimalarial drugs is declining rapidly, while highly efficacious drugs tend to be too expensive. Cost-effective strategies are needed to extend the useful life spans of antimalarial drugs. Observations in South-East Asia on combination therapy with artemisinin derivatives and mefloquine indicate that the development of resistance to both components is slowed down. This suggests the possibility of a solution to the problem of drug resistance in Africa, where, however, there are major obstacles in the way of deploying combination therapy effectively. The rates of transmission are relatively high, a large proportion of asymptomatic infection occurs in semi-immune persons, the use of drugs is frequently inappropriate and ill-informed, there is a general lack of laboratory diagnoses, and public health systems in sub-Saharan Africa are generally weak. Furthermore, the cost of combination therapy is comparatively high. We review combination therapy as used in South-East Asia and outline the problems that have to be overcome in order to adopt it successfully in sub-Saharan Africa. PMID:11196485

Sulforaphane increases drug-mediated cytotoxicity toward cancer stem-like cells of pancreas and prostate.

PubMed

Kallifatidis, Georgios; Labsch, Sabrina; Rausch, Vanessa; Mattern, Juergen; Gladkich, Jury; Moldenhauer, Gerhard; Büchler, Markus W; Salnikov, Alexei V; Herr, Ingrid

2011-01-01

Despite intense efforts to develop treatments against pancreatic cancer, agents that cure this highly resistant and metastasizing disease are not available. Considerable attention has focused on broccoli compound sulforaphane (SF), which is suggested as combination therapy for targeting of pancreatic cancer stem cells (CSCs). However, there are concerns that antioxidative properties of SF may interfere with cytotoxic drugs-as suggested, e.g., for vitamins. Therefore we investigated a combination therapy using established pancreatic CSCs. Although cisplatin (CIS), gemcitabine (GEM), doxorubicin, 5-flurouracil, or SF effectively induced apoptosis and prevented viability, combination of a drug with SF increased toxicity. Similarly, SF potentiated the drug effect in established prostate CSCs revealing that SF enhances drug cytotoxicity also in other tumor entities. Most importantly, combined treatment intensified inhibition of clonogenicity and spheroid formation and aldehyde dehydrogenase 1 (ALDH1) activity along with Notch-1 and c-Rel expression indicating that CSC characteristics are targeted. In vivo, combination treatment was most effective and totally abolished growth of CSC xenografts and tumor-initiating potential. No pronounced side effects were observed in normal cells or mice. Our data suggest that SF increases the effectiveness of various cytotoxic drugs against CSCs without inducing additional toxicity in mice.

Biodegradable Scaffolds for Bone Regeneration Combined with Drug-Delivery Systems in Osteomyelitis Therapy

PubMed Central

Dorati, Rossella; DeTrizio, Antonella; Modena, Tiziana; Conti, Bice; Benazzo, Francesco; Gastaldi, Giulia; Genta, Ida

2017-01-01

A great deal of research is ongoing in the area of tissue engineering (TE) for bone regeneration. A possible improvement in restoring damaged tissues involves the loading of drugs such as proteins, genes, growth factors, antibiotics, and anti-inflammatory drugs into scaffolds for tissue regeneration. This mini-review is focused on the combination of the local delivery of antibiotic agents with bone regenerative therapy for the treatment of a severe bone infection such as osteomyelitis. The review includes a brief explanation of scaffolds for bone regeneration including scaffolds characteristics and types, a focus on severe bone infections (especially osteomyelitis and its treatment), and a literature review of local antibiotic delivery by the combination of scaffolds and drug-delivery systems. Some examples related to published studies on gentamicin sulfate-loaded drug-delivery systems combined with scaffolds are discussed, and future perspectives are highlighted. PMID:29231857

Determining animal drug combinations based on efficacy and safety.

PubMed

Kratzer, D D; Geng, S

1986-08-01

A procedure for deriving drug combinations for animal health is used to derive an optimal combination of 200 mg of novobiocin and 650,000 IU of penicillin for nonlactating cow mastitis treatment. The procedure starts with an estimated second order polynomial response surface equation. That surface is translated into a probability surface with contours called isoprobs. The isoprobs show drug amounts that have equal probability to produce maximal efficacy. Safety factors are incorporated into the probability surface via a noncentrality parameter that causes the isoprobs to expand as safety decreases, resulting in lower amounts of drug being used.

Drug combination may be highly effective in recurrent ovarian cancer

Cancer.gov

Significant improvement with the use of a combination drug therapy for recurrent ovarian cancer was reported at the annual meeting of the American Society of Clinical Oncology meeting in Chicago. The trial compared the activity of a combination of the dru

Auditing Analgesic Use in Post-operative Setting in a Teaching Hospital

PubMed Central

Bathini, Prapthi

2015-01-01

Introduction: Managing postoperative pain efficiently is one important therapeutic challenge in the hospitals. Combination use of analgesics is in vogue, where in drugs from the opioid and non-opioid group are given synergistically. The aim of this study is to audit the use of different analgesics on the first postoperative day. Effort has been made to look into the drug or drug combinations used and other factors associated with their use. Materials and Methods: Retrospective, cross sectional observational study was conducted over a period of 11 months in a tertiary care teaching hospital at Hyderabad with approval from institutional ethics committee. Medical records of 649 patients on the first postoperative day were analysed for analgesics by various indicators. Results: Average number of drugs per encounter was 4.23. Percentage of patients prescribed drugs from national essential drug list/WHO was 81.94%. Most common analgesic (monotherapy) prescribed was tramadol followed by diclofenac and the most common combination drugs prescribed were tramadol+Paracetamol. The most common route of administration was intravenous. All the drugs except piroxicam, were in the lower limit of the recommended daily dose. Conclusion: The present study gives an idea of the overall pattern of analgesic drug use in postoperative patients. The drug combinations used, the most common single use drug can be made out. The health professionals can be encouraged to prescribe by generic name and from the National List of Essential Medicines NLEMs. PMID:26023565

Comparative study between atorvastatin and losartan on high fat diet-induced type 2 diabetes mellitus in rats.

PubMed

Mourad, Ahmed A; Heeba, Gehan H; Taye, Ashraf; El-Moselhy, Mohamed A

2013-10-01

Obesity is often associated with chronic inflammatory state which contributes to the development of insulin resistance (IR) and type 2 diabetes mellitus (T2DM). This study investigated the effects of single and combined administration of atorvastatin (ATOR, lipid-lowering drug) and losartan (LOS, angiotensin receptor antagonist) on metabolic disorders and inflammatory status that are implicated in the development of T2DM with the use of pioglitazone (PIO) as a standard antidiabetic drug. T2DM was induced in male rats by high-fat diet (HFD) feeding for 16 weeks. Oral administrations of ATOR (10 mg/kg), LOS (20 mg/kg), PIO (3 mg/kg), their binary combinations, or vehicle were started in the last 4 weeks. Fasting serum glucose, oral glucose tolerance, fasting serum insulin, IR, serum lipid profile, serum TNF-α and body composition index were determined. Results showed that all drugs and their combinations had positive impact effect on all measured parameters, and better results were achieved from binary drug combinations than administration of each drug alone. Combination of PIO with either ATOR or LOS provided better improvements on T2DM-associated metabolic abnormalities and inflammatory status with respect to each drug alone. However, the most pronounced effects of drugs and their combinations regarding the above parameters were attributed to LOS + PIO combination. In conclusion, this study indicates that combination of ATOR + PIO and, in particular, LOS + PIO can be used as promising effective therapies in the management of HFD-induced T2DM. This concept may be attributed to the combined effects of the respective monotherapies to improve lipid profile, insulin sensitivity, and TNF-α level. © 2012 The Authors Fundamental and Clinical Pharmacology © 2012 Société Française de Pharmacologie et de Thérapeutique.

[Rational combinations of antiepileptic drugs for refractory epilepsy].

PubMed

Yoshino, Aihide

2011-04-01

Although epilepsy surgery is most effective for patients with intractable epilepsy, a majority of them is not eligible for the surgery. Most of patients with refractory epilepsy are eventually treated with polypharmacy in hope of seizure control. Therefore, rational combinations of antiepileptic drugs are needed to control intractable seizures. Drug combinations should be rationally chosen based on the evidence of synergic efficacy and on avoidance of neurotoxicity. Several clinical studies suggest that the combination of valproate with lamotrigine has synergic antiepileptic effect. It has also been reported that the combination of carbamazepine with lamotrigine paradoxically decreases efficacy and increases toxicity. Animal studies using isobolography suggest that the combinations of topiramate with lamotrigine or levetiracetam are also promising on both seizure control and neurotoxicity. Clinical research is needed to examine these combinations.

Antifungal activity of Rubus chingii extract combined with fluconazole against fluconazole-resistant Candida albicans.

PubMed

Han, Bing; Chen, Jia; Yu, Yi-qun; Cao, Yong-bing; Jiang, Yuan-ying

2016-02-01

This study aimed to investigate the antifungal activity of Rubus chingii extract in combination with fluconazole (FLC) against FLC-resistant Candida albicans 100 in vitro. A R. chingii extract and FLC-resistant C. albicans fungus suspension were prepared. The minimum inhibitory concentration and fractional inhibitory concentration index of R. chingii extract combined with FLC against C. albicans were determined, after which growth curves for C. albicans treated with R. chingii extract, FLC alone and a combination of these preparations were constructed. Additionally, the mechanisms of drug combination against C. albicans were explored by flow cytometry, gas chromatographic mass spectrometry and drug efflux pump function detection. R. chingii extract combined with FLC showed significant synergy. Flow cytometry suggested that C. albicans cells mainly arrest in G1 and S phases when they have been treated with the drug combination. The drug combination resulted in a marked decrease in the ergosterol content of the cell membrane. Additionally, efflux of Rhodamine 6G decreased with increasing concentrations of R. chingii extract. R. chingii extract combined with FLC has antifungal activity against FLC-resistant C. albicans. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

Combination chemotherapy increases cytotoxicity of multiple myeloma cells by modification of nuclear factor (NF)-κB activity

PubMed Central

Salem, Kelley; Brown, Charles O.; Schibler, Jeanine; Goel, Apollina

2012-01-01

The NF-κB signaling pathway is critical in myeloma cell proliferation, inhibition of apoptosis, and emergence of therapy resistance. The chemotherapeutic drugs, dexamethasone (Dex) and bortezomib (BTZ), are widely used in clinical protocols for multiple myeloma (MM) and inhibit the NF-κB signaling pathway by distinct mechanisms. This study evaluates the efficacy of combination therapy with Dex and BTZ and investigates the mechanistic underpinning of endogenous and therapy-induced NF-κB activation in MM. Human myeloma cells and bone marrow stromal cells (BMSCs) were used in monocultures and co-cultures to determine the cytotoxic effects of Dex and/or BTZ. Our results show that combined treatment of Dex with BTZ enhanced direct apoptosis of drug-sensitive and drug-resistant myeloma cells. In the presence of BMSCs, Dex plus BTZ combination inhibited ionizing radiation (IR)-induced interleukin (IL)-6 secretion from BMSCs and induced myeloma cytotoxicity. Mechanistically, Dex treatment increased IκBα protein and mRNA expression and compensated for BTZ-induced IκBα degradation. Dex plus BTZ combination inhibited basal and therapy-induced NF-κB activity with cytotoxicity in myeloma cells resistant to BTZ. Furthermore, combination therapy down-regulated the NF-κB targeted gene expression of IL-6 and manganese superoxide dismutase (MnSOD), which can induce chemo- and radio-resistance in MM. This study provides mechanistic rationale for combining the NF-κB-targeting drugs Dex and BTZ in myeloma therapy and supports potential combinations of these drugs with radiotherapy and additional chemotherapeutic drugs, for clinical benefit in MM. PMID:23063726

Acetaminophen and non-steroidal anti-inflammatory drugs interact with morphine and tramadol analgesia for the treatment of neuropathic pain in rats.

PubMed

Shinozaki, Tomonari; Yamada, Toshihiko; Nonaka, Takahiro; Yamamoto, Tatsuo

2015-06-01

Although non-steroidal anti-inflammatory drugs and acetaminophen have no proven efficacy against neuropathic pain, they are frequently prescribed for neuropathic pain patients. We examined whether the combination of opioids (tramadol and morphine) with indomethacin or acetaminophen produce favorable effects on neuropathic pain and compared the efficacy for neuropathic pain with that for inflammatory pain. The carrageenan model was used as the inflammatory pain model while the tibial neuroma transposition (TNT) model was used as the neuropathic pain model. The tibial nerve is transected in the TNT model, with the tibial nerve stump then transpositioned to the lateral aspect of the hindlimb. Neuropathic pain (mechanical allodynia and neuroma pain) is observed after TNT injury. Drugs were administered orally. In the carrageenan model, all drugs produced anti-allodynic effects and all drug combinations, but not tramadol + indomethacin combination, produced synergistic anti-allodynic effects. In the TNT model, tramadol and morphine, but not acetaminophen and indomethacin, produced anti-neuropathic pain effects. In the combination, with the exception of morphine + acetaminophen combination, both acetaminophen and indomethacin reduced the 50% effective dose (ED50) of tramadol and morphine as compared with the ED50s for the single drug study in the TNT model. The ED50s of tramadol and morphine in the carrageenan combination test were not statistically significantly different from the ED50s in the TNT model combination study. The combination of opioids with indomethacin or acetaminophen produced a synergistic analgesic effect both in inflammatory and neuropathic pain with some exceptions. The efficacy of these combinations for neuropathic pain was not different from that for inflammatory pain.

Activities of the human immunodeficiency virus type 1 (HIV-1) protease inhibitor nelfinavir mesylate in combination with reverse transcriptase and protease inhibitors against acute HIV-1 infection in vitro.

PubMed

Patick, A K; Boritzki, T J; Bloom, L A

1997-10-01

Nelfinavir mesylate (formerly AG1343) is a potent and selective, nonpeptidic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease that was discovered by protein structure-based design methodologies. We evaluated the antiviral and cytotoxic effects of two-drug combinations of nelfinavir with the clinically approved antiretroviral therapeutics zidovudine (ZDV), lamivudine (3TC), dideoxycytidine (ddC; zalcitabine), stavudine (d4T), didanosine (ddI), indinavir, saquinavir, and ritonavir and a three-drug combination of nelfinavir with ZDV and 3TC against an acute HIV-1 strain RF infection of CEM-SS cells in vitro. Quantitative assessment of drug interaction was evaluated by a universal response surface approach (W. R. Greco, G. Bravo, and J. C. Parsons, Pharm. Rev. 47:331-385, 1995) and by the method of M. N. Prichard and C. Shipman (Antiviral Res. 14:181-206, 1990). Both analytical methods yielded similar results and showed that the two-drug combinations of nelfinavir with the reverse transcriptase inhibitors ZDV, 3TC, ddI, d4T, and ddC and the three-drug combination with ZDV and 3TC resulted in additive to statistically significant synergistic interactions. In a similar manner, the combination of nelfinavir with the three protease inhibitors resulted in additive (ritonavir and saquinavir) to slightly antagonistic (indinavir) interactions. In all combinations, minimal cellular cytotoxicity was observed with any drug alone and in combination. These results suggest that administration of combinations of the appropriate doses of nelfinavir with other currently approved antiretroviral therapeutic agents in vivo may result in enhanced antiviral activity with no associated increase in cellular cytotoxicity.

Activities of the human immunodeficiency virus type 1 (HIV-1) protease inhibitor nelfinavir mesylate in combination with reverse transcriptase and protease inhibitors against acute HIV-1 infection in vitro.

PubMed Central

Patick, A K; Boritzki, T J; Bloom, L A

1997-01-01

Nelfinavir mesylate (formerly AG1343) is a potent and selective, nonpeptidic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease that was discovered by protein structure-based design methodologies. We evaluated the antiviral and cytotoxic effects of two-drug combinations of nelfinavir with the clinically approved antiretroviral therapeutics zidovudine (ZDV), lamivudine (3TC), dideoxycytidine (ddC; zalcitabine), stavudine (d4T), didanosine (ddI), indinavir, saquinavir, and ritonavir and a three-drug combination of nelfinavir with ZDV and 3TC against an acute HIV-1 strain RF infection of CEM-SS cells in vitro. Quantitative assessment of drug interaction was evaluated by a universal response surface approach (W. R. Greco, G. Bravo, and J. C. Parsons, Pharm. Rev. 47:331-385, 1995) and by the method of M. N. Prichard and C. Shipman (Antiviral Res. 14:181-206, 1990). Both analytical methods yielded similar results and showed that the two-drug combinations of nelfinavir with the reverse transcriptase inhibitors ZDV, 3TC, ddI, d4T, and ddC and the three-drug combination with ZDV and 3TC resulted in additive to statistically significant synergistic interactions. In a similar manner, the combination of nelfinavir with the three protease inhibitors resulted in additive (ritonavir and saquinavir) to slightly antagonistic (indinavir) interactions. In all combinations, minimal cellular cytotoxicity was observed with any drug alone and in combination. These results suggest that administration of combinations of the appropriate doses of nelfinavir with other currently approved antiretroviral therapeutic agents in vivo may result in enhanced antiviral activity with no associated increase in cellular cytotoxicity. PMID:9333041

Assessment of knowledge, attitude, and practices on fixed dose combinations among postgraduate dental students.

PubMed

Vinnakota, Narayana R; Krishna, V; Viswanath, V; Ahmed, Zaheer; Shaik, Kamal S; Boppana, Naveen K

2016-12-01

To assess the knowledge, attitude, and practices of fixed dose combination drugs among postgraduate dental students. A cross-sectional study was carried out among postgraduate dental students of dental colleges in coastal Andhra Pradesh. Three colleges were randomly selected and students of all the three years were included. Data was collected from the specialities of oral medicine and radiology, oral surgery, endodontics, pedodontics, periodontics, and public health dentistry. The total sample was 90 postgraduate students; informed consent was obtained from the participants, and a pretested questionnaire was distributed to them. Data was analyzed using the Statistical Package for the Social Sciences version 20 software. Out of 90 postgraduates, 33 were males and 57 were females. Thirty-five percent were aware of the essential medical list (EML), among them 11% were from oral medicine and radiology and 6.7% were from pedodontics. However, most of them were unaware of the number of fixed dose combination drugs present in the World Health Organization EML. None of them were able to name at least a single banned fixed dose combination drug. Most of them were unaware of the advantages and disadvantages of using fixed dose combination drugs. Amoxicillin with clavulanic acid was the most common drug prescribed by students (73.3%) followed by ofloxacin with ornidazole (54.4%), ibuprofen with paracetamol (53.3%), and sulfamethoxazole with trimethoprim (6%). Most of them were unaware of the rationality in using fixed dose combination drugs. Common sources of information were medical representatives 43 (47.8%), internet 39 (43.3%), and 12 (13.3%) reported using WHO EML. There is an urgent need to improve knowledge on the rationality for using fixed dose combination, EML, and banned fixed dose combination in India to the promote rational use of fixed dose combination.

Modelling PK/QT relationships from Phase I dose-escalation trials for drug combinations and developing quantitative risk assessments of clinically relevant QT prolongations.

PubMed

Sinclair, Karen; Kinable, Els; Grosch, Kai; Wang, Jixian

2016-05-01

In current industry practice, it is difficult to assess QT effects at potential therapeutic doses based on Phase I dose-escalation trials in oncology due to data scarcity, particularly in combinations trials. In this paper, we propose to use dose-concentration and concentration-QT models jointly to model the exposures and effects of multiple drugs in combination. The fitted models then can be used to make early predictions for QT prolongation to aid choosing recommended dose combinations for further investigation. The models consider potential correlation between concentrations of test drugs and potential drug-drug interactions at PK and QT levels. In addition, this approach allows for the assessment of the probability of QT prolongation exceeding given thresholds of clinical significance. The performance of this approach was examined via simulation under practical scenarios for dose-escalation trials for a combination of two drugs. The simulation results show that invaluable information of QT effects at therapeutic dose combinations can be gained by the proposed approaches. Early detection of dose combinations with substantial QT prolongation is evaluated effectively through the CIs of the predicted peak QT prolongation at each dose combination. Furthermore, the probability of QT prolongation exceeding a certain threshold is also computed to support early detection of safety signals while accounting for uncertainty associated with data from Phase I studies. While the prediction of QT effects is sensitive to the dose escalation process, the sensitivity and limited sample size should be considered when providing support to the decision-making process for further developing certain dose combinations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

21 CFR 333.160 - Labeling of permitted combinations of active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... combination, as established in the statement of identity sections of the applicable OTC drug monographs. For a... sections of the applicable OTC drug monographs. (b) Indications. The labeling of the product states, under... the “Indications” sections of the applicable OTC drug monographs, unless otherwise stated in this...

The Global Fund to Fight AIDS, Tuberculosis, and Malaria: Progress Report and Issues for Congress

DTIC Science & Technology

2006-04-25

artemisinin -based combination drug treatments (ACT). Artemisinin -based treatments have been found to be effective in dealing with drug-resistant...and have no observable resistance are considerably more expensive. The new drugs called, “ artemisinin -based combination therapies” (ACTs) cost about

78 FR 21128 - Molecular Diagnostic Instruments With Combined Functions; Draft Guidance for Industry and Food...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-09

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-D-0258] Molecular Diagnostic Instruments With Combined Functions; Draft Guidance for Industry and Food and Drug Administration Staff; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food...

Laser-assisted delivery of synergistic combination chemotherapy in in vivo skin.

PubMed

Wenande, Emily; Tam, Joshua; Bhayana, Brijesh; Schlosser, Steven Kyle; Ishak, Emily; Farinelli, William A; Chlopik, Agata; Hoang, Mai P; Pinkhasov, Omar R; Caravan, Peter; Rox Anderson, R; Haedersdal, Merete

2018-04-10

The effectiveness of topical drugs for treatment of non-melanoma skin cancer is greatly reduced by insufficient penetration to deep skin layers. Ablative fractional lasers (AFLs) are known to enhance topical drug uptake by generating narrow microchannels through the skin, but information on AFL-drug delivery in in vivo conditions is limited. In this study, we examined pharmacokinetics, biodistribution and toxicity of two synergistic chemotherapy agents, cisplatin and 5-fluorouracil (5-FU), following AFL-assisted delivery alone or in combination in in vivo porcine skin. Detected at 0-120 h using mass spectrometry techniques, we demonstrated that fractional CO 2 laser pretreatment (196 microchannels/cm 2 , 852 μm ablation depth) leads to rapid drug uptake in 1500 μm deep skin layers, with a sixfold enhancement in peak cisplatin concentrations versus non-laser-treated controls (5 h, P = 0.005). Similarly, maximum 5-FU deposition was measured within an hour of AFL-delivery, and exceeded peak deposition in non-laser-exposed skin that had undergone topical drug exposure for 5 days. Overall, this accelerated and deeper cutaneous drug uptake resulted in significantly increased inflammatory and histopathological effects. Based on clinical scores and transepidermal water loss measurement, AFL intensified local toxic responses to drugs delivered alone and in combination, while systemic drug exposure remained undetectable. Quantitative histopathologic analyses correspondingly revealed significantly reduced epidermal proliferation and greater cellular apoptosis after AFL-drug delivery; particularly after combined cisplatin + 5-FU exposure. In sum, by overcoming the primary limitation of topical drug penetration and providing accelerated, enhanced and deeper delivery, AFL-assisted combination chemotherapy may represent a promising treatment strategy for non-melanoma skin cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of nicotine on ethanol-induced locomotor sensitization: A model of neuroadaptation.

PubMed

Gubner, Noah R; Phillips, Tamara J

2015-07-15

Co-morbid use of nicotine-containing tobacco products and alcohol (ethanol) is prevalent in young adults initiating use and in alcohol dependent adults, suggesting that these drugs in combination may increase risk to develop dependence on one or both drugs. Neuroadaptations caused by repeated drug exposure are related to the development of drug dependence and vulnerability to relapse. Locomotor sensitization has been used as a behavioral measure used to detect changes in neural drug sensitivity that are thought to contribute to drug dependence and relapse. Locomotor sensitization was measured in the current studies to examine potential differences in the effects of nicotine and ethanol given alone and in combination. Baseline activity levels of DBA/2J mice were assessed on 2 days, then mice were treated for 10 days with saline, nicotine (1 or 2mg/kg of nicotine tartrate), ethanol (1 or 2g/kg), or nicotine plus ethanol and locomotor activity was assessed every third day. On the following day, all mice were challenged with ethanol to measure the expression of sensitization. Mice treated with both nicotine and ethanol exhibited greater stimulation than predicted from the combined independent effects of these drugs, consistent with our previously published results. The combined effects of nicotine and ethanol on locomotor sensitization were dependent on the dose of ethanol and whether testing was performed after the drugs were given together, or after challenge with ethanol alone. These results suggest that nicotine and ethanol in combination can have neuroadaptive effects that differ from the independent effects of these drugs. Published by Elsevier B.V.

The novel combination of theophylline and bambuterol as a potential treatment of hypoxemia in humans.

PubMed

Strand, Trond-Eirik; Khiabani, Hasse Z; Boico, Alina; Radiloff, Daniel; Zhao, Yulin; Hamilton, Karyn L; Christians, Uwe; Klawitter, Jelena; Noveck, Robert J; Piantadosi, Claude A; Bell, Christopher; Irwin, David; Schroeder, Thies

2017-09-01

Hypoxemia can be life-threatening, both acutely and chronically. Because hypoxemia causes vascular dysregulation that further restricts oxygen availability to tissue, it can be pharmacologically addressed. We hypothesized that theophylline can be safely combined with the β2-adrenergic vasodilator bambuterol to improve oxygen availability in hypoxemic patients. Ergogenicity and hemodynamic effects of bambuterol and theophylline were measured in rats under hypobaric and normobaric hypoxia (12% O 2 ). Feasibility in humans was assessed using randomized, double-blind testing of the influence of combined slow-release theophylline (300 mg) and bambuterol (20 mg) on adverse events (AEs), plasma K + , pulse, blood pressure, and drug interaction. Both drugs and their combination significantly improved hypoxic endurance in rats. In humans, common AEs were low K + (<3.5 mmol/L; bambuterol: 12, theophylline: 4, combination: 13 episodes) and tremors (10, 0, 14 episodes). No exacerbation or serious AE occurred when drugs were combined. A drop in plasma K + coincided with peak bambuterol plasma concentrations. Bambuterol increased heart rate by approximately 13 bpm. Drug interaction was present but small. We report promise, feasibility, and relative safety of combined theophylline and bambuterol as a treatment of hypoxemia in humans. Cardiac safety and blood K + will be important safety endpoints when testing these drugs in hypoxemic subjects.

[Multiresistant Pseudomonas spp. in vitro susceptibility to a combination of two antibiotics].

PubMed

Pliego-Castañeda, Q F B Amanda; Yánez-Viguri, Jorge Antonio; López-Valle, Tiburcio

2005-01-01

In vitro antibiotic combination testing would guide therapy selection in patients severely affected by multi-drug resistant Pseudomonas. In vitro, a two-antibiotic combination susceptible against multi-drug resistant Pseudomonas isolated at the Laboratorio Clínico of the Hospital de Oncología, Centro Médico Nacional Siglo XXI in Mexico City were analyzed to determine which antibiotic combination showed the best bactericidal activity. During 10 months, 30 multi-drug resistant Pseudomonas strains were tested. An automated method was used, including a diluting solution with a well-known concentration of a second antibiotic. Quality controls recommended by the NCCLS were used. Pseudomonas aeruginosa ATCC 27853; Escherichia coli ATCC 25922; and Escherichia coli ATCC 35218. Combinations were betalactamics-aminoglycosides; carbapenemis-amikacin; fluoroquinolones-cefepime; and ciprofloxacin-ampicillin. Ampicillin-ciprofloxacin combination was bactericidal against 100% of the isolates. Cefazolin, cefixime and ticarcillin with amikacin: <50%; aztreonam, cefoxilin, cefuroxime, cefotaxime, ceftazidime and piperacillin with amikacin: 50-60%; cefepime with gentamicin: 76%; cefepime with amikacin: 86%; imipenem and meropenem with amikacin: 70% and 76%; cefepime with ciprofloxacin: 83%; cefepime with levofloxacin: 73%. In vitro antibiotic combination susceptibilities against multi-drug resistant bacteria would be the only way to guide clinicians to select the best therapy in severe infections. We found that the ampicillin-ciprofloxacin combination showed the best in vitro effect against multi-drug resistant Pseudomonas.

Nebivolol and valsartan as a fixed-dose combination for the treatment of hypertension.

PubMed

Sander, Gary E; Giles, Thomas D

2015-04-01

The fixed-dose combination of nebivolol and valsartan drug has been clinically evaluated and demonstrated to represent a unique combination of nebivolol, a selective β1-adrenoceptor antagonist and a β3-adrenoceptor agonist; β3 receptor activation increases endothelial nitric oxide and produces vasodilation. Valsartan is highly selective angiotensin AT1 receptor blocker and exerts its major pharmacological effect by decreasing angiotensin II-induced vasoconstriction and production of aldosterone. The addition of nebivolol counteracts the effects of increased angiotensin II concentrations resulting from potent AT1 blockade. This review describes a recently completed trial establishing the efficacy of the nebivolol/valsartan combination. This review provides a literature search of pertinent pharmacological and clinical data that describes the mechanisms of both drugs individually and the results of a clinical trial comparing fixed-dose combinations of nebivolol with valsartan as compared with each drug as monotherapy. Fixed-dose combination drugs are intended to improve patient compliance and reduce drug costs, as well as to reduce long-term cardiovascular event rates and block counter-regulatory effects due to monotherapy. The vast majority of hypertensive patients will require at least two medications. We believe that the clinical evidence suggests that the combination of nebivolol with valsartan offers a definite clinical benefit, combining β1-adrenoceptor and angiotensin AT1 receptor blockade with β3 receptor activation and resultant increase in nitric oxide and vasodilation.

Enhanced Transdermal Delivery by Combined Application of Dissolving Microneedle Patch on Serum-Treated Skin.

PubMed

Kim, Suyong; Dangol, Manita; Kang, Geonwoo; Lahiji, Shayan F; Yang, Huisuk; Jang, Mingyu; Ma, Yonghao; Li, Chengguo; Lee, Sang Gon; Kim, Chang Hyun; Choi, Young Wook; Kim, So Jeong; Ryu, Ja Hyun; Baek, Ji Hwoon; Koh, Jaesuk; Jung, Hyungil

2017-06-05

Dissolving microneedle (DMN), a transdermal drug delivery system in which drugs are encapsulated in a biodegradable polymeric microstructure, is designed to dissolve after skin penetration and release the encapsulated drugs into the body. However, because of limited loading capacity of drugs within microsized structures, only a small dosage can be delivered, which is often insufficient for patients. We propose a novel DMN application that combines topical and DMN application simultaneously to improve skin permeation efficiency. Drugs in pretreated topical formulation and encapsulated drugs in DMN patch are delivered into the skin through microchannels created by DMN application, thus greatly increasing the delivered dose. We used 4-n-butylresorcinol to treat human hyperpigmentation and found that sequential application of serum formulation and DMNs was successful. In skin distribution experiments using Alexa Fluor 488 and 568 dyes as model drugs, we confirmed that the pretreated serum formulation was delivered into the skin through microchannels created by the DMNs. In vitro skin permeation and retention experiments confirmed that this novel combined application delivered more 4-n-butylresorcinol into the skin than traditional DMN-only and serum-only applications. Moreover, this combined application showed a higher efficacy in reducing patients' melanin index and hyperpigmented regions compared with the serum-only application. As combined application of DMNs on serum-treated skin can overcome both dose limitations and safety concerns, this novel approach can advance developments in transdermal drug delivery.

Nanodrug formulations to enhance HIV drug exposure in lymphoid tissues and cells: clinical significance and potential impact on treatment and eradication of HIV/AIDS

PubMed Central

Shao, Jingwei; Kraft, John C; Li, Bowen; Yu, Jesse; Freeling, Jennifer; Koehn, Josefin; Ho, Rodney JY

2016-01-01

Although oral combination antiretroviral therapy effectively clears plasma HIV, patients on oral drugs exhibit much lower drug concentrations in lymph nodes than blood. This drug insufficiency is linked to residual HIV in cells of lymph nodes. While nanoformulations improve drug solubility, safety and delivery, most HIV nanoformulations are intended to extend plasma levels. A stable nanodrug combination that transports, delivers and accumulates in lymph nodes is needed to clear HIV in lymphoid tissues. This review discusses limitations of current oral combination antiretroviral therapy and advances in anti-HIV nanoformulations. A ‘systems approach’ has been proposed to overcome these limitations. This concept has been used to develop nanoformulations for overcoming drug insufficiency, extending cell and tissue exposure and clearing virus for treating HIV/AIDS. PMID:26892323

The compatibility and stability of midazolam and dexamethasone in infusion solutions.

PubMed

Good, Phillip D; Schneider, Jennifer J; Ravenscroft, Peter J

2004-05-01

The delivery of subcutaneous medication by continuous infusion is common in palliative medicine. Many centers combine multiple medications, but the analytical confirmation of the compatibility and stability of these combinations has rarely been performed. This study examined the compatibility and stability of midazolam and dexamethasone using high performance liquid chromatography. Nine different solutions were prepared in polypropylene syringes by combining these two drugs with 0.9% sodium chloride. When these two drugs were combined in a syringe, there was significant loss of midazolam over 48 hours, with only 60-80% of the initial concentration remaining in syringes stored at 35-39 degrees C. This study demonstrates that cloudiness of a solution is not the only predictor of drug loss and that drug loss may occur even in solutions that remain clear at time of preparation. The clinical implications of these results are that dexamethasone and midazolam should not be combined in syringe driver solutions.

Antibiotic-non-antibiotic combinations for combating extremely drug-resistant Gram-negative 'superbugs'.

PubMed

Schneider, Elena K; Reyes-Ortega, Felisa; Velkov, Tony; Li, Jian

2017-02-28

The emergence of antimicrobial resistance of Gram-negative pathogens has become a worldwide crisis. The status quo for combating resistance is to employ synergistic combinations of antibiotics. Faced with this fast-approaching post-antibiotic era, it is critical that we devise strategies to prolong and maximize the clinical efficacy of existing antibiotics. Unfortunately, reports of extremely drug-resistant (XDR) Gram-negative pathogens have become more common. Combining antibiotics such as polymyxin B or the broad-spectrum tetracycline and minocycline with various FDA-approved non-antibiotic drugs have emerged as a novel combination strategy against otherwise untreatable XDR pathogens. This review surveys the available literature on the potential benefits of employing antibiotic-non-antibiotic drug combination therapy. The apex of this review highlights the clinical utility of this novel therapeutic strategy for combating infections caused by 'superbugs'. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Computational identification of potential multi-drug combinations for reduction of microglial inflammation in Alzheimer disease

PubMed Central

Anastasio, Thomas J.

2015-01-01

Like other neurodegenerative diseases, Alzheimer Disease (AD) has a prominent inflammatory component mediated by brain microglia. Reducing microglial inflammation could potentially halt or at least slow the neurodegenerative process. A major challenge in the development of treatments targeting brain inflammation is the sheer complexity of the molecular mechanisms that determine whether microglia become inflammatory or take on a more neuroprotective phenotype. The process is highly multifactorial, raising the possibility that a multi-target/multi-drug strategy could be more effective than conventional monotherapy. This study takes a computational approach in finding combinations of approved drugs that are potentially more effective than single drugs in reducing microglial inflammation in AD. This novel approach exploits the distinct advantages of two different computer programming languages, one imperative and the other declarative. Existing programs written in both languages implement the same model of microglial behavior, and the input/output relationships of both programs agree with each other and with data on microglia over an extensive test battery. Here the imperative program is used efficiently to screen the model for the most efficacious combinations of 10 drugs, while the declarative program is used to analyze in detail the mechanisms of action of the most efficacious combinations. Of the 1024 possible drug combinations, the simulated screen identifies only 7 that are able to move simulated microglia at least 50% of the way from a neurotoxic to a neuroprotective phenotype. Subsequent analysis shows that of the 7 most efficacious combinations, 2 stand out as superior both in strength and reliability. The model offers many experimentally testable and therapeutically relevant predictions concerning effective drug combinations and their mechanisms of action. PMID:26097457

A versatile nanoplatform for synergistic combination therapy to treat human esophageal cancer.

PubMed

Wang, Xin-Shuai; Kong, De-Jiu; Lin, Tzu-Yin; Li, Xiao-Cen; Izumiya, Yoshihiro; Ding, Xue-Zhen; Zhang, Li; Hu, Xiao-Chen; Yang, Jun-Qiang; Gao, She-Gan; Lam, Kit S; Li, Yuan-Pei

2017-06-01

One of the major goals of precision oncology is to promote combination therapy to improve efficacy and reduce side effects of anti-cancer drugs based on their molecular mechanisms. In this study, we aimed to develop and validate new nanoformulations of docetaxel (DTX) and bortezomib (BTZ) for targeted combination therapy to treat human esophageal cancer. By leveraging our versatile disulfide cross-linked micelles (DCMs) platform, we developed nanoformulations of DTX and BTZ (named DTX-DCMs and BTZ-DCMs). Their physical properties were characterized; their anti-cancer efficacies and mechanisms of action were investigated in a human esophageal cancer cell line in vitro. Furthermore, the in vitro anti-tumor activities of combination therapies (concurrent drug treatment, sequential drug treatment, and treatment using different ratios of the drugs) were examined in comparison with the single drug treatment and free drug strategies. These drug-loaded nanoparticles were spherical in shape and relatively small in size of approximately 20-22 nm. The entrapment efficiencies of DTX and BTZ into nanoparticles were 82.4% and 84.1%, respectively. The drug release rates of DTX-DCMs and BTZ-DCMs were sustained, and greatly increased in the presence of GSH. These nanodrugs were effectively internalized by KYSE30 esophageal cancer cells, and dose-dependently induced cell apoptosis. We further revealed a strong synergistic effect between DTX-DCMs and BTZ-DCMs against KYSE30 esophageal cancer cells. Sequential combination therapy with DTX-DCMs followed by BTZ-DCMs exhibited the best anti-tumor efficacy in vitro. This study demonstrates that DTX and BTZ could be successfully nanoformulated into disulfide cross-linked micelles. The nanoformulations of DTX and BTZ demonstrate an immense potential for synergistic combination therapy to treat human esophageal cancer.

Anesthetic efficacy of ketamine–diazepam, ketamine–xylazine, and ketamine–acepromazine in Caspian Pond turtles (Mauremys caspica)

PubMed Central

Adel, Milad; Sadegh, Amin Bigham; Arizza, Vincenzo; Abbasi, Hossein; Inguglia, Luigi; Saravi, Hasan Nasrollahzadeh

2017-01-01

Objectives: The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles (Mauremys caspica). Subjects and Methods: Three groups of the Caspian Pond turtles (n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine–diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine–acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine–xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) were injected intramuscularly. The onset times of anesthetization and the recovery time were measured. Statistical analysis of the data was performed using one-way analysis of variance followed by t-tests, and P < 0.05 was considered statistically significant. Results: There were statistically significant differences in the mean of the onset times of anesthesia and recovery time among the three drug combinations depending on the treatment used. The onset of anesthesia of the animals treated with the ketamine–diazepam combination was 60% and 42% shorter, for male and female turtles, respectively, compared to that obtained with the ketamine–acepromazine combination and 64% (male turtles) and 50% (female turtles) shorter than that obtained with the ketamine–xylazine combination. Further, the recovery time, in male turtles, was 17% shorter in animals treated with the first drug combination than those treated with the ketamine–acepromazine combination and 37% shorter than those treated with the ketamine–xylazine combination. The recovery time, in female turtles, did not seem to be significantly different among treatments. Conclusions: The study showed that the ketamine–diazepam drug combination is the anesthetic combination with the fastest onset time and shortest recovery time. PMID:28458430

Modeling of signaling crosstalk-mediated drug resistance and its implications on drug combination.

PubMed

Sun, Xiaoqiang; Bao, Jiguang; You, Zhuhong; Chen, Xing; Cui, Jun

2016-09-27

The efficacy of pharmacological perturbation to the signaling transduction network depends on the network topology. However, whether and how signaling dynamics mediated by crosstalk contributes to the drug resistance are not fully understood and remain to be systematically explored. In this study, motivated by a realistic signaling network linked by crosstalk between EGF/EGFR/Ras/MEK/ERK pathway and HGF/HGFR/PI3K/AKT pathway, we develop kinetic models for several small networks with typical crosstalk modules to investigate the role of the architecture of crosstalk in inducing drug resistance. Our results demonstrate that crosstalk inhibition diminishes the response of signaling output to the external stimuli. Moreover, we show that signaling crosstalk affects the relative sensitivity of drugs, and some types of crosstalk modules that could yield resistance to the targeted drugs were identified. Furthermore, we quantitatively evaluate the relative efficacy and synergism of drug combinations. For the modules that are resistant to the targeted drug, we identify drug targets that can not only increase the relative drug efficacy but also act synergistically. In addition, we analyze the role of the strength of crosstalk in switching a module between drug-sensitive and drug-resistant. Our study provides mechanistic insights into the signaling crosstalk-mediated mechanisms of drug resistance and provides implications for the design of synergistic drug combinations to reduce drug resistance.

Interactions between imidazoline I2 receptor ligands and acetaminophen in adult male rats: antinociception and schedule-controlled responding

PubMed Central

Siemian, Justin N.; Li, Jiuzhou; Zhang, Yanan; Li, Jun-Xu

2015-01-01

Rationale Recent evidence suggests that imidazoline I2 receptor ligands are suitable for combination therapy with opioids. Quantitative analysis of I2 receptor ligands combined with non-opioid drugs is necessary for justification of alternative pain therapies. Objective This study systematically examined the anti-hyperalgesic and response rate-suppressing effects of selective I2 receptor ligands (2-BFI and phenyzoline) alone and in combination with acetaminophen. Methods Von Frey and Hargreaves tests were used to examine the anti-hyperalgesic effects of drugs in complete Freund’s adjuvant (CFA)-induced inflammatory pain in rats. Food-reinforced schedule-controlled responding was used to assess the rate-suppressing effects of study drugs. Dose-addition and isobolographic analyses were used to assess drug-drug interactions for all assays. Results 2-BFI (3.2–17.8 mg/kg, i.p.), phenyzoline (17.8–100 mg/kg, i.p.), and acetaminophen (56–178 mg/kg, i.p.) all dose-dependently produced significant antinociceptive effects. When studied as combinations, 2-BFI and acetaminophen produced infra-additive to additive interactions while phenyzoline and acetaminophen produced additive to supra-additive interactions. The same drug combinations suppressed response rate in a supra-additive manner. Conclusions Quantitative analysis of the anti-hyperalgesic and response rate-suppressing effects suggests that I2 receptor ligands are not well suited to combination therapy with acetaminophen. PMID:26613734

Smart Porous Silicon Nanoparticles with Polymeric Coatings for Sequential Combination Therapy.

PubMed

Xu, Wujun; Thapa, Rinez; Liu, Dongfei; Nissinen, Tuomo; Granroth, Sari; Närvänen, Ale; Suvanto, Mika; Santos, Hélder A; Lehto, Vesa-Pekka

2015-11-02

In spite of the advances in drug delivery, the preparation of smart nanocomposites capable of precisely controlled release of multiple drugs for sequential combination therapy is still challenging. Here, a novel drug delivery nanocomposite was prepared by coating porous silicon (PSi) nanoparticles with poly(beta-amino ester) (PAE) and Pluronic F-127, respectively. Two anticancer drugs, doxorubicin (DOX) and paclitaxel (PTX), were separately loaded into the core of PSi and the shell of F127. The nanocomposite displayed enhanced colloidal stability and good cytocompatibility. Moreover, a spatiotemporal drug release was achieved for sequential combination therapy by precisely controlling the release kinetics of the two tested drugs. The release of PTX and DOX occurred in a time-staggered manner; PTX was released much faster and earlier than DOX at pH 7.0. The grafted PAE on the external surface of PSi acted as a pH-responsive nanovalve for the site-specific release of DOX. In vitro cytotoxicity tests demonstrated that the DOX and PTX coloaded nanoparticles exhibited a better synergistic effect than the free drugs in inducing cellular apoptosis. Therefore, the present study demonstrates a promising strategy to enhance the efficiency of combination cancer therapies by precisely controlling the release kinetics of different drugs.

Azilsartan, aliskiren, and combination antihypertensives utilizing renin-angiotensin-aldosterone system antagonists.

PubMed

Lanier, Gregg; Sankholkar, Kedar; Aronow, Wilbert S

2014-01-01

Health care providers managing hypertension (HTN) have a large selection of pharmacologic agents to choose from, including several different classes of drugs and many similar drugs within each class. Antagonism of the renin-angiotensin-aldosterone system has been shown to be very effective for HTN, especially in patients with cardiovascular disease, diabetes, and heart failure. Within this group, there have been 2 new agents recently introduced to the US market and approved by the Food and Drug Administration. It is important for the HTN specialist to be familiar with the merits of these 2 drugs: the angiotensin receptor blocker Edarbi (azilsartan) and the renin inhibitor Tekturna (aliskiren). Additionally, there have been several new, fixed-dose combination antihypertensives introduced to the market since 2006 that use a renin-angiotensin-aldosterone antagonist. Seven of these combine 2 drugs together in a single pill: Edarbyclor (azilsartan/chlorthalidone), Exforge (amlodipine/valsartan), Azor (olmesartan/amlodipine), Twynsta (amlodipine/telmisartan), Tekturna HCT [aliskiren/hydrochlorothiazide (HCTZ)], Valturna (aliskiren/valsartan), Tekamlo (aliskiren/amlodipine). Three triple-drug combination medications have also been introduced recently: Exforge HCT (amlodipine/valsartan/HCTZ), Tribenzor (olmesartan/amlodipine/HCTZ), and Amturnide (aliskiren/amlodipine/hydrocholorothiazide). This review will summarize the trial data and important pharmacologic merits of these 2 new renin-angiotensin-aldosterone antagonists and the advantages of initiating treatment with one of the new fixed-dose, combination drugs approved over the last 5 years.

Synergistic Activation of Latent HIV-1 Expression by Novel Histone Deacetylase Inhibitors and Bryostatin-1.

PubMed

Martínez-Bonet, Marta; Clemente, Maria Isabel; Serramía, Maria Jesús; Muñoz, Eduardo; Moreno, Santiago; Muñoz-Fernández, Maria Ángeles

2015-11-13

Viral reactivation from latently infected cells has become a promising therapeutic approach to eradicate HIV. Due to the complexity of the viral latency, combinations of efficient and available drugs targeting different pathways of latency are needed. In this work, we evaluated the effect of various combinations of bryostatin-1 (BRY) and novel histone deacetylase inhibitors (HDACIs) on HIV-reactivation and on cellular phenotype. The lymphocyte (J89GFP) or monocyte/macrophage (THP89GFP) latently infected cell lines were treated with BRY, panobinostat (PNB) and romidepsin (RMD) either alone or in combination. Thus, the effect on the viral reactivation was evaluated. We calculated the combination index for each drug combination; the BRY/HDACIs showed a synergistic HIV-reactivation profile in the majority of the combinations tested, whereas non-synergistic effects were observed when PNB was mixed with RMD. Indeed, the 75% effective concentrations of BRY, PNB and RMD were reduced in these combinations. Moreover, primary CD4 T cells treated with such drug combinations presented similar activation and proliferation profiles in comparison with single drug treated cells. Summing up, combinations between BRY, PNB and/or RMD presented a synergistic profile by inducing virus expression in HIV-latently infected cells, rendering these combinations an attractive novel and safe option for future clinical trials.

Folate-modified, curcumin and paclitaxel co-loaded PLA-TPGS nanoparticles: preparation, optimization and in vitro cytotoxicity assays

NASA Astrophysics Data System (ADS)

Doan Do, Hai; Le Thi, Hao; Huong Le Thi, Thu; Nguyen, Hoai Nam; Khanh Bui, Van; Nhung Hoang Thi, My; Thu Ha, Phuong

2018-06-01

Development of chemoresistance is a significant restriction on the success of cancer treatment. Combination chemotherapy and drug delivery nanosystem are two promising strategies to overcome this limitation. Administration of two or more anticancer drugs at the same time can promote synergistic effect and suppress drug resistance through distinct mechanisms of action. Drug delivery nanosystem, on the other hand, improves delivery, efficacy and safety of drugs, and also can escape from some mechanisms of drug resistance. In this study we prepared drug delivery nanosystems from copolymers of lactic acid (PLA) and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). The nanosystems incorporated with folic acid as targeting agent were used to load curcumin (Cur) and paclitaxel (PTX) contemporaneously and denoted as (Cur  +  PTX)-PLA-TPGS-Fol. The results showed that (Cur  +  PTX)-PLA-TPGS-Fol nanoparticles has average size range of 100–200 nm depending on the ratio between PLA and TPGS. Loading efficacy of the two drugs was about 35%–83% with the highest encapsulation efficiency belonged to the system with the highest ratio of PLA. All of the prepared nanosystems with single drug or in combination exhibited strong cytotoxicity to cancer cells, but the combination was more effective in case of A549 cancer cell line. These results showed that our combination of Cur and PTX in our drug delivery nanosystem can be a promising candidate for cancer treatment.

21 CFR 310.3 - Definitions and interpretations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... proportion of a substance in a combination, even though such combination containing such substance in other proportion is not a new drug. (4) The newness of use of such drug in diagnosing, curing, mitigating, treating, or preventing a disease, or to affect a structure or function of the body, even though such drug is...

21 CFR 310.3 - Definitions and interpretations.

Code of Federal Regulations, 2013 CFR

2013-04-01

... proportion of a substance in a combination, even though such combination containing such substance in other proportion is not a new drug. (4) The newness of use of such drug in diagnosing, curing, mitigating, treating, or preventing a disease, or to affect a structure or function of the body, even though such drug is...

21 CFR 310.3 - Definitions and interpretations.

Code of Federal Regulations, 2012 CFR

2012-04-01

... proportion of a substance in a combination, even though such combination containing such substance in other proportion is not a new drug. (4) The newness of use of such drug in diagnosing, curing, mitigating, treating, or preventing a disease, or to affect a structure or function of the body, even though such drug is...

21 CFR 510.3 - Definitions and interpretations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... intended drug use of the proportion of a substance in a combination, even though such combination containing such substance in other proportion is not a new animal drug; (4) the newness for its intended drug..., mitigating, treating, or preventing a disease, or to affect a structure or function of the animal body, even...

78 FR 35940 - Guidance for Industry on Codevelopment of Two or More New Investigational Drugs for Use in...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-14

... underlie many complex diseases, such as cancer, cardiovascular disease, and infectious diseases. This...., ``new investigational drugs'') to be used in combination to treat a disease or condition. The guidance... (i.e., ``new investigational drugs'') to be used in combination to treat a disease or condition...

Modulation of interleukin-1 secretion by immunosuppressive drugs, alone and in combination.

PubMed

Reisman, L; Lin, W G; Martinelli, G P

1995-03-01

This study evaluates the ability of the immunosuppressive drugs dexamethasone, cyclosporine, FK506 and rapamycin, alone and in combination to suppress interleukin-1 beta (IL-1 beta) secretion in vitro by THP-1 cells when stimulated by lipopolysaccharide. All four drugs, when added to cell culture medium at therapeutic concentrations, significantly decrease secretion of the monokine to well below control levels. However, only dexamethasone completely suppresses IL-1 beta secretion in a dose-dependent fashion. Cyclosporine, FK506 and rapamycin only partially suppress secretion of IL-1 beta at concentrations within their therapeutic ranges and increasing concentrations of the drugs do not result in further suppression of secretion. Likewise, the combination of any two of these three drugs does not provide any additional suppressive effect. Dexamethasone, however, when added in increasing concentrations in combination with any of the other drugs, results in further suppression of IL-1 secretion in a dose-dependent fashion. These data suggest that cyclosporine, FK506 and rapamycin all share a common effect on the production of IL-1 beta, different from that of dexamethasone.

Modeling the effects of space structure and combination therapies on phenotypic heterogeneity and drug resistance in solid tumors.

PubMed

Lorz, Alexander; Lorenzi, Tommaso; Clairambault, Jean; Escargueil, Alexandre; Perthame, Benoît

2015-01-01

Histopathological evidence supports the idea that the emergence of phenotypic heterogeneity and resistance to cytotoxic drugs can be considered as a process of selection in tumor cell populations. In this framework, can we explain intra-tumor heterogeneity in terms of selection driven by the local cell environment? Can we overcome the emergence of resistance and favor the eradication of cancer cells by using combination therapies? Bearing these questions in mind, we develop a model describing cell dynamics inside a tumor spheroid under the effects of cytotoxic and cytostatic drugs. Cancer cells are assumed to be structured as a population by two real variables standing for space position and the expression level of a phenotype of resistance to cytotoxic drugs. The model takes explicitly into account the dynamics of resources and anticancer drugs as well as their interactions with the cell population under treatment. We analyze the effects of space structure and combination therapies on phenotypic heterogeneity and chemotherapeutic resistance. Furthermore, we study the efficacy of combined therapy protocols based on constant infusion and bang-bang delivery of cytotoxic and cytostatic drugs.

Sample size requirements for separating out the effects of combination treatments: randomised controlled trials of combination therapy vs. standard treatment compared to factorial designs for patients with tuberculous meningitis.

PubMed

Wolbers, Marcel; Heemskerk, Dorothee; Chau, Tran Thi Hong; Yen, Nguyen Thi Bich; Caws, Maxine; Farrar, Jeremy; Day, Jeremy

2011-02-02

In certain diseases clinical experts may judge that the intervention with the best prospects is the addition of two treatments to the standard of care. This can either be tested with a simple randomized trial of combination versus standard treatment or with a 2 x 2 factorial design. We compared the two approaches using the design of a new trial in tuberculous meningitis as an example. In that trial the combination of 2 drugs added to standard treatment is assumed to reduce the hazard of death by 30% and the sample size of the combination trial to achieve 80% power is 750 patients. We calculated the power of corresponding factorial designs with one- to sixteen-fold the sample size of the combination trial depending on the contribution of each individual drug to the combination treatment effect and the strength of an interaction between the two. In the absence of an interaction, an eight-fold increase in sample size for the factorial design as compared to the combination trial is required to get 80% power to jointly detect effects of both drugs if the contribution of the less potent treatment to the total effect is at least 35%. An eight-fold sample size increase also provides a power of 76% to detect a qualitative interaction at the one-sided 10% significance level if the individual effects of both drugs are equal. Factorial designs with a lower sample size have a high chance to be underpowered, to show significance of only one drug even if both are equally effective, and to miss important interactions. Pragmatic combination trials of multiple interventions versus standard therapy are valuable in diseases with a limited patient pool if all interventions test the same treatment concept, it is considered likely that either both or none of the individual interventions are effective, and only moderate drug interactions are suspected. An adequately powered 2 x 2 factorial design to detect effects of individual drugs would require at least 8-fold the sample size of the combination trial. Current Controlled Trials ISRCTN61649292.

Combination Approaches to Combat Multi-Drug Resistant Bacteria

PubMed Central

Worthington, Roberta J.; Melander, Christian

2013-01-01

The increasing prevalence of infections caused by multi-drug resistant bacteria is a global health problem that is exacerbated by the dearth of novel classes of antibiotics entering the clinic over the past 40 years. Herein we describe recent developments toward combination therapies for the treatment of multi-drug resistant bacterial infections. These efforts include antibiotic-antibiotic combinations, and the development of adjuvants that either directly target resistance mechanisms such as the inhibition of β-lactamase enzymes, or indirectly target resistance by interfering with bacterial signaling pathways such as two-component systems. We also discuss screening of libraries of previously approved drugs to identify non-obvious antimicrobial adjuvants. PMID:23333434

AIDS therapy with two, three or four agent combinations, applied in short sequences, differing from each other by drug rotation. I. First of two parts: a phase I trial equivalent, concerning five virostatics: AZT, ddI, ddC, acriflavine and an ellipticine analogue.

PubMed

Mathé, G; Pontiggia, P; Orbach-Arbouys, S; Triana, K; Ambetima, N; Morette, C; Hallard, M; Blanquet, D

1996-01-01

We have individually treated ten AIDS patients whose CD4 numbers were inferior to 200/mm3, with the five following HIV1 virostatics: a) azido-deoxythymidine (AZT), dideoxyinosine (ddI) and dideoxycytidine (ddC), which affect the same viral target, retrotranscriptase, b) acriflavine (ACF) and methyl-hydroxy-ellipticine (MHE) which we have discovered to be strong virostatics in vivo, in mice, against Friend's virus, and in man, against AZT resistant HIV1. We have shown that their combinations with AZT, hitting three viral targets, reduces in mice, the blood Friend's virus load below detectable level. Due to the short doubling time of HIV1, AIDS therapy must be continuous, and to allow the best tolerance, the five virostatic combinations were applied in short, three-week sequences, each differing as much as possible from the former and from the following one, due to drug rotation [1]. Among the ten patients, a) three received the two-drug combinations for 15 to 30 months, followed by the three-drug combinations, b) three received the three-drug combinations from the beginning, c) four received the four-drug combinations also from the beginning, two having less than 10 CD4/mm3 at initiation of treatment, and two having more than 100. The tolerance was remarkable: the only side-effect being macrocytosis. The application of the two-drug combination sequences maintained stable CD4 levels in two subjects whose viral load (the evaluation of which had became available) was, at the end of this period, of 4,486 and 39,238 RNA copies. The third subject who had received, an intensive UV irradiation for a psoriasis, presented an irreversible decrease in his CD4 count and a high viral load (1,352,495 RNA copies/mL) at the end of the two-drug period. Fifteen to 25 months after the shift to the three-drug combinations, the viral load decreased, from 39,328 to 13,291 in one of the non-UV irradiated subjects, and from 1,352,495 to 314,387 in the irradiated one. No subject had an increase in CD4 number. In the three patients having initially received the three-drug combinations, a very strong decrease of viral load was registered after periods of observation varying from 77 to 40 months, while the CD4 counts increased moderately in two subjects, and noticeably in the third (from 126 to 266). Out of the four subjects initially treated with four-drug combinations, the two with less than 10 CD4/mm3 had a moderate decrease in viral load in about three months, and the CD4 increased from 9 to 34/mm3 in one. But the two subjects, because of opportunistic infections and psychological reasons, abandoned their treatments. In the two subjects who had more than 100 CD4/mm2 at initiation of the four-drug combination treatment, the viral load decreased to undetectable levels after four months: but their CD4 counts, after some oscillations, had very moderately increased at the end of the observation period (respectively, from 200 to 222, and from 129 to 134). In practice, these results suggest the interest of conducting phase II or III studies of AIDS treatment protocols, starting with the four-drug combination model, and attempting to maintain the effect with the three-drug combination one. As for theoretical considerations, one must underline the contrast between the remarkable reduction of the viral load and the usually moderate increase of the CD4 counts. The study but not the trial has been interrupted, due to the unavailability of three antiproteases, saquinavir, ritonavir and indinavir, which are now introduced in the same type of combinations, one by one, in replacement of one of the studied agents as shown in figure 1. The effect of increasing the total number of virostatics from five to eight will be published in the second part of this article series.

A systematic review of combined student- and parent-based programs to prevent alcohol and other drug use among adolescents.

PubMed

Newton, Nicola C; Champion, Katrina E; Slade, Tim; Chapman, Cath; Stapinski, Lexine; Koning, Ina; Tonks, Zoe; Teesson, Maree

2017-05-01

Alcohol and other drug use among adolescents is a serious concern, and effective prevention is critical. Research indicates that expanding school-based prevention programs to include parenting components could increase prevention outcomes. This paper aims to identify and describe existing combined student- and parent-based programs for the prevention of alcohol and other drug use to evaluate the efficacy of existing programs. The PsycINFO, Medline, Central Register of Controlled trials and Cochrane databases were searched in April 2015 and additional articles were obtained from reference lists. Studies were included if they evaluated a combined universal intervention for students (aged 11-18 years old) and their parents designed to prevent alcohol and/or other drug use, and were delivered in a school-based setting. Risk of bias was assessed by two independent reviewers. Because of the heterogeneity of the included studies, it was not possible to conduct a meta-analysis and a qualitative description of the studies was provided. From a total of 1654 screened papers, 22 research papers met inclusion criteria, which included 13 trials of 10 programs. Of these, nine programs demonstrated significant intervention effects in terms of delaying or reducing adolescent alcohol and/or other drug use in at least one trial. This is the first review of combined student- and parent-based interventions to prevent and reduce alcohol and other drug use. Whilst existing combined student- and parent-based programs have shown promising results, key gaps in the literature have been identified and are discussed in the context of the development of future prevention programs. [Newton NC, Champion KE, Slade T, Chapman C, Stapinski L, Koning I, Tonks Z, Teesson M. A systematic review of combined student- and parent-based programs to prevent alcohol and other drug use among adolescents. Drug Alcohol Rev 2017;36:337-351]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

21 CFR 331.15 - Combination with nonantacid active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Combination with nonantacid active ingredients... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Active Ingredients § 331.15 Combination with nonantacid active ingredients. (a) An antacid may contain any generally...

21 CFR 332.15 - Combination with non-antiflatulent active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Combination with non-antiflatulent active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTIFLATULENT PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 332.15 Combination with non-antiflatulent active ingredients. An antiflatulent may contain any...

21 CFR 331.15 - Combination with nonantacid active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Combination with nonantacid active ingredients... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Active Ingredients § 331.15 Combination with nonantacid active ingredients. (a) An antacid may contain any generally...

21 CFR 332.15 - Combination with non-antiflatulent active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Combination with non-antiflatulent active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTIFLATULENT PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 332.15 Combination with non-antiflatulent active ingredients. An antiflatulent may contain any...

21 CFR 332.15 - Combination with non-antiflatulent active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Combination with non-antiflatulent active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTIFLATULENT PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 332.15 Combination with non-antiflatulent active ingredients. An antiflatulent may contain any...

21 CFR 331.15 - Combination with nonantacid active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Combination with nonantacid active ingredients... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Active Ingredients § 331.15 Combination with nonantacid active ingredients. (a) An antacid may contain any generally...

21 CFR 332.15 - Combination with non-antiflatulent active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Combination with non-antiflatulent active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTIFLATULENT PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 332.15 Combination with non-antiflatulent active ingredients. An antiflatulent may contain any...

21 CFR 331.15 - Combination with nonantacid active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Combination with nonantacid active ingredients... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Active Ingredients § 331.15 Combination with nonantacid active ingredients. (a) An antacid may contain any generally...

21 CFR 332.15 - Combination with non-antiflatulent active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Combination with non-antiflatulent active... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTIFLATULENT PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 332.15 Combination with non-antiflatulent active ingredients. An antiflatulent may contain any...

21 CFR 331.15 - Combination with nonantacid active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Combination with nonantacid active ingredients... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Active Ingredients § 331.15 Combination with nonantacid active ingredients. (a) An antacid may contain any generally...

Experiment on the factors for enhancing the susceptibility of cancer cells to chemotherapeutic drug by ultrasound microbubbles.

PubMed

Zhao, Ying-Zheng; Gao, Hui-Sheng; Zhou, Zhi-Cai; Tang, Qin-Qin; Lu, Cui-Tao; Jin, Zhuo; Tian, Ji-Lai; Xu, Yan-Yan; Tian, Xin-Qiao; Wang, Lee; Kong, Fan-Lei; Li, Xiao-Kun; Huang, Pin-Tong; He, Hui-Liao; Wu, Yan

2010-07-01

The objective of this study was to investigate the factors for enhancing the susceptibility of cancer cells to chemotherapeutic drug by ultrasound microbubbles. Ultrasound (US) combined with phospholipid-based microbubbles (MB) was used to enhance the susceptibility of colon cancer cell line SWD-620 to anticancer drugs Topotecan hydrochloride (TOP). Experiments were designed to investigate the influence of main factors on cell viability and cell inhibition, such as US intensity, MB concentration, drug combination with MB, asynchronous action between US triggered cavitation and drug entering cell, MB particle size. US exposure for 10 sec with US probe power at 0.6 W/cm(2) had satisfied cell viability. Treated with US combined with 15% MB, cell viability maintained more than 85% and cell inhibition 86.16%. Under optimal US combined with MB, TOP showed much higher cell inhibition than that of only TOP group. Cell inhibition under short delayed time (<2 h) for TOP addition did not show obvious difference. In terms of MB particle size, the order of cell inhibition was: Mixture > Micron bubble part > Nanometer bubble part. US combined with MB can enhance the susceptibility of cancer cells to chemotherapeutic drug, which may provide a potential method for US-mediated tumor chemotherapy.

Unprecedented Therapeutic Potential with a Combination of A2A/NR2B Receptor Antagonists as Observed in the 6-OHDA Lesioned Rat Model of Parkinson's Disease

PubMed Central

Michel, Anne; Downey, Patrick; Nicolas, Jean-Marie; Scheller, Dieter

2014-01-01

In Parkinson's disease, the long-term use of dopamine replacing agents is associated with the development of motor complications; therefore, there is a need for non-dopaminergic drugs. This study evaluated the potential therapeutic impact of six different NR2B and A2A receptor antagonists given either alone or in combination in unilateral 6-OHDA-lesioned rats without (monotherapy) or with (add-on therapy) the co-administration of L-Dopa: Sch-58261+ Merck 22; Sch-58261+Co-101244; Preladenant + Merck 22; Preladenant + Radiprodil; Tozadenant + Radiprodil; Istradefylline + Co-101244. Animals given monotherapy were assessed on distance traveled and rearing, whereas those given add-on therapy were assessed on contralateral rotations. Three-way mixed ANOVA were conducted to assess the main effect of each drug separately and to determine whether any interaction between two drugs was additive or synergistic. Additional post hoc analyses were conducted to compare the effect of the combination with the effect of the drugs alone. Motor activity improved significantly and was sustained for longer when the drugs were given in combination than when administered separately at the same dose. Similarly, when tested as add-on treatment to L-Dopa, the combinations resulted in higher levels of contralateral rotation in comparison to the single drugs. Of special interest, the activity observed with some combinations could not be described by a simplistic additive effect and involved more subtle synergistic pharmacological interactions. The combined administration of A2A/NR2B-receptor antagonists improved motor behaviour in 6-OHDA rats. Given the proven translatability of this model such a combination may be expected to be effective in improving motor symptoms in patients. PMID:25513815

Cooperative Targets of Combined mTOR/HDAC Inhibition Promote MYC Degradation.

PubMed

Simmons, John K; Michalowski, Aleksandra M; Gamache, Benjamin J; DuBois, Wendy; Patel, Jyoti; Zhang, Ke; Gary, Joy; Zhang, Shuling; Gaikwad, Snehal; Connors, Daniel; Watson, Nicholas; Leon, Elena; Chen, Jin-Qiu; Kuehl, W Michael; Lee, Maxwell P; Zingone, Adriana; Landgren, Ola; Ordentlich, Peter; Huang, Jing; Mock, Beverly A

2017-09-01

Cancer treatments often require combinations of molecularly targeted agents to be effective. mTORi (rapamycin) and HDACi (MS-275/entinostat) inhibitors have been shown to be effective in limiting tumor growth, and here we define part of the cooperative action of this drug combination. More than 60 human cancer cell lines responded synergistically (CI<1) when treated with this drug combination compared with single agents. In addition, a breast cancer patient-derived xenograft, and a BCL-XL plasmacytoma mouse model both showed enhanced responses to the combination compared with single agents. Mice bearing plasma cell tumors lived an average of 70 days longer on combination treatment compared with single agents. A set of 37 genes cooperatively affected (34 downregulated; 3 upregulated) by the combination responded pharmacodynamically in human myeloma cell lines, xenografts, and a P493 model, and were both enriched in tumors, and correlated with prognostic markers in myeloma patient datasets. Genes downregulated by the combination were overexpressed in several untreated cancers (breast, lung, colon, sarcoma, head and neck, myeloma) compared with normal tissues. The MYC/E2F axis, identified by upstream regulator analyses and validated by immunoblots, was significantly inhibited by the drug combination in several myeloma cell lines. Furthermore, 88% of the 34 genes downregulated have MYC-binding sites in their promoters, and the drug combination cooperatively reduced MYC half-life by 55% and increased degradation. Cells with MYC mutations were refractory to the combination. Thus, integrative approaches to understand drug synergy identified a clinically actionable strategy to inhibit MYC/E2F activity and tumor cell growth in vivo Mol Cancer Ther; 16(9); 2008-21. ©2017 AACR . ©2017 American Association for Cancer Research.

Genetic and Genomic Architecture of the Evolution of Resistance to Antifungal Drug Combinations

PubMed Central

Hill, Jessica A.; Ammar, Ron; Torti, Dax; Nislow, Corey; Cowen, Leah E.

2013-01-01

The evolution of drug resistance in fungal pathogens compromises the efficacy of the limited number of antifungal drugs. Drug combinations have emerged as a powerful strategy to enhance antifungal efficacy and abrogate drug resistance, but the impact on the evolution of drug resistance remains largely unexplored. Targeting the molecular chaperone Hsp90 or its downstream effector, the protein phosphatase calcineurin, abrogates resistance to the most widely deployed antifungals, the azoles, which inhibit ergosterol biosynthesis. Here, we evolved experimental populations of the model yeast Saccharomyces cerevisiae and the leading human fungal pathogen Candida albicans with azole and an inhibitor of Hsp90, geldanamycin, or calcineurin, FK506. To recapitulate a clinical context where Hsp90 or calcineurin inhibitors could be utilized in combination with azoles to render resistant pathogens responsive to treatment, the evolution experiment was initiated with strains that are resistant to azoles in a manner that depends on Hsp90 and calcineurin. Of the 290 lineages initiated, most went extinct, yet 14 evolved resistance to the drug combination. Drug target mutations that conferred resistance to geldanamycin or FK506 were identified and validated in five evolved lineages. Whole-genome sequencing identified mutations in a gene encoding a transcriptional activator of drug efflux pumps, PDR1, and a gene encoding a transcriptional repressor of ergosterol biosynthesis genes, MOT3, that transformed azole resistance of two lineages from dependent on calcineurin to independent of this regulator. Resistance also arose by mutation that truncated the catalytic subunit of calcineurin, and by mutation in LCB1, encoding a sphingolipid biosynthetic enzyme. Genome analysis revealed extensive aneuploidy in four of the C. albicans lineages. Thus, we identify molecular determinants of the transition of azole resistance from calcineurin dependence to independence and establish multiple mechanisms by which resistance to drug combinations evolves, providing a foundation for predicting and preventing the evolution of drug resistance. PMID:23593013

Combining Drugs to Treat Ovarian Cancer - Annual Plan

Cancer.gov

Approximately 70 percent of women diagnosed with ovarian cancer will die from the disease. Read about the NCI-funded combination drug trial that has successfully treated Betsy Brauser's recurrent cancer.

Motivations and values associated with combining sex and illicit drugs ('chemsex') among gay men in South London: findings from a qualitative study.

PubMed

Weatherburn, P; Hickson, F; Reid, D; Torres-Rueda, S; Bourne, A

2017-05-01

There is considerable public health concern about the combining of sex and illicit drugs (chemsex) among gay men. With a view to inform supportive therapeutic and clinical interventions, we sought to examine the motivations for engaging in chemsex among gay men living in South London. Community advertising recruited 30 gay men for qualitative semi-structured interview. Aged between 21 and 53 years, all lived in South London in the boroughs of Lambeth, Southwark and Lewisham and all had combined crystal methamphetamine, mephedrone and/or γ-hydroxybutyric acid/γ-butyrolactone with sex in the past 12 months. Transcripts were subjected to a thematic analysis. We broadly distinguished two groups of reasons for combining sex and drugs, within which we described eight distinct motivations. The first major group of motivations for combining drugs with sex was that drugs provide the means by which men can have the sex they desire by increasing libido, confidence, disinhibition and stamina. The second major group of motivations for chemsex was that drugs enhance the qualities of the sex that men value. Drugs made other men seem more attractive, increased physical sensations, intensified perceptions of intimacy and facilitated a sense of sexual adventure. Analysis revealed that sexualised drug use provides both motivation and capability to engage in the kinds of sex that some gay men value: sex that explores and celebrates adventurism. Those services providing (talking) interventions to men engaging in chemsex should consider these benefits of sexualised drug use alongside the harms arising. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Quantifying the effects of antiangiogenic and chemotherapy drug combinations on drug delivery and treatment efficacy

PubMed Central

Yιlmaz, Defne; Phipps, Colin; Kohandel, Mohammad

2017-01-01

Tumor-induced angiogenesis leads to the development of leaky tumor vessels devoid of structural and morphological integrity. Due to angiogenesis, elevated interstitial fluid pressure (IFP) and low blood perfusion emerge as common properties of the tumor microenvironment that act as barriers for drug delivery. In order to overcome these barriers, normalization of vasculature is considered to be a viable option. However, insight is needed into the phenomenon of normalization and in which conditions it can realize its promise. In order to explore the effect of microenvironmental conditions and drug scheduling on normalization benefit, we build a mathematical model that incorporates tumor growth, angiogenesis and IFP. We administer various theoretical combinations of antiangiogenic agents and cytotoxic nanoparticles through heterogeneous vasculature that displays a similar morphology to tumor vasculature. We observe differences in drug extravasation that depend on the scheduling of combined therapy; for concurrent therapy, total drug extravasation is increased but in adjuvant therapy, drugs can penetrate into deeper regions of tumor. PMID:28922358

Isobolographic analysis of the mechanisms of action of anticonvulsants from a combination effect.

PubMed

Matsumura, Nobuko; Nakaki, Toshio

2014-10-15

The nature of the pharmacodynamic interactions of drugs is influenced by the drugs׳ mechanisms of action. It has been hypothesized that drugs with different mechanisms are likely to interact synergistically, whereas those with similar mechanisms seem to produce additive interactions. In this review, we describe an extensive investigation of the published literature on drug combinations of anticonvulsants, the nature of the interaction of which has been evaluated by type I and II isobolographic analyses and the subthreshold method. The molecular targets of antiepileptic drugs (AEDs) include Na(+) and Ca(2+) channels, GABA type-A receptor, and glutamate receptors such as NMDA and AMPA/kainate receptors. The results of this review indicate that the nature of interactions evaluated by type I isobolographic analyses but not by the two other methods seems to be consistent with the above hypothesis. Type I isobolographic analyses may be used not only for evaluating drug combinations but also for predicting the targets of new drugs. Copyright © 2014 Elsevier B.V. All rights reserved.

Quantifying the effects of antiangiogenic and chemotherapy drug combinations on drug delivery and treatment efficacy.

PubMed

Yonucu, Sirin; Yιlmaz, Defne; Phipps, Colin; Unlu, Mehmet Burcin; Kohandel, Mohammad

2017-09-01

Tumor-induced angiogenesis leads to the development of leaky tumor vessels devoid of structural and morphological integrity. Due to angiogenesis, elevated interstitial fluid pressure (IFP) and low blood perfusion emerge as common properties of the tumor microenvironment that act as barriers for drug delivery. In order to overcome these barriers, normalization of vasculature is considered to be a viable option. However, insight is needed into the phenomenon of normalization and in which conditions it can realize its promise. In order to explore the effect of microenvironmental conditions and drug scheduling on normalization benefit, we build a mathematical model that incorporates tumor growth, angiogenesis and IFP. We administer various theoretical combinations of antiangiogenic agents and cytotoxic nanoparticles through heterogeneous vasculature that displays a similar morphology to tumor vasculature. We observe differences in drug extravasation that depend on the scheduling of combined therapy; for concurrent therapy, total drug extravasation is increased but in adjuvant therapy, drugs can penetrate into deeper regions of tumor.

Large-scale combining signals from both biomedical literature and the FDA Adverse Event Reporting System (FAERS) to improve post-marketing drug safety signal detection

PubMed Central

2014-01-01

Background Independent data sources can be used to augment post-marketing drug safety signal detection. The vast amount of publicly available biomedical literature contains rich side effect information for drugs at all clinical stages. In this study, we present a large-scale signal boosting approach that combines over 4 million records in the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and over 21 million biomedical articles. Results The datasets are comprised of 4,285,097 records from FAERS and 21,354,075 MEDLINE articles. We first extracted all drug-side effect (SE) pairs from FAERS. Our study implemented a total of seven signal ranking algorithms. We then compared these different ranking algorithms before and after they were boosted with signals from MEDLINE sentences or abstracts. Finally, we manually curated all drug-cardiovascular (CV) pairs that appeared in both data sources and investigated whether our approach can detect many true signals that have not been included in FDA drug labels. We extracted a total of 2,787,797 drug-SE pairs from FAERS with a low initial precision of 0.025. The ranking algorithm combined signals from both FAERS and MEDLINE, significantly improving the precision from 0.025 to 0.371 for top-ranked pairs, representing a 13.8 fold elevation in precision. We showed by manual curation that drug-SE pairs that appeared in both data sources were highly enriched with true signals, many of which have not yet been included in FDA drug labels. Conclusions We have developed an efficient and effective drug safety signal ranking and strengthening approach We demonstrate that large-scale combining information from FAERS and biomedical literature can significantly contribute to drug safety surveillance. PMID:24428898

Large-scale combining signals from both biomedical literature and the FDA Adverse Event Reporting System (FAERS) to improve post-marketing drug safety signal detection.

PubMed

Xu, Rong; Wang, QuanQiu

2014-01-15

Independent data sources can be used to augment post-marketing drug safety signal detection. The vast amount of publicly available biomedical literature contains rich side effect information for drugs at all clinical stages. In this study, we present a large-scale signal boosting approach that combines over 4 million records in the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and over 21 million biomedical articles. The datasets are comprised of 4,285,097 records from FAERS and 21,354,075 MEDLINE articles. We first extracted all drug-side effect (SE) pairs from FAERS. Our study implemented a total of seven signal ranking algorithms. We then compared these different ranking algorithms before and after they were boosted with signals from MEDLINE sentences or abstracts. Finally, we manually curated all drug-cardiovascular (CV) pairs that appeared in both data sources and investigated whether our approach can detect many true signals that have not been included in FDA drug labels. We extracted a total of 2,787,797 drug-SE pairs from FAERS with a low initial precision of 0.025. The ranking algorithm combined signals from both FAERS and MEDLINE, significantly improving the precision from 0.025 to 0.371 for top-ranked pairs, representing a 13.8 fold elevation in precision. We showed by manual curation that drug-SE pairs that appeared in both data sources were highly enriched with true signals, many of which have not yet been included in FDA drug labels. We have developed an efficient and effective drug safety signal ranking and strengthening approach We demonstrate that large-scale combining information from FAERS and biomedical literature can significantly contribute to drug safety surveillance.

Modeling Tumor Clonal Evolution for Drug Combinations Design.

PubMed

Zhao, Boyang; Hemann, Michael T; Lauffenburger, Douglas A

2016-03-01

Cancer is a clonal evolutionary process. This presents challenges for effective therapeutic intervention, given the constant selective pressure towards drug resistance. Mathematical modeling from population genetics, evolutionary dynamics, and engineering perspectives are being increasingly employed to study tumor progression, intratumoral heterogeneity, drug resistance, and rational drug scheduling and combinations design. In this review, we discuss promising opportunities these inter-disciplinary approaches hold for advances in cancer biology and treatment. We propose that quantitative modeling perspectives can complement emerging experimental technologies to facilitate enhanced understanding of disease progression and improved capabilities for therapeutic drug regimen designs.

Lessons from innovation in drug-device combination products.

PubMed

Couto, Daniela S; Perez-Breva, Luis; Saraiva, Pedro; Cooney, Charles L

2012-01-01

Drug-device combination products introduced a new dynamic on medical product development, regulatory approval, and corporate interaction that provide valuable lessons for the development of new generations of combination products. This paper examines the case studies of drug-eluting stents and transdermal patches to facilitate a detailed understanding of the challenges and opportunities introduced by combination products when compared to previous generations of traditional medical or drug delivery devices. Our analysis indicates that the largest barrier to introduce a new kind of combination products is the determination of the regulatory center that is to oversee its approval. The first product of a new class of combination products offers a learning opportunity for the regulator and the sponsor. Once that first product is approved, the leading regulatory center is determined, and the uncertainty about the entire class of combination products is drastically reduced. The sponsor pioneering a new class of combination products assumes a central role in reducing this uncertainty by advising the decision on the primary function of the combination product. Our analysis also suggests that this decision influences the nature (pharmaceutical, biotechnology, or medical devices) of the companies that will lead the introduction of these products into the market, and guide the structure of corporate interaction thereon. Copyright © 2011 Elsevier B.V. All rights reserved.

Ruxolitinib synergizes with DMF to kill via BIM+BAD-induced mitochondrial dysfunction and via reduced SOD2/TRX expression and ROS.

PubMed

Tavallai, Mehrad; Booth, Laurence; Roberts, Jane L; McGuire, William P; Poklepovic, Andrew; Dent, Paul

2016-04-05

We determined whether the myelofibrosis drug ruxolitinib, an inhibitor of Janus kinases 1/2 (JAK1 and JAK2), could interact with the multiple sclerosis drug dimethyl-fumarate (DMF) to kill tumor cells; studies used the in vivo active form of the drug, mono-methyl fumarate (MMF). Ruxolitinib interacted with MMF to kill brain, breast, lung and ovarian cancer cells, and enhanced the lethality of standard of care therapies such as paclitaxel and temozolomide. MMF also interacted with other FDA approved drugs to kill tumor cells including Celebrex® and Gilenya®. The combination of [ruxolitinib + MMF] inactivated ERK1/2, AKT, STAT3 and STAT5; reduced expression of MCL-1, BCL-XL, SOD2 and TRX; increased BIM expression; decreased BAD S112 S136 phosphorylation; and enhanced pro-caspase 3 cleavage. Expression of activated forms of STAT3, MEK1 or AKT each significantly reduced drug combination lethality; prevented BAD S112 S136 dephosphorylation and decreased BIM expression; and preserved TRX, SOD2, MCL-1 and BCL-XL expression. The drug combination increased the levels of reactive oxygen species in cells, and over-expression of TRX or SOD2 prevented drug combination tumor cell killing. Over-expression of BCL-XL or knock down of BAX, BIM, BAD or apoptosis inducing factor (AIF) protected tumor cells. The drug combination increased AIF : HSP70 co-localization in the cytosol but this event did not prevent AIF : eIF3A association in the nucleus.

Combinatorial drug screening and molecular profiling reveal diverse mechanisms of intrinsic and adaptive resistance to BRAF inhibition in V600E BRAF mutant melanomas

PubMed Central

Roller, Devin G.; Capaldo, Brian; Bekiranov, Stefan; Mackey, Aaron J.; Conaway, Mark R.; Petricoin, Emanuel F.; Gioeli, Daniel; Weber, Michael J.

2016-01-01

Over half of BRAFV600E melanomas display intrinsic resistance to BRAF inhibitors, in part due to adaptive signaling responses. In this communication we ask whether BRAFV600E melanomas share common adaptive responses to BRAF inhibition that can provide clinically relevant targets for drug combinations. We screened a panel of 12 treatment-naïve BRAFV600E melanoma cell lines with MAP Kinase pathway inhibitors in pairwise combination with 58 signaling inhibitors, assaying for synergistic cytotoxicity. We found enormous diversity in the drug combinations that showed synergy, with no two cell lines having an identical profile. Although the 6 lines most resistant to BRAF inhibition showed synergistic benefit from combination with lapatinib, the signaling mechanisms by which this combination generated synergistic cytotoxicity differed between the cell lines. We conclude that adaptive responses to inhibition of the primary oncogenic driver (BRAFV600E) are determined not only by the primary oncogenic driver but also by diverse secondary genetic and epigenetic changes (“back-seat drivers”) and hence optimal drug combinations will be variable. Because upregulation of receptor tyrosine kinases is a major source of drug resistance arising from diverse adaptive responses, we propose that inhibitors of these receptors may have substantial clinical utility in combination with inhibitors of the MAP Kinase pathway. PMID:26673621

Combinatorial drug screening and molecular profiling reveal diverse mechanisms of intrinsic and adaptive resistance to BRAF inhibition in V600E BRAF mutant melanomas.

PubMed

Roller, Devin G; Capaldo, Brian; Bekiranov, Stefan; Mackey, Aaron J; Conaway, Mark R; Petricoin, Emanuel F; Gioeli, Daniel; Weber, Michael J

2016-01-19

Over half of BRAFV600E melanomas display intrinsic resistance to BRAF inhibitors, in part due to adaptive signaling responses. In this communication we ask whether BRAFV600E melanomas share common adaptive responses to BRAF inhibition that can provide clinically relevant targets for drug combinations. We screened a panel of 12 treatment-naïve BRAFV600E melanoma cell lines with MAP Kinase pathway inhibitors in pairwise combination with 58 signaling inhibitors, assaying for synergistic cytotoxicity. We found enormous diversity in the drug combinations that showed synergy, with no two cell lines having an identical profile. Although the 6 lines most resistant to BRAF inhibition showed synergistic benefit from combination with lapatinib, the signaling mechanisms by which this combination generated synergistic cytotoxicity differed between the cell lines. We conclude that adaptive responses to inhibition of the primary oncogenic driver (BRAFV600E) are determined not only by the primary oncogenic driver but also by diverse secondary genetic and epigenetic changes ("back-seat drivers") and hence optimal drug combinations will be variable. Because upregulation of receptor tyrosine kinases is a major source of drug resistance arising from diverse adaptive responses, we propose that inhibitors of these receptors may have substantial clinical utility in combination with inhibitors of the MAP Kinase pathway.

In vitro cytogenetic evaluation of the particular combination of flurbiprofen and roxithromycin.

PubMed

Timocin, Taygun; Husunet, Mehmet Tahir; Valipour, Ebrahim; Norizadeh Tazehkand, Mostafa; Celik, Rima; Topaktas, Mehmet; Ila, Hasan B

2017-07-01

Flurbiprofen (FLB) (anti-inflammatory and analgesic drug) and roxithromycin (RXM) (antibiotic) were widely used in world wide. This study deals with investigation of genotoxicity, cytotoxicity, and oxidative stress effects of a particular combination of these drugs in human cultured lymphocytes. Also, DNA damaging-protective effects of combination of these drugs were analyzed on plasmid DNA. Human lymphocytes were treated with different concentrations (FLB + RXM; 10 μg/mL + 25 μg/mL, 15 μg/mL + 50 μg/mL, and 20 μg/mL + 100 μg/mL) of the drugs following by study of their genotoxic and cytotoxic effects by analysis of cytokinesis-block micronucleus test and nuclear division index, respectively. The effect of the combination in aspect of anti-oxidative and DNA damaging activity was evaluated on Pet-22b plasmid. According to our results, the combination of FLB and RXM did not show a notable genotoxic effect on cells. Although each of the substances had been shown as a cytotoxic agent by previous researchers, in this research, the combination of these drugs did not exhibit any adverse effect on cell division. FLB had DNA protection effect against H 2 O 2 while in combination with RXM had not the same effect on the plasmid.

Sinergism between alkaloids piperine and capsaicin with meglumine antimoniate against Leishmania infantum.

PubMed

Vieira-Araújo, Francisco Marcelo; Macedo Rondon, Fernanda Cristina; Pinto Vieira, Ícaro Gusmão; Pereira Mendes, Francisca Noelia; Carneiro de Freitas, José Claudio; Maia de Morais, Selene

2018-05-01

The primary choice of drugs to treat Leishmaniasis are the pentavalent antimony-based compounds, nevertheless these drugs presented undesirable side effects. However, safe natural compounds could be used in combination with these drugs to enhance their activity. The aim of this study was to evaluate the sinergism of capsaicin and piperine, isolated from Capsicum frutescens and Piper nigrum, respectively, in combination with meglumine antimoniate against Leishmania infantum promastigote and amastigote forms. Each compound was mixed with the standard drug in several percentage mixtures and tested at various concentrations. Capsaicin and piperine in combination with meglumine antimoniate (25% + 75%) showed better anti-leishmanial activity with EC 50  = 4.31 ± 0.44 e 7.25 ± 4.84 μg/mL against promastigote and amastigote forms, respectively. The results point that these spice alkaloids are suitable compounds to be administered in combinations with antileishmanial drugs to improve their action. Copyright © 2018 Elsevier Inc. All rights reserved.

Stimuli-free programmable drug release for combination chemo-therapy

NASA Astrophysics Data System (ADS)

Fan, Li; Jin, Boquan; Zhang, Silu; Song, Chaojun; Li, Quan

2016-06-01

Combinational chemotherapy capable of targeted delivery and programmable multi-drug release leads to enhanced drug efficacy, and is highly desired for cancer treatment. However, effective approaches for achieving both features in a single treatment are limited. In the present work, we demonstrated programmed delivery of both chemotherapeutic and immunotherapeutic agents with tumor cell targeting capability by using SiO2 based self-decomposable nanoparticulate systems. The programmable drug delivery is realized by manipulating drug loading configurations instead of relying on external stimuli. Both in vitro and in vivo results showed specific drug binding to FAT1-expressing colon cancer cells. The loaded dual drugs were demonstrated to be delivered in a sequential manner with specific time intervals between their peak releases, which maximize the synergistic effect of the chemotherapeutics. These features led to significantly enhanced drug efficacy and reduced system toxicity. The tumor weight decreased by 1/350, together with a moderate increase in rats' body weight, which were observed when adopting the dual drug loaded nanoparticles, as compared to those of the control groups. The present system provides a simple and feasible method for the design of targeting and combination chemotherapy with programmed drug release.Combinational chemotherapy capable of targeted delivery and programmable multi-drug release leads to enhanced drug efficacy, and is highly desired for cancer treatment. However, effective approaches for achieving both features in a single treatment are limited. In the present work, we demonstrated programmed delivery of both chemotherapeutic and immunotherapeutic agents with tumor cell targeting capability by using SiO2 based self-decomposable nanoparticulate systems. The programmable drug delivery is realized by manipulating drug loading configurations instead of relying on external stimuli. Both in vitro and in vivo results showed specific drug binding to FAT1-expressing colon cancer cells. The loaded dual drugs were demonstrated to be delivered in a sequential manner with specific time intervals between their peak releases, which maximize the synergistic effect of the chemotherapeutics. These features led to significantly enhanced drug efficacy and reduced system toxicity. The tumor weight decreased by 1/350, together with a moderate increase in rats' body weight, which were observed when adopting the dual drug loaded nanoparticles, as compared to those of the control groups. The present system provides a simple and feasible method for the design of targeting and combination chemotherapy with programmed drug release. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06305a

Advances in drug delivery system for platinum agents based combination therapy.

PubMed

Kang, Xiang; Xiao, Hai-Hua; Song, Hai-Qin; Jing, Xia-Bin; Yan, Le-San; Qi, Ruo-Gu

2015-12-01

Platinum-based anticancer agents are widely used as first-line drugs in cancer chemotherapy for various solid tumors. However, great side effects and occurrence of resistance remain as the major drawbacks for almost all the platinum drugs developed. To conquer these problems, new strategies should be adopted for platinum drug based chemotherapy. Modern nanotechnology has been widely employed in the delivery of various therapeutics and diagnostic. It provides the possibility of targeted delivery of a certain anticancer drug to the tumor site, which could minimize toxicity and optimize the drug efficacy. Here, in this review, we focused on the recent progress in polymer based drug delivery systems for platinum-based combination therapy.

21 CFR 358.760 - Labeling of permitted combinations of active ingredients for the control of dandruff.

Code of Federal Regulations, 2011 CFR

2011-04-01

... established in the statement of identity sections of the applicable OTC drug monographs. (1) Combinations of... ingredient in the directions sections of the applicable OTC drug monographs, unless otherwise stated in this... established for any individual ingredient in the applicable OTC drug monograph(s), and may not provide for use...

21 CFR 358.760 - Labeling of permitted combinations of active ingredients for the control of dandruff.

Code of Federal Regulations, 2010 CFR

2010-04-01

... established in the statement of identity sections of the applicable OTC drug monographs. (1) Combinations of... ingredient in the directions sections of the applicable OTC drug monographs, unless otherwise stated in this... established for any individual ingredient in the applicable OTC drug monograph(s), and may not provide for use...

Combinations of Drugs in the Treatment of Obesity

PubMed Central

Halpern, Bruno; Oliveira, Eduardo S. L.; Faria, André M.; Halpern, Alfredo; de Melo, Maria Edna; Cercato, Cintia; Mancini, Marcio C.

2010-01-01

Obesity is a chronic disease associated with excess morbidity and mortality. Clinical treatment, however, currently offers disappointing results, with very high rates of weight loss failure or weight regain cycles, and only two drugs (orlistat and sibutramine) approved for long-term use. Drugs combinations can be an option for its treatment but, although widely used in clinical practice, very few data are available in literature for its validation. Our review focuses on the rationale for their use, with advantages and disadvantages; on combinations often used, with or without studies; and on new perspectives of combinations being studied mainly by the pharmaceutical industry. PMID:27713360

A clinical pharmacological assessment of doxazosin and enalapril in combination.

PubMed

Bainbridge, A D; Meredith, P A; Elliott, H L

1993-12-01

This study in 12 normotensive males investigated potential pharmacokinetic and pharmacodynamic interaction mechanisms resulting from the combination of enalapril and doxazosin. Blood pressure reductions were consistently greater with the combination but there was no evidence of a significant pharmacodynamic interaction (as determined by heart rate changes, renal function tests or by pressor responsiveness indices) and there was no evidence of a pharmacokinetic interaction with either drug. Responsiveness to each drug i.e. blood pressure reduction per unit drug concentration was not significantly altered in the combination regimen. In conclusion, these results suggest that the combination of enalapril and doxazosin produces a usefully additive hypotensive effect but there was no evidence of synergism i.e an effect which was more than additive.

Practical Applications for Single Pill Combinations in the Cardiovascular Continuum

PubMed Central

Iellamo, Ferdinando; Werdan, Karl; Narkiewicz, Krzysztof; Rosano, Giuseppe

2017-01-01

Despite the availability of new drugs and devices, the treatment of cardiovascular disease remains suboptimal. Single-pill combination therapy offers a number of potential advantages. It can combine different classes of drugs to increase efficacy while mitigating the risks of treatment-related adverse events, reduce pill burden, lower medical cost, and improve patient adherence. Furthermore, in hypertension, single pill combinations include standard to lower doses of each drug than would be necessary to achieve goals with monotherapy, which may explain their better tolerability compared with higher dose monotherapy. Combination therapy is now established in the treatment of hypertension. In ischaemic heart disease, the concept of a preventative polypill has been studied, but its benefits have not been established conclusively. However, the combination of ivabradine and beta-blockers has proven efficacy in patients with stable angina pectoris. This combination has also demonstrated benefits in patients with chronic heart failure. PMID:28785474

Combination of Anti-angiogenesis with Chemotherapy for More Effective Cancer Treatment*

PubMed Central

Ma, Jie; Waxman, David J.

2008-01-01

Angiogenesis is a hallmark of tumor development and metastasis and is now a validated target for cancer treatment. Overall, however, the survival benefits of anti-angiogenic drugs have, thus far, been rather modest, stimulating interest in developing more effective ways to combine anti-angiogenic drugs with established chemotherapies. This review discusses recent progress and emerging challenges in this field; interactions between anti-angiogenic drugs and conventional chemotherapeutic agents are examined, and strategies for the optimization of combination therapies are discussed. Anti-angiogenic drugs such as the anti-VEGF antibody bevacizumab can induce a functional normalization of the tumor vasculature that is transient and can potentiate the activity of co-administered chemoradiotherapies. However, chronic angiogenesis inhibition typically reduces tumor uptake of co-administered chemotherapeutics, indicating a need to explore new approaches, including intermittent treatment schedules and provascular strategies to increase chemotherapeutic drug exposure. In cases where anti-angiogenesis-induced tumor cell starvation augments the intrinsic cytotoxic effects of a conventional chemotherapeutic drug, combination therapy may increase anti-tumor activity despite a decrease in cytotoxic drug exposure. As new angiogenesis inhibitors enter the clinic, reliable surrogate markers are needed to monitor the progress of anti-angiogenic therapies and to identify responsive patients. New targets for anti-angiogenesis continue to be discovered, increasing the opportunities to interdict tumor angiogenesis and circumvent resistance mechanisms that may emerge with chronic use of these drugs. PMID:19074844

New psychoactive substances as adulterants of controlled drugs. A worrying phenomenon?

PubMed

Giné, Claudio Vidal; Espinosa, Iván Fornís; Vilamala, Mireia Ventura

2014-01-01

The use of new psychoactive substances (NPS) as adulterants has received little attention in the literature. In this paper, results from Energy Control's drug checking service documenting the use of NPS as adulterants of controlled drugs are presented, and some reflections about possible explanations for this new phenomenon, potential risks for users, and challenges that it poses are discussed. From 2009 to 2012, 24 NPS belonging to several chemical classes such as phenethylamines, substituted cathinones, tryptamines, and methoxetamine were identified in 173 samples believed to be MDMA, amphetamine, ketamine, cocaine, mescaline, or methamphetamine. The NPS adulterant most frequently observed was 2-(4-bromo-2,5-dimethoxyphenyl)ethanamine (2C-B) followed by 1-(4-fluorophenyl)propan-2-amine (4-FA). Sixty-nine different combinations of substances were detected: 20 involving a controlled drug combined with an NPS, and 49 involving one or more NPS that substituted the controlled drug. As these combinations could pose substantial risks to users, the need to improve knowledge about toxicity associated with these combinations, and the danger of these substances being incorporated into the products of illegal markets, are highlighted. Drug checking services and the European Union's early-warning system operated by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and Europol can play an important role in reducing the harm associated with this phenomenon. Copyright © 2014 John Wiley & Sons, Ltd.

Efficacy and Tolerability of Antihypertensive Drugs in Diabetic and Nondiabetic Patients.

PubMed

Aslam, Maria; Ahmad, Mobasher; Mobasher, Fizza

2017-01-01

The aim of the study was to compare the efficacy and tolerability of different classes of antihypertensive drugs in diabetic and nondiabetic patients (NDPs) with essential hypertension. The study was conducted in Mayo Hospital, Punjab Institute of Cardiology, and National Defence Hospital, Lahore, Pakistan, on 200 hypertensive patients with diabetes and 230 hypertensive patients without (Three hospitals) diabetes. Both male and female patients of age between 30 and 80 years with systolic blood pressure (SBP) above 130 mmHg and diastolic blood pressure (DBP) above 80 mmHg were enrolled in the study. Angiotensin converting enzyme inhibitors (ACEI), beta-blocker (βB), calcium-channel blocker (CCB), diuretics (D), angiotensin receptor blocker (ARB) as well as α-blocker classes of antihypertensive drugs were used. These drugs were used as monotherapy as well as combination therapy. The study was conducted for 4 months (July-October). After 4 months, patients were assessed for efficacy by monitoring blood pressure (BP) and tolerability by assessing safety profile on renal function, liver function as well as lipid profile. Significant control in mean BP by all drug groups was observed in "both groups that is patients with diabetes and without diabetes." The efficacy and tolerability data revealed that in diabetic patients with hypertension, the highest decrease in SBP and DBP was observed using monotherapy with ACEI, two-drug combination therapy with ACEI plus diuretic, ARBs plus diuretic, ACEI plus CCBs, three-drug combination therapy with ACEI plus CCBs plus diuretic, and four drug combination therapy with ACEI plus CCBs plus diuretic plus βBs, ARB's plus CCBs plus diuretic plus βBs while in NDPs, monotherapy with diuretic, two-drug combination therapy with ACEI plus CCBs, ACEI plus βBs, three-drug combination therapy with βBs plus ACEI plus D was found more effective in controlling SBP as well as DBP. Adverse effects observed were dry cough, pedal edema, dizziness, muscular cramps, constipation, palpitations, sweating, vertigo, tinnitus, paresthesia, and sexual dysfunction. All classes of antihypertensives were found to control blood pressure significantly in both groups of patients that is diabetic patients with hypertesion and non-diabetic patients with hypertension.

Combined targeting of STAT3 and STAT5: a novel approach to overcome drug resistance in chronic myeloid leukemia.

PubMed

Gleixner, Karoline V; Schneeweiss, Mathias; Eisenwort, Gregor; Berger, Daniela; Herrmann, Harald; Blatt, Katharina; Greiner, Georg; Byrgazov, Konstantin; Hoermann, Gregor; Konopleva, Marina; Waliul, Islam; Cumaraswamy, Abbarna A; Gunning, Patrick T; Maeda, Hiroshi; Moriggl, Richard; Deininger, Michael; Lion, Thomas; Andreeff, Michael; Valent, Peter

2017-09-01

In chronic myeloid leukemia, resistance against BCR-ABL1 tyrosine kinase inhibitors can develop because of BCR-ABL1 mutations, activation of additional pro-oncogenic pathways, and stem cell resistance. Drug combinations covering a broad range of targets may overcome resistance. CDDO-Me (bardoxolone methyl) is a drug that inhibits the survival of leukemic cells by targeting different pro-survival molecules, including STAT3. We found that CDDO-Me inhibits proliferation and survival of tyrosine kinase inhibitor-resistant BCR-ABL1 + cell lines and primary leukemic cells, including cells harboring BCR-ABL1 T315I or T315I + compound mutations. Furthermore, CDDO-Me was found to block growth and survival of CD34 + /CD38 - leukemic stem cells (LSC). Moreover, CDDO-Me was found to produce synergistic growth-inhibitory effects when combined with BCR-ABL1 tyrosine kinase inhibitors. These drug-combinations were found to block multiple signaling cascades and molecules, including STAT3 and STAT5. Furthermore, combined targeting of STAT3 and STAT5 by shRNA and STAT5-targeting drugs also resulted in synergistic growth-inhibition, pointing to a new efficient concept of combinatorial STAT3 and STAT5 inhibition. However, CDDO-Me was also found to increase the expression of heme-oxygenase-1, a heat-shock-protein that triggers drug resistance and cell survival. We therefore combined CDDO-Me with the heme-oxygenase-1 inhibitor SMA-ZnPP, which also resulted in synergistic growth-inhibitory effects. Moreover, SMA-ZnPP was found to sensitize BCR-ABL1 + cells against the combination 'CDDO-Me+ tyrosine kinase inhibitor'. Together, combined targeting of STAT3, STAT5, and heme-oxygenase-1 overcomes resistance in BCR-ABL1 + cells, including stem cells and highly resistant sub-clones expressing BCR-ABL1 T315I or T315I-compound mutations. Whether such drug-combinations are effective in tyrosine kinase inhibitor-resistant patients with chronic myeloid leukemia remains to be elucidated. Copyright© 2017 Ferrata Storti Foundation.

The synergistic effects of Apatinib combined with cytotoxic chemotherapeutic agents on gastric cancer cells and in a fluorescence imaging gastric cancer xenograft model.

PubMed

Feng, Jiuhuan; Qin, Shukui

2018-01-01

Methylsulfonic apatinib (hereinafter referred to as Apatinib) is a small-molecule angiogenesis inhibitor highly and selectively targeted to vascular endothelial growth factor receptor-2. At present, a series of basic and clinical studies have confirmed that Apatinib mono-therapy can inhibit the growth of different carcinomas. Our experiment aimed to determine whether there is a synergistic effect between the combination of the traditional cytotoxic chemotherapy drugs paclitaxel (TAX), oxaliplatin (L-OHP), 5-fluorouracil (5-FU), and Apatinib. We evaluated the combined effect using cytological experiments and a fluorescence imaging xenograft model. In vitro, the inhibition of cell proliferation increased notably when Apatinib was combined with TAX, L-OHP, and 5-FU. Then, for the mechanistic research, we selected the optimal dose of drugs that also had a synergistic effect. Apatinib combined with the aforementioned drugs, especially the combination of Apatinib and 5-FU, decreased the invasion and migration ability of the cells and increased the apoptosis ratio; expression of the anti-apoptotic protein Bcl-2 significantly decreased, and expression of the pro-apoptotic protein Bax increased. In vivo, when Apatinib was combined with TAX, L-OHP, and 5-FU, the volume of the xenograft model was significantly inhibited, the strength of the green fluorescence was weakened and the microvessel density decreased. The combination of Apatinib with TAX and 5-FU was synergistic (coefficient of drug interaction <1); the combination effect of Apatinib and L-OHP was only additive, with a shorter associated survival time. The combination of Apatinib and classical chemotherapy drugs may be an optimal choice for gastric cancer treatment.

The synergistic effects of Apatinib combined with cytotoxic chemotherapeutic agents on gastric cancer cells and in a fluorescence imaging gastric cancer xenograft model

PubMed Central

Feng, Jiuhuan; Qin, Shukui

2018-01-01

Introduction Methylsulfonic apatinib (hereinafter referred to as Apatinib) is a small-molecule angiogenesis inhibitor highly and selectively targeted to vascular endothelial growth factor receptor-2. At present, a series of basic and clinical studies have confirmed that Apatinib mono-therapy can inhibit the growth of different carcinomas. Our experiment aimed to determine whether there is a synergistic effect between the combination of the traditional cytotoxic chemotherapy drugs paclitaxel (TAX), oxaliplatin (L-OHP), 5-fluorouracil (5-FU), and Apatinib. Materials and methods We evaluated the combined effect using cytological experiments and a fluorescence imaging xenograft model. In vitro, the inhibition of cell proliferation increased notably when Apatinib was combined with TAX, L-OHP, and 5-FU. Then, for the mechanistic research, we selected the optimal dose of drugs that also had a synergistic effect. Apatinib combined with the aforementioned drugs, especially the combination of Apatinib and 5-FU, decreased the invasion and migration ability of the cells and increased the apoptosis ratio; expression of the anti-apoptotic protein Bcl-2 significantly decreased, and expression of the pro-apoptotic protein Bax increased. In vivo, when Apatinib was combined with TAX, L-OHP, and 5-FU, the volume of the xenograft model was significantly inhibited, the strength of the green fluorescence was weakened and the microvessel density decreased. Results The combination of Apatinib with TAX and 5-FU was synergistic (coefficient of drug interaction <1); the combination effect of Apatinib and L-OHP was only additive, with a shorter associated survival time. Conclusion The combination of Apatinib and classical chemotherapy drugs may be an optimal choice for gastric cancer treatment. PMID:29872316

Preparation and characterization of fast dissolving pullulan films containing BCS class II drug nanoparticles for bioavailability enhancement.

PubMed

Krull, Scott M; Ma, Zhelun; Li, Meng; Davé, Rajesh N; Bilgili, Ecevit

2016-01-01

The aim of this study is to assess pullulan as a novel steric stabilizer during the wet-stirred media milling (WSMM) of griseofulvin, a model poorly water-soluble drug, and as a film-former in the preparation of strip films via casting-drying the wet-milled drug suspensions for dissolution and bioavailability enhancement. To this end, pullulan films, with xanthan gum (XG) as thickening agent and glycerin as plasticizer, were loaded with griseofulvin nanoparticles prepared by WSMM using pullulan in combination with sodium dodecyl sulfate (SDS) as an ionic stabilizer. The effects of drug loading and milling time on the particle size and suspension stability were investigated, as well as XG concentration and casting thickness on film properties and dissolution rate. The nanosuspensions prepared with pullulan-SDS combination were relatively stable over 7 days; hence, this combination was used for the film preparation. All pullulan-based strip films exhibited excellent content uniformity (most <3% RSD) despite containing only 0.3-1.3 mg drug, which was ensured by the use of precursor suspensions with >5000 cP viscosity. USP IV dissolution tests revealed fast/immediate drug release (t80 < 30 min) from films <120 μm thick. Thinner films, films with lower XG loading, or smaller drug particles led to faster drug dissolution, while drug loading had no discernible effect. Overall, these results suggest that pullulan may serve as an acceptable stabilizer for media milling in combination with surfactant as well as a fast-dissolving film former for the fast release of poorly water-soluble drug nanoparticles.

Drugs Approved for Testicular Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for testicular cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

Drugs Approved for Cervical Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for cervical cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

Drugs Approved for Hodgkin Lymphoma

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for Hodgkin lymphoma. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

Drugs Approved for Myeloproliferative Neoplasms

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for myeloproliferative neoplasms. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

[New drugs for small animals in 2017].

PubMed

Emmerich, Ilka Ute

2018-04-01

In 2017 the active pharmaceutical ingredient Lokivetmab (Cytopoint®), a caninized anti-canine Interleukin 31 monoclonal antibody, was released on the German market for small animals. One substance was authorized for an additional species. Sarolaner, an ectoparasiticide of the isoxazoline group, is now authorized for use in combination with Selamectin (Stronghold® Plus) additionally for cats. The testosterone derivate Nandrolone (Nandrosol®) and the combination of the benzodiazepine Zolazepam with the "dissociative anesthetic" Tiletamine (Zoletil®) were once again authorized. Furthermore, two veterinary drugs with a new combination of active ingredients, one drug with a new active ingredient and two veterinary drugs with a new pharmaceutical form have been launched on the market for small animals. Schattauer GmbH.

A Drug Combination Screen Identifies Drugs Active against Amoxicillin-Induced Round Bodies of In Vitro Borrelia burgdorferi Persisters from an FDA Drug Library

PubMed Central

Feng, Jie; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G.; Zhang, Ying

2016-01-01

Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10–20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under experimental stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that appear resistant in vitro to customary first-line antibiotics for Lyme disease. To identify more effective drugs with activity against the round body form of B. burgdorferi, we established a round body persister model induced by exposure to amoxicillin (50 μg/ml) and then screened the Food and Drug Administration drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven individual drugs scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. In this amoxicillin-induced round body model, some drug candidates such as daptomycin and clofazimine also displayed enhanced activity which was similar to a previous screen against stationary phase B. burgdorferi persisters not exposure to amoxicillin. Additional candidate drugs active against round bodies identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against amoxicillin-induced round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi persisters in vitro, even when pre-treated with amoxicillin. These findings may have implications for improved treatment of Lyme disease. PMID:27242757

A Drug Combination Screen Identifies Drugs Active against Amoxicillin-Induced Round Bodies of In Vitro Borrelia burgdorferi Persisters from an FDA Drug Library.

PubMed

Feng, Jie; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G; Zhang, Ying

2016-01-01

Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10-20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under experimental stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that appear resistant in vitro to customary first-line antibiotics for Lyme disease. To identify more effective drugs with activity against the round body form of B. burgdorferi, we established a round body persister model induced by exposure to amoxicillin (50 μg/ml) and then screened the Food and Drug Administration drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven individual drugs scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. In this amoxicillin-induced round body model, some drug candidates such as daptomycin and clofazimine also displayed enhanced activity which was similar to a previous screen against stationary phase B. burgdorferi persisters not exposure to amoxicillin. Additional candidate drugs active against round bodies identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against amoxicillin-induced round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi persisters in vitro, even when pre-treated with amoxicillin. These findings may have implications for improved treatment of Lyme disease.

Prediction of clinical response to drugs in ovarian cancer using the chemotherapy resistance test (CTR-test).

PubMed

Kischkel, Frank Christian; Meyer, Carina; Eich, Julia; Nassir, Mani; Mentze, Monika; Braicu, Ioana; Kopp-Schneider, Annette; Sehouli, Jalid

2017-10-27

In order to validate if the test result of the Chemotherapy Resistance Test (CTR-Test) is able to predict the resistances or sensitivities of tumors in ovarian cancer patients to drugs, the CTR-Test result and the corresponding clinical response of individual patients were correlated retrospectively. Results were compared to previous recorded correlations. The CTR-Test was performed on tumor samples from 52 ovarian cancer patients for specific chemotherapeutic drugs. Patients were treated with monotherapies or drug combinations. Resistances were classified as extreme (ER), medium (MR) or slight (SR) resistance in the CTR-Test. Combination treatment resistances were transformed by a scoring system into these classifications. Accurate sensitivity prediction was accomplished in 79% of the cases and accurate prediction of resistance in 100% of the cases in the total data set. The data set of single agent treatment and drug combination treatment were analyzed individually. Single agent treatment lead to an accurate sensitivity in 44% of the cases and the drug combination to 95% accuracy. The detection of resistances was in both cases to 100% correct. ROC curve analysis indicates that the CTR-Test result correlates with the clinical response, at least for the combination chemotherapy. Those values are similar or better than the values from a publication from 1990. Chemotherapy resistance testing in vitro via the CTR-Test is able to accurately detect resistances in ovarian cancer patients. These numbers confirm and even exceed results published in 1990. Better sensitivity detection might be caused by a higher percentage of drug combinations tested in 2012 compared to 1990. Our study confirms the functionality of the CTR-Test to plan an efficient chemotherapeutic treatment for ovarian cancer patients.

Disease-modifying antirheumatic drugs other than methotrexate in rheumatoid arthritis and seronegative arthritis.

PubMed

Nandi, Pradip; Kingsley, Gabrielle H; Scott, David L

2008-05-01

To outline recent research findings with nonmethotrexate disease-modifying antirheumatic drugs in rheumatoid arthritis and seronegative arthritis spanning systematic reviews, randomized controlled trials, observational clinical practice trials and assessments of adverse effects. Systematic reviews show no important differences between methotrexate, leflunomide and sulfasalazine monotherapies; early disease-modifying antirheumatic drug therapy reduces erosive progression. Observational studies show that nonmethotrexate disease-modifying antirheumatic drugs are widely prescribed; their usage has increased in the biologic era. A systemic review also showed patients who failed monotherapy benefited from disease-modifying antirheumatic drug combinations without excess toxicity. Randomized controlled trials of intensive initial disease-modifying antirheumatic drug combinations showed they reduce synovitis and erosive damage, especially when used with steroids. The subsequent sequence of disease-modifying antirheumatic drugs and the value of changing disease-modifying antirheumatic drug monotherapies or stepping-up to combination disease-modifying antirheumatic drugs are, however, unresolved. The adverse risks of nonmethotrexate disease-modifying antirheumatic drugs have been evaluated, including infections and lung disease; patient-related risks seem more important than drug-related risks, though several disease-modifying antirheumatic drugs increase both types of adverse reactions. Two limitations of nonmethotrexate disease-modifying antirheumatic drugs are reduced impact on comorbidities like cardiovascular disease and reduced patient and clinician preferences for these treatments. Nonmethotrexate disease-modifying antirheumatic drugs are effective, relatively well tolerated and widely used. Their role in intensive treatment strategies in early rheumatoid arthritis appears of crucial importance.

Penetration of topical, oral, and combined administered ofloxacin into the subretinal fluid

PubMed Central

Cekic, O.; Batman, C.; Yasar, U.; Totan, Y.; Basci, N.; Bozkurt, A.; Zilelioglu, O.; Kayaalp, S

1999-01-01

AIMS—To assess the subretinal fluid (SRF) levels of ofloxacin following topical, oral or combined administration.
METHODS—31 patients undergoing conventional retinal reattachment surgery were randomly assigned to three groups. Nine patients received topical ofloxacin, 11 patients received oral ofloxacin, and the other 11 patients received combined administration. Collected SRF samples were analysed for drug level by using high performance liquid chromatography.
RESULTS—SRF drug levels after oral and combined administration were significantly higher than that after topical administration (p=0.0002 and p=0.0002, respectively) while there was no significant difference between oral and combined administration (p=0.0844).
CONCLUSIONS—Ocular bioavailability of ofloxacin in SRF after oral and combined administration is equivalent. The addition of oral ofloxacin to topical therapy increased drug SRF penetration sixfold.

 PMID:10502583

Ginseng and Anticancer Drug Combination to Improve Cancer Chemotherapy: A Critical Review

PubMed Central

Chen, Shihong; Huang, Ying; O'Barr, Stephen A.; Wong, Rebecca A.; Chow, Moses Sing Sum

2014-01-01

Ginseng, a well-known herb, is often used in combination with anticancer drugs to enhance chemotherapy. Its wide usage as well as many documentations are often cited to support its clinical benefit of such combination therapy. However the literature based on objective evidence to make such recommendation is still lacking. The present review critically evaluated relevant studies reported in English and Chinese literature on such combination. Based on our review, we found good evidence from in vitro and in vivo animal studies showing enhanced antitumor effect when ginseng is used in combination with some anticancer drugs. However, there is insufficient clinical evidence of such benefit as very few clinical studies are available. Future research should focus on clinically relevant studies of such combination to validate the utility of ginseng in cancer. PMID:24876866

Optimal control of malaria: combining vector interventions and drug therapies.

PubMed

Khamis, Doran; El Mouden, Claire; Kura, Klodeta; Bonsall, Michael B

2018-04-24

The sterile insect technique and transgenic equivalents are considered promising tools for controlling vector-borne disease in an age of increasing insecticide and drug-resistance. Combining vector interventions with artemisinin-based therapies may achieve the twin goals of suppressing malaria endemicity while managing artemisinin resistance. While the cost-effectiveness of these controls has been investigated independently, their combined usage has not been dynamically optimized in response to ecological and epidemiological processes. An optimal control framework based on coupled models of mosquito population dynamics and malaria epidemiology is used to investigate the cost-effectiveness of combining vector control with drug therapies in homogeneous environments with and without vector migration. The costs of endemic malaria are weighed against the costs of administering artemisinin therapies and releasing modified mosquitoes using various cost structures. Larval density dependence is shown to reduce the cost-effectiveness of conventional sterile insect releases compared with transgenic mosquitoes with a late-acting lethal gene. Using drug treatments can reduce the critical vector control release ratio necessary to cause disease fadeout. Combining vector control and drug therapies is the most effective and efficient use of resources, and using optimized implementation strategies can substantially reduce costs.

Enhanced effect of losartan and rosuvastatin on neointima hyperplasia.

PubMed

Yi, Inseon; Lee, Jung-Jin; Park, Jeong-Sook; Zhang, Wei Yun; Kim, In-Su; Kim, Yohan; Shin, Chang-Yong; Kim, Hyung Sik; Myung, Chang-Seon

2010-04-01

The beneficial effects of losartan and rosuvastatin on neointimal formation have been well characterized, but little is known about the combined treatment benefit of these two drugs. This study was designed to investigate the synergistic effect of losartan combined with rosuvastatin on the magnitude of protective action in vascular injury mediated by cuff-induced neointimal formation model in vivo. Losartan at 20 mg/kg or rosuvastatin at 40 mg/kg significantly decreased both the neointimal formation and BrdU-positive cells in neointima, indicating the inhibition of cell proliferation including a progress of DNA synthesis. The combination treatment used lower doses of losartan with rosuvastatin (10 + 20 & 5 + 10 mg/kg, respectively) that proved to be significant in decreasing the neointimal formation and BrdU incorporation. These results were comparable to the diminution attained with monotherapy of either drug in higher doses. Interaction index measured by isobolar method indicated drug synergism in these two combinations of both drugs at lower doses. Therefore, the administration of losartan and rosuvastatin in combination with low doses synergistically decreased in cuff-induced neointimal formation by reducing cell proliferation, suggesting that this drug synergism may be fully effective with, lower adverse effects, for the treatment of vascular remodeling such as restenosis.

Long-acting combination anti-HIV drug suspension enhances and sustains higher drug levels in lymph node cells than in blood cells and plasma.

PubMed

Kraft, John C; McConnachie, Lisa A; Koehn, Josefin; Kinman, Loren; Collins, Carol; Shen, Danny D; Collier, Ann C; Ho, Rodney J Y

2017-03-27

The aim of the present study was to determine whether a combination of anti-HIV drugs - tenofovir (TFV), lopinavir (LPV) and ritonavir (RTV) - in a lipid-stabilized nanosuspension (called TLC-ART101) could enhance and sustain intracellular drug levels and exposures in lymph node and blood cells above those in plasma. Four macaques were given a single dose of TLC-ART101 subcutaneously. Drug concentrations in plasma and mononuclear cells of the blood (PBMCs) and lymph nodes (LNMCs) were analysed using a validated combination LC-MS/MS assay. For the two active drugs (TFV, LPV), plasma and PBMC intracellular drug levels persisted for over 2 weeks; PBMC drug exposures were three- to four-fold higher than those in plasma. Apparent terminal half-lives (t1/2) of TFV and LPV were 65.3 and 476.9 h in plasma, and 169.1 and 151.2 h in PBMCs. At 24 and 192 h, TFV and LPV drug levels in LNMCs were up to 79-fold higher than those in PBMCs. Analysis of PBMC intracellular TFV and its active metabolite TFV-diphosphate (TFV-DP) indicated that intracellular exposures of total TFV and TFV-DP were markedly higher and persisted longer than in humans and macaques dosed with oral TFV prodrugs, tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF). A simple, scalable three-drug combination, lipid-stabilized nanosuspension exhibited persistent drug levels in cells of lymph nodes and the blood (HIV host cells) and in plasma. With appropriate dose adjustment, TLC-ART101 may be a useful HIV treatment with a potential to impact residual virus in lymph nodes.

The story of artesunate–mefloquine (ASMQ), innovative partnerships in drug development: case study

PubMed Central

2013-01-01

Background The Drugs for Neglected Diseases initiative (DNDi) is a not-for profit organization committed to providing affordable medicines and access to treatments in resource-poor settings. Traditionally drug development has happened “in house” within pharmaceutical companies, with research and development costs ultimately recuperated through drug sales. The development of drugs for the treatment of neglected tropical diseases requires a completely different model that goes beyond the scope of market-driven research and development. Artesunate and mefloquine are well-established drugs for the treatment of uncomplicated malaria, with a strong safety record based on many years of field-based studies and use. The administration of such artemisinin-based combination therapy in a fixed-dose combination is expected to improve patient compliance and to reduce the risk of emerging drug resistance. Case description DNDi developed an innovative approach to drug development, reliant on strong collaborations with a wide range of partners from the commercial world, academia, government institutions and NGOs, each of which had a specific role to play in the development of a fixed dose combination of artesunate and mefloquine. Discussion and evaluation DNDi undertook the development of a fixed-dose combination of artesunate with mefloquine. Partnerships were formed across five continents, addressing formulation, control and production through to clinical trials and product registration, resulting in a safe and efficacious fixed dose combination treatment which is now available to treat patients in resource-poor settings. The south-south technology transfer of production from Farmanguinhos/Fiocruz in Brazil to Cipla Ltd in India was the first of its kind. Of additional benefit was the increased capacity within the knowledge base and infrastructure in developing countries. Conclusions This collaborative approach to drug development involving international partnerships and independent funding mechanisms is a powerful new way to develop drugs for tropical diseases. PMID:23433060

Permeation of Therapeutic Drugs in Different Formulations across the Airway Epithelium In Vitro

PubMed Central

Meindl, Claudia; Stranzinger, Sandra; Dzidic, Neira; Salar-Behzadi, Sharareh; Mohr, Stefan; Zimmer, Andreas; Fröhlich, Eleonore

2015-01-01

Background Pulmonary drug delivery is characterized by short onset times of the effects and an increased therapeutic ratio compared to oral drug delivery. This delivery route can be used for local as well as for systemic absorption applying drugs as single substance or as a fixed dose combination. Drugs can be delivered as nebulized aerosols or as dry powders. A screening system able to mimic delivery by the different devices might help to assess the drug effect in the different formulations and to identify potential interference between drugs in fixed dose combinations. The present study evaluates manual devices used in animal studies for their suitability for cellular studies. Methods Calu-3 cells were cultured submersed and in air-liquid interface culture and characterized regarding mucus production and transepithelial electrical resistance. The influence of pore size and material of the transwell membranes and of the duration of air-liquid interface culture was assessed. Compounds were applied in solution and as aerosols generated by MicroSprayer IA-1C Aerosolizer or by DP-4 Dry Powder Insufflator using fluorescein and rhodamine 123 as model compounds. Budesonide and formoterol, singly and in combination, served as examples for drugs relevant in pulmonary delivery. Results and Conclusions Membrane material and duration of air-liquid interface culture had no marked effect on mucus production and tightness of the cell monolayer. Co-application of budesonide and formoterol, applied in solution or as aerosol, increased permeation of formoterol across cells in air-liquid interface culture. Problems with the DP-4 Dry Powder Insufflator included compound-specific delivery rates and influence on the tightness of the cell monolayer. These problems were not encountered with the MicroSprayer IA-1C Aerosolizer. The combination of Calu-3 cells and manual aerosol generation devices appears suitable to identify interactions of drugs in fixed drug combination products on permeation. PMID:26274590

In vitro activity of nicotinamide/antileishmanial drug combinations.

PubMed

Gazanion, Elodie; Vergnes, Baptiste; Seveno, Marie; Garcia, Deborah; Oury, Bruno; Ait-Oudhia, Khatima; Ouaissi, Ali; Sereno, Denis

2011-01-01

To improve the management of leishmaniasis, new drugs and/or alternative therapeutic strategies are required. Combination therapy of antileishmanial drugs is currently considered as one of the most rational approaches to lower treatment failure rate and limit drug resistance spreading. Nicotinamide (NAm), also known as vitamin B3 that is already is used in human therapy, exerts in vitro antileishmanial activity. Drug combination studies, performed on L. infantum axenic amastigotes, revealed that NAm significantly improves the antileishmanial activity of trivalent antimony in a synergistic manner while it shows additive activity with amphotericin B and slightly antagonizes pentamidine activity. NAm also significantly increases the toxicity of pentavalent antimony against the intracellular forms of L. infantum, L. amazonensis and L. braziliensis. The potential of NAm to be used as adjuvant during leishmaniasis chemotherapy is further discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Search Algorithms as a Framework for the Optimization of Drug Combinations

PubMed Central

Coquin, Laurence; Schofield, Jennifer; Feala, Jacob D.; Reed, John C.; McCulloch, Andrew D.; Paternostro, Giovanni

2008-01-01

Combination therapies are often needed for effective clinical outcomes in the management of complex diseases, but presently they are generally based on empirical clinical experience. Here we suggest a novel application of search algorithms—originally developed for digital communication—modified to optimize combinations of therapeutic interventions. In biological experiments measuring the restoration of the decline with age in heart function and exercise capacity in Drosophila melanogaster, we found that search algorithms correctly identified optimal combinations of four drugs using only one-third of the tests performed in a fully factorial search. In experiments identifying combinations of three doses of up to six drugs for selective killing of human cancer cells, search algorithms resulted in a highly significant enrichment of selective combinations compared with random searches. In simulations using a network model of cell death, we found that the search algorithms identified the optimal combinations of 6–9 interventions in 80–90% of tests, compared with 15–30% for an equivalent random search. These findings suggest that modified search algorithms from information theory have the potential to enhance the discovery of novel therapeutic drug combinations. This report also helps to frame a biomedical problem that will benefit from an interdisciplinary effort and suggests a general strategy for its solution. PMID:19112483

Antiprotozoal treatment of canine babesiosis.

PubMed

Baneth, Gad

2018-04-30

Canine babesiosis is a tick-borne disease caused by several Babesia spp. which have different susceptebility to anti-protozoal drugs. A few drugs and drug combinations are used in the treatment of canine babesiosis often without complete parasite elimination leaving treated dogs as carriers which could relapse with clinical disease and also transmit infection further. Although the large form canine babesial species Babesia canis, Babesia vogeli and Babesia rossi are sensitive to the aromatic diamidines imidocarb dipropionate and diminazene aceturate, small form species such as Babesia gibsoni, Babesia conradae and Babesia vulpes (Theileria annae) are relatively resistant to these drugs and are treated with the combination of the hydroxynaphthoquinone atovaquone and the antibiotic azithromycin. Azithromycin and other antibiotics that have anti-protozoal properties target the apicoplast, a relict plastid found in protozoa, and exert a delayed death effect. The triple combination of clindamycin, diminazene aceturate and imidocarb dipropionate is also effective against B. gibsoni and used to treat atovaquone-resistant strains of this species. Novel drugs and the synergistic effects of drug combinations against Babesia infection should be explored further to find new treatments for canine babesiosis. Copyright © 2018 The Author. Published by Elsevier B.V. All rights reserved.

Drugs Approved for Leukemia

Cancer.gov

This page lists cancer drugs approved by the FDA for use in leukemia. The drug names link to NCI's Cancer Drug Information summaries. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

HIV-1 reverse transcriptase and antiviral drug resistance. Part 2.

PubMed

Das, Kalyan; Arnold, Eddy

2013-04-01

Structures of RT and its complexes combined with biochemical and clinical data help in illuminating the molecular mechanisms of different drug-resistance mutations. The NRTI drugs that are used in combinations have different primary mutation sites. RT mutations that confer resistance to one drug can be hypersensitive to another RT drug. Structure of an RT-DNA-nevirapine complex revealed how NNRTI binding forbids RT from forming a polymerase competent complex. Collective knowledge about various mechanisms of drug resistance by RT has broader implications for understanding and targeting drug resistance in general. In Part 1, we discussed the role of RT in developing HIV-1 drug resistance, structural and functional states of RT, and the nucleoside/nucleotide analog (NRTI) and non-nucleoside (NNRTI) drugs used in treating HIV-1 infections. In this part, we discuss structural understanding of various mechanisms by which RT confers antiviral drug resistance. Copyright © 2013 Elsevier B.V. All rights reserved.

Antiretroviral drug treatment of CNS HIV-1 infection.

PubMed

Yilmaz, Aylin; Price, Richard W; Gisslén, Magnus

2012-02-01

The advent of combination antiretroviral treatment has had a profound impact on CNS HIV infection and its clinical complications, but neurological impairment still occurs in patients on systemically effective combination therapy, and in some patients it may be important to consider antiretroviral drug entry and effects within the CNS. There are now data on the CNS exposure for most antiretroviral drugs. This review focuses on the CNS pharmacokinetics and pharmacodynamics of antiretroviral drugs in humans, and also discusses controversies in this field.

Synergistic Inhibition of Her2/neu and p53-MDM2 Pathways. Addendum

DTIC Science & Technology

2007-09-01

Therefore, combination of drugs targeting HER2/neu and MDM2 pathways will allow for a two-pronged attack on breast cancer. The overall objective of our...proposal is to determine if small molecule drugs designed to inhibit HER2/neu can be applied in combination with drugs designed to inhibit p53-MDM2...able to inhibit either the HER2/neu pathway or the p53-MDM2 pathway. Subsequently, designed small molecule drugs able to strongly induce apoptosis

Synergistically killing activity of aspirin and histone deacetylase inhibitor valproic acid (VPA) on hepatocellular cancer cells

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

Li, Xiaofei; Zhu, Yanshuang; He, Huabin

Highlights: •Novel combination therapy using aspirin and valproic acid (VPA). •Combination of aspirin and VPA elicits synergistic cytotoxic effects. •Combination of aspirin and VPA significantly reduces the drug dosage required alone. •Combination of aspirin and VPA significantly inhibit tumor growth. •Lower dose of aspirin in combination therapy will minimize side effects of aspirin. -- Abstract: Aspirin and valproic acid (VPA) have been extensively studied for inducing various malignancies growth inhibition respectively, despite their severe side effects. Here, we developed a novel combination by aspirin and VPA on hepatocellular cancer cells (HCCs). The viability of HCC lines were analyzed by MTTmore » assay, apoptotic analysis of HepG2 and SMMC-7721 cell was performed. Real time-PCR and Western blotting were performed to determine the expression of apoptosis related genes and proteins such as Survivin, Bcl-2/Bax, Cyclin D1 and p15. Moreover, orthotopic xenograft tumors were challenged in nude mice to establish murine model, and then therapeutic effect was analyzed after drug combination therapy. The viability of HCC lines’ significantly decreased after drug combination treatment, and cancer cell apoptosis in combination group increasingly induced compared with single drug use. Therapeutic effect was significantly enhanced by combination therapy in tumor volume and tumor weight decrease. From the data shown here, aspirin and VPA combination have a synergistic killing effect on hepatocellular cancers cells proliferation and apoptosis.« less

Combinatorial therapy discovery using mixed integer linear programming.

PubMed

Pang, Kaifang; Wan, Ying-Wooi; Choi, William T; Donehower, Lawrence A; Sun, Jingchun; Pant, Dhruv; Liu, Zhandong

2014-05-15

Combinatorial therapies play increasingly important roles in combating complex diseases. Owing to the huge cost associated with experimental methods in identifying optimal drug combinations, computational approaches can provide a guide to limit the search space and reduce cost. However, few computational approaches have been developed for this purpose, and thus there is a great need of new algorithms for drug combination prediction. Here we proposed to formulate the optimal combinatorial therapy problem into two complementary mathematical algorithms, Balanced Target Set Cover (BTSC) and Minimum Off-Target Set Cover (MOTSC). Given a disease gene set, BTSC seeks a balanced solution that maximizes the coverage on the disease genes and minimizes the off-target hits at the same time. MOTSC seeks a full coverage on the disease gene set while minimizing the off-target set. Through simulation, both BTSC and MOTSC demonstrated a much faster running time over exhaustive search with the same accuracy. When applied to real disease gene sets, our algorithms not only identified known drug combinations, but also predicted novel drug combinations that are worth further testing. In addition, we developed a web-based tool to allow users to iteratively search for optimal drug combinations given a user-defined gene set. Our tool is freely available for noncommercial use at http://www.drug.liuzlab.org/. zhandong.liu@bcm.edu Supplementary data are available at Bioinformatics online.

Modulating PD-L1 expression in multiple myeloma: an alternative strategy to target the PD-1/PD-L1 pathway.

PubMed

Tremblay-LeMay, Rosemarie; Rastgoo, Nasrin; Chang, Hong

2018-03-27

Even with recent advances in therapy regimen, multiple myeloma patients commonly develop drug resistance and relapse. The relevance of targeting the PD-1/PD-L1 axis has been demonstrated in pre-clinical models. Monotherapy with PD-1 inhibitors produced disappointing results, but combinations with other drugs used in the treatment of multiple myeloma seemed promising, and clinical trials are ongoing. However, there have recently been concerns about the safety of PD-1 and PD-L1 inhibitors combined with immunomodulators in the treatment of multiple myeloma, and several trials have been suspended. There is therefore a need for alternative combinations of drugs or different approaches to target this pathway. Protein expression of PD-L1 on cancer cells, including in multiple myeloma, has been associated with intrinsic aggressive features independent of immune evasion mechanisms, thereby providing a rationale for the adoption of new strategies directly targeting PD-L1 protein expression. Drugs modulating the transcriptional and post-transcriptional regulation of PD-L1 could represent new therapeutic strategies for the treatment of multiple myeloma, help potentiate the action of other drugs or be combined to PD-1/PD-L1 inhibitors in order to avoid the potentially problematic combination with immunomodulators. This review will focus on the pathophysiology of PD-L1 expression in multiple myeloma and drugs that have been shown to modulate this expression.

Statistical Signal Process in R Language in the Pharmacovigilance Programme of India.

PubMed

Kumar, Aman; Ahuja, Jitin; Shrivastava, Tarani Prakash; Kumar, Vipin; Kalaiselvan, Vivekanandan

2018-05-01

The Ministry of Health & Family Welfare, Government of India, initiated the Pharmacovigilance Programme of India (PvPI) in July 2010. The purpose of the PvPI is to collect data on adverse reactions due to medications, analyze it, and use the reference to recommend informed regulatory intervention, besides communicating the risk to health care professionals and the public. The goal of the present study was to apply statistical tools to find the relationship between drugs and ADRs for signal detection by R programming. Four statistical parameters were proposed for quantitative signal detection. These 4 parameters are IC 025 , PRR and PRR lb , chi-square, and N 11 ; we calculated these 4 values using R programming. We analyzed 78,983 drug-ADR combinations, and the total count of drug-ADR combination was 4,20,060. During the calculation of the statistical parameter, we use 3 variables: (1) N 11 (number of counts), (2) N 1. (Drug margin), and (3) N .1 (ADR margin). The structure and calculation of these 4 statistical parameters in R language are easily understandable. On the basis of the IC value (IC value >0), out of the 78,983 drug-ADR combination (drug-ADR combination), we found the 8,667 combinations to be significantly associated. The calculation of statistical parameters in R language is time saving and allows to easily identify new signals in the Indian ICSR (Individual Case Safety Reports) database.

Modeling Tumor Clonal Evolution for Drug Combinations Design

PubMed Central

Zhao, Boyang; Hemann, Michael T.; Lauffenburger, Douglas A.

2016-01-01

Cancer is a clonal evolutionary process. This presents challenges for effective therapeutic intervention, given the constant selective pressure towards drug resistance. Mathematical modeling from population genetics, evolutionary dynamics, and engineering perspectives are being increasingly employed to study tumor progression, intratumoral heterogeneity, drug resistance, and rational drug scheduling and combinations design. In this review, we discuss promising opportunities these inter-disciplinary approaches hold for advances in cancer biology and treatment. We propose that quantitative modeling perspectives can complement emerging experimental technologies to facilitate enhanced understanding of disease progression and improved capabilities for therapeutic drug regimen designs. PMID:28435907

Dandruff, seborrheic dermatitis, and psoriasis drug products containing coal tar and menthol for over-the-counter human use; amendment to the monograph. Final rule

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

NONE

2006-03-15

The Food and Drug Administration (FDA) is issuing a final rule amending the final monograph (FM) for over-the-counter (OTC) dandruff, seborrheic dermatitis, and psoriasis drug products to include the combination of 1.8 percent coal tar solution and 1.5 percent menthol in a shampoo drug product to control dandruff. FDA did not receive any comments or data in response to its previously proposed rule to include this combination. This final rule is part of FDA's ongoing review of OTC drug products.

RNAi-combined nano-chemotherapeutics to tackle resistant tumors.

PubMed

Tekade, Rakesh Kumar; Tekade, Muktika; Kesharwani, Prashant; D'Emanuele, Antony

2016-11-01

The merger of nanotechnology and combination chemotherapy has shown notable promise in the therapy of resistant tumors. The latest scientific attention encompasses the engagement of anticancer drugs in combination with small interfering (si)RNAs, such as VEGF, XLAP, PGP, MRP-1, BCL-2 and cMyc, to name but a few. siRNAs have shown immense promise to knockout drug resistance genes as well as to recover the sensitivity of resistant tumors to anticancer therapy. The nanotechnology approach could also protect siRNA against RNAse degradation as well as prevent off-target effects. In this article, we discuss the approaches that have been used to deliver of siRNA in combination with chemotherapeutic drugs to treat resistant tumors. We also discuss the stipulations that must be considered in formulating a nanotechnology-assisted siRNA-drug cancer therapy. Copyright © 2016. Published by Elsevier Ltd.

The colorimetric analysis of anti-tuberculosis fixed-dose combination tablets and capsules.

PubMed

Ellard, G A

1999-11-01

The perceived need to demonstrate whether or not the actual amounts of rifampicin, isoniazid and pyrazinamide in fixed-dose combination tablets or capsules correspond to their stated drug contents. To adapt specific, robust and simple colorimetric methods that have been previously applied to measuring plasma and urinary rifampicin, isoniazid, pyrazinamide and ethambutol concentrations to estimate tablet and capsule drug contents. The methods were applied to the analysis of 14 commercially manufactured fixed-dose combinations: two capsule and three tablet formulations containing rifampicin and isoniazid; seven tablet formulations containing rifampicin, isoniazid and pyrazinamide; and two tablet formulations containing rifampicin, isoniazid, pyrazinamide and ethambutol. All the combined formulations contained near to their stated drug contents. Replicate analyses confirmed the excellent precision of the drug analyses. Such methods are not only rapid to perform but should be practical in many Third World situations with relatively modest laboratory facilities.

Consensus Recommendations on Sulfonylurea and Sulfonylurea Combinations in the Management of Type 2 Diabetes Mellitus – International Task Force

PubMed Central

Kalra, Sanjay; Bahendeka, Silver; Sahay, Rakesh; Ghosh, Sujoy; Md, Fariduddin; Orabi, Abbas; Ramaiya, Kaushik; Al Shammari, Sameer; Shrestha, Dina; Shaikh, Khalid; Abhayaratna, Sachitha; Shrestha, Pradeep K.; Mahalingam, Aravinthan; Askheta, Mazen; A. Rahim, Aly Ahmed; Eliana, Fatimah; Shrestha, Hari K.; Chaudhary, Sandeep; Ngugi, Nancy; Mbanya, Jean Claude; Aye, Than Than; Latt, Tint Swe; Akanov, Zhanay A.; Syed, Abbas Raza; Tandon, Nikhil; Unnikrishnan, A. G.; Madhu, S. V.; Jawa, Ali; Chowdhury, Subhankar; Bajaj, Sarita; Das, Ashok Kumar

2018-01-01

For decades, sulfonylureas (SUs) have been important drugs in the antidiabetic therapeutic armamentarium. They have been used as monotherapy as well as combination therapy. Focus on newer drugs and concerns about the risk of severe hypoglycemia and weight gain with some SUs have led to discussion on their safety and utility. It has to be borne in mind that the adverse events associated with SUs should not be ascribed to the whole class, as many modern SUs, such as glimepiride and gliclazide modified release, are associated with better safety profiles. Furthermore, individualization of treatment, using SUs in combination with other drugs, backed with careful monitoring and patient education, ensures maximum benefits with minimal side effects. The current guidelines, developed by experts from Africa, Asia, and the Middle East, promote the safe and smart use of SUs in combination with other glucose-lowering drugs. PMID:29535952

Activity of Picolinic Acid in Combination with the Antiprotozoal Drug Quinacrine against Mycobacterium avium Complex

PubMed Central

Shimizu, Toshiaki; Tomioka, Haruaki

2006-01-01

We studied the in vitro and in vivo antimicrobial activities of picolinic acid (PA) in combination with the antiprotozoal drug quinacrine against intramacrophage Mycobacterium avium complex (MAC). Quinacrine significantly potentiated the anti-MAC activity of PA, suggesting the usefulness of this combination in the clinical control of MAC infection. PMID:16940126

Minocycline and N-acetylcysteine: A Synergistic Drug Combination to Treat Traumatic Brain Injury

DTIC Science & Technology

2013-10-01

Contract Number: W81XWH-10-2-0171 TITLE: Minocycline and...30September2012-29September2013 4. TITLE AND SUBTITLE Minocycline and N-acetylcysteine: a synergistic drug combination to treat...grantee previously found screened that the combination of minocycline (MINO) and N-acetyl cysteine (NAC) synergistically improved brain function when

Sample size requirements for separating out the effects of combination treatments: Randomised controlled trials of combination therapy vs. standard treatment compared to factorial designs for patients with tuberculous meningitis

PubMed Central

2011-01-01

Background In certain diseases clinical experts may judge that the intervention with the best prospects is the addition of two treatments to the standard of care. This can either be tested with a simple randomized trial of combination versus standard treatment or with a 2 × 2 factorial design. Methods We compared the two approaches using the design of a new trial in tuberculous meningitis as an example. In that trial the combination of 2 drugs added to standard treatment is assumed to reduce the hazard of death by 30% and the sample size of the combination trial to achieve 80% power is 750 patients. We calculated the power of corresponding factorial designs with one- to sixteen-fold the sample size of the combination trial depending on the contribution of each individual drug to the combination treatment effect and the strength of an interaction between the two. Results In the absence of an interaction, an eight-fold increase in sample size for the factorial design as compared to the combination trial is required to get 80% power to jointly detect effects of both drugs if the contribution of the less potent treatment to the total effect is at least 35%. An eight-fold sample size increase also provides a power of 76% to detect a qualitative interaction at the one-sided 10% significance level if the individual effects of both drugs are equal. Factorial designs with a lower sample size have a high chance to be underpowered, to show significance of only one drug even if both are equally effective, and to miss important interactions. Conclusions Pragmatic combination trials of multiple interventions versus standard therapy are valuable in diseases with a limited patient pool if all interventions test the same treatment concept, it is considered likely that either both or none of the individual interventions are effective, and only moderate drug interactions are suspected. An adequately powered 2 × 2 factorial design to detect effects of individual drugs would require at least 8-fold the sample size of the combination trial. Trial registration Current Controlled Trials ISRCTN61649292 PMID:21288326

In vitro testing of drug combinations employing nilotinib and alkylating agents with regard to pretransplant conditioning treatment of advanced-phase chronic myeloid leukemia.

PubMed

Radujkovic, Aleksandar; Luft, Thomas; Dreger, Peter; Ho, Anthony D; Jens Zeller, W; Fruehauf, Stefan; Topaly, Julian

2014-08-01

The prognosis of patients with advanced-phase chronic myeloid leukemia (CML) remains dismal despite the availability of targeted therapies and allogeneic stem cell transplantation (allo-SCT). Increasing the antileukemic efficacy of the pretransplant conditioning regimen may be a strategy to increase remission rates and duration. We therefore investigated the antiproliferative effects of nilotinib in combination with drugs that are usually used for conditioning: the alkylating agents mafosfamide, treosulfan, and busulfan. Drug combinations were tested in vitro in different imatinib-sensitive and imatinib-resistant BCR-ABL-positive cell lines. A tetrazolium-based MTT assay was used for the assessment and quantification of growth inhibition after exposure to alkylating agents alone or to combinations with nilotinib. Drug interaction was analyzed using the median-effect method of Chou and Talalay, and combination index (CI) values were calculated according to the classic isobologram equation. Treatment of imatinib-sensitive, BCR-ABL-positive K562 and LAMA84 cells with nilotinib in combination with mafosfamide, treosulfan, or busulfan resulted in synergistic (CI < 1), additive (CI ~ 1), and predominantly antagonistic (CI > 1) effects, respectively. In imatinib-resistant K562-R and LAMA84-R cells, all applied drug combinations were synergistic (CI < 1) at higher growth inhibition levels. Our in vitro data warrant further investigation and may provide the basis for nilotinib-supplemented conditioning regimens for allo-SCT in advanced-phase CML.

Drugs Approved for Ovarian, Fallopian Tube, or Primary Peritoneal Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for ovarian cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

Drugs Approved for Multiple Myeloma

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for multiple myeloma and other plasma cell neoplasms. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters. The drug names link to NCI's Cancer Drug Information summaries.

A bioactive implant in situ and long-term releases combined drugs for treatment of osteoarticular tuberculosis.

PubMed

Zhou, Chao-Xi; Li, Litao; Ma, Yi-Guang; Li, Bing-Nan; Li, Guang; Zhou, Zhihang; Shi, Feng; Weng, Jie; Zhang, Cong; Wang, Fenghua; Cui, Xu; Wang, Lei; Wang, Hao

2018-05-24

Anti-tuberculosis chemotherapy with a long duration and adequate dosing is the mainstay for treatment of osteoarticular tuberculosis (TB). However, it is difficult for systemic administration to reach adequate local drug concentrations and achieve effective treatment. Herein, a hydroxyapatite (HA) scaffold implant combined with a drug-releasing system was designed to achieve in situ and long-term anti-TB drug release and highly efficient therapeutic activity in vitro and in vivo. The clinical anti-TB drugs hydrophilic isoniazid (INH) and hydrophobic rifampicin (RFP) were molecularly dispersed into polyvinyl alcohol (PVA) through immersion-curing techniques and were steadily adhered onto the surfaces of HA scaffolds (HA-drug@PVA). The HA-drug@PVA scaffolds showed a long-term, sustained drug release profile and killed proliferating Mycobacteriumin vitro. In vivo experimental results revealed that the HA-drug@PVA scaffolds provided over 10- and 100-fold higher concentrations in muscles and bones, respectively, as well as a much lower concentration (<0.025) in blood. Furthermore, the HA-drug@PVA scaffold implanted in an osteoarticular TB rabbit model showed obvious bone regeneration and fusion due to the inhibition of TB-associated inflammatory changes. The excellent therapeutic effects indicate that in situ implant materials combined with a long-term drug release system are promising for the treatment of osteoarticular TB and other osteoarticular infections. Copyright © 2018. Published by Elsevier Ltd.

Combined treatment of UVA irradiation and antibiotics induces greater bactericidal effects on Vibrio parahaemolyticus.

PubMed

Hou, Yanfei; Nakahashi, Mutsumi; Mawatari, Kazuaki; Shimohata, Takaaki; Uebanso, Takashi; Harada, Yumi; Tsunedomi, Akari; Emoto, Takahiro; Akutagawa, Masatake; Kinouchi, Yohsuke; Takahashi, Akira

2016-01-01

The presence of antibiotics in the environment and their subsequent impact on the development of multi-antibiotic resistant bacteria has raised concerns globally. Consequently, much research is focused on a method to produce a better disinfectant. We have established a disinfectant system using UVA-LED that inactivates pathogenic bacteria. We assessed the bactericidal efficiency of a combination of UVA-LED and antibiotics against Vibrio parahaemolyticus. Combined use of antibiotic drugs and UVA irradiation was more bactericidal than UVA irradiation or antibacterial drugs alone. The bactericidal synergy was observed at low concentrations of each drug that are normally unable to kill the bacteria. This combination has the potential to become a sterilization technology.

Synergistic effects of galantamine and memantine in attenuating scopolamine-induced amnesia in mice.

PubMed

Busquet, Perrine; Capurro, Valeria; Cavalli, Andrea; Piomelli, Daniele; Reggiani, Angelo; Bertorelli, Rosalia

2012-01-01

We investigated a possible drug efficacy enhancement obtained by combining inactive doses of galantamine and memantine in the scopolamine-induced amnesia model in mice. We evaluated the effects of the two drugs, either alone or in combination, using the spontaneous alternation and object recognition tasks. In both tests, combination of low doses of galantamine (0.1 mg/kg, s.c.) and memantine (0.5 mg/kg, i.p.), which were sub-active per se, rescued the memory impairment induced by scopolamine (1 mg/kg, i.p.). The results suggest that combinations of galantamine and memantine might provide a more effective treatment of memory impairments in cognitive disorders than either drug used alone.

Drugs Approved for Pancreatic Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for pancreatic cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

Drugs Approved for Lung Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for lung cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

Drugs Approved for Breast Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for breast cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

Drugs Approved for Bladder Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for bladder cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

β-casein nanovehicles for oral delivery of chemotherapeutic Drug combinations overcoming P-glycoprotein-mediated multidrug resistance in human gastric cancer cells.

PubMed

Bar-Zeev, Maya; Assaraf, Yehuda G; Livney, Yoav D

2016-04-26

Multidrug resistance (MDR) is a primary obstacle to curative cancer therapy. We have previously demonstrated that β-casein (β-CN) micelles (β-CM) can serve as nanovehicles for oral delivery and target-activated release of hydrophobic drugs in the stomach. Herein we introduce a novel nanosystem based on β-CM, to orally deliver a synergistic combination of a chemotherapeutic drug (Paclitaxel) and a P-glycoprotein-specific transport inhibitor (Tariquidar) individually encapsulated within β-CM, for overcoming MDR in gastric cancer. Light microscopy, dynamic light scattering and zeta potential analyses revealed solubilization of these drugs by β-CN, suppressing drug crystallization. Spectrophotometry demonstrated high loading capacity and good encapsulation efficiency, whereas spectrofluorometry revealed high affinity of these drugs to β-CN. In vitro cytotoxicity assays exhibited remarkable synergistic efficacy against human MDR gastric carcinoma cells with P-glycoprotein overexpression. Oral delivery of β-CN - based nanovehicles carrying synergistic drug combinations to the stomach constitutes a novel efficacious therapeutic system that may overcome MDR in gastric cancer.

Panitumumab-Conjugated Pt-Drug Nanomedicine for Enhanced Efficacy of Combination Targeted Chemotherapy against Colorectal Cancer.

PubMed

Tsai, Ming-Hsien; Pan, Chao-Hsuan; Peng, Cheng-Liang; Shieh, Ming-Jium

2017-07-01

Targeted combination chemotherapy (TCT) has recently been used to increase the induction of tumor cell death. In particular, the combination of Panitumumab and the platinum (Pt)-derived chemotherapeutic drug Oxaliplatin is clinically effective against KRAS and BRAF wild-type colorectal cancer (CRC) cells that overexpress epidermal growth factor receptors, and significantly greater efficacy is observed than with either drug alone. However, low accumulation of Pt drug in tumor sites prevents achievement of ideal efficacy. To develop an alternative drug therapy that achieves the ideal efficacy of TCT, the novel nanomedicine NANO Pt-Pan using self-assembled dichloro(1,2-diaminocyclohexane)Pt(II)-modified Panitumumab is generated. Treatments with NANO Pt-Pan lead to significant accumulation of Pt drug and Panitumumab in tumors, reflecting enhanced permeability and retention effect, active targeting, and sustained circulation of the Pt drug in the blood. In addition, NANO Pt-Pan has excellent in vivo anti-CRC efficacy. These data indicate that NANO Pt-Pan has high potential as a candidate nanomedicine for CRC. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Promotion of the transdermal delivery of protein drugs by N-trimethyl chitosan nanoparticles combined with polypropylene electret.

PubMed

Tu, Ye; Wang, Xinxia; Lu, Ying; Zhang, He; Yu, Yuan; Chen, Yan; Liu, Junjie; Sun, Zhiguo; Cui, Lili; Gao, Jing; Zhong, Yanqiang

We recently reported that electret, which was prepared by a corona charging system with polypropylene film, could enhance the transdermal delivery of several drugs of low molecular weight. The aim of this study was to investigate whether electret could enhance the transdermal delivery of protein drugs by N -trimethyl chitosan nanoparticles (TMC NPs) prepared by an ionic gelation method. A series of experiments were performed, including in vitro skin permeation assays and anti-inflammatory effects, to evaluate the transdermal delivery of protein drugs by TMC NPs in the presence of electret. The results showed that in the presence of electret, the transdermal delivery of protein drugs in TMC NPs was significantly enhanced, as demonstrated by in vitro permeation studies and confocal laser scanning microscopy. Notably, superoxide dismutase-loaded TMC NPs combined with electret exhibited the best inhibitory effect on the edema of the mouse ear. TMC NPs combined with electret represent a novel platform for the transdermal delivery of protein drugs.

Promotion of the transdermal delivery of protein drugs by N-trimethyl chitosan nanoparticles combined with polypropylene electret

PubMed Central

Tu, Ye; Wang, Xinxia; Lu, Ying; Zhang, He; Yu, Yuan; Chen, Yan; Liu, Junjie; Sun, Zhiguo; Cui, Lili; Gao, Jing; Zhong, Yanqiang

2016-01-01

We recently reported that electret, which was prepared by a corona charging system with polypropylene film, could enhance the transdermal delivery of several drugs of low molecular weight. The aim of this study was to investigate whether electret could enhance the transdermal delivery of protein drugs by N-trimethyl chitosan nanoparticles (TMC NPs) prepared by an ionic gelation method. A series of experiments were performed, including in vitro skin permeation assays and anti-inflammatory effects, to evaluate the transdermal delivery of protein drugs by TMC NPs in the presence of electret. The results showed that in the presence of electret, the transdermal delivery of protein drugs in TMC NPs was significantly enhanced, as demonstrated by in vitro permeation studies and confocal laser scanning microscopy. Notably, superoxide dismutase-loaded TMC NPs combined with electret exhibited the best inhibitory effect on the edema of the mouse ear. TMC NPs combined with electret represent a novel platform for the transdermal delivery of protein drugs. PMID:27822034

Drugs in the Pipeline for the Obesity Market

PubMed Central

Klonoff, David C.; Greenway, Frank

2008-01-01

Obesity is a major public health problem. For many obese patients, diet and exercise are an inadequate treatment and bariatric surgery may be too extreme of a treatment. As with many other chronic diseases, pharmacologic treatment may be an attractive option for selected obese patients. Antiobesity drugs may potentially work through one of three mechanisms: (1) appetite suppression, (2) interference with absorption of nutrients, and (3) increased metabolism of nutrients. The three most widely prescribed drugs approved to treat obesity are phentermine, sibutramine, and orlistat. Drugs approved for treating obesity usually result in an additional weight loss of approximately 2–5 kg in addition to placebo. For pharmacologic therapy in obesity to be widely utilized, greater effectiveness and safety will be needed. Four types of single-agent drugs are in late stage development, including (1) selective central cannabinoid-1 receptor blockers, (2) selective central 5-hydroxytryptamine 2C serotonin receptor agonists, (3) an intestinal lipase blocker, and (4) central-acting incretin mimetic drugs. Four combination agent compounds in late stage development include (1) Contrave, which combines long-acting versions of naltrexone and bupropion; (2) Empatic, which combines long-acting bupropion and long-acting zonisamide; (3) Qnexa, which combines phentermine with controlled release topiramate; and (4) an injectable combination of leptin and pramlintide. Peptide YY and melanin-concentrating hormone receptor-1 antagonists are centrally acting agents in early stage development. It is expected that several new drug products for obesity will become available over the next few years. Their role in managing this disease remains to be determined. PMID:19885278

Study on the Increased Probability of Detecting Adverse Drug Reactions Based on Bayes' Theorem: Evaluation of the Usefulness of Information on the Onset Timing of Adverse Drug Reactions.

PubMed

Oshima, Shinji; Enjuji, Takako; Negishi, Akio; Akimoto, Hayato; Ohara, Kousuke; Okita, Mitsuyoshi; Numajiri, Sachihiko; Inoue, Naoko; Ohshima, Shigeru; Terao, Akira; Kobayashi, Daisuke

2017-09-01

In order to avoid adverse drug reactions (ADRs), pharmacists are reconstructing ADR-related information based on various types of data gathered from patients, and then providing this information to patients. Among the data provided to patients is the time-to-onset of ADRs after starting the medication (i.e., ADR onset timing information). However, a quantitative evaluation of the effect of onset timing information offered by pharmacists on the probability of ADRs occurring in patients receiving this information has not been reported to date. In this study, we extracted 40 ADR-drug combinations from the data in the Japanese Adverse Drug Event Report database. By applying Bayes' theorem to these combinations, we quantitatively evaluated the usefulness of onset timing information as an ADR detection predictor. As a result, when information on days after taking medication was added, 54 ADR-drug combinations showed a likelihood ratio (LR) in excess of 2. In particular, when considering the ADR-drug combination of anaphylactic shock with levofloxacin or loxoprofen, the number of days elapsed between start of medication and the onset of the ADR was 0, which corresponded to increased likelihood ratios (LRs) of 138.7301 or 58.4516, respectively. When information from 1-7 d after starting medication was added to the combination of liver disorder and acetaminophen, the LR was 11.1775. The results of this study indicate the clinical usefulness of offering information on ADR onset timing.

Drugs in the pipeline for the obesity market.

PubMed

Klonoff, David C; Greenway, Frank

2008-09-01

Obesity is a major public health problem. For many obese patients, diet and exercise are an inadequate treatment and bariatric surgery may be too extreme of a treatment. As with many other chronic diseases, pharmacologic treatment may be an attractive option for selected obese patients. Antiobesity drugs may potentially work through one of three mechanisms: (1) appetite suppression, (2) interference with absorption of nutrients, and (3) increased metabolism of nutrients. The three most widely prescribed drugs approved to treat obesity are phentermine, sibutramine, and orlistat. Drugs approved for treating obesity usually result in an additional weight loss of approximately 2-5 kg in addition to placebo. For pharmacologic therapy in obesity to be widely utilized, greater effectiveness and safety will be needed. Four types of single-agent drugs are in late stage development, including (1) selective central cannabinoid-1 receptor blockers, (2) selective central 5-hydroxytryptamine 2C serotonin receptor agonists, (3) an intestinal lipase blocker, and (4) central-acting incretin mimetic drugs. Four combination agent compounds in late stage development include (1) Contrave, which combines long-acting versions of naltrexone and bupropion; (2) Empatic, which combines long-acting bupropion and long-acting zonisamide; (3) Qnexa, which combines phentermine with controlled release topiramate; and (4) an injectable combination of leptin and pramlintide. Peptide YY and melanin-concentrating hormone receptor-1 antagonists are centrally acting agents in early stage development. It is expected that several new drug products for obesity will become available over the next few years. Their role in managing this disease remains to be determined.

Predictive modeling of structured electronic health records for adverse drug event detection.

PubMed

Zhao, Jing; Henriksson, Aron; Asker, Lars; Boström, Henrik

2015-01-01

The digitization of healthcare data, resulting from the increasingly widespread adoption of electronic health records, has greatly facilitated its analysis by computational methods and thereby enabled large-scale secondary use thereof. This can be exploited to support public health activities such as pharmacovigilance, wherein the safety of drugs is monitored to inform regulatory decisions about sustained use. To that end, electronic health records have emerged as a potentially valuable data source, providing access to longitudinal observations of patient treatment and drug use. A nascent line of research concerns predictive modeling of healthcare data for the automatic detection of adverse drug events, which presents its own set of challenges: it is not yet clear how to represent the heterogeneous data types in a manner conducive to learning high-performing machine learning models. Datasets from an electronic health record database are used for learning predictive models with the purpose of detecting adverse drug events. The use and representation of two data types, as well as their combination, are studied: clinical codes, describing prescribed drugs and assigned diagnoses, and measurements. Feature selection is conducted on the various types of data to reduce dimensionality and sparsity, while allowing for an in-depth feature analysis of the usefulness of each data type and representation. Within each data type, combining multiple representations yields better predictive performance compared to using any single representation. The use of clinical codes for adverse drug event detection significantly outperforms the use of measurements; however, there is no significant difference over datasets between using only clinical codes and their combination with measurements. For certain adverse drug events, the combination does, however, outperform using only clinical codes. Feature selection leads to increased predictive performance for both data types, in isolation and combined. We have demonstrated how machine learning can be applied to electronic health records for the purpose of detecting adverse drug events and proposed solutions to some of the challenges this presents, including how to represent the various data types. Overall, clinical codes are more useful than measurements and, in specific cases, it is beneficial to combine the two.

Predictive modeling of structured electronic health records for adverse drug event detection

PubMed Central

2015-01-01

Background The digitization of healthcare data, resulting from the increasingly widespread adoption of electronic health records, has greatly facilitated its analysis by computational methods and thereby enabled large-scale secondary use thereof. This can be exploited to support public health activities such as pharmacovigilance, wherein the safety of drugs is monitored to inform regulatory decisions about sustained use. To that end, electronic health records have emerged as a potentially valuable data source, providing access to longitudinal observations of patient treatment and drug use. A nascent line of research concerns predictive modeling of healthcare data for the automatic detection of adverse drug events, which presents its own set of challenges: it is not yet clear how to represent the heterogeneous data types in a manner conducive to learning high-performing machine learning models. Methods Datasets from an electronic health record database are used for learning predictive models with the purpose of detecting adverse drug events. The use and representation of two data types, as well as their combination, are studied: clinical codes, describing prescribed drugs and assigned diagnoses, and measurements. Feature selection is conducted on the various types of data to reduce dimensionality and sparsity, while allowing for an in-depth feature analysis of the usefulness of each data type and representation. Results Within each data type, combining multiple representations yields better predictive performance compared to using any single representation. The use of clinical codes for adverse drug event detection significantly outperforms the use of measurements; however, there is no significant difference over datasets between using only clinical codes and their combination with measurements. For certain adverse drug events, the combination does, however, outperform using only clinical codes. Feature selection leads to increased predictive performance for both data types, in isolation and combined. Conclusions We have demonstrated how machine learning can be applied to electronic health records for the purpose of detecting adverse drug events and proposed solutions to some of the challenges this presents, including how to represent the various data types. Overall, clinical codes are more useful than measurements and, in specific cases, it is beneficial to combine the two. PMID:26606038

Pharmacokinetics and Drug Interactions Determine Optimum Combination Strategies in Computational Models of Cancer Evolution.

PubMed

Chakrabarti, Shaon; Michor, Franziska

2017-07-15

The identification of optimal drug administration schedules to battle the emergence of resistance is a major challenge in cancer research. The existence of a multitude of resistance mechanisms necessitates administering drugs in combination, significantly complicating the endeavor of predicting the evolutionary dynamics of cancers and optimal intervention strategies. A thorough understanding of the important determinants of cancer evolution under combination therapies is therefore crucial for correctly predicting treatment outcomes. Here we developed the first computational strategy to explore pharmacokinetic and drug interaction effects in evolutionary models of cancer progression, a crucial step towards making clinically relevant predictions. We found that incorporating these phenomena into our multiscale stochastic modeling framework significantly changes the optimum drug administration schedules identified, often predicting nonintuitive strategies for combination therapies. We applied our approach to an ongoing phase Ib clinical trial (TATTON) administering AZD9291 and selumetinib to EGFR-mutant lung cancer patients. Our results suggest that the schedules used in the three trial arms have almost identical efficacies, but slight modifications in the dosing frequencies of the two drugs can significantly increase tumor cell eradication. Interestingly, we also predict that drug concentrations lower than the MTD are as efficacious, suggesting that lowering the total amount of drug administered could lower toxicities while not compromising on the effectiveness of the drugs. Our approach highlights the fact that quantitative knowledge of pharmacokinetic, drug interaction, and evolutionary processes is essential for identifying best intervention strategies. Our method is applicable to diverse cancer and treatment types and allows for a rational design of clinical trials. Cancer Res; 77(14); 3908-21. ©2017 AACR . ©2017 American Association for Cancer Research.

Pharmacokinetic interaction of enrofloxacin/trimethoprim combination following single-dose intraperitoneal and oral administration in rats.

PubMed

Choi, Myung-Jin; Yohannes, Sileshi Belew; Lee, Seung-Jin; Damte, Dereje; Kim, Jong-Choon; Suh, Joo-Won; Park, Seung-Chun

2014-03-01

The pharmacokinetic interaction of enrofloxacin and trimethoprim was evaluated after single-dose intraperitoneal or oral co-administration in rats. Plasma concentrations of the two drugs were determined by high-performance liquid chromatography. Following intraperitoneal combination, a significant (P < 0.05) increase in mean values of plasma half-life (t 1/2) and maximum plasma concentration (C max) was observed for enrofloxacin and trimethoprim, respectively. There was a significant (P < 0.05) increase in mean values of area under the plasma drug concentration versus time from time zero to infinity (AUC0-∞) and C max between combined oral doses (10, 30 and 100 mg/kg) of both antibacterial drugs. Also, after oral conjugation a significant difference in mean values of MRT0-∞ was observed between lower (10 mg/kg) and higher (100 mg/kg) doses of both drugs. A significant increase in pharmacokinetic parameters of both drugs in combined intraperitoneal and oral doses indicated pharmacokinetic interaction of enrofloxacin and trimethoprim. Further study is recommended in other species of animals.

Drugs given by a syringe driver: a prospective multicentre survey of palliative care services in the UK.

PubMed

Wilcock, Andrew; Jacob, Jayin K; Charlesworth, Sarah; Harris, Elayne; Gibbs, Margaret; Allsop, Helen

2006-10-01

The use of a syringe driver to administer drugs by continuous subcutaneous infusion is common practice in the UK. Over time, drug combinations used in a syringe driver are likely to change and the aim of this survey was to obtain a more recent snapshot of practice. On four separate days, at two-week intervals, a questionnaire was completed for every syringe driver in use by 15 palliative care services. Of 336 syringe drivers, the majority contained either two or three drugs, but one-fifth contained only one drug. The median (range) volume of the infusions was 15 (9.5-48) mL, and duration of infusion was generally 24 hours. Only one combination was reported as visually incompatible, and there were 13 site reactions (4% of total). Laboratory physical and chemical compatibility data are available for less than half of the most frequently used combinations.

A combinatorial screen of the CLOUD uncovers a synergy targeting the androgen receptor.

PubMed

Licciardello, Marco P; Ringler, Anna; Markt, Patrick; Klepsch, Freya; Lardeau, Charles-Hugues; Sdelci, Sara; Schirghuber, Erika; Müller, André C; Caldera, Michael; Wagner, Anja; Herzog, Rebecca; Penz, Thomas; Schuster, Michael; Boidol, Bernd; Dürnberger, Gerhard; Folkvaljon, Yasin; Stattin, Pär; Ivanov, Vladimir; Colinge, Jacques; Bock, Christoph; Kratochwill, Klaus; Menche, Jörg; Bennett, Keiryn L; Kubicek, Stefan

2017-07-01

Approved drugs are invaluable tools to study biochemical pathways, and further characterization of these compounds may lead to repurposing of single drugs or combinations. Here we describe a collection of 308 small molecules representing the diversity of structures and molecular targets of all FDA-approved chemical entities. The CeMM Library of Unique Drugs (CLOUD) covers prodrugs and active forms at pharmacologically relevant concentrations and is ideally suited for combinatorial studies. We screened pairwise combinations of CLOUD drugs for impairment of cancer cell viability and discovered a synergistic interaction between flutamide and phenprocoumon (PPC). The combination of these drugs modulates the stability of the androgen receptor (AR) and resensitizes AR-mutant prostate cancer cells to flutamide. Mechanistically, we show that the AR is a substrate for γ-carboxylation, a post-translational modification inhibited by PPC. Collectively, our data suggest that PPC could be repurposed to tackle resistance to antiandrogens in prostate cancer patients.

Acquired resistance to combination treatment through loss of synergy with MEK and PI3K inhibitors in colorectal cancer

PubMed Central

Bhattacharya, Bhaskar; Low, Sarah Hong Hui; Chong, Mei Ling; Chia, Dilys; Koh, King Xin; Sapari, Nur Sabrina; Kaye, Stanley; Hung, Huynh; Benoukraf, Touati; Soong, Richie

2016-01-01

Historically, understanding of acquired resistance (AQR) to combination treatment has been based on knowledge of resistance to its component agents. To test whether an altered drug interaction could be an additional factor in AQR to combination treatment, models of AQR to combination and single agent MEK and PI3K inhibitor treatment were generated. Combination indices indicated combination treatment of PI3K and MEK inhibitors remained synergistic in cells with AQR to single agent but not combination AQR cells. Differences were also observed between the models in cellular phenotypes, pathway signaling and drug cross-resistance. Genomics implicated TGFB2-EDN1 overexpression as candidate determinants in models of AQR to combination treatment. Supplementation of endothelin in parental cells converted synergism to antagonism. Silencing of TGFB2 or EDN1 in cells with AQR conferred synergy between PI3K and MEK inhibitor. These results highlight that AQR to combination treatment may develop through alternative mechanisms to those of single agent treatment, including a change in drug interaction. PMID:27081080

Combination of injectable ethinyl estradiol and drospirenone drug-delivery systems and characterization of their in vitro release.

PubMed

Nippe, Stefanie; General, Sascha

2012-11-20

Our aim was to investigate the in vitro release and combination of ethinyl estradiol (EE) and drospirenone (DRSP) drug-delivery systems. DRSP poly(lactic-co-glycolic acid) (PLGA) microparticles and organogels containing DRSP microcrystals were prepared and characterized with regard to properties influencing drug release. The morphology and release kinetics of DRSP PLGA microparticles indicated that DRSP is dispersed in the polymer. The in vitro release profiles correlated well with in vivo data. Although DRSP degradation is known to be acid-catalyzed, DRSP was relatively stable in the PLGA matrix. Aqueous DRSP PLGA microparticle suspensions were combinable with EE PLGA microparticles and EE poly(butylcyanoacrylate) (PBCA) microcapsules without interacting. EE release from PLGA microparticles was faster than DRSP release; EE release is assumed to be primarily controlled by drug diffusion. Liquid-filled EE PBCA microcapsules were shown to be more robust than air-filled EE PBCA microcapsules; the bursting of microcapsules accelerating the drug delivery was therefore delayed. The drug release profile for DRSP organogels was fairly linear with the square root of time. The system was not combinable with EE PBCA microcapsules. In contrast, incorporation of EE PLGA microparticles in organogels resulted in prolonged EE release. The drug release of EE and DRSP was thus approximated. Copyright © 2012 Elsevier B.V. All rights reserved.

Patient-derived models of acquired resistance can identify effective drug combinations for cancer.

PubMed

Crystal, Adam S; Shaw, Alice T; Sequist, Lecia V; Friboulet, Luc; Niederst, Matthew J; Lockerman, Elizabeth L; Frias, Rosa L; Gainor, Justin F; Amzallag, Arnaud; Greninger, Patricia; Lee, Dana; Kalsy, Anuj; Gomez-Caraballo, Maria; Elamine, Leila; Howe, Emily; Hur, Wooyoung; Lifshits, Eugene; Robinson, Hayley E; Katayama, Ryohei; Faber, Anthony C; Awad, Mark M; Ramaswamy, Sridhar; Mino-Kenudson, Mari; Iafrate, A John; Benes, Cyril H; Engelman, Jeffrey A

2014-12-19

Targeted cancer therapies have produced substantial clinical responses, but most tumors develop resistance to these drugs. Here, we describe a pharmacogenomic platform that facilitates rapid discovery of drug combinations that can overcome resistance. We established cell culture models derived from biopsy samples of lung cancer patients whose disease had progressed while on treatment with epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors and then subjected these cells to genetic analyses and a pharmacological screen. Multiple effective drug combinations were identified. For example, the combination of ALK and MAPK kinase (MEK) inhibitors was active in an ALK-positive resistant tumor that had developed a MAP2K1 activating mutation, and the combination of EGFR and fibroblast growth factor receptor (FGFR) inhibitors was active in an EGFR mutant resistant cancer with a mutation in FGFR3. Combined ALK and SRC (pp60c-src) inhibition was effective in several ALK-driven patient-derived models, a result not predicted by genetic analysis alone. With further refinements, this strategy could help direct therapeutic choices for individual patients. Copyright © 2014, American Association for the Advancement of Science.

Synergistic apoptosis in head and neck squamous cell carcinoma cells by co-inhibition of insulin-like growth factor-1 receptor signaling and compensatory signaling pathways.

PubMed

Axelrod, Mark J; Mendez, Rolando E; Khalil, Ashraf; Leimgruber, Stephanie S; Sharlow, Elizabeth R; Capaldo, Brian; Conaway, Mark; Gioeli, Daniel G; Weber, Michael J; Jameson, Mark J

2015-12-01

In head and neck squamous cell carcinoma (HNSCC), resistance to single-agent targeted therapy may be overcome by co-targeting of compensatory signaling pathways. A targeted drug screen with 120 combinations was used on 9 HNSCC cell lines. Multiple novel drug combinations demonstrated synergistic growth inhibition. Combining the insulin-like growth factor-1 receptor (IGF-1R) inhibitor, BMS754807, with either the human epidermal growth factor receptor (HER)-family inhibitor, BMS599626, or the Src-family kinase inhibitor, dasatinib, resulted in substantial synergy and growth inhibition. Depending on the cell line, these combinations induced synergistic or additive apoptosis; when synergistic apoptosis was observed, AKT phosphorylation was inhibited to a greater extent than either drug alone. Conversely, when additive apoptosis occurred, AKT phosphorylation was not reduced by the drug combination. Combined IGF-1R/HER family and IGF-1R/Src family inhibition may have therapeutic potential in HNSCC. AKT may be a node of convergence between IGF-1R signaling and pathways that compensate for IGF-1R inhibition. © 2015 Wiley Periodicals, Inc.

The combination of aricept with a traditional Chinese medicine formula, smart soup, may be a novel way to treat Alzheimer's disease.

PubMed

Wang, Ying; Wang, Ying; Sui, Yi; Yu, Hongshuang; Shen, Xiaoheng; Chen, Shengdi; Pei, Gang; Zhao, Jian; Ding, Jianqing

2015-01-01

Alzheimer's disease (AD) is a common neurodegenerative disease affecting cognitive function in the elderly, which is characterized by the presence of extracellular deposits of insoluble amyloid-β plaques and neuronal loss. Modern pharmacology and drug development usually follow a single-target principle, which might contribute to the failure of most compounds in clinical trials against AD. Considering AD is a multifactorial disease, a combination therapeutic strategy that applies drugs with different mechanisms would be an alternative way. Smart Soup (SS), a Traditional Chinese Medicine formula, is composed of three herbaceous plants and has been applied in the treatment of amnesia in China for hundreds of years. In this work, we studied the clinical potency of the combination of SS and Aricept in AD therapy. In the in vivo model, both longevity and locomotive activity of AD transgenic Drosophila were improved remarkably in the combined medicine treated group. We also observed less amyloid-β deposition and retarded neuronal loss following the combined drug treatment. In the retrospective cohort study, we found the combination therapy exerted better therapeutic effect on AD patients. Our study revealed that combination therapy with multiple drug targets did have a better therapeutic outcome. It provides a new strategy to develop an optimum pharmaceutical approach against AD.

Differences in combinations and concentrations of drugs of abuse in fatal intoxication and driving under the influence cases.

PubMed

Edvardsen, Hilde Erøy; Tverborgvik, Torill; Frost, Joachim; Rogde, Sidsel; Morild, Inge; Waal, Helge; Clausen, Thomas; Slørdal, Lars; Vindenes, Vigdis

2017-12-01

In toxicology, international classification systems focus on single intoxicants as the cause of death. It is, however, well known that very few drug related deaths are caused by a single substance and that information concerning the drug concentrations as well as the combinations of drugs are essential in order to ascertain the cause of death. The aim of the study was to assess whether those prone to fatal intoxications differ significantly from chronic drug users - in terms of demographics and drug exposure patterns. Fatal psychoactive drug intoxications in Norway during 2012, where a forensic autopsy including toxicological analysis were performed, were included. Analytical findings in blood were compared with concentrations in blood from apprehended drivers under the influence of drugs and ethanol (DUID) during the same time period. The opioid and benzodiazepine concentrations were assessed as morphine and diazepam equivalents, respectively, in order to compare concentrations across the different groups. A total of 194 autopsy cases and 4811 DUID cases were included. Opioids were detected in around 90% of the drug intoxication cases, but in only 16% of the DUID cases. The number of substances detected in fatal intoxications was 4.9 compared to 2.6 in the DUID cases. The total opioid concentrations were significantly higher in the fatal intoxication cases compared to DUID cases (229ng/mL versus 56.9ng/mL morphine equivalents, respectively). Benzodiazepines were detected in 90% of the fatal cases. Only one fatal opioid mono-intoxication was found; a case with a very high methadone concentration (1238ng/mL). Mono-intoxication with heroin was not seen in any of the fatal intoxications in Norway, and single drug intoxications were rare (1.5%). Fatal intoxications were caused by a combination of drugs with significantly more substances as well as higher total drug concentrations among the fatal cases compared to the DUID cases. The combination of opioids and benzodiazepines seemed to represent an increased risk of death. The total load of drugs influence the degree of intoxication and the total concentration level must be considered, including the total number of substances. Our findings imply that international statistics regarding an opioid being the main intoxicant should have a shift in focus towards combinations of drugs (especially opioids and benzodiazepines) as a major risk factor for fatal drug overdoses. Copyright © 2017 Elsevier B.V. All rights reserved.

Revisiting Dosing Regimen Using Pharmacokinetic/Pharmacodynamic Mathematical Modeling: Densification and Intensification of Combination Cancer Therapy.

PubMed

Meille, Christophe; Barbolosi, Dominique; Ciccolini, Joseph; Freyer, Gilles; Iliadis, Athanassios

2016-08-01

Controlling effects of drugs administered in combination is particularly challenging with a densified regimen because of life-threatening hematological toxicities. We have developed a mathematical model to optimize drug dosing regimens and to redesign the dose intensification-dose escalation process, using densified cycles of combined anticancer drugs. A generic mathematical model was developed to describe the main components of the real process, including pharmacokinetics, safety and efficacy pharmacodynamics, and non-hematological toxicity risk. This model allowed for computing the distribution of the total drug amount of each drug in combination, for each escalation dose level, in order to minimize the average tumor mass for each cycle. This was achieved while complying with absolute neutrophil count clinical constraints and without exceeding a fixed risk of non-hematological dose-limiting toxicity. The innovative part of this work was the development of densifying and intensifying designs in a unified procedure. This model enabled us to determine the appropriate regimen in a pilot phase I/II study in metastatic breast patients for a 2-week-cycle treatment of docetaxel plus epirubicin doublet, and to propose a new dose-ranging process. In addition to the present application, this method can be further used to achieve optimization of any combination therapy, thus improving the efficacy versus toxicity balance of such a regimen.

Sulforaphane Increases Drug-mediated Cytotoxicity Toward Cancer Stem-like Cells of Pancreas and Prostate

PubMed Central

Kallifatidis, Georgios; Labsch, Sabrina; Rausch, Vanessa; Mattern, Juergen; Gladkich, Jury; Moldenhauer, Gerhard; Büchler, Markus W.; Salnikov, Alexei V.; Herr, Ingrid

2011-01-01

Despite intense efforts to develop treatments against pancreatic cancer, agents that cure this highly resistant and metastasizing disease are not available. Considerable attention has focused on broccoli compound sulforaphane (SF), which is suggested as combination therapy for targeting of pancreatic cancer stem cells (CSCs). However, there are concerns that antioxidative properties of SF may interfere with cytotoxic drugs—as suggested, e.g., for vitamins. Therefore we investigated a combination therapy using established pancreatic CSCs. Although cisplatin (CIS), gemcitabine (GEM), doxorubicin, 5-flurouracil, or SF effectively induced apoptosis and prevented viability, combination of a drug with SF increased toxicity. Similarly, SF potentiated the drug effect in established prostate CSCs revealing that SF enhances drug cytotoxicity also in other tumor entities. Most importantly, combined treatment intensified inhibition of clonogenicity and spheroid formation and aldehyde dehydrogenase 1 (ALDH1) activity along with Notch-1 and c-Rel expression indicating that CSC characteristics are targeted. In vivo, combination treatment was most effective and totally abolished growth of CSC xenografts and tumor-initiating potential. No pronounced side effects were observed in normal cells or mice. Our data suggest that SF increases the effectiveness of various cytotoxic drugs against CSCs without inducing additional toxicity in mice. PMID:20940707

Thermodynamics of Highly Supersaturated Aqueous Solutions of Poorly Water-Soluble Drugs-Impact of a Second Drug on the Solution Phase Behavior and Implications for Combination Products.

PubMed

Trasi, Niraj S; Taylor, Lynne S

2015-08-01

There is increasing interest in formulating combination products that contain two or more drugs. Furthermore, it is also common for different drug products to be taken simultaneously. This raises the possibility of interactions between different drugs that may impact formulation performance. For poorly water-soluble compounds, the supersaturation behavior may be a critical factor in determining the extent of oral absorption. The goal of the current study was to evaluate the maximum achievable supersaturation for several poorly water-soluble compounds alone, and in combination. Model compounds included ritonavir, lopinavir, paclitaxel, felodipine, and diclofenac. The "amorphous solubility" for the pure drugs was determined using different techniques and the change in this solubility was then measured in the presence of differing amounts of a second drug. The results showed that "amorphous solubility" of each component in aqueous solution is substantially decreased by the second component, as long as the two drugs are miscible in the amorphous state. A simple thermodynamic model could be used to predict the changes in solubility as a function of composition. This information is of great value when developing co-amorphous or other supersaturating formulations and should contribute to a broader understanding of drug-drug physicochemical interactions in in vitro assays as well as in the gastrointestinal tract. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

The role of the time-kill kinetics assay as part of a preclinical modeling framework for assessing the activity of anti-tuberculosis drugs.

PubMed

Bax, Hannelore I; Bakker-Woudenberg, Irma A J M; de Vogel, Corné P; van der Meijden, Aart; Verbon, Annelies; de Steenwinkel, Jurriaan E M

2017-07-01

Novel treatment strategies for tuberculosis are urgently needed. Many different preclinical models assessing anti-tuberculosis drug activity are available, but it is yet unclear which combination of models is most predictive of clinical treatment efficacy. The aim of this study was to determine the role of our in vitro time kill-kinetics assay as an asset to a predictive preclinical modeling framework assessing anti-tuberculosis drug activity. The concentration- and time-dependent mycobacterial killing capacities of six anti-tuberculosis drugs were determined during exposure as single drugs or in dual, triple and quadruple combinations towards a Mycobacterium tuberculosis Beijing genotype strain and drug resistance was assessed. Streptomycin, rifampicin and isoniazid were most active against fast-growing M. tuberculosis. Isoniazid with rifampicin or high dose ethambutol were the only synergistic drug combinations. The addition of rifampicin or streptomycin to isoniazid prevented isoniazid resistance. In vitro ranking showed agreement with early bactericidal activity in tuberculosis patients for some but not all anti-tuberculosis drugs. The time-kill kinetics assay provides important information on the mycobacterial killing dynamics of anti-tuberculosis drugs during the early phase of drug exposure. As such, this assay is a valuable component of the preclinical modeling framework. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visible light-induced crosslinking and physiological stabilization of diselenide-rich nanoparticles for redox-responsive drug release and combination chemotherapy.

PubMed

Zhai, Shaodong; Hu, Xianglong; Hu, Yongjun; Wu, Baoyan; Xing, Da

2017-03-01

Undesired physiological instability of nanocarriers and premature drug leakage during blood circulation result in compromised therapeutic efficacy and severe side effects, which have significantly impeded the development of nanomedicine. Facile crosslinking of drug-loaded nanocarriers while keeping the potency of site-specific degradation and drug release has emerged as a viable strategy to overcome these drawbacks. Additionally, combination therapy has already shown advantages in inhibiting advanced tumors and life extension than single drug therapy. Herein, three kinds of diselenide-rich polymers were fabricated with distinct hydrophobic side chains. The component effect was interrogated to screen out PEG-b-PBSe diblock copolymer due to its favorable self-assembly controllability and high drug loading of camptothecin (CPT) and doxorubicin (DOX) that had synergistic antitumor property. Facile visible light-induced diselenide metathesis and regeneration was employed to crosslink nanocarriers for the first time. The dual drug-loaded crosslinked micelles (CPT/DOX-CCM) were stable in physiological conditions with minimal drug leakage, possessing extended blood circulation, whereas hand-in-hand dual drug release was significantly accelerated in tumor's redox microenvironments. In vitro cytotoxicity evaluation and in vivo tumor suppression with low dosage drugs further demonstrated the favorable potency of the redox-responsive nanoplatform in tumor combination chemotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Medicalized addiction, self-medication, or nonmedical prescription drug use? How trust figures into incarcerated women's conceptualization of illicit prescription drug use.

PubMed

Smirnova, Michelle; Owens, Jennifer Gatewood

2017-06-01

Trust is crucial to optimal care. When trust is compromised, patients, doctors, and others involved in the provision of health care may not act in patients' best interests, particularly when dealing with prescription (Rx) drugs. Patients must trust that doctors are giving them the proper treatment, including access to Rx drugs only when medically necessary. They must also trust themselves to use these drugs properly. Likewise, doctors must trust the patient's ability to use medications appropriately. Given the recent rise in illicit Rx drug use in the U.S., we seek to understand how women articulate levels of trust in doctors and themselves and if different combinations of trust and distrust impact how they acquire, use, and articulate their experiences with Rx drugs. To this end, we identified and interviewed 40 women incarcerated in the U.S., who were deeply entrenched in illicit Rx drug use prior to prison. Based upon this research, we argue that illicit Rx drug use may be tied to different combinations of trust and distrust in individual doctors (interpersonal trust), the field of medicine (institutional trust), and the users themselves (self trust). How these women acquire Rx drugs: through doctors, friends, family, or the street market are influenced by combinations of interpersonal, institutional, and self trust. Copyright © 2017 Elsevier Ltd. All rights reserved.

Induction of Early Autophagic Process on Leishmania amazonensis by Synergistic Effect of Miltefosine and Innovative Semi-synthetic Thiosemicarbazone

PubMed Central

Scariot, Débora B.; Britta, Elizandra A.; Moreira, Amanda L.; Falzirolli, Hugo; Silva, Cleuza C.; Ueda-Nakamura, Tânia; Dias-Filho, Benedito P.; Nakamura, Celso V.

2017-01-01

Drug combination therapy is a current trend to treat complex diseases. Many benefits are expected from this strategy, such as cytotoxicity decrease, retardation of resistant strains development, and activity increment. This study evaluated in vitro combination between an innovative thiosemicarbazone molecule – BZTS with miltefosine, a drug already consolidated in the leishmaniasis treatment, against Leishmania amazonensis. Cytotoxicity effects were also evaluated on macrophages and erythrocytes. Synergistic antileishmania effect and antagonist cytotoxicity were revealed from this combination therapy. Mechanisms of action assays were performed in order to investigate the main cell pathways induced by this treatment. Mitochondrial dysfunction generated a significant increase of reactive oxygen and nitrogen species production, causing severe cell injuries and promoting intense autophagy process and consequent apoptosis cell death. However, this phenomenon was not strong enough to promote dead in mammalian cell, providing the potential selective effect of the tested combination for the protozoa. Thus, the results confirmed that drugs involved in distinct metabolic routes are promising agents for drug combination therapy, promoting a synergistic effect. PMID:28270805

Modeling antibiotic treatment in hospitals: A systematic approach shows benefits of combination therapy over cycling, mixing, and mono-drug therapies.

PubMed

Tepekule, Burcu; Uecker, Hildegard; Derungs, Isabel; Frenoy, Antoine; Bonhoeffer, Sebastian

2017-09-01

Multiple treatment strategies are available for empiric antibiotic therapy in hospitals, but neither clinical studies nor theoretical investigations have yielded a clear picture when which strategy is optimal and why. Extending earlier work of others and us, we present a mathematical model capturing treatment strategies using two drugs, i.e the multi-drug therapies referred to as cycling, mixing, and combination therapy, as well as monotherapy with either drug. We randomly sample a large parameter space to determine the conditions determining success or failure of these strategies. We find that combination therapy tends to outperform the other treatment strategies. By using linear discriminant analysis and particle swarm optimization, we find that the most important parameters determining success or failure of combination therapy relative to the other treatment strategies are the de novo rate of emergence of double resistance in patients infected with sensitive bacteria and the fitness costs associated with double resistance. The rate at which double resistance is imported into the hospital via patients admitted from the outside community has little influence, as all treatment strategies are affected equally. The parameter sets for which combination therapy fails tend to fall into areas with low biological plausibility as they are characterised by very high rates of de novo emergence of resistance to both drugs compared to a single drug, and the cost of double resistance is considerably smaller than the sum of the costs of single resistance.

[Clinical trial of a combination of three drugs in fixed proportions in the treatment of tuberculosis. Groupe de Travail sur la Chimiothérapie de la Tuberculose].

PubMed

Chaulet, P; Boulahbal, F

1995-10-01

The Matiben Chest Clinic at the West Algiers University Teaching Hospital, and 3 outpatient clinics specializing in tuberculosis and lung disease in Algiers. To determine the tolerance and efficacy of a fixed proportion combination of 3 antituberculosis drugs (per tablet: 50 mg isoniazid + 120 mg rifampicin + 300 mg pyrazinamide) given during the first 2 months of a daily 6-month chemotherapy regimen. Random prospective treatment trial comparing a group of 124 patients receiving the triple combination with another group of 126 patients receiving the 3 drugs separately during the initial treatment phase. The continuation phase was identical for the 2 groups. Comparison of tolerance in the first 2 months, and of the failure and relapse rates (respectively at the end of treatment and 24 months after the end of treatment). During the first 2 months side-effects were significantly more common in the group receiving the drugs separately. At the end of treatment and during the following 24 months there were no significant differences in the cumulative rates of observed failures and relapses (2% and 1%). The triple combination studied could replace the separate drugs in the initial treatment phase in countries where the bioavailability of the drugs used has been proven.

Mirincamycin, an old candidate for malaria combination treatment and prophylaxis in the 21st century: in vitro interaction profiles with potential partner drugs in continuous culture and field isolates.

PubMed

Starzengruber, Peter; Fuehrer, Hans-Peter; Swoboda, Paul; Ganesh, Deepa; Haque, Rashidul; Khan, Wasif A; Graninger, Wolfgang; Noedl, Harald

2014-06-10

Spreading resistance of Plasmodium falciparum to existing drugs calls for the search for novel anti-malarial drugs and combinations for the treatment of falciparum malaria. In vitro and ex vivo investigations were conducted with fresh P. falciparum field isolates and culture-adapted P. falciparum clones to evaluate the anti-malarial potential of mirincamycin, a lincosamide, alone and in combination with tafenoquine (TQ), dihydroartemisinin (DHA), and chloroquine (CQ). All samples were tested in a histidine-rich protein 2 (HRP2) drug susceptibility assay. Interaction analysis showed additive to synergistic interaction profiles with these potential partner drugs, with an overall geometric mean fractional inhibitory concentration at 50% inhibition (FIC₅₀) of 0.78, 0.80 and 0.80 for mirincamycin with TQ, DHA, and CQ, respectively. Antagonism was not found in any of the tested field isolates or clones. The strongest tendency toward synergy (i.e. the lowest FIC) was seen with a combination ratio of 1:0.27 to 1:7.2 (mean 1:2.7) for the combination with tafenoquine. The optimal combination ratios for DHA and CQ were 1:444.4 to 1:36,000 (mean 1:10,755.5) and 1:2.7 to 1:216 (mean 1:64.5), respectively. No evidence of an activity correlation (i.e. potential cross-resistance) with DHA, mefloquine, quinine or chloroquine was seen whereas a significant correlation with the activity of clindamycin and azithromycin was detected. Mirincamycin combinations may be promising candidates for further clinical investigations in the therapy and prophylaxis of multidrug-resistant falciparum malaria or in combination with 4 or 8-aminoquinolines for the treatment and relapse prevention of vivax malaria.

Mirincamycin, an old candidate for malaria combination treatment and prophylaxis in the 21st century: in vitro interaction profiles with potential partner drugs in continuous culture and field isolates

PubMed Central

2014-01-01

Background Spreading resistance of Plasmodium falciparum to existing drugs calls for the search for novel anti-malarial drugs and combinations for the treatment of falciparum malaria. Methods In vitro and ex vivo investigations were conducted with fresh P. falciparum field isolates and culture-adapted P. falciparum clones to evaluate the anti-malarial potential of mirincamycin, a lincosamide, alone and in combination with tafenoquine (TQ), dihydroartemisinin (DHA), and chloroquine (CQ). All samples were tested in a histidine-rich protein 2 (HRP2) drug susceptibility assay. Results Interaction analysis showed additive to synergistic interaction profiles with these potential partner drugs, with an overall geometric mean fractional inhibitory concentration at 50% inhibition (FIC50) of 0.78, 0.80 and 0.80 for mirincamycin with TQ, DHA, and CQ, respectively. Antagonism was not found in any of the tested field isolates or clones. The strongest tendency toward synergy (i.e. the lowest FIC) was seen with a combination ratio of 1:0.27 to 1:7.2 (mean 1:2.7) for the combination with tafenoquine. The optimal combination ratios for DHA and CQ were 1:444.4 to 1:36,000 (mean 1:10,755.5) and 1:2.7 to 1:216 (mean 1:64.5), respectively. No evidence of an activity correlation (i.e. potential cross-resistance) with DHA, mefloquine, quinine or chloroquine was seen whereas a significant correlation with the activity of clindamycin and azithromycin was detected. Conclusions Mirincamycin combinations may be promising candidates for further clinical investigations in the therapy and prophylaxis of multidrug-resistant falciparum malaria or in combination with 4 or 8-aminoquinolines for the treatment and relapse prevention of vivax malaria. PMID:24916383

Quantitative model for the blood pressure-lowering interaction of valsartan and amlodipine.

PubMed

Heo, Young-A; Holford, Nick; Kim, Yukyung; Son, Mijeong; Park, Kyungsoo

2016-12-01

The objective of this study was to develop a population pharmacokinetic (PK) and pharmacodynamic (PD) model to quantitatively describe the antihypertensive effect of combined therapy with amlodipine and valsartan. PK modelling was used with data collected from 48 healthy volunteers receiving a single dose of combined formulation of 10 mg amlodipine and 160 mg valsartan. Systolic (SBP) and diastolic blood pressure (DBP) were recorded during combined administration. SBP and DBP data for each drug alone were gathered from the literature. PKPD models of each drug and for combined administration were built with NONMEM 7.3. A two-compartment model with zero order absorption best described the PK data of both drugs. Amlodipine and valsartan monotherapy effects on SBP and DBP were best described by an I max model with an effect compartment delay. Combined therapy was described using a proportional interaction term as follows: (D 1  + D 2 ) +ALPHA×(D 1 × D 2 ). D 1 and D 2 are the predicted drug effects of amlodipine and valsartan monotherapy respectively. ALPHA is the interaction term for combined therapy. Quantitative estimates of ALPHA were -0.171 (95% CI: -0.218, -0.143) for SBP and -0.0312 (95% CI: -0.07739, -0.00283) for DBP. These infra-additive interaction terms for both SBP and DBP were consistent with literature results for combined administration of drugs in these classes. PKPD models for SBP and DBP successfully described the time course of the antihypertensive effects of amlodipine and valsartan. An infra-additive interaction between amlodipine and valsartan when used in combined administration was confirmed and quantified. © 2016 The British Pharmacological Society.

Quantitative model for the blood pressure‐lowering interaction of valsartan and amlodipine

PubMed Central

Heo, Young‐A; Holford, Nick; Kim, Yukyung; Son, Mijeong

2016-01-01

Aims The objective of this study was to develop a population pharmacokinetic (PK) and pharmacodynamic (PD) model to quantitatively describe the antihypertensive effect of combined therapy with amlodipine and valsartan. Methods PK modelling was used with data collected from 48 healthy volunteers receiving a single dose of combined formulation of 10 mg amlodipine and 160 mg valsartan. Systolic (SBP) and diastolic blood pressure (DBP) were recorded during combined administration. SBP and DBP data for each drug alone were gathered from the literature. PKPD models of each drug and for combined administration were built with NONMEM 7.3. Results A two‐compartment model with zero order absorption best described the PK data of both drugs. Amlodipine and valsartan monotherapy effects on SBP and DBP were best described by an I max model with an effect compartment delay. Combined therapy was described using a proportional interaction term as follows: (D1 + D2) +ALPHA×(D1 × D2). D1 and D2 are the predicted drug effects of amlodipine and valsartan monotherapy respectively. ALPHA is the interaction term for combined therapy. Quantitative estimates of ALPHA were −0.171 (95% CI: −0.218, −0.143) for SBP and −0.0312 (95% CI: −0.07739, −0.00283) for DBP. These infra‐additive interaction terms for both SBP and DBP were consistent with literature results for combined administration of drugs in these classes. Conclusion PKPD models for SBP and DBP successfully described the time course of the antihypertensive effects of amlodipine and valsartan. An infra‐additive interaction between amlodipine and valsartan when used in combined administration was confirmed and quantified. PMID:27504853

Development of a new delivery system consisting in 'drug-in cyclodextrin-in PLGA nanoparticles'.

PubMed

Mura, Paola; Maestrelli, Francesca; Cecchi, Matteo; Bragagni, Marco; Almeida, Antonio

2010-01-01

A combined approach based on drug cyclodextrin (CD) complexation and loading into PLGA nanoparticles (NP) has been developed to improve oxaprozin therapeutic efficiency. This strategy exploits the solubilizing and stabilizing properties of CDs and the prolonged-release and targeting properties of PLGA NPs. Drug-loaded NPs, prepared by double-emulsion, were examined for dimensions, zeta-potential and entrapment efficiency. Solid-state studies demonstrated the absence of drug-polymer interactions and assessed the amorphous state of the drug-CD complex loaded into NPs. Drug release rate from NPs was strongly influenced by the presence and kind of CD used. The percentage released at 24 h varied from 16% (plain drug-loaded NPs) to 50% (drug-betaCD-loaded NPs) up to 100% (drug-methylbetaCD-loaded NPs). This result suggests the possibility of using CD complexation not only to promote, but also to regulate drug release rate from NPs, by selecting the proper type of CD or CD combination.

Microfluidic Remote Loading for Rapid Single-Step Liposomal Drug Preparation

PubMed Central

Hood, R.R.; Vreeland, W. N.; DeVoe, D.L.

2014-01-01

Microfluidic-directed formation of liposomes is combined with in-line sample purification and remote drug loading for single step, continuous-flow synthesis of nanoscale vesicles containing high concentrations of stably loaded drug compounds. Using an on-chip microdialysis element, the system enables rapid formation of large transmembrane pH and ion gradients, followed by immediate introduction of amphipathic drug for real-time remote loading into the liposomes. The microfluidic process enables in-line formation of drug-laden liposomes with drug:lipid molar ratios of up to 1.3, and a total on-chip residence time of approximately 3 min, representing a significant improvement over conventional bulk-scale methods which require hours to days for combined liposome synthesis and remote drug loading. The microfluidic platform may be further optimized to support real-time generation of purified liposomal drug formulations with high concentrations of drugs and minimal reagent waste for effective liposomal drug preparation at or near the point of care. PMID:25003823

Drugs Approved for Colon and Rectal Cancer

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for use in colon cancer and rectal cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

Synergistic Antiproliferative Effects of a New Cucurbitacin B Derivative and Chemotherapy Drugs on Lung Cancer Cell Line A549.

PubMed

Marostica, Lucas Lourenço; Silva, Izabella Thaís; Kratz, Jadel Müller; Persich, Lara; Geller, Fabiana Cristina; Lang, Karen Luise; Caro, Miguel Soriano Balparda; Durán, Fernando Javier; Schenkel, Eloir Paulo; Simões, Cláudia Maria Oliveira

2015-10-19

Nonsmall cell lung cancer (NSCLC) represents an important cause of mortality worldwide due to its aggressiveness and growing resistance to currently available therapy. Cucurbitacins have emerged as novel potential anticancer agents showing strong antiproliferative effects and can be promising candidates for combined treatments with clinically used anticancer agents. This study investigates the synergistic antiproliferative effects of a new semisynthetic derivative of cucurbitacin B (DACE) with three chemotherapy drugs: cisplatin (CIS), irinotecan (IRI), and paclitaxel (PAC) on A549 cells. The most effective combinations were selected for studies of the mechanism of action. Using an in silico tool, DACE seems to act by a different mechanism of action when compared with that of different classes of drugs already used in clinical settings. DACE also showed potent synergic effects with drugs, and the most potent combinations induced G2/M cell cycle arrest by modulating survivin and p53 expression, disruption of F-actin cytoskeleton, and cell death by apoptosis. These treatments completely inhibited the clonogenic potential and did not reduce the proliferation of nontumoral lung cells (MRC-5). DACE also showed relevant antimigratory and anti-invasive effects, and combined treatments modulated cell migration signaling pathways evolved with metastasis progression. The effects of DACE associated with drugs was potentiated by the oxidant agent l-buthionine-sulfoximine (BSO), and attenuated by N-acetilcysteine (NAC), an antioxidant agent. The antiproliferative effects induced by combined treatments were attenuated by a pan-caspase inhibitor, indicating that the effects of these treatments are dependent on caspase activity. Our data highlight the therapeutic potential of DACE used in combination with known chemotherapy drugs and offer important insights for the development of more effective and selective therapies against lung cancer.

Clinical trial studies a new form of vincristine in standard combination chemotherapy for children with relapsed ALL | Center for Cancer Research

Cancer.gov

A combination of chemotherapy drugs known by the regimen UK ALL R3 is one of the most successful treatments for patients with relapsed acute lymphoblastic leukemia (ALL). In this study, investigators hope to improve outcomes by combining the treatment with Marqibo, a new formulation of the drug vincristine. Learn more...

Effects of Amphetamine-CNS Depressant Combinations and of Other CNS Stimulants in Four-Choice Drug Discriminations

ERIC Educational Resources Information Center

Li, Mi; Wessinger, William D.; McMillan, D. E.

2005-01-01

Three pigeons were trained to discriminate among 5 mg/kg pentobarbital, 2 mg/kg amphetamine, a combination of these two drugs at these doses, and saline using a four-choice procedure (amphetamine--pentobarbital group). Three other pigeons were trained to discriminate among 5 mg/kg morphine, 2 mg/kg methamphetamine, a combination of these two drugs…

Minocycline and N-acetylcysteine: A Synergistic Drug Combination to Treat Traumatic Brain Injury

DTIC Science & Technology

2011-10-01

AD_________________ Award Number: W81XWH-10-2-0171 TITLE: Minocycline and N-acetylcysteine: A... Minocycline and N-acetylcysteine: A Synergistic Drug Combination to Treat Traumatic Brain Injury 5b. GRANT NUMBER W81XWH-10-2-0171 5c. PROGRAM...combination of minocycline (MINO) and N-acetyl cysteine (NAC) synergistically improved brain function when dosed one hour following closed cortical

Hazards and Benefits of Drug Interaction

ERIC Educational Resources Information Center

Labianca, Dominick A.

1978-01-01

Most cases of drug toxicity are direct consequences of drug misuse--either intentional or inadvertent. Discusses two types of drug interaction--synergistic and antagonistic. The former produces a combined effect greater than the sum of the effects of the individual drugs concerned; the latter is produced when the desired action of one drug is…

Separate and Combined Effects of Naltrexone and Extended-Release Alprazolam on the Reinforcing, Subject-Rated, and Cardiovascular Effects of Methamphetamine

PubMed Central

Marks, Katherine R.; Lile, Joshua A.; Stoops, William W.; Glaser, Paul E.A.; Hays, Lon R.; Rush, Craig R.

2016-01-01

Opioid antagonists (e.g., naltrexone) and positive modulators of γ-aminobutyric acid type A (GABAA) receptors (e.g., alprazolam) each modestly attenuate the abuse-related effects of stimulants. A previous study demonstrated that acute pretreatment with the combination of naltrexone and alprazolam attenuated a greater number of the subject-rated effects of d-amphetamine than the constituent drugs alone. This study tested the hypothesis that maintenance on the combination of naltrexone and alprazolam XR would attenuate the reinforcing and “positive” subject-rated effects of methamphetamine to a greater extent than the constituent drugs alone. Eight non-treatment-seeking, stimulant-using individuals completed a placebo-controlled, crossover, double-blind inpatient protocol. Participants were maintained on naltrexone (0 and 50 mg), alprazolam XR (0 and 1 mg), and the combination of naltrexone and alprazolam XR (50 mg and 1 mg, respectively) for 6–7 days. Under each maintenance condition, participants sampled intranasal doses of methamphetamine (0, 10, and 30 mg), and were then offered the opportunity to work for the sampled dose on a modified progressive-ratio procedure. Subject-rated drug effect questionnaires, psychomotor, and physiology assessments were collected. Intranasal methamphetamine functioned as a reinforcer and produced prototypical stimulant-like “positive” subject-rated and physiological effects. Maintenance on naltrexone significantly decreased the reinforcing, but not subject-rated drug effects of 10 mg methamphetamine. Alprazolam XR and the combination of naltrexone and alprazolam XR did not impact methamphetamine self-administration or subject-rated drug effects. The results support the continued evaluation of naltrexone for methamphetamine dependence, as well as the identification of other drugs that enhance its ability to reduce drug-taking behavior. PMID:27043121

Separate and Combined Effects of Naltrexone and Extended-Release Alprazolam on the Reinforcing, Subject-Rated, and Cardiovascular Effects of Methamphetamine.

PubMed

Marks, Katherine R; Lile, Joshua A; Stoops, William W; Glaser, Paul E A; Hays, Lon R; Rush, Craig R

2016-06-01

Opioid antagonists (eg, naltrexone) and positive modulators of γ-aminobutyric acid type A receptors (eg, alprazolam) each modestly attenuate the abuse-related effects of stimulants. A previous study demonstrated that acute pretreatment with the combination of naltrexone and alprazolam attenuated a greater number of the subject-rated effects of D-amphetamine than the constituent drugs alone. This study tested the hypothesis that maintenance on the combination of naltrexone and alprazolam XR would attenuate the reinforcing and "positive" subject-rated effects of methamphetamine to a greater extent than the constituent drugs alone.Eight non-treatment-seeking, stimulant-using individuals completed a placebo-controlled, crossover, double-blind inpatient protocol. Participants were maintained on naltrexone (0 and 50 mg), alprazolam XR (0 and 1 mg), and the combination of naltrexone and alprazolam XR (50 mg and 1 mg, respectively) for 6 to 7 days. Under each maintenance condition, participants sampled intranasal doses of methamphetamine (0, 10, and 30 mg), and were then offered the opportunity to work for the sampled dose on a modified progressive-ratio procedure. Subject-rated drug effect questionnaires, psychomotor, and physiology assessments were collected.Intranasal methamphetamine functioned as a reinforcer and produced prototypical stimulant-like "positive" subject-rated and physiological effects. Maintenance on naltrexone significantly decreased the reinforcing, but not subject-rated drug effects of 10-mg methamphetamine. Alprazolam XR and the combination of naltrexone and alprazolam XR did not impact methamphetamine self-administration or subject-rated drug effects. The results support the continued evaluation of naltrexone for methamphetamine dependence, as well as the identification of other drugs that enhance its ability to reduce drug-taking behavior.

The Synergistic Effect of Raloxifene, Fluoxetine, and Bromocriptine Protects Against Pilocarpine-Induced Status Epilepticus and Temporal Lobe Epilepsy.

PubMed

Pottoo, Faheem Hyder; Tabassum, Nahida; Javed, Md Noushad; Nigar, Shah; Rasheed, Rouqia; Khan, Ayash; Barkat, Md Abul; Alam, Md Sabir; Maqbool, Amir; Ansari, Mohammad Azam; Barreto, George E; Ashraf, Ghulam Md

2018-06-07

The present antiepileptic drugs pose several problems in the management of seizures owing to their meager neuroprotective potential, adverse effects on bone, detrimental effects on cognitive function, chronic toxicity, drug interactions, side effects including aggression, agitation, and irritability and sometimes exacerbation of seizures. We followed up progressive preclinical investigation in mice against pilocarpine (PILO)-induced status epilepticus (SE) and temporal lobe epilepsy (TLE). To determine the response of raloxifene (RF) (4 and 8 mg/kg), fluoxetine (FT) (14 and 22 mg/kg), bromocriptine (BC) (6 and 10 mg/kg), and their low-dose combinations, oral treatment was scheduled for 28 days followed by PILO (300 mg/kg, i.p). The response was stalked for intensive behavioral monitoring of convulsions, hippocampal neuropeptide Y (NPY), and oxidative stress discernment along with histomorphological studies. The resultant data confirmed the therapeutic potential of triple drug combination of raloxifene (4 mg/kg) with fluoxetine (14 mg/kg) and bromocriptine (6 mg/kg) compared to monotherapy with raloxifene (4 mg/kg), and bromocriptine (6 mg/kg) as otherwise monotherapy with fluoxetine (14 mg/kg) was ineffective to suppress convulsions; an effect better than sodium valproate (300 mg/kg), a standard AED, was validated. Most profoundly, PILO-induced compensatory increases in hippocampal NPY levels (20.01%), which was escalated (100%) with the triple drug combination. The same pattern of results was superseded for oxidative stress indices and neuronal damage. The results for the first time demonstrate the propitious role of triple drug combination in the management of SE and TLE. Therapeutically, this enhancing profile of drugs fosters a safer and more effective drug-combination regimen. Graphical abstract ᅟ.

Sex-dependent long-term effects of adolescent exposure to THC and/or MDMA on neuroinflammation and serotoninergic and cannabinoid systems in rats.

PubMed

Lopez-Rodriguez, Ana Belen; Llorente-Berzal, Alvaro; Garcia-Segura, Luis M; Viveros, Maria-Paz

2014-03-01

Many young people consume ecstasy as a recreational drug and often in combination with cannabis. In this study, we aimed to mimic human consumption patterns and investigated, in male and female animals, the long-term effects of Δ(9) -tetrahydrocannabinol (THC) and 3,4-methylenedioxymethamphetamine (MDMA) on diverse neuroinflammation and neurotoxic markers. Male and female Wistar rats were chronically treated with increasing doses of THC and/or MDMA during adolescence. The effects of THC and/or MDMA on glial reactivity and on serotoninergic and cannabinoid systems were assessed by immunohistochemistry in the hippocampus and parietal cortex. THC increased the area staining for glial fibrilar acidic protein in both sexes. In males, both drugs, either separately or in combination, increased the proportion of reactive microglia cells [ionized calcium binding adaptor molecule 1 (Iba-1)]. In contrast, in females, each drug, administered alone, decreased of this proportion, whereas the combination of both drugs resulted in a 'normalization' to control values. In males, MDMA reduced the number of SERT positive fibres, THC induced the opposite effect and the group receiving both drugs did not significantly differ from the controls. In females, MDMA reduced the number of SERT positive fibres and the combination of both drugs counteracted this effect. THC also reduced immunostaining for CB1 receptors in females and this effect was aggravated by the combination with MDMA. Adolescent exposure of rats to THC and/or MDMA induced long-term, sex-dependent neurochemical and glial alterations, and revealed interactions between the two drugs. This article is part of a themed section on Cannabinoids 2013. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-6. © 2013 The British Pharmacological Society.

Single drug biomarker prediction for ER- breast cancer outcome from chemotherapy.

PubMed

Chen, Yong-Zi; Kim, Youngchul; Soliman, Hatem H; Ying, GuoGuang; Lee, Jae K

2018-06-01

ER-negative breast cancer includes most aggressive subtypes of breast cancer such as triple negative (TN) breast cancer. Excluded from hormonal and targeted therapies effectively used for other subtypes of breast cancer, standard chemotherapy is one of the primary treatment options for these patients. However, as ER- patients have shown highly heterogeneous responses to different chemotherapies, it has been difficult to select most beneficial chemotherapy treatments for them. In this study, we have simultaneously developed single drug biomarker models for four standard chemotherapy agents: paclitaxel (T), 5-fluorouracil (F), doxorubicin (A) and cyclophosphamide (C) to predict responses and survival of ER- breast cancer patients treated with combination chemotherapies. We then flexibly combined these individual drug biomarkers for predicting patient outcomes of two independent cohorts of ER- breast cancer patients who were treated with different drug combinations of neoadjuvant chemotherapy. These individual and combined drug biomarker models significantly predicted chemotherapy response for 197 ER- patients in the Hatzis cohort (AUC = 0.637, P  = 0.002) and 69 ER- patients in the Hess cohort (AUC = 0.635, P  = 0.056). The prediction was also significant for the TN subgroup of both cohorts (AUC = 0.60, 0.72, P  = 0.043, 0.009). In survival analysis, our predicted responder patients showed significantly improved survival with a >17 months longer median PFS than the predicted non-responder patients for both ER- and TN subgroups (log-rank test P -value = 0.018 and 0.044). This flexible prediction capability based on single drug biomarkers may allow us to even select new drug combinations most beneficial to individual patients with ER- breast cancer. © 2018 The authors.

Co-Prescription of QT-Interval Prolonging Drugs: An Analysis in a Large Cohort of Geriatric Patients.

PubMed

Schächtele, Simone; Tümena, Thomas; Gaßmann, Karl-Günter; Fromm, Martin F; Maas, Renke

2016-01-01

Drug-induced QT-interval prolongation is associated with occurrence of potentially fatal Torsades de Pointes arrhythmias (TdP). So far, data regarding the overall burden of QT-interval prolonging drugs (QT-drugs) in geriatric patients are limited. This study was performed to assess the individual burden of QT-interval prolonging drugs (QT-drugs) in geriatric polymedicated patients and to identify the most frequent and risky combinations of QT-drugs. In the discharge medication of geriatric patients between July 2009 and June 2013 from the Geriatrics in Bavaria-Database (GiB-DAT) (co)-prescriptions of QT-drugs were investigated. QT-drugs were classified according to a publicly available reference site (CredibleMeds®) as ALL-QT-drugs (associated with any QT-risk) or High-risk-QT-drugs (corresponding to QT-drugs with known risk of Torsades de Pointes according to CredibleMeds®) and in addition as SmPC-high-risk-QT-drugs (according to the German prescribing information (SmPC) contraindicated co-prescription with other QT-drugs). Of a cohort of 130,434 geriatric patients (mean age 81 years, 67% women), prescribed a median of 8 drugs, 76,594 patients (58.7%) received at least one ALL-QT-drug. Co-prescriptions of two or more ALL-QT-drugs were observed in 28,768 (22.1%) patients. Particularly risky co-prescriptions of High-risk-QT-drugs or SmPC-high-risk-QT-drugs with at least on further QT-drug occurred in 55.9% (N = 12,633) and 54.2% (N = 12,429) of these patients, respectively. Consideration of SmPCs (SmPC-high-risk-QT-drugs) allowed the identification of an additional 15% (N = 3,999) patients taking a risky combination that was not covered by the commonly used CredibleMeds® classification. Only 20 drug-drug combinations accounted for more than 90% of these potentially most dangerous co-prescriptions. In a geriatric study population co-prescriptions of two and more QT-drugs were common. A considerable proportion of QT-drugs with higher risk only could be detected by using more than one classification-system. Local adaption of international classifications can improve identification of patients at risk.

Nanodrug delivery in reversing multidrug resistance in cancer cells

PubMed Central

Kapse-Mistry, Sonali; Govender, Thirumala; Srivastava, Rohit; Yergeri, Mayur

2014-01-01

Different mechanisms in cancer cells become resistant to one or more chemotherapeutics is known as multidrug resistance (MDR) which hinders chemotherapy efficacy. Potential factors for MDR includes enhanced drug detoxification, decreased drug uptake, increased intracellular nucleophiles levels, enhanced repair of drug induced DNA damage, overexpression of drug transporter such as P-glycoprotein(P-gp), multidrug resistance-associated proteins (MRP1, MRP2), and breast cancer resistance protein (BCRP). Currently nanoassemblies such as polymeric/solid lipid/inorganic/metal nanoparticles, quantum dots, dendrimers, liposomes, micelles has emerged as an innovative, effective, and promising platforms for treatment of drug resistant cancer cells. Nanocarriers have potential to improve drug therapeutic index, ability for multifunctionality, divert ABC-transporter mediated drug efflux mechanism and selective targeting to tumor cells, cancer stem cells, tumor initiating cells, or cancer microenvironment. Selective nanocarrier targeting to tumor overcomes dose-limiting side effects, lack of selectivity, tissue toxicity, limited drug access to tumor tissues, high drug doses, and emergence of multiple drug resistance with conventional or combination chemotherapy. Current review highlights various nanodrug delivery systems to overcome mechanism of MDR by neutralizing, evading, or exploiting the drug efflux pumps and those independent of drug efflux pump mechanism by silencing Bcl-2 and HIF1α gene expressions by siRNA and miRNA, modulating ceramide levels and targeting NF-κB. “Theragnostics” combining a cytotoxic agent, targeting moiety, chemosensitizing agent, and diagnostic imaging aid are highlighted as effective and innovative systems for tumor localization and overcoming MDR. Physical approaches such as combination of drug with thermal/ultrasound/photodynamic therapies to overcome MDR are focused. The review focuses on newer drug delivery systems developed to overcome MDR in cancer cell. PMID:25071577

A non-rewarding, non-aversive buprenorphine/naltrexone combination attenuates drug-primed reinstatement to cocaine and morphine in rats in a conditioned place preference paradigm.

PubMed

Cordery, Sarah F; Taverner, Alistair; Ridzwan, Irna E; Guy, Richard H; Delgado-Charro, M Begoña; Husbands, Stephen M; Bailey, Christopher P

2014-07-01

Concurrent use of cocaine and heroin is a major public health issue with no effective relapse prevention treatment currently available. To this purpose, a combination of buprenorphine and naltrexone, a mixed very-low efficacy mu-opioid receptor agonist/kappa-opioid receptor antagonist/nociceptin receptor agonist, was investigated. The tail-withdrawal and the conditioned place preference (CPP) assays in adult Sprague Dawley rats were used to show that naltrexone dose-dependently blocked the mu-opioid receptor agonism of buprenorphine. Furthermore, in the CPP assay, a combination of 0.3 mg/kg buprenorphine and 3.0 mg/kg naltrexone was aversive. A combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone was neither rewarding nor aversive, but still possessed mu-opioid receptor antagonist properties. In the CPP extinction and reinstatement method, a combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone completely blocked drug-primed reinstatement in cocaine-conditioned rats (conditioned with 3 mg/kg cocaine, drug prime was 3 mg/kg cocaine) and attenuated drug-primed reinstatement in morphine-conditioned rats (conditioned with 5 mg/kg morphine, drug prime was 1.25 mg/kg morphine). These data add to the growing evidence that a buprenorphine/naltrexone combination may be protective against relapse in a polydrug abuse situation. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

Synergistic interaction between fentanyl and bupivacaine given intrathecally for labor analgesia.

PubMed

Ngan Kee, Warwick D; Khaw, Kim S; Ng, Floria F; Ng, Karman K L; So, Rita; Lee, Anna

2014-05-01

Lipophilic opioids and local anesthetics are often given intrathecally in combination for labor analgesia. However, the nature of the pharmacologic interaction between these drugs has not been clearly elucidated in humans. Three hundred nulliparous women randomly received 1 of 30 different combinations of fentanyl and bupivacaine intrathecally using a combined spinal-epidural technique for analgesia in the first stage of labor. Visual analogue scale pain scores were recorded for 30 min. Response was defined by percentage decrease in pain score from baseline at 15 and 30 min. Dose-response curves for individual drugs were fitted to a hyperbolic dose-response model using nonlinear regression. The nature of the drug interaction was determined using dose equivalence methodology to compare observed effects of drug combinations with effects predicted by additivity. The derived dose-response models for individual drugs (doses in micrograms) at 15 min were: Effect = 100 × dose / (13.82 + dose) for fentanyl, and Effect = 100 × dose / (1,590 + dose) for bupivacaine. Combinations of fentanyl and bupivacaine produced greater effects than those predicted by additivity at 15 min (P < 0.001) and 30 min (P = 0.015) (mean differences, 9.1 [95% CI, 4.1-14.1] and 6.4 [95% CI, 1.2-11.5] units of the normalized response, respectively), indicating a synergistic interaction. The pharmacologic interaction between intrathecal fentanyl and bupivacaine is synergistic. Characterization and quantification of this interaction provide a theoretical basis and support for the clinical practice of combining intrathecal opioids and local anesthetics.

Drugs Used for Parenteral Sedation in Dental Practice

PubMed Central

Dionne, Raymond A.; Gift, Helen C.

1988-01-01

The relative efficacy and safety of drugs and combinations used clinically in dentistry as premedicants to alleviate patient apprehension are largely unsubstantiated. To evaluate the efficacy and safety of agents used for parenteral sedation through controlled clinical trials, it is first necessary to identify which drugs, doses, and routes of administration are actually used in practice. A survey instrument was developed to characterize the drugs used clinically for anesthesia and sedation by dentists with advanced training in pain control. A random sample of 500 dentists who frequently use anesthesia and sedation in practice was selected from the Fellows of the American Dental Society of Anesthesiology. The first mailing was followed by a second mailing to nonrespondents after 30 days. The respondents report a variety of parenteral sedation techniques in combination with local anesthesia (the response categories are not mutually exclusive): nitrous oxide (64%), intravenous conscious sedation (59%), intravenous “deep” sedation (47%), and outpatient general anesthesia (27%). Drugs most commonly reported for intravenous sedation include diazepam, methohexital, midazolam, and combinations of these drugs with narcotics. A total of 82 distinct drugs and combinations was reported for intravenous sedation and anesthesia. Oral premedication and intramuscular sedation are rarely used by this group. Most general anesthesia reported is done on an outpatient basis in private practice. These results indicate that a wide variety of drugs is employed for parenteral sedation in dental practice, but the most common practice among dentists with advanced training in anesthesia is local anesthesia supplemented with intravenous sedation consisting of a benzodiazepine and an opioid or a barbiturate. PMID:3250279

Regulation of drug-metabolizing enzymes in infectious and inflammatory disease: implications for biologics-small molecule drug interactions.

PubMed

Mallick, Pankajini; Taneja, Guncha; Moorthy, Bhagavatula; Ghose, Romi

2017-06-01

Drug-metabolizing enzymes (DMEs) are primarily down-regulated during infectious and inflammatory diseases, leading to disruption in the metabolism of small molecule drugs (smds), which are increasingly being prescribed therapeutically in combination with biologics for a number of chronic diseases. The biologics may exert pro- or anti-inflammatory effect, which may in turn affect the expression/activity of DMEs. Thus, patients with infectious/inflammatory diseases undergoing biologic/smd treatment can have complex changes in DMEs due to combined effects of the disease and treatment. Areas covered: We will discuss clinical biologics-SMD interaction and regulation of DMEs during infection and inflammatory diseases. Mechanistic studies will be discussed and consequences on biologic-small molecule combination therapy on disease outcome due to changes in drug metabolism will be highlighted. Expert opinion: The involvement of immunomodulatory mediators in biologic-SMDs is well known. Regulatory guidelines recommend appropriate in vitro or in vivo assessments for possible interactions. The role of cytokines in biologic-SMDs has been documented. However, the mechanisms of drug-drug interactions is much more complex, and is probably multi-factorial. Studies aimed at understanding the mechanism by which biologics effect the DMEs during inflammation/infection are clinically important.

Pharmacological profiles of acute myeloid leukemia treatments in patient samples by automated flow cytometry: a bridge to individualized medicine.

PubMed

Bennett, Teresa A; Montesinos, Pau; Moscardo, Federico; Martinez-Cuadron, David; Martinez, Joaquin; Sierra, Jorge; García, Raimundo; de Oteyza, Jaime Perez; Fernandez, Pascual; Serrano, Josefina; Fernandez, Angeles; Herrera, Pilar; Gonzalez, Ataulfo; Bethancourt, Concepcion; Rodriguez-Macias, Gabriela; Alonso, Arancha; Vera, Juan A; Navas, Begoña; Lavilla, Esperanza; Lopez, Juan A; Jimenez, Santiago; Simiele, Adriana; Vidriales, Belen; Gonzalez, Bernardo J; Burgaleta, Carmen; Hernandez Rivas, Jose A; Mascuñano, Raul Cordoba; Bautista, Guiomar; Perez Simon, Jose A; Fuente, Adolfo de la; Rayón, Consolación; Troconiz, Iñaki F; Janda, Alvaro; Bosanquet, Andrew G; Hernandez-Campo, Pilar; Primo, Daniel; Lopez, Rocio; Liebana, Belen; Rojas, Jose L; Gorrochategui, Julian; Sanz, Miguel A; Ballesteros, Joan

2014-08-01

We have evaluated the ex vivo pharmacology of single drugs and drug combinations in malignant cells of bone marrow samples from 125 patients with acute myeloid leukemia using a novel automated flow cytometry-based platform (ExviTech). We have improved previous ex vivo drug testing with 4 innovations: identifying individual leukemic cells, using intact whole blood during the incubation, using an automated platform that escalates reliably data, and performing analyses pharmacodynamic population models. Samples were sent from 24 hospitals to a central laboratory and incubated for 48 hours in whole blood, after which drug activity was measured in terms of depletion of leukemic cells. The sensitivity of single drugs is assessed for standard efficacy (EMAX) and potency (EC50) variables, ranked as percentiles within the population. The sensitivity of drug-combination treatments is assessed for the synergism achieved in each patient sample. We found a large variability among patient samples in the dose-response curves to a single drug or combination treatment. We hypothesize that the use of the individual patient ex vivo pharmacological profiles may help to guide a personalized treatment selection. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Prostate-Specific Membrane Antigen Targeted Polymersomes for Delivering Mocetinostat and Docetaxel to Prostate Cancer Cell Spheroids.

PubMed

Karandish, Fataneh; Haldar, Manas K; You, Seungyong; Brooks, Amanda E; Brooks, Benjamin D; Guo, Bin; Choi, Yongki; Mallik, Sanku

2016-11-30

Prostate cancer cells overexpress the prostate-specific membrane antigen (PSMA) receptors on the surface. Targeting the PSMA receptor creates a unique opportunity for drug delivery. Docetaxel is a Food and Drug Administration-approved drug for treating metastatic and androgen-independent prostate cancer, and mocetinostat is a potent inhibitor of class I histone deacetylases. In this study, we prepared reduction-sensitive polymersomes presenting folic acid on the surface and encapsulating either docetaxel or mocetinostat. The presence of folic acid allowed efficient targeting of the PSMA receptor and subsequent internalization of the polymeric vesicles in cultured LNCaP prostate cancer cell spheroids. The intracellular reducing agents efficiently released docetaxel and mocetinostat from the polymersomes. The combination of the two drug-encapsulated polymersome formulations significantly ( p < 0.05) decreased the viability of the LNCaP cells (compared to free drugs or control) in three-dimensional spheroid cultures. The calculated combination index value indicated a synergistic effect for the combination of mocetinostat and docetaxel. Thus, our PSMA-targeted drug-encapsulated polymersomes has the potential to lead to a new direction in prostate cancer therapy that decreases the toxicity and increases the efficacy of the drug delivery systems.

Prostate-Specific Membrane Antigen Targeted Polymersomes for Delivering Mocetinostat and Docetaxel to Prostate Cancer Cell Spheroids

PubMed Central

2016-01-01

Prostate cancer cells overexpress the prostate-specific membrane antigen (PSMA) receptors on the surface. Targeting the PSMA receptor creates a unique opportunity for drug delivery. Docetaxel is a Food and Drug Administration-approved drug for treating metastatic and androgen-independent prostate cancer, and mocetinostat is a potent inhibitor of class I histone deacetylases. In this study, we prepared reduction-sensitive polymersomes presenting folic acid on the surface and encapsulating either docetaxel or mocetinostat. The presence of folic acid allowed efficient targeting of the PSMA receptor and subsequent internalization of the polymeric vesicles in cultured LNCaP prostate cancer cell spheroids. The intracellular reducing agents efficiently released docetaxel and mocetinostat from the polymersomes. The combination of the two drug-encapsulated polymersome formulations significantly (p < 0.05) decreased the viability of the LNCaP cells (compared to free drugs or control) in three-dimensional spheroid cultures. The calculated combination index value indicated a synergistic effect for the combination of mocetinostat and docetaxel. Thus, our PSMA-targeted drug-encapsulated polymersomes has the potential to lead to a new direction in prostate cancer therapy that decreases the toxicity and increases the efficacy of the drug delivery systems. PMID:27917408

Antibody-drug conjugates for cancer therapy: The technological and regulatory challenges of developing drug-biologic hybrids.

PubMed

Hamilton, Gregory S

2015-09-01

Antibody-drug conjugates (ADCs) are a new class of therapeutic agents that combine the targeting ability of monoclonal antibodies (mAbs) with small molecule drugs. The combination of a mAb targeting a cancer-specific antigen with a cytotoxin has tremendous promise as a new type of targeted cancer therapy. Two ADCs have been approved and many more are in clinical development, suggesting that this new class of drugs is coming to the forefront. Because of their unique nature as biologic-small drug hybrids, ADCs are challenging to develop, from both the scientific and regulatory perspectives. This review discusses both these aspects in current practice, and surveys the current state of the art of ADC drug development. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Multicomponent Pharmaceutical Cocrystals: A Novel Approach for Combination Therapy.

PubMed

Fatima, Zeeshan; Srivastava, Dipti; Kaur, Chanchal Deep

2018-03-05

Cocrystallization is a technique for modifying the physicochemical and pharmacokinetic properties of an active pharmaceutical ingredient (API) embodying the concept of supramolecular synthon. Most of the examples cited in the literature are of cocrystals formed between an API and a coformer chosen from the generally recognized as safe (GRAS) substance list, however, few examples exist where a cocrystal consists of two or more APIs. These cocrystals are commonly known as multi API, multi drug or drug- drug cocrystals. The formation of such cocrystals is feasible by virtue of non covalent interactions between the APIs, which help them in retaining their biologic activity. In addition, drug- drug cocrystals also offer the potential solution to the limitations such as solubility, stability differences and chemical interaction between the APIs which is often faced during the traditional combination therapy. Cocrystallization of two or more APIs can be employed for delivery of combination drugs for the better and efficacious management of many complex disorders where existing monotherapies do not furnish the desired therapeutic effect. This review on the existing drug-drug cocrystals is to gain insight for better designing of multi API cocrystals with improved physicochemical and pharmacokinetic profile and its application in multiple target therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Partnership to Explore New Drug Combination for Pancreatic Cancer | Frederick National Laboratory for Cancer Research

Cancer.gov

Scientists at NCI and Frederick National Laboratory for Cancer Research (FNLCR) are partnering with the Lustgarten Foundation to test whether a vitamin D derivative will make a difference when combined with a conventional anticancer drug in treating

Pharmacokinetic drug evaluation of saxagliptin plus dapagliflozin for the treatment of type 2 diabetes.

PubMed

Scheen, André J

2017-05-01

Combining a dipeptidyl peptidase-4 inhibitor and a sodium-glucose cotransporter type 2 inhibitor is an attractive option to treat hyperglycaemia in type 2 diabetes. Areas covered: The saxagliptin plus dapagliflozin combination is carefully analysed, focusing on: 1) pharmacokinetic properties, 2) pharmacodynamics data, and 3) results of randomised controlled trials (dual combination versus either monotherapy, sequential therapy saxagliptin added to dapagliflozin or dapagliflozin added to saxagliptin). Expert opinion: Pharmacokinetic findings demonstrate the absence of drug-drug interaction and the bioequivalence of the FDC compared with separated tablets. Pharmacodynamic observations confirm a complementary mode of action of the two agents. Dual saxagliptin-dapagliflozin therapy is more potent than either monotherapy. It may be used as an initial combination, although this approach remains debatable and should probably be reserved in case of high glycated hemoglobin, or a stepwise strategy, according to a personalized approach. The developed saxagliptin-dapagliflozin FDC may simplify anti-hyperglycemic therapy and improve drug compliance.

He-Ne ILLLI used for brain trauma: a clinical observation of 46 cases

NASA Astrophysics Data System (ADS)

Yang, Da-Ke; Ru, Zheng-Guo; Ge, Sheng-Li; Shuo, Wei-Lan

1998-11-01

With the background that ILLLI can lower the viscosity of blood, improve the microcirculation, we investigated and compared the therapeutic effect of conventional drug therapy and ILLLI combined drug therapy for brain trauma. We found that ILLLI combined drug therapy could effectively alleviate some symptoms such as headache, vertigo, nausea, vomiting, blurred vision, anorexia caused by brain trauma. the therapeutic effect of treated group was prior to control group.

Prevalence of Different Combinations of Antiepileptic Drugs and CNS Drugs in Elderly Home Care Service and Nursing Home Patients in Norway.

PubMed

Halvorsen, Kjell H; Johannessen Landmark, Cecilie; Granas, Anne Gerd

2016-01-01

Introduction. Antiepileptic drugs (AEDs) are used to treat different conditions in elderly patients and are among the drug classes most susceptible to be involved in drug-drug interactions (DDI). The aim of the study was to describe and compare use of AEDs between home care service and nursing home patients, as these patients are not included in nationwide databases of drug utilization. In the combined population, we investigate DDI of AEDs with other central nervous system- (CNS-) active drugs and DDIs involving AEDs in general. Materials and Methods. Point-prevalence study of Norwegian patients in home care services and nursing homes in 2009. At the patient level, we screened for different DDIs involving AEDs. Results. In total, 882 patients (7.8%) of 11,254 patients used AEDs and number of users did not differ between home care services and nursing homes (8.2% versus 7.7%). In the combined population, we identified 436 potential DDIs in 45% of the patients. Conclusions. In a large population of elderly, home care service and nursing home patients do not differ with respect to exposure of AEDs but use more AEDs as compared to the general population of similar age. The risk of DDIs with AEDs and other CNS-active drugs should be taken into consideration and individual clinical evaluations are assessed in this population.

Evaluation of Ceftolozane-Tazobactam in Combination with Meropenem against Pseudomonas aeruginosa Sequence Type 175 in a Hollow-Fiber Infection Model.

PubMed

Montero, M; VanScoy, Brian D; López-Causapé, Carla; Conde, Haley; Adams, Jonathan; Segura, Concepción; Zamorano, Laura; Oliver, Antonio; Horcajada, Juan P; Ambrose, Paul G

2018-05-01

The aim of this study was to investigate the efficacy of ceftolozane-tazobactam in combination with meropenem against an extensively drug-resistant (XDR) Pseudomonas aeruginosa high-risk clone, sequence type 175, isolated in a Spanish university hospital. A 14-day hollow-fiber infection model was used to simulate clinical exposure of the two drug regimens alone and in combination, and serial samples were collected to determine drug concentrations and CFU counts. The untreated control failed, as did each study regimen when administered alone. However, when ceftolozane-tazobactam was administered in combination with meropenem, there was a >4-log 10 CFU/ml bacterial density reduction and suppression of resistance for the duration of the study. These data suggest that ceftolozane-tazobactam plus meropenem may be a useful combination for treating XDR P. aeruginosa . Copyright © 2018 American Society for Microbiology.

[Effect of psychotropic drugs on activity of anticonvulsants in maximal electroshock test].

PubMed

Alikina, N A; Tregubov, A L; Kotegov, V P

2010-08-01

The effect ofpsychotropic drugs on the pharmacological properties of anticonvulsants was studied on white mice under maximal electroshock (ME) test conditions. Changes in the anticonvulsant effect of phenobarbital, diphenin, carbamazepine, hexamidine were traced upon their joint administration with psychotropic drugs, including piracetam, aminalon, amitriptyline, imizine, levomepromazine, and lithium oxybutyrate. An important result of research is the fact, that in no one of combinations the basic pharmacological effect of anticonvulsants was decreased. Based on the results of experiments, the most rational combinations of anticonvulsants with psychotropic preparations were revealed as manifested in the ME test. As criterion of rational combination was the increase in the activity of anticonvulsants and reduction of their toxicity in combination or at least invariance of this parameter. Rational combinations include (i) phenobarbital with piracetam, amitriptyline, levomepromazine, and lithium oxybutyrate; (ii) carbamazepine with piracetam; and (iii) hexamidine with amitriptyline, levomepromazine and imizine.

A pragmatic definition of therapeutic synergy suitable for clinically relevant in vitro multicompound analyses.

PubMed

Kashif, Muhammad; Andersson, Claes; Åberg, Magnus; Nygren, Peter; Sjöblom, Tobias; Hammerling, Ulf; Larsson, Rolf; Gustafsson, Mats G

2014-07-01

For decades, the standard procedure when screening for candidate anticancer drug combinations has been to search for synergy, defined as any positive deviation from trivial cases like when the drugs are regarded as diluted versions of each other (Loewe additivity), independent actions (Bliss independence), or no interaction terms in a response surface model (no interaction). Here, we show that this kind of conventional synergy analysis may be completely misleading when the goal is to detect if there is a promising in vitro therapeutic window. Motivated by this result, and the fact that a drug combination offering a promising therapeutic window seldom is interesting if one of its constituent drugs can provide the same window alone, the largely overlooked concept of therapeutic synergy (TS) is reintroduced. In vitro TS is said to occur when the largest therapeutic window obtained by the best drug combination cannot be achieved by any single drug within the concentration range studied. Using this definition of TS, we introduce a procedure that enables its use in modern massively parallel experiments supported by a statistical omnibus test for TS designed to avoid the multiple testing problem. Finally, we suggest how one may perform TS analysis, via computational predictions of the reference cell responses, when only the target cell responses are available. In conclusion, the conventional error-prone search for promising drug combinations may be improved by replacing conventional (toxicology-rooted) synergy analysis with an analysis focused on (clinically motivated) TS. ©2014 American Association for Cancer Research.

Drug repurposing identifies a synergistic combination therapy with imatinib mesylate for gastrointestinal stromal tumor.

PubMed

Pessetto, Ziyan Y; Ma, Yan; Hirst, Jeff J; von Mehren, Margaret; Weir, Scott J; Godwin, Andrew K

2014-10-01

Gastrointestinal stromal tumor (GIST) is a rare and therefore often neglected disease. Introduction of the kinase inhibitor imatinib mesylate radically improved the clinical response of patients with GIST; however, its effects are often short-lived, with GISTs demonstrating a median time-to-progression of approximately two years. Although many investigational drugs, approved first for other cancers, have been subsequently evaluated for the management of GIST, few have greatly affected the overall survival of patients with advanced disease. We employed a novel, focused, drug-repurposing effort for GIST, including imatinib mesylate-resistant GIST, evaluating a large library of FDA-approved drugs regardless of current indication. As a result of the drug-repurposing screen, we identified eight FDA-approved drugs, including fludarabine phosphate (F-AMP), that showed synergy with and/or overcame resistance to imatinib mesylate. F-AMP induces DNA damage, Annexin V, and caspase-3/7 activities as the cytotoxic effects on GIST cells, including imatinib mesylate-resistant GIST cells. F-AMP and imatinib mesylate combination treatment showed greater inhibition of GIST cell proliferation when compared with imatinib mesylate and F-AMP alone. Successful in vivo experiments confirmed the combination of imatinib mesylate with F-AMP enhanced the antitumor effects compared with imatinib mesylate alone. Our results identified F-AMP as a promising, repurposed drug therapy for the treatment of GISTs, with potential to be administered in combination with imatinib mesylate or for treatment of imatinib mesylate-refractory tumors. ©2014 American Association for Cancer Research.

Cell biological effects of hyperthermia alone or combined with radiation or drugs: a short introduction to newcomers in the field.

PubMed

Kampinga, Harm H

2006-05-01

Hyperthermia results in protein unfolding that, if not properly chaperoned by Heat Shock Proteins (HSP), can lead to irreversible and toxic protein aggregates. Elevating HSP prior to heating makes cells thermotolerant. Hyperthermia also can enhance the sensitivity of cells to radiation and drugs. This sensitization to drugs or radiation is not directly related to altered HSP expression. However, altering HSP expression before heat and radiation or drug treatment will affect the extent of thermal sensitization because the HSP will attenuate the heat-induced protein damage that is responsible for radiation- or drug-sensitization. For thermal radiosensitization, nuclear protein damage is considered to be responsible for hyperthermic effects on DNA repair, in particular base excision repair. Hyperthermic drug sensitization can be seen for a number of anti-cancer drugs, especially of alkylating agents. Synergy between heat and drugs may arise from multiple events such as heat damage to ABC transporters (drug accumulation), intra-cellular drug detoxification pathways and repair of drug-induced DNA adducts. This may be why cells with acquired drug resistance (often multi-factorial) can be made responsive to drugs again by combining the drug treatment with heat.

High-throughput combinatorial screening identifies drugs that cooperate with ibrutinib to kill activated B-cell–like diffuse large B-cell lymphoma cells

PubMed Central

Mathews Griner, Lesley A.; Guha, Rajarshi; Shinn, Paul; Young, Ryan M.; Keller, Jonathan M.; Liu, Dongbo; Goldlust, Ian S.; Yasgar, Adam; McKnight, Crystal; Boxer, Matthew B.; Duveau, Damien Y.; Jiang, Jian-Kang; Michael, Sam; Mierzwa, Tim; Huang, Wenwei; Walsh, Martin J.; Mott, Bryan T.; Patel, Paresma; Leister, William; Maloney, David J.; Leclair, Christopher A.; Rai, Ganesha; Jadhav, Ajit; Peyser, Brian D.; Austin, Christopher P.; Martin, Scott E.; Simeonov, Anton; Ferrer, Marc; Staudt, Louis M.; Thomas, Craig J.

2014-01-01

The clinical development of drug combinations is typically achieved through trial-and-error or via insight gained through a detailed molecular understanding of dysregulated signaling pathways in a specific cancer type. Unbiased small-molecule combination (matrix) screening represents a high-throughput means to explore hundreds and even thousands of drug–drug pairs for potential investigation and translation. Here, we describe a high-throughput screening platform capable of testing compounds in pairwise matrix blocks for the rapid and systematic identification of synergistic, additive, and antagonistic drug combinations. We use this platform to define potential therapeutic combinations for the activated B-cell–like subtype (ABC) of diffuse large B-cell lymphoma (DLBCL). We identify drugs with synergy, additivity, and antagonism with the Bruton’s tyrosine kinase inhibitor ibrutinib, which targets the chronic active B-cell receptor signaling that characterizes ABC DLBCL. Ibrutinib interacted favorably with a wide range of compounds, including inhibitors of the PI3K-AKT-mammalian target of rapamycin signaling cascade, other B-cell receptor pathway inhibitors, Bcl-2 family inhibitors, and several components of chemotherapy that is the standard of care for DLBCL. PMID:24469833

A Reactive 1O2 - Responsive Combined Treatment System of Photodynamic and Chemotherapy for Cancer

NASA Astrophysics Data System (ADS)

Wang, Xiaojun; Meng, Guoqing; Zhang, Song; Liu, Xinli

2016-07-01

The development of reactive oxygen species (ROS)-responsive drug delivery and drug release has gradually attracted much attention in recent years as a promising therapeutic strategy. Singlet oxygen (1O2) as the major ROS species is widely used in photodynamic therapy (PDT) of cancer. In the present study, we introduce a combined treatment using ROS-sensitive thioketal (TK) linkage as a linker between upconversion nanoparticles (UNs)-based PDT and doxorubicin (DOX)-based chemotherapy. UNs can not only play a role in PDT, but can also be used as a nanocarrier for drug delivery of DOX. Moreover, the products of 1O2 during PDT are able to cleave TK linker inducing the release of DOX which can further achieve the goal of chemotherapy. By using this 1O2-responsive nanocarrier delivery system, DOX can easily reach the tumor site and be accumulated in the nuclei to effectively kill the cancer cells, and therefore decreasing the side effects of chemotherapy on the body. Thus, PDT also has the function of controlling drug release in this combination treatment strategy. Compared with monotherapy, the combination of PDT with chemotherapy also possesses excellent drug loading capability and anticancer efficiency.

Combining naltrexone and prazosin in a single oral medication decreases alcohol drinking more effectively than does either drug alone.

PubMed

Froehlich, Janice C; Hausauer, Brett J; Rasmussen, Dennis D

2013-10-01

Naltrexone (NTX) is underutilized in clinical treatment settings because its efficacy is modest, and it is not effective for all alcoholics and, when it is effective, a significant number of alcoholics fail to maintain initial treatment gains and subsequently relapse to heavy drinking. This has slowed acceptance of NTX by the treatment community, and there is a clear need for additional treatments for alcoholism and alcohol use disorders. Given that NTX and prazosin can each reduce alcohol drinking in rats selectively bred for alcohol preference and high voluntary alcohol drinking (alcohol-preferring "P" rats), we tested whether a combination of NTX + prazosin is more effective in decreasing alcohol drinking than is either drug alone. P rats were given access to a 15% (v/v) alcohol solution for 2 hours daily. Rats were fed NTX and prazosin, alone or in combination, prior to onset of the daily 2-hour alcohol access period for 4 weeks and the effect of drug treatment on alcohol and water intake was assessed. During the first week of treatment, neither a low dose of NTX, nor prazosin, was effective in decreasing alcohol intake when each drug was administered alone, but combining the 2 drugs in a single medication significantly reduced alcohol intake. The combination was as effective as was a higher dose of NTX. Using a low dose of NTX in combination with prazosin may reduce the potential for undesirable side effects early in treatment which, in turn, may improve patient compliance and result in a more successful outcome when NTX is used for treating alcoholism and alcohol use disorders. Combining low-dose NTX and prazosin in a single medication may be more useful than is either drug alone for treating both inpatient and outpatient alcoholics and heavy drinkers early in the treatment process. Copyright © 2013 by the Research Society on Alcoholism.

Combined Effects of Acamprosate and Escitalopram on Ethanol Consumption in Mice

PubMed Central

Ho, Ada Man-Choi; Qiu, Yanyan; Jia, Yun-Fang; Aguiar, Felipe S.; Hinton, David J.; Karpyak, Victor M.; Weinshilboum, Richard M.; Choi, Doo-Sup

2016-01-01

Background Major depression is one of the most prevalent psychiatry comorbidities of alcohol use disorders (AUD). Since negative emotions can trigger craving and increase the risk of relapse, treatments that target both conditions simultaneously may augment treatment success. Previous studies showed a potential synergist effect of FDA approved medication for AUD acamprosate and the antidepressant escitalopram. In this study, we investigated the effects of combining acamprosate and escitalopram on ethanol consumption in stress-induced depressed mice. Methods Forty singly-housed C57BL/6J male mice were subjected to chronic unpredictable stress. In parallel, 40 group-housed male mice were subjected to normal husbandry. After 3 weeks, depressive- and anxiety-like behaviors and ethanol consumption were assessed. For the next 7 days, mice were injected with saline, acamprosate (200 mg/kg; twice/day), escitalopram (5 mg/kg; twice/day), or their combination (n = 9–11/drug group/stress group). Two-bottle choice limited access drinking of 15% ethanol and tap water was performed 3 hours into dark phase for 2 hours immediately after the dark phase daily injection. Ethanol drinking was monitored for another 7 days without drug administration. Results Mice subjected to the chronic unpredictable stress paradigm for 3 weeks showed apparent depression- and anxiety-like behaviors compared to their non-stressed counterparts including longer immobility time in the forced swim test and lower sucrose preference. Stressed mice also displayed higher ethanol consumption and preference in a 2-bottle choice drinking test. During the drug administration period, the escitalopram-only and combined drug groups showed significant reduction in ethanol consumption in non-stressed mice, while only the combined drug group showed significantly reduced consumption in stressed mice. However, such reduction did not persist into the post-drug administration period. Conclusions The combination of acamprosate and escitalopram suppressed ethanol intake in both non-stressed and stressed mice, hence this combination is potentially helpful for AUD individuals with or without comorbid depression to reduce alcohol use. PMID:27184383

Moving Synergistically Acting Drug Combinations to the Clinic by Comparing Sequential versus Simultaneous Drug Administrations.

PubMed

Dinavahi, Saketh S; Noory, Mohammad A; Gowda, Raghavendra; Drabick, Joseph J; Berg, Arthur; Neves, Rogerio I; Robertson, Gavin P

2018-03-01

Drug combinations acting synergistically to kill cancer cells have become increasingly important in melanoma as an approach to manage the recurrent resistant disease. Protein kinase B (AKT) is a major target in this disease but its inhibitors are not effective clinically, which is a major concern. Targeting AKT in combination with WEE1 (mitotic inhibitor kinase) seems to have potential to make AKT-based therapeutics effective clinically. Since agents targeting AKT and WEE1 have been tested individually in the clinic, the quickest way to move the drug combination to patients would be to combine these agents sequentially, enabling the use of existing phase I clinical trial toxicity data. Therefore, a rapid preclinical approach is needed to evaluate whether simultaneous or sequential drug treatment has maximal therapeutic efficacy, which is based on a mechanistic rationale. To develop this approach, melanoma cell lines were treated with AKT inhibitor AZD5363 [4-amino- N -[(1 S )-1-(4-chlorophenyl)-3-hydroxypropyl]-1-(7 H -pyrrolo[2,3- d ]pyrimidin-4-yl)piperidine-4-carboxamide] and WEE1 inhibitor AZD1775 [2-allyl-1-(6-(2-hydroxypropan-2-yl)pyridin-2-yl)-6-((4-(4-methylpiperazin-1-yl)phenyl)amino)-1 H -pyrazolo[3,4- d ]pyrimidin-3(2 H )-one] using simultaneous and sequential dosing schedules. Simultaneous treatment synergistically reduced melanoma cell survival and tumor growth. In contrast, sequential treatment was antagonistic and had a minimal tumor inhibitory effect compared with individual agents. Mechanistically, simultaneous targeting of AKT and WEE1 enhanced deregulation of the cell cycle and DNA damage repair pathways by modulating transcription factors p53 and forkhead box M1, which was not observed with sequential treatment. Thus, this study identifies a rapid approach to assess the drug combinations with a mechanistic basis for selection, which suggests that combining AKT and WEE1 inhibitors is needed for maximal efficacy. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Theoretical basis, experimental design, and computerized simulation of synergism and antagonism in drug combination studies.

PubMed

Chou, Ting-Chao

2006-09-01

The median-effect equation derived from the mass-action law principle at equilibrium-steady state via mathematical induction and deduction for different reaction sequences and mechanisms and different types of inhibition has been shown to be the unified theory for the Michaelis-Menten equation, Hill equation, Henderson-Hasselbalch equation, and Scatchard equation. It is shown that dose and effect are interchangeable via defined parameters. This general equation for the single drug effect has been extended to the multiple drug effect equation for n drugs. These equations provide the theoretical basis for the combination index (CI)-isobologram equation that allows quantitative determination of drug interactions, where CI < 1, = 1, and > 1 indicate synergism, additive effect, and antagonism, respectively. Based on these algorithms, computer software has been developed to allow automated simulation of synergism and antagonism at all dose or effect levels. It displays the dose-effect curve, median-effect plot, combination index plot, isobologram, dose-reduction index plot, and polygonogram for in vitro or in vivo studies. This theoretical development, experimental design, and computerized data analysis have facilitated dose-effect analysis for single drug evaluation or carcinogen and radiation risk assessment, as well as for drug or other entity combinations in a vast field of disciplines of biomedical sciences. In this review, selected examples of applications are given, and step-by-step examples of experimental designs and real data analysis are also illustrated. The merging of the mass-action law principle with mathematical induction-deduction has been proven to be a unique and effective scientific method for general theory development. The median-effect principle and its mass-action law based computer software are gaining increased applications in biomedical sciences, from how to effectively evaluate a single compound or entity to how to beneficially use multiple drugs or modalities in combination therapies.

Application of Pharmacokinetic and Pharmacodynamic Analysis to the Development of Liposomal Formulations for Oncology

PubMed Central

Ait-Oudhia, Sihem; Mager, Donald E.; Straubinger, Robert M.

2014-01-01

Liposomal formulations of anticancer agents have been developed to prolong drug circulating lifetime, enhance anti-tumor efficacy by increasing tumor drug deposition, and reduce drug toxicity by avoiding critical normal tissues. Despite the clinical approval of numerous liposome-based chemotherapeutics, challenges remain in the development and clinical deployment of micro- and nano-particulate formulations, as well as combining these novel agents with conventional drugs and standard-of-care therapies. Factors requiring optimization include control of drug biodistribution, release rates of the encapsulated drug, and uptake by target cells. Quantitative mathematical modeling of formulation performance can provide an important tool for understanding drug transport, uptake, and disposition processes, as well as their role in therapeutic outcomes. This review identifies several relevant pharmacokinetic/pharmacodynamic models that incorporate key physical, biochemical, and physiological processes involved in delivery of oncology drugs by liposomal formulations. They capture observed data, lend insight into factors determining overall antitumor response, and in some cases, predict conditions for optimizing chemotherapy combinations that include nanoparticulate drug carriers. PMID:24647104

Evidence-Based Design of Fixed-Dose Combinations: Principles and Application to Pediatric Anti-Tuberculosis Therapy.

PubMed

Svensson, Elin M; Yngman, Gunnar; Denti, Paolo; McIlleron, Helen; Kjellsson, Maria C; Karlsson, Mats O

2018-05-01

Fixed-dose combination formulations where several drugs are included in one tablet are important for the implementation of many long-term multidrug therapies. The selection of optimal dose ratios and tablet content of a fixed-dose combination and the design of individualized dosing regimens is a complex task, requiring multiple simultaneous considerations. In this work, a methodology for the rational design of a fixed-dose combination was developed and applied to the case of a three-drug pediatric anti-tuberculosis formulation individualized on body weight. The optimization methodology synthesizes information about the intended use population, the pharmacokinetic properties of the drugs, therapeutic targets, and practical constraints. A utility function is included to penalize deviations from the targets; a sequential estimation procedure was developed for stable estimation of break-points for individualized dosing. The suggested optimized pediatric anti-tuberculosis fixed-dose combination was compared with the recently launched World Health Organization-endorsed formulation. The optimized fixed-dose combination included 15, 36, and 16% higher amounts of rifampicin, isoniazid, and pyrazinamide, respectively. The optimized fixed-dose combination is expected to result in overall less deviation from the therapeutic targets based on adult exposure and substantially fewer children with underexposure (below half the target). The development of this design tool can aid the implementation of evidence-based formulations, integrating available knowledge and practical considerations, to optimize drug exposures and thereby treatment outcomes.

The Prediction of Drug-Disease Correlation Based on Gene Expression Data.

PubMed

Cui, Hui; Zhang, Menghuan; Yang, Qingmin; Li, Xiangyi; Liebman, Michael; Yu, Ying; Xie, Lu

2018-01-01

The explosive growth of high-throughput experimental methods and resulting data yields both opportunity and challenge for selecting the correct drug to treat both a specific patient and their individual disease. Ideally, it would be useful and efficient if computational approaches could be applied to help achieve optimal drug-patient-disease matching but current efforts have met with limited success. Current approaches have primarily utilized the measureable effect of a specific drug on target tissue or cell lines to identify the potential biological effect of such treatment. While these efforts have met with some level of success, there exists much opportunity for improvement. This specifically follows the observation that, for many diseases in light of actual patient response, there is increasing need for treatment with combinations of drugs rather than single drug therapies. Only a few previous studies have yielded computational approaches for predicting the synergy of drug combinations by analyzing high-throughput molecular datasets. However, these computational approaches focused on the characteristics of the drug itself, without fully accounting for disease factors. Here, we propose an algorithm to specifically predict synergistic effects of drug combinations on various diseases, by integrating the data characteristics of disease-related gene expression profiles with drug-treated gene expression profiles. We have demonstrated utility through its application to transcriptome data, including microarray and RNASeq data, and the drug-disease prediction results were validated using existing publications and drug databases. It is also applicable to other quantitative profiling data such as proteomics data. We also provide an interactive web interface to allow our Prediction of Drug-Disease method to be readily applied to user data. While our studies represent a preliminary exploration of this critical problem, we believe that the algorithm can provide the basis for further refinement towards addressing a large clinical need.

Novel approach for a PTX/VEGF dual drug delivery system in cardiovascular applications-an innovative bulk and surface drug immobilization.

PubMed

Wulf, Katharina; Teske, Michael; Matschegewski, Claudia; Arbeiter, Daniela; Bajer, Dalibor; Eickner, Thomas; Schmitz, Klaus-Peter; Grabow, Niels

2018-06-01

The successive incorporation of several drugs into the polymeric bulk of implants mostly results in loss of considerable quantity of one drug, and/or the loss in quality of the coating and also in changes of drug release time points. A dual drug delivery system (DDDS) based on poly-L-lactide (PLLA) copolymers combining the effective inhibition of smooth muscle cell proliferation while simultaneously promoting re-endothelialization was successfully developed. To overcome possible antagonistic drug interactions and the limitation of the polymeric bulk material as release system for dual drugs, a novel concept which combines the bulk and surface drug immobilization for a DDDS was investigated. The advantage of this DDDS is that the bulk incorporation of fluorescein diacetate (FDAc) (model drug for paclitaxel (PTX)) via spray coating enhanced the subsequent cleavable surface coupling of vascular endothelial growth factor (VEGF) via the crosslinker bissulfosuccinimidyl suberate (BS 3 ). In the presence of the embedded FDAc, the VEGF loading and release are about twice times higher than in absence. Furthermore, the DDDS combines the diffusion drug delivery (FDAc or PTX) and the chemical controlled drug release, VEGF via hydrolysable ester bonds, without loss in quantity and quality of the drug release curves. Additionally, the performed in vitro biocompatibility study showed the bimodal influences of PTX and VEGF on human endothelial EA.hy926 cells. In conclusion, it was possible to show the feasibility to develop a novel DDDS which has a high potential for the medical application due to the possible easy and short modification of a polymer-based PTX delivery system.

Water-soluble polymer–drug conjugates for combination chemotherapy against visceral leishmaniasis

PubMed Central

Nicoletti, Salvatore; Seifert, Karin; Gilbert, Ian H.

2010-01-01

There is a need for new safe, effective and short-course treatments for leishmaniasis; one strategy is to use combination chemotherapy. Polymer–drug conjugates have shown promise for the delivery of anti-leishmanial agents such as amphotericin B. In this paper, we report on the preparation and biological evaluation of polymer–drug conjugates of N-(2-hydroxypropyl)methacrylamide (HPMA), amphotericin B and alendronic acid. The combinatorial polymer–drug conjugates were effective anti-leishmanial agents in vitro and in vivo, but offered no advantage over the single poly(HPMA)–amphotericin B conjugates. PMID:20338769

Multiple heart-cutting and comprehensive two-dimensional liquid chromatography hyphenated to mass spectrometry for the characterization of the antibody-drug conjugate ado-trastuzumab emtansine.

PubMed

Sandra, Koen; Vanhoenacker, Gerd; Vandenheede, Isabel; Steenbeke, Mieke; Joseph, Maureen; Sandra, Pat

2016-10-01

Antibody-drug conjugates might be the magic bullets referred to by Paul Ehrlich over 100 years ago. Together with a huge therapeutic potential, these molecules come with a structural complexity that drives state-of-the-art chromatography and mass spectrometry to its limits. The use of multiple heart-cutting (mLC-LC) and comprehensive (LC×LC) multidimensional LC in combination with high resolution mass spectrometry for the characterization of the lysine conjugated antibody-drug conjugate ado-trastuzumab emtansine, commercialized as Kadcyla, is presented. By combining protein and peptide measurements, attributes such as drug loading, drug distribution and drug conjugation sites can be assessed in an elegant manner. Copyright © 2016 Elsevier B.V. All rights reserved.

Combining metformin and nelfinavir exhibits synergistic effects against the growth of human cervical cancer cells and xenograft in nude mice.

PubMed

Xia, Chenglai; Chen, Ruihong; Chen, Jinman; Qi, Qianqian; Pan, Yanbin; Du, Lanying; Xiao, Guohong; Jiang, Shibo

2017-03-02

Human cervical cancer is the fourth most common carcinoma in women worldwide. However, the emergence of drug resistance calls for continuously developing new anticancer drugs and combination chemotherapy regimens. The present study aimed to investigate the anti-cervical cancer effects of metformin, a first-line therapeutic drug for type 2 diabetes mellitus, and nelfinavir, an HIV protease inhibitor, when used alone or in combination. We found that both metformin and nelfinavir, when used alone, were moderately effective in inhibiting proliferation, inducing apoptosis and suppressing migration and invasion of human cervical cell lines HeLa, SiHa and CaSki. When used in combination, these two drugs acted synergistically to inhibit the growth of human cervical cancer cells in vitro and cervical cancer cell xenograft in vivo in nude mice, and suppress cervical cancer cell migration and invasion. The protein expression of phosphoinositide 3-kinase catalytic subunit PI3K(p110α), which can promote tumor growth, was remarkably downregulated, while the tumor suppressor proteins p53 and p21 were substantially upregulated following the combinational treatment in vitro and in vivo. These results suggest that clinical use of metformin and nelfinavir in combination is expected to have synergistic antitumor efficacy and significant potential for the treatment of human cervical cancer.

77 FR 22327 - Draft Guidance for Industry on New Animal Drugs and New Animal Drug Combination Products...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-13

... or on Medicated Feed or Drinking Water of Food-Producing Animals: Recommendations for Drug Sponsors for Voluntarily Aligning Product Use Conditions With GFI 209; Availability AGENCY: Food and Drug... availability of a draft guidance for industry (draft GFI 213) entitled ``New Animal Drugs and New Animal Drug...

Drug synergy screen and network modeling in dedifferentiated liposarcoma identifies CDK4 and IGF1R as synergistic drug targets.

PubMed

Miller, Martin L; Molinelli, Evan J; Nair, Jayasree S; Sheikh, Tahir; Samy, Rita; Jing, Xiaohong; He, Qin; Korkut, Anil; Crago, Aimee M; Singer, Samuel; Schwartz, Gary K; Sander, Chris

2013-09-24

Dedifferentiated liposarcoma (DDLS) is a rare but aggressive cancer with high recurrence and low response rates to targeted therapies. Increasing treatment efficacy may require combinations of targeted agents that counteract the effects of multiple abnormalities. To identify a possible multicomponent therapy, we performed a combinatorial drug screen in a DDLS-derived cell line and identified cyclin-dependent kinase 4 (CDK4) and insulin-like growth factor 1 receptor (IGF1R) as synergistic drug targets. We measured the phosphorylation of multiple proteins and cell viability in response to systematic drug combinations and derived computational models of the signaling network. These models predict that the observed synergy in reducing cell viability with CDK4 and IGF1R inhibitors depends on the activity of the AKT pathway. Experiments confirmed that combined inhibition of CDK4 and IGF1R cooperatively suppresses the activation of proteins within the AKT pathway. Consistent with these findings, synergistic reductions in cell viability were also found when combining CDK4 inhibition with inhibition of either AKT or epidermal growth factor receptor (EGFR), another receptor similar to IGF1R that activates AKT. Thus, network models derived from context-specific proteomic measurements of systematically perturbed cancer cells may reveal cancer-specific signaling mechanisms and aid in the design of effective combination therapies.

Drug Synergy Screen and Network Modeling in Dedifferentiated Liposarcoma Identifies CDK4 and IGF1R as Synergistic Drug Targets

PubMed Central

Miller, Martin L.; Molinelli, Evan J.; Nair, Jayasree S.; Sheikh, Tahir; Samy, Rita; Jing, Xiaohong; He, Qin; Korkut, Anil; Crago, Aimee M.; Singer, Samuel; Schwartz, Gary K.; Sander, Chris

2014-01-01

Dedifferentiated liposarcoma (DDLS) is a rare but aggressive cancer with high recurrence and low response rates to targeted therapies. Increasing treatment efficacy may require combinations of targeted agents that counteract the effects of multiple abnormalities. To identify a possible multicomponent therapy, we performed a combinatorial drug screen in a DDLS-derived cell line and identified cyclin-dependent kinase 4 (CDK4) and insulin-like growth factor 1 receptor (IGF1R) as synergistic drug targets. We measured the phosphorylation of multiple proteins and cell viability in response to systematic drug combinations and derived computational models of the signaling network. These models predict that the observed synergy in reducing cell viability with CDK4 and IGF1R inhibitors depend on activity of the AKT pathway. Experiments confirmed that combined inhibition of CDK4 and IGF1R cooperatively suppresses the activation of proteins within the AKT pathway. Consistent with these findings, synergistic reductions in cell viability were also found when combining CDK4 inhibition with inhibition of either AKT or epidermal growth factor receptor (EGFR), another receptor similar to IGF1R that activates AKT. Thus, network models derived from context-specific proteomic measurements of systematically perturbed cancer cells may reveal cancer-specific signaling mechanisms and aid in the design of effective combination therapies. PMID:24065146

PDE5 Inhibitors Enhance Celecoxib Killing in Multiple Tumor Types

PubMed Central

BOOTH, LAURENCE; ROBERTS, JANE L.; CRUICKSHANKS, NICHOLA; TAVALLAI, SEYEDMEHRAD; WEBB, TIMOTHY; SAMUEL, PETER; CONLEY, ADAM; BINION, BRITTANY; YOUNG, HAROLD F.; POKLEPOVIC, ANDREW; SPIEGEL, SARAH; DENT, PAUL

2015-01-01

The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 activation was dependent on nitric oxide and ceramide signaling. CD95 signaling activated the JNK pathway and inhibition of JNK suppressed cell killing. The drug combination inactivated mTOR and increased the levels of autophagy and knock down of Beclin1 or ATG5 strongly suppressed killing by the drug combination. The drug combination caused an ER stress response; knock down of IRE1α/XBP1 enhanced killing whereas knock down of eIF2α/ATF4/CHOP suppressed killing. Sildenafil and celecoxib treatment suppressed the growth of mammary tumors in vivo. Collectively our data demonstrate that clinically achievable concentrations of celecoxib and sildenafil have the potential to be a new therapeutic approach for cancer. PMID:25303541

Treatment efficacy of anti-hypertensive drugs in monotherapy or combination

PubMed Central

Paz, Marco A.; de-La-Sierra, Alejandro; Sáez, Marc; Barceló, María Antonia; Rodríguez, Juan José; Castro, Sonia; Lagarón, Cristina; Garrido, Josep M; Vera, Pilar; Coll-de-Tuero, Gabriel

2016-01-01

Abstract Background: The relative efficacy of antihypertensive drugs/combinations is not well known. Identifying the most effective ones and the patients’ characteristics associated with best performance of the drugs will improve management of hypertensive patients. Objective: To assess the blood pressure (BP) reduction attributed to antihypertensive drugs and identify characteristics associated with BP decrease. Data sources: MEDLINE, Cochrane Central Register of Controlled Trials from inception through July 2012 and selected papers. Study eligibility criteria: Double-blind, randomized clinical trials whose main result was the reduction in BP by antihypertensive treatment, with study population ≥50 or ≥25 if the study was a crossover, follow-up of at least 8 weeks, and available required data. Study appraisal and synthesis methods: Study data were independently extracted by multiple observers and introduced in an electronic database. Inconsistencies were resolved by discussion and referral back to the original articles. Meta-analysis was performed according to PRISMA statement and using a Bayesian framework. Main Outcome(s) and Measure(s): Mean decrease in systolic (SBP) and diastolic blood pressure (DBP) achieved by each drug or combination. Results: Two hundred eight trials including 94,305 patients were identified. In monotherapy, most drugs achieved 10 to 15 mm Hg SBP and 8 to 10 mm Hg DBP decreases. Olmesartan/amlodipine, olmesartan/hydrochlorothiazide, felodipine/metoprolol, and valsartan/hydrochlorothiazide were the combinations leading to the greatest mean SBP reductions (>20 mm Hg). Female sex and body mass index >25 kg/m2 were associated with more pronounced SBP and DBP reductions, whereas Afro-American ethnicity was associated with BP reductions smaller than the median. Results were adjusted by study duration, cardiovascular disease, and diabetes mellitus. Still, the estimation was performed using the mean administered doses, which do not exactly match those of the available drug formats. Limitations: Data corresponded to those obtained in each of the included trials; the analysis of the combinations was limited to the most recent ones; estimations were performed using the mean administered doses. Conclusions and implications: Certain drug combinations achieve BP reductions ranging from 20 to 25/10 to 15 mm Hg. Sex, ethnicity, and obesity are associated with antihypertensive response. This information can contribute to better selection of the antihypertensive drug, depending on the magnitude of pretreatment BP elevation. Guidelines should be revised. PMID:27472680

"Dark" Singlet Oxygen and Electron Paramagnetic Resonance Spin Trapping as Convenient Tools to Assess Photolytic Drug Degradation.

PubMed

Persich, Peter; Hostyn, Steven; Joie, Céline; Winderickx, Guy; Pikkemaat, Jeroen; Romijn, Edwin P; Maes, Bert U W

2017-05-01

Forced degradation studies are an important tool for a systematic assessment of decomposition pathways and identification of reactive sites in active pharmaceutical ingredients (APIs). Two methodologies have been combined in order to provide a deeper understanding of singlet oxygen-related degradation pathways of APIs under light irradiation. First, we report that a "dark" singlet oxygen test enables the investigation of drug reactivity toward singlet oxygen independently of photolytic irradiation processes. Second, the photosensitizing properties of the API producing the singlet oxygen was proven and quantified by spin trapping and electron paramagnetic resonance analysis. A combination of these techniques is an interesting addition to the forced degradation portfolio as it can be used for (1) revealing unexpected degradation pathways of APIs due to singlet oxygen, (2) clarifying photolytic drug-drug interactions in fixed-dose combinations, and (3) synthesizing larger quantities of hardly accessible oxidative drug degradants. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Current perspectives on the mechanism of action of artemisinins.

PubMed

Golenser, Jacob; Waknine, Judith H; Krugliak, Miriam; Hunt, Nicholas H; Grau, Georges E

2006-12-01

Artemisinin derivatives are the most recent single drugs approved and introduced for public antimalarial treatment. Although their recommended use is for treatment of Plasmodium falciparum infection, these drugs also act against other parasites, as well as against tumor cells. The mechanisms of action attributed to artemisinin include interference with parasite transport proteins, disruption of parasite mitochondrial function, modulation of host immune function and inhibition of angiogenesis. Artemisinin combination therapies are currently the preferred treatment for malaria. These combinations may prevent the induction of parasite drug resistance. However, in view of the multiple mechanisms involved, especially when additional drugs are used, the combined therapy should be carefully examined for antagonistic effects. It is now a general theory that the crucial mechanism is interference with plasmodial SERCA. Therefore, future development of resistance may be associated with overproduction or mutations of this transporter. However, a general mechanism, such as alterations in general drug transport pathways, is feasible. In this article, we review the evidence for each mechanism of action suggested.

Multifaceted remodeling by vitamin C boosts sensitivity of Mycobacterium tuberculosis subpopulations to combination treatment by anti-tubercular drugs.

PubMed

Sikri, Kriti; Duggal, Priyanka; Kumar, Chanchal; Batra, Sakshi Dhingra; Vashist, Atul; Bhaskar, Ashima; Tripathi, Kritika; Sethi, Tavpritesh; Singh, Amit; Tyagi, Jaya Sivaswami

2018-05-01

Bacterial dormancy is a major impediment to the eradication of tuberculosis (TB), because currently used drugs primarily target actively replicating bacteria. Therefore, decoding of the critical survival pathways in dormant tubercle bacilli is a research priority to formulate new approaches for killing these bacteria. Employing a network-based gene expression analysis approach, we demonstrate that redox active vitamin C (vit C) triggers a multifaceted and robust adaptation response in Mycobacterium tuberculosis (Mtb) involving ~ 67% of the genome. Vit C-adapted bacteria display well-described features of dormancy, including growth stasis and progression to a viable but non-culturable (VBNC) state, loss of acid-fastness and reduction in length, dissipation of reductive stress through triglyceride (TAG) accumulation, protective response to oxidative stress, and tolerance to first line TB drugs. VBNC bacteria are reactivatable upon removal of vit C and they recover drug susceptibility properties. Vit C synergizes with pyrazinamide, a unique TB drug with sterilizing activity, to kill dormant and replicating bacteria, negating any tolerance to rifampicin and isoniazid in combination treatment in both in-vitro and intracellular infection models. Finally, the vit C multi-stress redox models described here also offer a unique opportunity for concurrent screening of compounds/combinations active against heterogeneous subpopulations of Mtb. These findings suggest a novel strategy of vit C adjunctive therapy by modulating bacterial physiology for enhanced efficacy of combination chemotherapy with existing drugs, and also possible synergies to guide new therapeutic combinations towards accelerating TB treatment. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Clinical efficiency of applying low-intensity laser therapy in treating dyscirculatory encephalopathy

NASA Astrophysics Data System (ADS)

Putilina, M. V.; Kozlov, V. I.; Vakhtin, V. I.

2001-04-01

An investigation was made of applying laser therapy combined with drug preparations in treating 300 patients affected by dyscirculatory encephalopathy. Neurological and neuropsychological examinations together with electroencephalography, rheoencephalography, computerized tomography, and magnetic resonance imaging were used to assess the patients' states prior to and after the treatment. It was found that the combined application of laser therapy and drug preparations produced a more pronounced therapeutic effect as compared with that produced by the separate application of laser therapy and drug preparations. The results obtained allowed us to conclude that the 0.89 micrometers laser infrared radiation increased patients' susceptibility to drugs. Moreover, the combined laser therapy improved the cerebral bloodflow and activated the metabolic and plastic functions of neurons. This decreased or eliminated late complications provoked by the cerebral blood circulation insufficiency.

Mechanisms of tramadol-related neurotoxicity in the rat: Does diazepam/tramadol combination play a worsening role in overdose?

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

Lagard, Camille, E-mail: camille.lagard@gmail.com

Poisoning with opioid analgesics including tramadol represents a challenge. Tramadol may induce respiratory depression, seizures and serotonin syndrome, possibly worsened when in combination to benzodiazepines. Our objectives were to investigate tramadol-related neurotoxicity, consequences of diazepam/tramadol combination, and mechanisms of drug-drug interactions in rats. Median lethal-doses were determined using Dixon–Bruce's up-and-down method. Sedation, seizures, electroencephalography and plethysmography parameters were studied. Concentrations of tramadol and its metabolites were measured using liquid-chromatography-high-resolution-mass-spectrometry. Plasma, platelet and brain monoamines were measured using liquid-chromatography coupled to fluorimetry. Median lethal-doses of tramadol and diazepam/tramadol combination did not significantly differ, although time-to-death was longer with combination (P =more » 0.04). Tramadol induced dose-dependent sedation (P < 0.05), early-onset seizures (P < 0.001) and increase in inspiratory (P < 0.01) and expiratory times (P < 0.05). The diazepam/tramadol combination abolished seizures but significantly enhanced sedation (P < 0.01) and respiratory depression (P < 0.05) by reducing tidal volume (P < 0.05) in addition to tramadol-related increase in respiratory times, suggesting a pharmacodynamic mechanism of interaction. Plasma M1 and M5 metabolites were mildly increased, contributing additionally to tramadol-related respiratory depression. Tramadol-induced early-onset increase in brain concentrations of serotonin and norepinephrine was not significantly altered by the diazepam/tramadol combination. Interestingly neither pretreatment with cyproheptadine (a serotonin-receptor antagonist) nor a benserazide/5-hydroxytryptophane combination (enhancing brain serotonin) reduced tramadol-induced seizures. Our study shows that diazepam/tramadol combination does not worsen tramadol-induced fatality risk but alters its toxicity pattern with enhanced respiratory depression but abolished seizures. Drug-drug interaction is mainly pharmacodynamic but increased plasma M1 and M5 metabolites may also contribute to enhancing respiratory depression. Tramadol-induced seizures are independent of brain serotonin. - Highlights: • Diazepam does not alter tramadol-induced median lethal dose but delays death onset. • Diazepam/tramadol combination worsens respiratory depression but prevents seizures. • Diazepam/tramadol-induced respiratory effects results from a pharmacodynamic drug-drug interaction. • Tramadol increases brain serotonin and norepinephrine that is not altered by diazepam. • Tramadol-induced seizures are independent of brain serotonin.« less

In vivo and in vitro studies of Cry5B and nicotinic acetylcholine receptor agonist anthelmintics reveal a powerful and unique combination therapy against intestinal nematode parasites.

PubMed

Hu, Yan; Miller, Melanie; Zhang, Bo; Nguyen, Thanh-Thanh; Nielsen, Martin K; Aroian, Raffi V

2018-05-01

The soil-transmitted nematodes (STNs) or helminths (hookworms, whipworms, large roundworms) infect the intestines of ~1.5 billion of the poorest peoples and are leading causes of morbidity worldwide. Only one class of anthelmintic or anti-nematode drugs, the benzimidazoles, is currently used in mass drug administrations, which is a dangerous situation. New anti-nematode drugs are urgently needed. Bacillus thuringiensis crystal protein Cry5B is a powerful, promising new candidate. Drug combinations, when properly made, are ideal for treating infectious diseases. Although there are some clinical trials using drug combinations against STNs, little quantitative and systemic work has been performed to define the characteristics of these combinations in vivo. Working with the hookworm Ancylostoma ceylanicum-hamster infection system, we establish a laboratory paradigm for studying anti-nematode combinations in vivo using Cry5B and the nicotinic acetylcholine receptor (nAChR) agonists tribendimidine and pyrantel pamoate. We demonstrate that Cry5B strongly synergizes in vivo with both tribendimidine and pyrantel at specific dose ratios against hookworm infections. For example, whereas 1 mg/kg Cry5B and 1 mg/kg tribendimidine individually resulted in only a 0%-6% reduction in hookworm burdens, the combination of the two resulted in a 41% reduction (P = 0.020). Furthermore, when mixed at synergistic ratios, these combinations eradicate hookworm infections at doses where the individual doses do not. Using cyathostomin nematode parasites of horses, we find based on inhibitory concentration 50% values that a strongylid parasite population doubly resistant to nAChR agonists and benzimidazoles is more susceptible or "hypersusceptible" to Cry5B than a cyathostomin population not resistant to nAChR agonists, consistent with previous Caenhorhabditis elegans results. Our study provides a powerful means by which anthelmintic combination therapies can be examined in vivo in the laboratory. In addition, we demonstrate that Cry5B and nAChR agonists have excellent combinatorial properties-Cry5B combined with nAChR agonists gives rise to potent cures that are predicted to be recalcitrant to the development of parasite resistance. These drug combinations highlight bright spots in new anthelmintic development for human and veterinary animal intestinal nematode infections.

Evaluation of the cytotoxicity of the Bithionol - cisplatin combination in a panel of human ovarian cancer cell lines.

PubMed

Ayyagari, Vijayalakshmi N; Hsieh, Tsung-Han Jeff; Diaz-Sylvester, Paula L; Brard, Laurent

2017-01-13

Combination drug therapy appears a promising approach to overcome drug resistance and reduce drug-related toxicities in ovarian cancer treatments. In this in vitro study, we evaluated the antitumor efficacy of cisplatin in combination with Bithionol (BT) against a panel of ovarian cancer cell lines with special focus on cisplatin-sensitive and cisplatin-resistant cell lines. The primary objectives of this study are to determine the nature of the interactions between BT and cisplatin and to understand the mechanism(s) of action of BT-cisplatin combination. The cytotoxic effects of drugs either alone or in combination were evaluated using presto-blue assay. Cellular reactive oxygen species were measured by flow cytometry. Immunoblot analysis was carried out to investigate changes in levels of cleaved PARP, XIAP, bcl-2, bcl-xL, p21 and p27. Luminescent and colorimetric assays were used to test caspases 3/7 and ATX activity. The efficacy of the BT-cisplatin combination depends upon the cell type and concentrations of cisplatin and BT. In cisplatin-sensitive cell lines, BT and cisplatin were mostly antagonistic except when used at low concentrations, where synergy was observed. In contrast, in cisplatin-resistant cells, BT-cisplatin combination treatment displayed synergistic effects at most of the drug ratios/concentrations. Our results further revealed that the synergistic interaction was linked to increased reactive oxygen species generation and apoptosis. Enhanced apoptosis was correlated with loss of pro-survival factors (XIAP, bcl-2, bcl-xL), expression of pro-apoptotic markers (caspases 3/7, PARP cleavage) and enhanced cell cycle regulators p21 and p27. In cisplatin-resistant cell lines, BT potentiated cisplatin-induced cytotoxicity at most drug ratios via enhanced ROS generation and modulation of key regulators of apoptosis. Low doses of BT and cisplatin enhanced efficiency of cisplatin treatment in all the ovarian cancer cell lines tested. Our results suggest that novel combinations such as BT and cisplatin might be an attractive therapeutic approach to enhance ovarian cancer chemosensitivity. Combining low doses of cisplatin with subtherapeutic doses of BT can ultimately lead to the development of an innovative combination therapy to reduce/prevent the side effects normally occurring when high doses of cisplatin are administered.

A quantitative benefit-risk assessment approach to improve decision making in drug development: Application of a multicriteria decision analysis model in the development of combination therapy for overactive bladder.

PubMed

de Greef-van der Sandt, I; Newgreen, D; Schaddelee, M; Dorrepaal, C; Martina, R; Ridder, A; van Maanen, R

2016-04-01

A multicriteria decision analysis (MCDA) approach was developed and used to estimate the benefit-risk of solifenacin and mirabegron and their combination in the treatment of overactive bladder (OAB). The objectives were 1) to develop an MCDA tool to compare drug effects in OAB quantitatively, 2) to establish transparency in the evaluation of the benefit-risk profile of various dose combinations, and 3) to quantify the added value of combination use compared to monotherapies. The MCDA model was developed using efficacy, safety, and tolerability attributes and the results of a phase II factorial design combination study were evaluated. Combinations of solifenacin 5 mg and mirabegron 25 mg and mirabegron 50 (5+25 and 5+50) scored the highest clinical utility and supported combination therapy development of solifenacin and mirabegron for phase III clinical development at these dose regimens. This case study underlines the benefit of using a quantitative approach in clinical drug development programs. © 2015 The American Society for Clinical Pharmacology and Therapeutics.

Autoantibodies developing to myeloperoxidase and proteinase 3 in systemic vasculitis stimulate neutrophil cytotoxicity toward cultured endothelial cells.

PubMed Central

Savage, C. O.; Pottinger, B. E.; Gaskin, G.; Pusey, C. D.; Pearson, J. D.

1992-01-01

The ability of vasculitis-associated anti-neutrophil cytoplasm antibodies (ANCA) to activate neutrophils and mediate release of radiolabel from 111Indium-labeled cultured human umbilical vein endothelial cells (HUVEC) was determined as a measure of the potential cytotoxicity of ANCA-activated neutrophils against vascular endothelium. Priming of neutrophils with low doses of phorbol 12-myristate 13-acetate (PMA) (1 ng/ml) and ionomycin (0.1 mumol/1) was required, together with pretreatment of endothelial cells with BCNU (1,3-bis-[2-chloroethyl]-1-nitrosourea; 0.26 mmol/l). Under these conditions and using a 4-hour serum-free assay system, mouse monoclonal antibodies (MAb) to the target autoantigens proteinase-3 (Pr-3) and myeloperoxidase (MPO) mediated enhanced release of 111Indium from HUVEC compared with control MAb. Human IgG Fab2 C-ANCA (recognizing Pr-3) and P-ANCA (recognizing MPO) did likewise. Preactivation of HUVEC with TNF (50 U/ml, 4 hr) enhanced the release of 111Indium from HUVEC generated by neutrophils activated with anti-Pr-3 and anti-MPO MAb. These data support the suggestion that activation of neutrophils by ANCA within the vascular lumen may contribute to endothelial cell injury. PMID:1323218

The individual and combined effects of phenmetrazine and mgluR2/3 agonist LY379268 on the motivation to self-administer cocaine.

PubMed

Karkhanis, Anushree N; Beveridge, Thomas J R; Blough, Bruce E; Jones, Sara R; Ferris, Mark J

2016-09-01

The US Food and Drug Administration has not approved a treatment for cocaine addiction, possibly due in part to the fact that repeated cocaine use results in dysregulation of multiple neurotransmitter systems, including glutamate and dopamine, and an emergence of increased negative affective states and heightening motivation to take cocaine despite negative consequences. We used a combination therapy approach to assess whether modulation of both glutamate and dopamine transmission would reduce the motivation to self- administer cocaine compared to modulation of either system alone. The metabotropic glutamate 2/3 receptor agonist, LY379268, and the monoamine releaser, phenmetrazine, were used to assess their individual and combined ability to decrease the reinforcing efficacy of cocaine because they modulate glutamate and dopamine levels, respectively. Cocaine breakpoints and cocaine intake was assessed, using a progressive ratio schedule, at baseline in three groups based on dose of cocaine (0.19, 0.38, 0.75mg/kg/infusion), and following LY379268 (0.03 or 0.30mg/kg; i.p.), phenmetrazine (25mg/kg/day; osmotic minipump), and a combination of the two drugs. LY379268 and phenmetrazine alone reduced breakpoints for all doses of cocaine. The combination of the two drugs showed a concerted effect in reducing breakpoints for all doses of cocaine, with the lowest dose of cocaine reduced by as much as 70%. These data support combination therapy of dopamine and glutamate systems as an effective means to reduce the motivation to take cocaine since a combination of drugs can address neurobiological dysfunction in multiple neurotransmitter systems compared to therapies using single drugs. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Analysis of the antinociceptive interactions in two-drug combinations of gabapentin, oxcarbazepine and amitriptyline in streptozotocin-induced diabetic mice.

PubMed

Tomić, Maja A; Vucković, Sonja M; Stepanović-Petrović, Radica M; Micov, Ana M; Ugresić, Nenad D; Prostran, Milica S; Bosković, Bogdan

2010-02-25

Antiepileptic and antidepressant drugs are the primary treatments for pain relief in diabetic neuropathy. Combination therapy is a valid approach in pain treatment, where a reduction of doses could reduce side effects and still achieve optimal analgesia. We examined the effects of two-drug combinations of gabapentin, oxcarbazepine, and amitriptyline on nociception in diabetic mice and aimed to determine the type of interaction between components. The nociceptive responses in normal and diabetic mice were assessed by the tail-flick test. The testing was performed before and three weeks after the diabetes induction with streptozotocin (150mg/kg; i.p.), when the antinociceptive effects of gabapentin, oxcarbazepine, amitriptyline and their two-drug combinations were examined. Gabapentin (10-40mg/kg; p.o.) and oxcarbazepine (20-80mg/kg; p.o.) produced a significant, dose-dependent antinociception in diabetic mice while amitriptyline (5-60mg/kg; p.o.) produced weak antinociceptive effect. In normal mice, neither of the drugs produced antinociception. Gabapentin and oxcarbazepine, co-administered in fixed-dose fractions of the ED(50) to diabetic mice, induced significant, dose-dependent antinociception. Isobolographic analysis revealed synergistic interaction. Oxcarbazepine (10-60mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) and gabapentin (10-30mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) combinations significantly and dose-dependently reduced nociception in diabetic mice. Analysis of the log dose-response curves for oxcarbazepine or gabapentin in a presence of amitriptyline and oxcarbazepine or gabapentin applied alone, revealed a synergism in oxcarbazepine-amitriptyline and additivity in gabapentin-amitriptyline combination. These findings provide new information about the combination therapy of painful diabetic neuropathy and should be explored further in patients with diabetic neuropathy.

In vitro and in vivo drug combination for the treatment of Trypanosoma cruzi infection: A multivariate approach.

PubMed

Strauss, Mariana; Rodrigues, Jean Henrique S; Lo Presti, María Silvina; Bazán, Paola Carolina; Báez, Alejandra Lidia; Paglini-Oliva, Patricia; Nakamura, Celso Vataru; Bustamante, Juan Manuel; Rivarola, Héctor Walter

2018-06-01

Combination therapies based on the available drugs have been proposed as promising therapeutic alternatives for many diseases. Clomipramine (CLO) has been found to modify the evolution of the experimental infection. The objective of this study was to evaluate the combined effect of benznidazole (BZ) and clomipramine (CLO) against different life-stages of Trypanosoma cruzi in vitro and their efficacy in a murine model. Life-stages of T. cruzi, BZ-partially-resistant (Y) strain, were incubated with BZ and CLO and isobolograms and combination index (CI) were obtained. Swiss mice were infected with trypomastigotes and different treatment schedules were performed, each of which consisted of 30 consecutive daily doses. Treatment efficacy was evaluated by comparing parasitemia, qPCR, survival and histological analysis. These results were analyzed using multivariate analysis to determine the combined effect of the drugs in vivo. CLO + BZ showed synergistic activity in vitro against the clinically relevant life-stages of T. cruzi. The most susceptible forms were the intracellular amastigotes (CI: 0.20), followed by trypomastigotes (CI: 0.60), with no toxicity upon mammalian cells. The combination of both drugs CLO (1.25 mg/kg) and BZ (6.25 mg/kg), in vivo, significantly diminished the parasitic load in blood and the mortality rate. CLO + BZ presented a similar inflammatory response in cardiac and skeletal muscle (amount of inflammatory cells) to BZ (6.25 mg/kg). Finally, the results from the principal component analysis reaffirmed that both drugs administered in combination presented higher activity compared with the individual administration in the acute experimental model. Copyright © 2018 Elsevier Inc. All rights reserved.

Epigenetic polypharmacology: from combination therapy to multitargeted drugs.

PubMed

de Lera, Angel R; Ganesan, A

The modern drug discovery process has largely focused its attention in the so-called magic bullets, single chemical entities that exhibit high selectivity and potency for a particular target. This approach was based on the assumption that the deregulation of a protein was causally linked to a disease state, and the pharmacological intervention through inhibition of the deregulated target was able to restore normal cell function. However, the use of cocktails or multicomponent drugs to address several targets simultaneously is also popular to treat multifactorial diseases such as cancer and neurological disorders. We review the state of the art with such combinations that have an epigenetic target as one of their mechanisms of action. Epigenetic drug discovery is a rapidly advancing field, and drugs targeting epigenetic enzymes are in the clinic for the treatment of hematological cancers. Approved and experimental epigenetic drugs are undergoing clinical trials in combination with other therapeutic agents via fused or linked pharmacophores in order to benefit from synergistic effects of polypharmacology. In addition, ligands are being discovered which, as single chemical entities, are able to modulate multiple epigenetic targets simultaneously (multitarget epigenetic drugs). These multiple ligands should in principle have a lower risk of drug-drug interactions and drug resistance compared to cocktails or multicomponent drugs. This new generation may rival the so-called magic bullets in the treatment of diseases that arise as a consequence of the deregulation of multiple signaling pathways provided the challenge of optimization of the activities shown by the pharmacophores with the different targets is addressed.

Effects of ionizing radiation in combination with Erufosine on T98G glioblastoma xenograft tumours: a study in NMRI nu/nu mice.

PubMed

Henke, Guido; Meier, Verena; Lindner, Lars H; Eibl, Hansjörg; Bamberg, Michael; Belka, Claus; Budach, Wilfried; Jendrossek, Verena

2012-10-18

Erufosine is a promising anticancer drug that increases the efficacy of radiotherapy in glioblastoma cell lines in vitro. Moreover, treatment of nude mice with repeated intraperitoneal or subcutaneous injections of Erufosine is well tolerated and yields drug concentrations in the brain tissue that are higher than the concentrations required for cytotoxic drug effects on glioblastoma cell lines in vitro. In the present study we aimed to evaluate the effects of a combined treatment with radiotherapy and Erufosine on growth and local control of T98G subcutaneous glioblastoma xenograft-tumours in NMRI nu/nu mice. We show that repeated intraperitoneal injections of Erufosine resulted in a significant drug accumulation in T98G xenograft tumours on NMRI nu/nu mice. Moreover, short-term treatment with 5 intraperitoneal Erufosine injections caused a transient decrease in the growth of T98G tumours without radiotherapy. Furthermore, an increased radiation-induced growth delay of T98G xenograft tumours was observed when fractionated irradiation was combined with short-term Erufosine-treatment. However, no beneficial drug effects on fractionated radiotherapy in terms of local tumour control were observed. We conclude that short-term treatment with Erufosine is not sufficient to significantly improve local control in combination with radiotherapy in T98G glioblastoma xenograft tumours. Further studies are needed to evaluate efficacy of extended drug treatment schedules.

AFM combined to ATR-FTIR reveals Candida cell wall changes under caspofungin treatment.

PubMed

Quilès, Fabienne; Accoceberry, Isabelle; Couzigou, Célia; Francius, Grégory; Noël, Thierry; El-Kirat-Chatel, Sofiane

2017-09-21

Fungal pathogens from Candida genus are responsible for severe life-threatening infections and the antifungal arsenal is still limited. Caspofungin, an antifungal drug used for human therapy, acts as a blocking agent of the cell wall synthesis by inhibiting the β-1,3-glucan-synthase encoded by FKS genes. Despite its efficiency, the number of genetic mutants that are resistant to caspofungin is increasing. An important challenge to improve antifungal therapy is to understand cellular phenomenon that are associated with drug resistance. Here we used atomic force microscopy (AFM) combined to Fourier transform infrared spectroscopy in attenuated total reflection mode (ATR-FTIR) to decipher the effect of low and high drug concentration on the morphology, mechanics and cell wall composition of two Candida strains, one susceptible and one resistant to caspofungin. Our results confirm that caspofungin induces a dramatic cell wall remodelling via activation of stress responses, even at high drug concentration. Additionally, we highlighted unexpected changes related to drug resistance, suggesting that caspofungin resistance associated with FKS gene mutations comes from a combination of effects: (i) an overall remodelling of yeast cell wall composition; and (ii) cell wall stiffening through chitin synthesis. This work demonstrates that AFM combined to ATR-FTIR is a valuable approach to understand at the molecular scale the biological mechanisms associated with drug resistance.

Myricetin and methyl eugenol combination enhances the anticancer activity, cell cycle arrest and apoptosis induction of cis-platin against HeLa cervical cancer cell lines

PubMed Central

Yi, Jin-Ling; Shi, Song; Shen, Yan-Li; Wang, Ling; Chen, Hai-Yan; Zhu, Jun; Ding, Yan

2015-01-01

Drug combination therapies are common practice in the treatment of cancer. In this study, we evaluated the anticancer effects of myricetin (MYR), methyl eugenol (MEG) and cisplatin (CP) both separately as well as in combination against cervical cancer (HeLa) cells. To demonstrate whether MYR and MEG enhance the anticancer activity of CP against cervical cancer cells, we treated HeLa cells with MYR and MEG alone or in combination with cisplatin and evaluated cell growth and apoptosis using MTT (3 (4, 5 dimethyl thiazol 2yl) 2, 5 diphenyltetrazolium bromide) assay, LDH release assay, flow cytometry and fluorescence microscopy. The results revealed that, as compared to single drug treatment, the combination of MYR or MEG with CP resulted in greater effect in inhibiting cancer cell growth and inducing apoptosis. Cell apoptosis induction, Caspase-3 activity, cell cycle arrest and mitochondrial membrane potential loss were systematically studied to reveal the mechanisms of synergy between MYR, MEG and CP. Combination of MYR or MEG with CP resulted in more potent apoptosis induction as revealed by fluorescence microscopy using Hoechst 33258 and AO-ETBR staining. The combination treatment also increased the number of cells in G0/G1 phase dramatically as compared to single drug treatment. Mitochondrial membrane potential loss (ΛΨm) as well as Caspase-3 activity was much higher in combination treatment as compared to single drug treatment. Findings of this investigation suggest that MYR and MEG combined with cisplatin is a potential clinical chemotherapeutic approach in human cervical cancer. PMID:25972998

Additive naftopidil treatment synergizes docetaxel-induced apoptosis in human prostate cancer cells.

PubMed

Ishii, Kenichiro; Matsuoka, Izumi; Kajiwara, Shinya; Sasaki, Takeshi; Miki, Manabu; Kato, Manabu; Kanda, Hideki; Arima, Kiminobu; Shiraishi, Taizo; Sugimura, Yoshiki

2018-01-01

Docetaxel (DTX) is a standard chemotherapeutic drug for castration-resistant prostate cancer (CRPC), although adverse events are common. To overcome this problem, researchers have evaluated the efficacy of DTX treatment in combination with other drugs. Naftopidil is a tubulin-binding drug with fewer adverse events, implying the usefulness of this drug in clinical applications when combined with DTX. Here, we investigated the efficacy of additive naftopidil treatment in combination with DTX on prostate cancer (PCa) cells. The effects of combination treatment with DTX plus naftopidil were analyzed using two animal models of LNCaP cells plus PrSC xenografts (sub-renal capsule grafting) and PC-3 xenografts (intratibial injection). Combination treatment with DTX plus naftopidil significantly inhibited cell growth in LNCaP cells compared with DTX alone. Analysis of the cooperativity index (CI) showed that combination treatment exhibited additive effects on DTX-induced growth inhibition in LNCaP cells. In contrast, combination treatment showed more than an additive (synergistic) effect on DTX-induced apoptosis in LNCaP and PC-3 cells. In LNCaP cells plus PrSC xenografts, combination treatment showed synergistic effects on DTX-induced apoptosis. The synergistic effects of naftopidil on DTX-induced apoptosis were also observed in PC-3 xenografts. Our results demonstrated that additive naftopidil treatment in combination with DTX increased the efficacy of DTX for the treatment of LNCaP and PC-3 tumors in vivo. Thus, additive naftopidil treatment showed a synergistic effect on DTX-induced apoptosis in PCa cells in vitro and in vivo, suggesting that this treatment approach may yield improved clinical benefits compared with DTX alone.

Drug–drug interactions between antithrombotic medications and the risk of gastrointestinal bleeding

PubMed Central

Delaney, Joseph A.; Opatrny, Lucie; Brophy, James M.; Suissa, Samy

2007-01-01

Background Anticoagulants and antiplatelet drugs (e.g., warfarin, clopidogrel and acetylsalicylic acid) are key therapeutic agents in the treatment of cardiovascular diseases. However, drug–drug interactions may lead to a greatly increased risk of gastrointestinal bleeding when these drugs are combined. We assessed whether antithrombotic drug combinations increased the risk of such bleeding in a general practice population. Methods We conducted a population-based, retrospective case–control study using records in the United Kingdom General Practice Research Database from 2000 through 2005. Cases were identified as patients over 18 years of age with a first-ever diagnosis of gastrointestinal bleeding. They were matched with controls by physician practice, patient age and index date (date of diagnosis of bleeding). All eligible patients had to have at least 3 years of follow-up data in the database. Drug exposure was considered to be any prescription issued in the 90 days before the index date. Results There were 4028 cases with a diagnosis of gastrointestinal bleeding and 40 171 matched controls. The prescribing of acetylsalicylic acid with either clopidogrel (adjusted rate ratio [RR] 3.90, 95% confidence interval [CI] 2.78–5.47) or warfarin (adjusted RR 6.48, 95% CI 4.25–9.87) was associated with a greater risk of gastrointestinal bleeding than that observed with each drug alone. The same was true when a nonsteroidal anti-inflammatory drug was combined with either clopidogrel (adjusted RR 2.93, 95% CI 1.74–4.93) or warfarin (RR 4.60, 95% CI 2.77–7.64). Interpretation Drug combinations involving antiplatelets and anticoagulants are associated with a high risk of gastrointestinal bleeding beyond that associated with each drug used alone. Physicians should be aware of these risks to better assess their patients' therapeutic risk–benefit profiles. PMID:17698822

Partnership to Explore New Drug Combination for Pancreatic Cancer | Poster

Cancer.gov

By Frank Blanchard, Staff Writer Scientists at NCI and Frederick National Laboratory for Cancer Research (FNLCR) are partnering with the Lustgarten Foundation to test whether a vitamin D derivative will make a difference when combined with a conventional anticancer drug in treating tumors of the pancreas.

New clinical trial studies drug combination for recurring ovarian cancer | Center for Cancer Research

Cancer.gov

A new clinical trial is studying the effectiveness of an investigational drug combination that looks to see whether reducing the supply of oxygen to the cancer cells can make ovarian cancer shrink or slow its growth in association with an enzyme that repairs DNA damage.

Formulation and Characterization of Solid Dispersion Prepared by Hot Melt Mixing: A Fast Screening Approach for Polymer Selection

PubMed Central

Enose, Arno A.; Dasan, Priya K.; Sivaramakrishnan, H.; Shah, Sanket M.

2014-01-01

Solid dispersion is molecular dispersion of drug in a polymer matrix which leads to improved solubility and hence better bioavailability. Solvent evaporation technique was employed to prepare films of different combinations of polymers, plasticizer, and a modal drug sulindac to narrow down on a few polymer-plasticizer-sulindac combinations. The sulindac-polymer-plasticizer combination that was stable with good film forming properties was processed by hot melt mixing, a technique close to hot melt extrusion, to predict its behavior in a hot melt extrusion process. Hot melt mixing is not a substitute to hot melt extrusion but is an aid in predicting the formation of molecularly dispersed form of a given set of drug-polymer-plasticizer combination in a hot melt extrusion process. The formulations were characterized by advanced techniques like optical microscopy, differential scanning calorimetry, hot stage microscopy, dynamic vapor sorption, and X-ray diffraction. Subsequently, the best drug-polymer-plasticizer combination obtained by hot melt mixing was subjected to hot melt extrusion process to validate the usefulness of hot melt mixing as a predictive tool in hot melt extrusion process. PMID:26556187

In vitro activities of ciprofloxacin and rifampin alone and in combination against growing and nongrowing strains of methicillin-susceptible and methicillin-resistant Staphylococcus aureus.

PubMed Central

Bahl, D; Miller, D A; Leviton, I; Gialanella, P; Wolin, M J; Liu, W; Perkins, R; Miller, M H

1997-01-01

We characterized the effects of ciprofloxacin and rifampin alone and in combination on Staphylococcus aureus in vitro. The effects of drug combinations (e.g., indifferent, antagonistic, or additive interactions) on growth inhibition were compared by disk approximation studies and by determining the fractional inhibitory concentrations. Bactericidal effects in log-phase bacteria and in nongrowing isolates were characterized by time-kill methods. The effect of drug combinations was dependent upon whether or not cells were growing and whether killing or growth inhibition was the endpoint used to measure drug interaction. Despite bactericidal antagonism in time-kill experiments, our in vitro studies suggest several possible explanations for the observed benefits in patients treated with a combination of ciprofloxacin and rifampin for deep-seated staphylococcal infections. Notably, when growth inhibition rather than killing was used to characterize drug interaction, indifference rather than antagonism was observed. An additive bactericidal effect was observed in nongrowing bacteria suspended in phosphate-buffered saline. While rifampin antagonized the bactericidal effects of ciprofloxacin, ciprofloxacin did not antagonize the bactericidal effects of rifampin. Each antimicrobial prevented the emergence of subpopulations that were resistant to the other. PMID:9174186

Sonochemotherapy: from bench to bedside

PubMed Central

Lammertink, Bart H. A.; Bos, Clemens; Deckers, Roel; Storm, Gert; Moonen, Chrit T. W.; Escoffre, Jean-Michel

2015-01-01

The combination of microbubbles and ultrasound has emerged as a promising method for local drug delivery. Microbubbles can be locally activated by a targeted ultrasound beam, which can result in several bio-effects. For drug delivery, microbubble-assisted ultrasound is used to increase vascular- and plasma membrane permeability for facilitating drug extravasation and the cellular uptake of drugs in the treated region, respectively. In the case of drug-loaded microbubbles, these two mechanisms can be combined with local release of the drug following destruction of the microbubble. The use of microbubble-assisted ultrasound to deliver chemotherapeutic agents is also referred to as sonochemotherapy. In this review, the basic principles of sonochemotherapy are discussed, including aspects such as the type of (drug-loaded) microbubbles used, the routes of administration used in vivo, ultrasound devices and parameters, treatment schedules and safety issues. Finally, the clinical translation of sonochemotherapy is discussed, including the first clinical study using sonochemotherapy. PMID:26217226