The triple combination of tenofovir, emtricitabine and efavirenz shows synergistic anti-HIV-1 activity in vitro: a mechanism of action study

<p>Abstract</p> <p>Background</p> <p>Tenofovir disoproxil fumarate (TDF), emtricitabine (FTC), and efavirenz (EFV) are the three components of the once-daily, single tablet regimen (Atripla) for treatment of HIV-1 infection. Previous cell culture studies have demonstrated that the double combination of tenofovir (TFV), the parent drug of TDF, and FTC were additive to synergistic in their anti-HIV activity, which correlated with increased levels of intracellular phosphorylation of both compounds.</p> <p>Results</p> <p>In this study, we demonstrated the combinations of TFV+FTC, TFV+EFV, FTC+EFV, and TFV+FTC+EFV synergistically inhibit HIV replication in cell culture and synergistically inhibit HIV-1 reverse transcriptase (RT) catalyzed DNA synthesis in biochemical assays. Several different methods were applied to define synergy including median-effect analysis, MacSynergy^®II and quantitative isobologram analysis. We demonstrated that the enhanced formation of dead-end complexes (DEC) by HIV-1 RT and TFV-terminated DNA in the presence of FTC-triphosphate (TP) could contribute to the synergy observed for the combination of TFV+FTC, possibly through reduced terminal NRTI excision. Furthermore, we showed that EFV facilitated efficient formation of stable, DEC-like complexes by TFV- or FTC-monophosphate (MP)-terminated DNA and this can contribute to the synergistic inhibition of HIV-1 RT by TFV-diphosphate (DP)+EFV and FTC-TP+EFV combinations.</p> <p>Conclusion</p> <p>This study demonstrated a clear correlation between the synergistic antiviral activities of TFV+FTC, TFV+EFV, FTC+EFV, and TFV+FTC+EFV combinations and synergistic HIV-1 RT inhibition at the enzymatic level. We propose the molecular mechanisms for the TFV+FTC+EFV synergy to be a combination of increased levels of the active metabolites TFV-DP and FTC-TP and enhanced DEC formation by a chain-terminated DNA and HIV-1 RT in the presence of the second and the third drug in the combination. This study furthers the understanding of the longstanding observations of synergistic anti-HIV-1 effects of many NRTI+NNRTI and certain NRTI+NRTI combinations in cell culture, and provides biochemical evidence that combinations of anti-HIV agents can increase the intracellular drug efficacy, without increasing the extracellular drug concentrations.</p

Getting on the Same Page Using Scenario-Based Learning: An Alignment of Education and Industry Goals for Technician Education

This 42-page report is provided by SRI International and examines the results of a scenario-based alignment study. &quot;The current report examines the alignment of a set of scenario-based learning materials with two sets of relevant industry standards. This review deepens knowledge about the range and types of knowledge and skills that scenario-based materials have the potential to address.&quot; In this report, the materials relate to the field of bioinformatics. This report includes a table of contents and the following sections: Executive Summary, Introduction and Background, Findings, Summary and Discussion, References, and Appendices. The Introduction and Background section includes the following subsections: Project Context, Destination SBL Project, SBL-Bioinformatics Instructional and Assessment Materials, Research Questions, Methodology, Sample, Face-to-Face Panel, Online Panel, and Analysis.Â

Implementation of a Multisite Financial Reimbursement Program in Cancer Clinical Trials Integrated With Patient Navigation: A Pilot Randomized Clinical Trial

PurposeCancer clinical trial participants face considerable indirect costs associated with participation, such as travel and lodging, which may contribute to poor enrollment. Here, we report the findings in IMproving Patient Access to Cancer clinical Trials, a pilot feasibility study investigating the efficacy of offering a financial reimbursement program (FRP) during a therapeutic clinical trial discussion with or without additional outreach in improving patient enrollment.MethodsStudy participants for this study were recruited at two National Cancer Institute-designated comprehensive cancer centers (CCCs) from April 8, 2019, to September 19, 2019. Eligible participants were adults with a cancer diagnosis being approached to consider enrollment in a clinical trial. Participants were randomly assigned 1:1 to receive no follow-up (usual care) or a follow-up telephone call to facilitate FRP utilization stratified by study site. The target enrollment was 132 patients, with 66 patients in each study arm. The primary outcome was the consent rate to the multisite interventional study on the FRP among participants enrolling in clinical trials.ResultsThe study had a 78% consent rate and enrolled a total of 132 participants, of whom 51% were non-White compared with 28% of CCC treatment clinical trial participants in 2019. No difference in enrollment in clinical trials between the two study arms was observed as the proportion of enrollment was 70% for both study arms. The most common reason for not enrolling in a clinical trial was due to ineligibility determined through screening procedures (75%).ConclusionThe current study observed that implementation of FRP at CCCs is feasible and serves a diverse patient population. Future studies will measure the impact of programs on overall clinical trial accrual and among racial/ethnic minorities