Safety and Tolerability of Once Daily Coformulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide for Postexposure Prophylaxis After Sexual Exposure

Kenneth H. Mayer, MD; Marcy Gelman, NP; Johnathon Holmes, NP; Jessica Kraft, NP; Kathleen Melbourne, PharmD; Matthew J. Mimiaga, ScD, MPH


J Acquir Immune Defic Syndr. 2022;90(1):27-32. 

In This Article


The study was a single site, investigator-initiated, open-label Phase IV trial to evaluate the safety, tolerability, and acceptability of the fixed dose combination of BIC/FTC/TAF as PEP for individuals who may have been exposed to HIV when they engaged in condomless intercourse. Participants who believed they were recently exposed to HIV were recruited through referrals from primary care providers and a hot line in a Boston community health center specializing in HIV and PEP care, and via self-referral after an online and in-person community education campaign. Eligible participants needed to present for PEP within 72 hours of a high-risk exposure per 2016 Centers for disease control and prevention PEP Guidelines,[21] and be willing to consent to the trial, and prospective monitoring over the subsequent 3-month period. Participants were screened for acute HIV infection by a trained clinician and for prior HIV infection using an HIV rapid test; individuals found to be HIV-positive were referred for HIV primary care. Blood was also collected to test for HIV via a fourth generation antigen–antibody assay, and renal and hepatic function, and to screen for hepatitis B infection. Individuals who were found to be seronegative for hepatitis B were offered vaccination. PEP initiation was not delayed while these assays were performed. Participants were provided with a 28-day regimen of BIC/FTC/TAF, and instructed to take one pill daily. Participants were asked to contact site staff in the event they experienced any adverse events of concern and/or those that would lead them to discontinue study medication. Participants were seen at the study site at 2 weeks and 4 weeks to assess their clinical experience with the regimen, and offered on-site HIV antibody testing at 4 weeks and at 3 months. Side effects and regimen acceptability information were elicited using a standardized interview guide, relying on participant self-report.

SAS 9.4 (SAS Institute, Cary, NC) was used to analyze data, where statistical significance was determined at the 0.05 alpha level.[22] Pearson's χ2 and Fisher's exact tests were conducted to assess whether BIC/FTC/TAF differed with respect to side effects and regimen completion rates compared to historical PEP regimens, which included participants who received regimens that contained zidovudine and protease inhibitors, and participants in 2 earlier phase IV studies of FTC/TDF plus twice daily raltegravir, and the coformulation of elvitegravir, cobicistat, FTC, and TDF.[11,12,20]

The study was reviewed and approved by the institutional review board at the Fenway Institute, Fenway Health and was registered in as NCT03499483.