Antiretroviral Therapy (ART) Persistence in Different Body Compartments in HIV Negative MSM

Men who have sex with men (MSM) continue to be disproportionately affected by HIV. The majority of MSM acquire HIV after exposure to the rectal mucosa through receptive anal intercourse without condoms. Pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) are recommended for MSM who may be exposed to HIV to prevent infection. Current recommendations for PrEP are to take the combination anti-HIV drug, tenofovir+emtricitabine (TDF/FTC), on a daily basis for the duration of someone's HIV risk exposure period, which could be months or years. For PEP, a three-drug anti-HIV medication is recommended within 72 hours of a possible exposure for a 28-day course. While PrEP and PEP are effective, some people find it difficult to follow the recommended regimen. Therefore, additional short-course dosing regimens for PrEP and PEP are being considered for future development. The study drug provided in this study will not protect participants from HIV or treat any active infection. This proposal seeks to understand how other anti-HIV medications are absorbed and how long they persist in different body compartments, including mucosal tissues, as they may be considered for PrEP or PEP regimens in the future. Participants will be sequentially enrolled into study arms. All participants will take two doses of Biktarvy and then will have biological samples collected at different time points. Blood will be collected at three different time points and a rectal biopsy will occur once. Participants may participate in more than one study arm or subgroup; however, at least 6 weeks must lapse after completion of one study arm or subgroup, before entry into another. Median drug levels of TAF, FTC, and BIC in plasma, peripheral blood mononuclear cells (PBMCs) and rectal tissues will be calculated at baseline, 24 hours after the first dose and 120 hours after the first dose as the primary outcomes of this study. Samples collected at other time points will be stored for future exploratory analyses.