The use of antiretrovirals for post-exposure prophylaxis (PEP) is well-established, although completion rates with prior regimens have been suboptimal because of pill burden or side effects. The purpose of the current study has been to evaluate the single tablet regimen of of bictegravir, emtricitabine, tenofovir alafenamide (BIC/FTC/TAF) for PEP, administered daily for 28 days after a high risk exposure.
The analyses focused on a prospectively enrolled clinical cohort recruited through referrals from a busy medical department in a Boston community health center, specialized in HIV care, as well as from a community education campaign.
Of the first 39 enrollees, the median age was 33 years (range 22-71), with 12.8% Black and 5.1% Latinx. Most (76.9%) were cisgender gay or bisexual men. Other participants included 3 heterosexual cisgender men, 1 transgender woman and 2 cisgender women. Most (76.9%) completed college +/- advanced degrees. Behaviors that led to PEP initiation included: receptive anal (49.7%), insertive anal (43.6%), receptive oral (15.4%), and insertive or receptive vaginal sex (7.7% for each). The most commonly reported adverse events were nausea +/- vomiting (12.8%), fatigue (10.3%), and diarrhea (10.3%). One participant noted mild gastrointestinal discomfort and another reported flatulence. All but one of the symptoms were grade 1; a grade 2 report of fatigue led to product discontinuation. The only lab abnormalities were elevated transaminases (N=2) and decreased creatinine clearance (N=1). These changes did not lead to product discontinuation, and reverted after regimen completion. Of the 39 fully evaluable participants, 92.3% completed the regimen as prescribed; 2 did not return for follow-up, and one participant discontinued prematurely. No HIV seroconversions have been detected in the study.
The fixed drug combination of bictegravir, emtricitabine, tenofovir alafenamide appears to be safe and well-tolerated when used as PEP, with occasional, mainly mild, gastrointestinal side effects, fatigue, and infrequent laboratory abnormalities. This favorable safety profile, and the high completion rates, suggest that BIC/FTC/TAF is a potential option for PEP.