Optimal HIV Postexposure Prophylaxis Regimen Completion With Single Tablet Daily Elvitegravir/Cobicistat/Tenofovir Disoproxil Fumarate/Emtricitabine Compared With More Frequent Dosing Regimens.

STRUCTURE: The study evaluated elvitegravir/cobicistat/tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) ("Quad pill") for postexposure prophylaxis (PEP).
BACKGROUND: HIV-exposed individuals may benefit from PEP, but completion rates have been suboptimal because of regimen complexity and side effects. Newer antiretroviral combinations coformulated as single daily pills may optimize PEP adherence.
SETTING: One hundred HIV-uninfected individuals who presented to a Boston community health center after an acute HIV sexual exposure were enrolled and initiated PEP with the daily, single-pill combination Quad pill for a 28-day course.
METHODS: Side effects and medication completion rates from study participants were compared with historical controls who had used PEP regimens consisting of TDF/FTC daily and raltegravir twice daily, or earlier regimens of twice daily zidovudine (AZT)/lamivudine (3TC) and a protease inhibitor, using χ tests for independence.
RESULTS: Of the 100 participants who initiated the Quad pill for PEP after a high-risk sexual exposure, 71% completed the 28-day Quad pill regimen, which was significantly greater than historical controls who used TDF/FTC and raltegravir (57%, P < 0.05) or AZT/3TC plus a protease inhibitor (39%, P < 0.001). The most common side effects reported by Quad pill users were as follows: abdominal discomfort or pain, gas or bloating (42%), diarrhea (38%), fatigue (28%), nausea or vomiting (28%), headache (14%), or dizziness or lightheadedness (6%). Most symptoms were mild, limited, and did not result in medication discontinuation. No participants became HIV infected.
CONCLUSIONS: Fixed-dose combination of elvitegravir/cobicistat/TDF/FTC was safe and well tolerated for PEP, with higher regimen completion rates than more frequently dosed PEP regimens.