HIV Pre-exposure Prophylaxis Persistence and Adherence Among Men Who Have Sex With Men in Four US Cities.

Background: HIV pre-exposure prophylaxis (PrEP) persistence and adherence are critical to ending the HIV epidemic in the United States.

Setting: In 2017 National HIV Behavioral Surveillance, HIV-negative men who have sex with men (MSM) in 4 US cities completed a survey, HIV testing, and dried blood spots at recruitment.

Methods: We assessed 3 PrEP outcomes: persistence (self-reported PrEP use at any time in the past 12 months and had tenofovir, emtricitabine, or tenofovir diphosphate detected in dried blood spots), adherence at ≥4 doses/week (self-reported past-month PrEP use and tenofovir diphosphate concentration ≥700 fmol/punch), and adherence at 7 doses/week (self-reported past-month PrEP use and tenofovir diphosphate concentration ≥1250 fmol/punch). Associations with key characteristics were examined using log-linked Poisson regression models with generalized estimating equations.

Results: Among 391 MSM who took PrEP in the past year, persistence was 80% and was lower among MSM who were younger, had lower education, and had fewer sex partners. Of 302 MSM who took PrEP in the past month, adherence at ≥4 doses/week was 80% and adherence at 7 doses/week was 66%. Adherence was lower among MSM who were younger, were Black, and had fewer sex partners.

Conclusions: Although persistence and adherence among MSM were high, 1 in 5 past-year PrEP users were not persistent and 1 in 5 past-month PrEP users were not adherent at levels that would effectively protect them from acquiring HIV (ie, ≥4 doses/week). Efforts to support PrEP persistence and adherence should include MSM who are young, are Black, and have less education.