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).