Background
PrEP adherence and persistence are suboptimal in real-world settings, with half to two thirds of PrEP users discontinuing within 6 months. We describe results of a comparative effectiveness trial of two mobile health technologies to support PrEP use among MSM and transgender people in the US.
Methods
HIV-uninfected MSM and trans people were enrolled across 3 real-world PrEP delivery sites (a sexual health clinic in San Francisco, a municipal STD clinic in Miami, and an LGBT health center in Washington DC). Participants were randomized 1:1 to receive PrEPmate, a bidirectional texting platform using personalized communication through weekly check-in messages or DOT Diary, a mobile app promoting self-management of PrEP use through a pill-taking/sexual diary with feedback on PrEP protection levels (Figure). PrEP persistence was measured as having sufficient PrEP medication prescribed through 6 months, and PrEP adherence was measured by self-report at 6 months and having protective tenofovir diphosphate (TFV-DP) levels ≥700 fmol/punch in dried blood spots collected at 6 and 12 months (preliminary results available in a subset (n=61)). Effects of treatment assignment on PrEP outcomes were assessed using mixed effects logistic models.
Results
From 7/2021-1/2024, we enrolled 296 participants. Mean age was 30.5 (IQR 26-37), 55% were Hispanic/Latinx, 16% African American; 91% were cisgender male, 9% identified as trans/non-binary; 31% were un-insured, 34% reported limited/marginal health literacy, and 39% were newly starting PrEP. The median number of sex partners in the past 3 months was 5; 55% reported recreational drug use; and 34% reported heavy alcohol use. PrEP persistence at 6 months was 77% in the PrEPmate vs. 78% in the DOT Diary arms (OR 0.92 95% CI 0.53-1.59, p=0.77). Median self-reported adherence was 90% in both arms (p=0.44). Protective TFV-DP was observed in 56% vs. 76% of samples in the PrEPmate vs. DOT Diary arms (p=0.17) (all on daily oral TDF/FTC). Acceptability of both tools was high, with >70% reporting they would use PrEPmate or DOT Diary in the future, and >75% would recommend them to friend.
Conclusions
In this diverse, sexually active cohort, over three-quarters of participants were persistent on PrEP at 6 months, with similar rates across arms. Self-reported adherence was high in both groups, with a preliminary trend towards higher protective TFV-DP in the DOT Diary arm. These data provide evidence for these tools to support PrEP use in real-world settings.