Improving adherence to daily preexposure prophylaxis among MSM in Amsterdam by providing feedback via a mobile application

OBJECTIVE: Improving adherence to preexposure prophylaxis (PrEP) by providing automated feedback on self-reported PrEP use via a mobile application (app). DESIGN: Randomized clinical trial among MSM participating in the Amsterdam PrEP demonstration project (AMPrEP). METHODS: Eligible participants were randomized 1 : 1 to the control or intervention app. Both allowed daily reporting of sexual behaviour and medication intake; the intervention app also provided visual feedback. Dried blood spots collected at 12 and 24 months yielded intracellular tenofovir diphosphate concentrations (TFV-DP). We assessed proportions of participants with poor (TFV-DP <700 fmol/punch; primary outcome), good (TFV-DP ≥700 fmol/punch) and excellent (TFV-DP ≥1250 fmol/punch; secondary outcome) adherence at both time-points, and the association with the control or intervention app. RESULTS: We randomized 229 participants, 118 to the intervention and 111 to the control arm. The primary, per-protocol, analysis included 83 participants per arm. In total, 22/166 (13%) of participants adhered poorly, 144/166 (87%) good and 66/166 (40%) excellently. App feedback did not result in a lower proportion of participants with poor adherence [control: 9 of 83 (11%); intervention: 13 of 83 (16%); P = 0.36]. App feedback did result in a larger proportion of participants with excellent adherence [control: 26/83 (31%); intervention: 40/83 (48%); P = 0.026]. CONCLUSION: In this highly adherent population, app feedback did not improve the proportion of participants with poor adherence to PrEP.Clinical Trial Number Netherlands Trial Register: NL5413.