Feasibility and Acceptability of Digital Pills to Monitor PrEP Adherence in MSM With Substance Use

Eligible study participants will be screened and enrolled at Fenway Health (Boston, MA). Participants will complete a quantitative assessment on their history fo substance use, sexual risk and PrEP adherence, and be trained to use the digital pill for 90 days and instructed to take PrEP daily during the course of the study. Participants will return each month for a study visit to assess their use of the technology. At study visit 1 and 3, we will obtain dried blood spots (DBS) to measure drug levels and to confirm adherence detected by the digital pill. The investigators will also obtain drugs of abuse screens from DBS. At the final study visit (3 months), participants will undergo a semi-structured qualitative interview to understand the user response to digital pills.