Development of Ingestible Biosensors to Enhance PrEP Adherence in Substance Users (PrEPSteps)

Smartphone-based adherence intervention based in 1) LifeSteps, 2) Contingent Reinforcement/Corrective Feedback, and 3) Screening Brief Intervention and Referral to Treatment (SBIRT).

The digital pill comprises a standard gelatin capsule with an integrated radiofrequency emitter that overencapsulates the desired medication (Truvada). When participants ingest the digital pill, the chloride ion gradient in the stomach activates the radiofrequency emitter which transmits direct evidence of medication ingestion to a wearable reader which relays this data to the participant's smartphone and cloud server.

Participants receive once daily Truvada as PrEP to prevent HIV.