Clinical Research Directory

Inclusion Criteria: * Age 18 years or older * Cisgender-male who reports sex with persons assigned male at birth * Willing and able to provide written informed consent * HIV-uninfected by negative 4th generation HIV test during screening (prescribed group) * Documentation of negative HIV test within the last 3 months by outside laboratory OR evidence of PrEP prescription within the last 6 months based on medical records or pharmacy/provider communication * Owns an iOS or Android mobile phone with a camera and has private access to the internet * Able to understand, read, and speak English * Able to attend study visits at a local research site in San Francisco (Bridge HIV) (prescribed and non-prescribed groups) or virtual visits via a HIPAA-compliant teleconferencing platform (non-prescribed group) * Interested in starting or currently taking on-demand PrEP with TDF/FTC * Report having anal sex at least once a month and expecting to maintain at least this frequency of anal sex during study participation by self-report * Creatinine clearance ≥60 mL/min based on testing done during screening (prescribed group) * Have PrEP clinical and laboratory monitoring by another provider or clinic by self-report (non-prescribed group) * No contraindications to TDF/FTC use * No evidence of chronic HBV infection based on testing done during screening (prescribed group) * Willing to self-collect urine samples weekly Exclusion Criteria: * Repeatedly reactive HIV test at screening or enrollment or self-reported reactive HIV test (prescribed group) * Signs or symptoms of acute HIV infection at screening or enrollment * Currently enrolled in another PrEP intervention study. * Unable to commit to study participation for the duration of the study * Any medical, psychiatric, or social condition or other responsibilities that, in the judgment of the investigator, would make participation in the study unsafe, complicate interpretation of study outcome data, or otherwise interfere with achieving the study objectives.