Clinical Research Directory

Inclusion Criteria Young men who meet all of the following criteria are eligible for inclusion: * PrEP-eligible YMSM * Ages 18-24 * Biologically born male * Report interest in PrEP * Intend to use PrEP for a full 6 month period * Eligible to be a PrEP patient at the CORE Center PrEP Clinic * Meet one the following sexual risk criteria: * Have an HIV-positive sexual partner * Had recent bacterial STI * Report high numbers of sexual partners * Report history of inconsistent or no condom use * Report exchange/transactional sex. Exclusion Criteria Young men who meet any of the following criteria will be excluded: * HIV+ * Creatinine clearance \<60 cc/min) * Allergy to topical adhesive * Acute gastrointestinal symptoms * History of major GI surgery * Presence of an implanted electronic medical device. * Subjects who are receiving any of the following medications:Nephrotoxic drugs (e.g., cidofovir, amphotericin, aminoglycosides, dapsone, tacrolimus, foscarnet, ACE inhibitors), all diuretics, drugs that may interfere with TFV excretion (e.g., (Val)ganciclovir, Cyclosporin A, Sirolimus, Antineoplastics), drugs (not including mineral and vitamin supplements) used for treatment of osteoporosis (e.g., alendronate and other bisphosphonates, teriparatide, denosumab, and calcitonin), chronic use of oral or systemic steroids (i.e., daily use for two weeks or more is not allowed), experimental medications that are not Food and Drug Administration (FDA)-approved, and FTC/TDF (Truvada®) received outside of the study