Contingency Management for Methamphetamine Abstinence and HIV Post-Exposure Prophylaxis in Men Who Have Sex With Men

Inclusion Criteria: * Individual must identify as a male who has sex with other men (MSM); * At least 18 years of age; * HIV negative serostatus on baseline rapid oral HIV antibody test; * Self-reported methamphetamine use within the previous 72 hours and test positive for methamphetamine metabolites at baseline; * Self-reported unprotected anal intercourse (either receptive or insertive) with an HIV-positive or status unknown partner within the previous 3 months; * Self-reports no previous hypersensitivity to any of the components of Truvada (tenofovir disoproxil fumarate or emtricitabine); * Willing to comply with study requirements (i.e., monitored urine testing three times per week, meet with physician within first week of enrollment, begin medication immediately following an unexpected high-risk sexual exposure, and contact the clinic and meet with physician within 92 hours of unexpected high-risk sexual exposure). Exclusion Criteria: * Does not identify as a male who has sex with other men; * Under 18 years of age; * HIV positive, by self-report or as indicated by the results on the baseline rapid oral HIV antibody test; * Self-reports any previous hypersensitivity to any of the components of Truvada; * Has not used methamphetamine in the previous 72 hours and does not test positive for methamphetamine metabolites; * Has not had unprotected anal intercourse with an HIV-positive or status unknown partner within the previous 3 months; * Unwilling to comply with study r…