Validation of a Urine Assay to Measure Tenofovir Levels in Patients Taking Tenofovir Alafenamide

Participants in cohorts 1a\&b will be administered FTC/TAF for 1 to 7 consecutive days and then be followed clinically for 6 to 14 days. Cohort 2 will participate in a 1 time blood and urine collection.