Why was tenofovir/emtricitabine selected for this study?
FTC/TDF was selected because it has been shown to be safe and effective with few side effects. In studies in macaques, the drug was shown to prevent the transmission of the monkey version of HIV (simian human immunodeficiency virus, or SHIV) without serious side effects. FTC/TDF is taken orally once daily, remains in the bloodstream for many hours, and was well tolerated in safety trials involving people not infected with HIV.