METHODS
We conducted a randomized, placebo-controlled trial to assess daily treatment with
oral tenofovir disoproxil fumarate (TDF), oral tenofovir–emtricitabine (TDF-FTC), or
1% tenofovir (TFV) vaginal gel as preexposure prophylaxis against HIV-1 infection in
women in South Africa, Uganda, and Zimbabwe. HIV-1 testing was performed monthly,
and plasma TFV levels were assessed quarterly.