Pre-Exposure Prophylaxis (PrEP)


Parallel Comparison of Tenofovir and Emtricitabine/tenofovir Pre-Exposure Prophylaxis to Prevent HIV-1 Acquisition within HIV-1 Discordant Couples.

Primary Objectives:

  • To determine if once-daily, oral PrEP with TDF or FTC/TDF provides additional protective benefit in preventing HIV-1 acquisition among HIV-1 uninfected persons within heterosexual HIV-1 discordant couples who are also receiving standard prevention interventions.
  • To assess the safety of daily PrEP using TDF or FTC/TDF by comparing rates of adverse events (AEs) among HIV-1 uninfected individuals randomized to TDF or FTC/TDF PrEP to those randomized to placebo.


Phase III, multi-site, randomized, double-blind, placebo-controlled trial.


Heterosexual HIV-1 discordant couples. The HIV-1 uninfected partners may be either male or female, and must not be chronically infected with hepatitis B. At the time of study screening, the HIV-1 infected partner must have a CD4 count less than or equal to 250 and must not otherwise meet national guidelines for initiation of antiretroviral therapy.

Study Size:

3900 HIV-1 seronegative partners within HIV-1 discordant couples (1300 in each treatment arm) are estimated to be needed for this endpoint-driven trial.