Truvada (Gilead), an oral fixed-dose combination of the antiretrovirals emtricitabine and tenofovir disoproxil fumarate frequently used for treatment of HIV infection,1 has now also been approved by the FDA for pre-exposure prophylaxis to reduce the risk of sexually acquired HIV-1 in adults at high risk. It is the first drug to be approved for this indication. The CDC has been recommending Truvada off-label for pre-exposure prophylaxis in men who have sex with men since 2011.2 A 30-day supply of Truvada costs about $1160.3

CLINICAL STUDIES — Approval for the new indication was based on 2 randomized, placebo-controlled trials in high-risk patients. One trial in 2,499 HIV-negative men (or transgender women) who have sex with men found that daily use of the combination reduced the risk of HIV seroconversion by 44% (36 seroconversions vs. 64 with placebo).4 A post-hoc analysis found that the rate of infection was reduced by 87.5% compared to placebo among men found to be adherent to the drug regimen (i.e., had detectable intracellular tenofovir levels).5 The second trial included 4,747 heterosexual couples among whom one partner was HIV-infected and the other was not. Truvada reduced the risk of becoming infected by 75% (13 seroconversions vs. 52 with placebo).6

RECOMMENDATIONS — Pre-exposure prophylaxis with Truvada should be considered only for persons who are at high risk for HIV-1 acquisition, are confirmed to be HIV-negative and are willing to take the drug once daily and practice safer sex. Frequent follow-up HIV antibody testing is recommended while taking the drug to ensure early diagnosis of newly-acquired HIV infection; resistance to tenofovir/emtricitabine can develop if it is taken prophylactically by patients with HIV infection.