Maximizing the Benefits of HIV Preexposure Prophylaxis

Preexposure prophylaxis (PrEP) with tenofovir/emtricitabine (slash indicates coformulation) is highly effective in preventing new HIV infections. PrEP efficacy is strongly associated with adherence. In clinical trials, PrEP has been more effective in men who have sex with men and HIV-serodiscordant heterosexual couples than in women, likely reflecting pharmacokinetic differences between levels of tenofovir disoproxil fumarate in vaginal and rectal tissues, and poorer adherence in studies in women. Current guidelines recommend daily PrEP for men and women; however, PrEP taken at least 4 days per week for men may be as effective as daily PrEP, and women must take PrEP 6 to 7 days per week to maximize efficacy. Data are accumulating on the effectiveness of pericoital PrEP for men who have sex with men, but it is not yet recommended in the United States. PrEP is underprescribed for younger individuals, black individuals, and Hispanic and Latino individuals. This article summarizes a presentation by Susan P. Buchbinder, MD, at the IAS–USA continuing education program, Improving the Management of HIV Disease, held in Chicago, Illinois, in May 2017