HIV Prevention: Opportunities and Challenges

Abstract

Preexposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF)-based regimens has been shown to be effective in preventing acquisition of HIV infection, with protective efficacy being dependent on adherence to treatment. Data from the PROUD (Preexposure Option for Reducing HIV in the UK) and IPERGAY (Action to Prevent Risk Exposure By and For Gay Men) studies, the later of which employed event-driven PrEP, showed a high rate of protective efficacy of PrEP with TDF and emtricitabine among men who have sex with men. Data from the ASPIRE (A Study to Prevent Infection With a Ring for Extended Use) study of a dapivirine vaginal ring showed a moderate rate of protective efficacy among women older than 21 years. Ongoing investigations are examining long-acting PrEP modalities and combination PrEP and contraception products. This article summarizes a presentation by Jeanne M. Marrazzo, MD, MPH, at the IAS-USA continuing education program, Improving the Management of HIV Disease, held in Washington, DC, in April 2016.

Figure.

Protective efficacy of the dapivirine vaginal ring in the ASPIRE (A Study to Prevent Infection With a Ring for Extended Use) trial, by age group: (top) among participants aged 18 to 21 years efficacy of HIV protection was −27% (95% CI, −133 to 31); (middle) among participants aged 22 to 26 years efficacy of HIV protection was 56% (95% CI, 19 to 76); (bottom) among participants aged 27 to 45 years efficacy of HIV protection was 51% (95% CI, 8 to 74). Adapted from Baeten et al.