Use of Antiretrovirals for HIV Prevention: What Do We Know and What Don’t We Know?
Pre-exposure prophylaxis (PrEP), in which HIV uninfected persons with ongoing HIV risk use antiretroviral medications as chemoprophylaxis against sexual HIV acquisition, is a promising new HIV prevention strategy. Proof-of-concept that PrEP, as oral or vaginal topical tenofovir-based products, protects against sexual HIV acquisition has been demonstrated in clinical trials conducted among men who have sex with men and heterosexual men and women. The degree of HIV protection in these trials was strongly related to the level of adherence to PrEP. Many questions are yet unanswered – including how to motivate uptake of and sustain adherence to PrEP for HIV prevention, how much PrEP use is enough to achieve HIV protection, and the potential of “next-generation” PrEP agents to improve on this effective technology.
KeywordsAntiretroviral medications Chemoprophylaxis Global epidemic HIV/AIDS HIV prevention Pre-exposure prophylaxis (PrEP) Sexual HIV transmission
The authors acknowledge the funding support of US National Institutes of Health (R01 MH095507, R01 AI064002, R01 AI062333), the Bill & Melinda Gates Foundation (grants 47674 and 48162) and Gladstone Institutes.
The authors have conducted research studies related to pre-exposure prophylaxis for HIV prevention supported with grant funding from the US National Institutes of Health, the US Agency for International Development, the Bill & Melinda Gates Foundation, and the US Centers for Disease Control and Prevention. Gilead Sciences provided study medication for these studies but did not provide funding to the authors or their institutions.
Conflict of Interest
Jared Baeten declares that he has no conflict of interest.
Robert Grant declares that he has no conflict of interest.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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