The State of the Science on PrEP and Treatment as Prevention
The latest on two HIV prevention strategies is just a click or a tap away, thanks to a free, full-text article available online from the November issue of Current Opinion in HIV and AIDS.
In their comprehensive review piece, researchers Jared Baeten, MD, PhD, and Connie Celum, MD, MPH, detail the current state of the science on oral antiretroviral-based HIV prevention. The article covers both pre-exposure prophylaxis (PrEP), in which HIV-negative individuals take antiretroviral drugs to avoid HIV infection, and treatment as prevention, whereby the risk of HIV transmission to sex partners is reduced when HIV-positive people are on successful antiretroviral therapy.
Baeten and Celum present the rationale behind each approach, discuss the clinical trial results—including possible reasons why trials found PrEP worked better in men than in women—and look ahead to next steps for these HIV prevention tools. “Successful HIV prevention on a population scale will need to incorporate multiple, evidence-based biologic and behavioral strategies to achieve maximal benefits, including behavior change, HIV testing, male circumcision, antiretroviral treatment for HIV-infected persons and PrEP,” the authors conclude.
Looking for an in-depth discussion of these new prevention approaches and the science behind them? Check out the abstract below, and view or download the full article here.
By Jared Baeten and Connie Celum
Current Opinion in HIV and AIDS 7(6): 514–519. November 2012.
Purpose of review: Preexposure prophylaxis (PrEP), in which HIV uninfected persons with ongoing HIV risk use oral antiretroviral medications as chemoprophylaxis against sexual HIV acquisition, is a promising new HIV prevention strategy.
Recent findings: During the past 2 years, proof-of-concept that PrEP protects against sexual HIV acquisition has been demonstrated in three clinical trials, conducted among MSM and heterosexual men and women. These trials used daily oral tenofovir disoproxil fumarate, alone or coformulated with emtricitabine. The degree of HIV protection in these trials was strongly related to the level of adherence to PrEP. Two additional clinical trials, both among heterosexual women, did not demonstrate HIV protection with PrEP, with low adherence to daily use of PrEP the leading hypothesis for lack of efficacy; adherence and biologic mechanisms for lack of efficacy in these trial populations are being evaluated.
Summary: Oral chemoprophylaxis, using tenofovir and combination emtricitabine–tenofovir, is effective for prevention of sexual HIV transmission. Next steps in the field include rigorous evaluation of uptake and adherence to PrEP in implementation settings.