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Pre-Exposure Prophylaxis News 

PrEP, short for PreExposure Prophylaxis, may be part of comprehensive HIV prevention services in which HIV negative people who are at high risk take antiretroviral medication daily to try to lower their chances of becoming infected with HIV if they are exposed to it. To date, PrEP has been shown to be effective in men who have men who have sex with men (MSM), transgendered women who have sex with men, as well as sero-discordant heterosexual couples. Studies are underway to evaluate whether it is safe and effective in reducing HIV infection among injection drug users, however those results are not yet available.

PrEP programs in California are currently in the planning and development stages.

Study Summaries

This study evaluated the use of tenofovir/emtricitabine (Truvada), a medication used to treat HIV infection, in the prevention of HIV infection among men who have sex with men, and showed some efficacy. This iPrEX study supplies the first evidence that taking a daily oral antiretroviral drug can help prevent sexually acquired HIV infection when delivered as part of a comprehensive package of prevention services that included condoms, intensive behavioral counseling and sexually transmitted infection diagnosis and treatment.  Even though other studies will have to be completed to determine if PrEP will prove effective in real world settings and for additional populations, the results from this trial are an advance in addressing the HIV epidemic among MSM in the United States –that could potentially provide an additive effect to current proven HIV prevention measures.

The Partners PrEP study, led by the University of Washington’s International Clinical Research Center, was the first to show that PrEP reduces HIV risk in heterosexual serodiscordant couples (where one partner is HIV positive and the other is not).  The study involved 4,758 participants from nine test sites in Kenya and Uganda.  These results were of major significance for Sub-Saharan Africa, since a substantial number of new HIV infections occur among heterosexual men and women in that region.  Results of this study were announced in a press release dated July 13, 2011

The CDC TDF2 study, conducted in partnership with the Botswana Ministry of Health, found that a once-daily tablet of Truvada reduced the risk of acquiring HIV infection by 63 percent overall in HIV uninfected heterosexual men and women.

CDC Interim Guidance and Information

The Centers for Disease Control and Prevention (CDC) has developed initial media statements and informational documents:

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Last modified on: 1/22/2015 11:05 AM