New Study Results Hold Promise for HIV Prevention

Evidence supports pre-exposure prophylaxis (PrEP) as effective HIV prevention strategy

Foundation urges development of demonstration projects to assess PrEP’s feasibility in the U.S.


San Francisco, July 13, 2011 – San Francisco AIDS Foundation is encouraged by reports from two new studies conducted in African countries confirming data from earlier trials that show antiretroviral drugs (ARVs) currently used to treat HIV can also be used to prevent new HIV infections, when offered as part of a comprehensive prevention package including condoms and counseling, among diverse populations.
One study, called “Partners PrEP,” was conducted in Kenya and Uganda and involved 4,758 heterosexual couples in which one partner was HIV positive and the other was HIV negative. This trial showed daily oral tenofovir (Viread, also called TDF) and tenofovir combined with emtricitabine (Emtriva) in the Truvada pill reduced the risk of HIV infection in both men and women. In this study, tenofovir reduced risk of HIV infection by 63 percent and Truvada reduced infection risk by 73 percent compared with a placebo pill. Both drugs were effective in men and women, and there appeared to be no significant safety issues in the trial.

The other study, called “CDC TDF2,” conducted in Botswana among 1,219 heterosexual men and women, showed that a daily dose of Truvada reduced risk of HIV infection overall by approximately 63 percent. In a sub-analysis among participants who were considered to be taking the study drug most consistently, Truvada reduced HIV infection risk by 78 percent. Participants in this trial also did not experience any significant safety concerns.

These findings, in combination with those from the iPrEx trial among gay and other men who have sex with men reported late last year, demonstrate that PrEP can be an effective HIV prevention strategy among a range of population groups. They also underscore the importance of drug adherence—that is, taking ARVs consistently, as prescribed—in significantly reducing HIV infection risk.

It is now imperative to consider how these findings from highly controlled research studies translate into “real world” public health practice, and the potential of PrEP to reduce HIV incidence at the population level. San Francisco AIDS Foundation, in partnership with other organizations and public health officials, is participating in advocacy for and development of demonstration projects to evaluate the feasibility of PrEP in our city and elsewhere in the United States.

The foundation recognizes that, as encouraging as the new PrEP findings are, no single prevention approach meets the needs of all people vulnerable to HIV. PrEP may be best targeted to those for whom it is most desirable, feasible, and effective, while other prevention methods already known to be effective can be advocated for others. The demonstration projects will help us answer these questions and ensure our limited resources are spent in the most responsible way with the greatest impact on eliminating HIV/AIDS.


About San Francisco AIDS Foundation
No city experienced epidemic levels of HIV faster than San Francisco.  At San Francisco AIDS Foundation, we work to end the epidemic where it first took hold, and eventually everywhere. Established in 1982, our mission is the radical reduction of new infections in San Francisco.  Through education, advocacy and direct services for prevention and care, we are confronting HIV in communities most vulnerable to the disease. We refuse to accept that HIV transmission is inevitable.

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