Two studies find that oral antiretrovirals can reduce the risk of HIV
July 13, 2011 -- Results announced today from two studies show that a daily antiretroviral (ARV) pill taken by people who do not have HIV can reduce their risk of transmission by up to 73 percent. Both daily tenofovir and daily tenofovir/emtricitabine taken as preventive medicine through a method known as PrEP—or pre-exposure prophylaxis—can prevent heterosexual transmission of HIV from men to women and from women to men.
The Partners PrEP trial, conducted by the University of Washington’s International Clinical Research Center, followed almost 5,000 couples in Kenya and Uganda. The couples—in which one partner was HIV-positive and the other was HIV-negative—received counseling and free male and female condoms. The HIV-negative partner took a once-daily tenofovir tablet or a tenofovir/emtricitabine tablet or a placebo pill. There were 62 percent fewer HIV infections in the group receiving tenofovir and 73 percent fewer HIV infections in the group that took tenofovir /emtricitabine than in the group receiving the placebo.
The TDF2 trial, conducted by the Centers for Disease Control and Prevention (CDC), followed 1,200 men and women in Botswana who received either a once-daily tenofovir/emtricitabine tablet or a placebo pill. The antiretroviral tablet reduced the risk of acquiring HIV infection by roughly 63 percent overall in the study population of uninfected heterosexual men and women.
“These results are tremendously exciting and confirm that we are at pivotal period in the AIDS epidemic,” said Mitchell Warren, executive director of the AIDS Vaccine Advocacy Coalition (AVAC). “Antiretroviral drugs for HIV treatment began to turn the tide of the epidemic 15 years ago, and it is clear that also using ARVs for HIV prevention will strengthen our response to AIDS.”
“These are exciting results for global HIV prevention. We now have findings from two studies showing that PrEP can work for heterosexuals, the population hardest hit by HIV worldwide,” said Kevin Fenton, director of CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and Tuberculosis Prevention. “Taken together, these studies provide strong evidence of the power of this prevention strategy.” See the links below for more information.
- AVAC press release
- AVAC PrEP information
- CDC press release
- International AIDS Vaccine Initiative press release
- International Partnership for Microbicides press release
- Los Angeles Times