If larger tests show the drugs work, they could be given to people at highest risk of HIV - from gay men in American cities to women in Africa who catch the virus from their partners.
The drugs are tenofovir (Viread) and emtricitabine, or FTC (Emtriva), sold in combination as Truvada by Gilead Sciences Inc., a California company best known for inventing Tamiflu, a drug showing promise against bird flu.
Unlike vaccines, which work through the immune system, AIDS drugs simply keep the virus from reproducing. The drugs already are approved for sale to help people infected with HIV from getting sicker. Officials at the U.S. Centers for Disease Control and Prevention hope to determine if Truvada can help prevent human HIV transmission by testing it in people in Botswana, according to the Associated Press.
Thomas Folks, a federal scientist since the earliest days of AIDS, told the AP, "This is the first thing I've seen at this point that I think really could have a prevention impact."
HIV spreads to 10 people every minute, 5 million every year.
