For the first time, AIDS researchers report success with an HIV-prevention tool that can be controlled by women: a vaginal gel containing the antiretroviral drug tenofovir. Although women account for nearly half of all new HIV infections each year, they have few options for protection. The best strategies — using condoms or practicing abstinence — require cooperation from often unwilling partners.
In a preliminary study of 889 women in South Africa, those who used the antimicrobial gel, which contains 1% tenofovir, before and after sex for 2½ years reduced HIV infection by 39%, compared with women who used placebo. Among women who used the gel most faithfully as directed, infections were cut by 54%. What's more, the gel halved the chances of contracting the genital-herpes virus, another risk factor for HIV.
The gel isn't the first of its kind. But unlike previous, failed versions of vaginal microbicides, which attempted to either neutralize HIV on contact or create a physical barrier between the virus and healthy cells, the new formulation incorporates a potent anti-HIV drug that appears to block infection more effectively.
In 2011, scientists hoping to expand on these promising results, tested the gel against rectal transmission of HIV as well. In a small study in which volunteers provided biopsied tissue cultures after regularly applying the gel or a placebo to the rectum for a week, researchers found that cells from people who used the gel were better able to withstand HIV infection in a lab dish than those from people who used placebo.
Source: healthland.time.com
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