July 29, 2010
Gel found to reduce AIDS risk in women
Kevin Mark Kline READ TIME: 4 MIN.
A study reports that tenofovir, a common HIV drug, if used topically by women in gel form 12 hours before or after sex can significantly reduce the risk of HIV infection.
The research marks a gusher of success after a 15-year drought in the search for a women's HIV prevention modality providing them independence.
"This is a very exciting development with potentially huge impacts on all communities of women," said Michelle Simek, a women's AIDS prevention specialist working for AIDS Project Los Angeles (APLA).
She listed several non-English speaking minorities in and around LA County including African-American, Korean-American and Armenian-American that "have less control over their safe-sex practices."
According to reports, two scientists with the Center for the AIDS Program of Research in South Africa (CAPRISA) conducted the study in and presented their work Tuesday at the 18th International AIDS Conference in Vienna.
The microbicide, cited as a breakthrough, reduced the risk of HIV infection by 39 percent in a group of women who used it for 75 percent of their sexual encounters.
Those who used it more consistently than three out four times experienced 54 percent fewer infections.
Scientists lauded the announcement as a major step, saying that pharmaceutical firms will develop more-potent formulations, combining that with social marketing campaigns to make the product appealing (or even sexy), promoting adherence and increased effectiveness.
Women represent nearly half of all current AIDS infections with 16 million women (of 33 million people) worldwide infected with HIV.
In Africa, 60 percent of people with HIV infection are women, nearly all of whom acquired the virus through sex.
Because jail officials refuse to provide meaningful prevention methods in jails and prisons, she said, "We have an HIV incubator for minority communities in the jails where men have sex while incarcerated without condoms [because they are banned]; they get infected with HIV and return home to their wife or girlfriend..." with whom they are likely not to allow the use of a condom.
Because of that and other social pressures (such as the African-American urban down-low phenomenon and the large Hispanic population that both stigmatizes and turns a blind eye to men who have sex with men, here in Los Angeles County, according to Ms. Simek, African American women account for 70 percent of infections among HIV+ women, compared to a national rate of 65 percent.
She said that for these women proven prevention methods such as abstinence, monogamy and condom-use stand outside their control.
Using a vaginal microbicide without their partners' knowledge stands as the only way for them to take control of their sexual health.
Ms. Simek said the prevention community in Los Angeles was abuzz with the news, although it should be some years before the FDA approves a gel for general use and it goes onto shelves.
First, according to the company, researchers must demonstrate the microbicide's effectiveness in another group of women.
While clearing scientific and approval hurdles now sits as priority one to the international HIV research community, it is unlikely a practical application can be ready before 2014-15, said Ms. Simek.
IN other prevention news, the Washington Post reports that "a larger study testing tenofovir gel and antiretroviral drugs in pill form as a way to protect women against sexual transmission of HIV is underway in four African countries but will not be finished until 2013.
"Several other experiments, including ones in which the drug is in a long-acting vaginal ring, are in earlier stages.
"A microbicide might also be useful in protecting men who acquire the virus through anal sex."
In the tenofovir gel study, scientists randomly assigned a group of HIV-negative urban- and rural-women use of a gel containing either 1 percent tenofovir or a placebo.
The material came packed in syringe-like applicators with instructions to inject the gel into the vagina no more than 12 hours before intercourse and again within 12 hours afterward.
Researchers collected both used and unused applicators to verify the women's reports on how many they used; each of the women received a monthly AIDS test.
At the end of 30 month, researchers found 98 infections in the 889 women they studied.
The HIV incidence, measured as the number of new infections for every 100 "women years" in the study, stood at 5.6 in the volunteers using the tenofovir gel and 9.1 in those with the placebo gel, showing a rate of effectiveness of 39 percent.
Among women who said they used the gel for at least 80 percent of episodes of intercourse, the effectiveness was 54 percent.
Another benefit accruing to the tenofovir gel user seemed to be herpes prevention, say researcher.
According to their work, tenofovir gel decreased a woman's risk of getting genital herpes, a virus that also increases her chance of acquiring HIV if she has intercourse with an HIV-infected man.
Tenofovir provided protection enough that half as many women using gel with the drug in it became infected as did those using the placebo gel.