Vaginal Gel Might Prevent HIV Hours After Exposure
Lab tests with monkeys look promising, study says
Once the gel is applied, the HIV cannot transmit its DNA into cells, the researchers say.
"The DNA degrades and the cell does not become affected," Heneine said. Raltegravir has "been very effective in HIV treatment, and now we're looking at it in prevention," he added.
In the United States, the AIDS virus is mainly spread by having unprotected sex (sex without a condom) with someone infected with HIV, according to the U.S. Centers for Disease Control and Prevention.
Researchers first tested the gel's effectiveness pre-contact, by applying it to three monkeys who were exposed to HIV twice a week for seven weeks. By the end, two of the three remained HIV-free, compared with just one out of 10 monkeys in a group that received an inactive placebo gel.
The team then tested whether the gel could protect against HIV infection after exposure, using six monkeys exposed to HIV twice a week for two and a half months. By applying the gel three hours after exposure, researchers were able to protect five of the six monkeys from HIV infection. All four monkeys in the placebo group contracted HIV.
Such a gel, once through its clinical trials and approved, could become as widely used as birth control devices such as condoms and spermicidal gels, Johnston said.
"You can imagine this to be a useful product to have, if it were something you could buy over the counter and have at home just in case," she said.