Study Suggests Vaginal Gel Could Prevent HIV Infection in Women

Newly released clinical animal testing sheds some light on a potential future method of prevention for the HIV infection in women, an antimicrobial vaginal gel. This study, which focused on the effect of using the gel after sexual intercourse, resulted in positive findings in a sample of tested monkeys and suggested to researchers that the gel, which contains a one percent solution of the anti-HIV drug raltegravir, could be used to prevent HIV in human women. CDC statistical data indicates that sexual contact is the number one way HIV transmission occurs among females, yet, the gel is not expected to be ready to undergo the FDA approval process for at least several years.

Study

The study, which was released in the March 12, 2014, issue of Science Translational Medicine Magazine, found that the gel protected five out of six monkeys that were exposed to a hybrid simian/human AIDS virus when it was applied within three hours after the exposure. Additionally, the gel was found to be effective in two out of three monkeys when applied 30 minutes before the exposure. At the outset of the testing, the gel was first applied to the animals, which were then exposed to the virus twice a week for seven weeks. At the end of that phase, two of the three monkeys were virus-free, while in another control group of monkeys using a placebo and exposed in the same intervals, nine out of ten monkeys contracted the virus and only one was not infected. Subsequently, the researchers applied the gel three hours after exposure that occurred twice a week for two and a half months. Four out of the five animals in that sample that received the active gel did not contract the virus, while all four in the placebo-controlled group were infected.

A CBSNews article reported comments of Rowena Johnston, the vice president of amfAR, the Foundation for AIDS Research, who emphasized the importance of this potential method of prevention insofar as it can be used after sexual contact. Specifically, Johnston stated, “If you are having sex that’s in any way unanticipated, you might not have the opportunity to apply the microbicide before the sex happens.”

How it Works

 The vaginal gel contains the drug raltegravir, otherwise known under its brand name distinction Isentress®, which is classified as a HIV integrase inhibitor and has been effective in treating the HIV virus in those already infected. The gel, which contains the raltegravir, at the center of the study works to block the virus’ DNA from integrating into the animal’s DNA. According to the CBSNews report, since DNA integration has been highlighted by researchers as a “crucial step” in HIV infection, a product that functions to block that process may be a viable preventative tool.

Implications

According to CDC data, “among females, the largest percentage of new HIV infections was attributed to heterosexual contact,” that is, 84 percent of females in the U.S. were estimated to have contracted HIV through sex rather than through another means of transmission. Although Johnston, in the CBSNews piece, predicted that the vaginal gel could become as popular as birth control devices, the production of the gel for distribution on the market may not come for many years. The article’s authors noted that the effectiveness of the product on animals required more work and, only after researchers reached higher levels of effectiveness, would human testing occur. Confirmation that the gel would have the same effect on humans as it did on the monkeys in this experiment is necessary before introduction into the market can be considered.