Anti-HIV vaginal gel could also reduce genital herpes by half: Study

By Dr. Ananya Mandal, MDOct 24 2011

New research has shown that a drug used as gel in prevention of HIV transmission could be useful against genital herpes.

The study appears this week in the journal Cell Host & Microbe that tested the gel on women in South Africa (where the risk of HIV and herpes is great) found that the anti-HIV/AIDS drug tenofovir reduced herpes infections by 51% and HIV infections by 39%.

Researchers at National Institutes of Health, Gilead Sciences Inc. and universities in Belgium and Italy further note, that in human tissue, the drug inhibits enzymes that the virus needs in order to replicate. But to protect against herpes, tenofovir needs to be topically applied to the vaginal canal. 450 women who participated in the study were asked to apply the gel topically before and after sexual intercourse.

“This could be incredibly helpful,” Dr. Jeanne Marrazzo, a  herpes expert at the University of Washington’s medical school said.   ”Protection that a woman can control is the holy grail in this field. It’s hard for me to believe that something that protects against both HIV and herpes wouldn’t be appealing to a lot of young American women.”

This would be the first time that an HIV-prevention method controlled by women has been shown to work. Tenofovir-maker Gilead Sciences Inc., which was involved in the study, has not made a statement on its further development for the US market. The gel could take years to get to the consumer market, researchers say.

Genital herpes is not fatal, but it is painful and wrought with a heavy social stigma. About 20 percent of sexually active adults worldwide have genital herpes, according to the World Health Organization. It can be spread through skin-to-skin contact during sex, along with vaginal fluids and semen, even if neither partner shows the sores.

The unexpected reduced risk of the herpes infection came from a 2010 trial conducted in South Africa, which found that the gel reduced the risk of AIDS infection by 39 percent. “The tenofovir trial is being repeated to ensure that the results regarding HIV protection are real and are generalizable,” Justin O’Hagen, an infectious disease epidemiology doctoral student at Harvard School of Public Health said.  ”Undoubtedly they will also collect further data on tenofovir’s effect on herpes so there will be even more publications on this, roughly in early 2013,” he added.