A gel that uses a popular HIV drug to protect women from the AIDS virus is safe and acceptable to women, although it is too early to know if it actually prevents infection, researchers reported on Monday.
The gel uses the drug tenofovir, sold under the name Viread by Gilead Sciences Inc..
The study, released at a meeting of AIDS researchers in India, is a welcome piece of good news for the struggling field of microbicides. It involved 200 sexually active HIV-negative women in the United States and India.
“The gel is safe to use, and well tolerated by HIV-negative women. That’s a key message in our findings,” said Dr. Craig Hoesley of the University of Alabama at Birmingham. “This sets the stage for larger studies to see if tenofovir can prevent HIV infection.”
Microbicides are products, such as gels or creams, that can be applied vaginally or anally to prevent transmission of the human immunodeficiency virus that causes AIDS.
Just last week a study showed one candidate, called Carraguard, did not protect women from infection.
'Turning a corner'
Two other potential microbicides have made women more likely to become infected — a spermicide called nonoxynol-9 and a product called Ushercell, made by Toronto, Canada-based Polydex Pharmaceuticals.
The tenofovir product appears to be safe, said the research team, funded by the National Institutes of Health, found. It is the first potential microbicide to use a licensed AIDS drug.
It was a phase II clinical trial designed to show safety, not that it was effective.
“It is a critical time for all of us engaged in HIV prevention, and I truly believe we are turning a corner,” said Sharon Hillier of the University of Pittsburgh School of Medicine, who led the study.
Women make up 46 percent of the 33.2 million people infected with the AIDS virus, according to the United Nations Agency UNAIDS.
Hillier said it is not clear how long tenofovir stays in a woman’s vagina.
“Currently, there are very encouraging studies suggesting that even when tenofovir is gone from the vagina the drug itself is there in the vaginal tissue,” Hillier said in an e-mail.
“The important thing we learned is that covert use, or secret use, is not an important parameter for women, and that in fact we found that 12 percent of the women who used to the gel said it made sex more pleasurable and none of the women said that the gel made sex less pleasurable.”
Eighty percent of the women told to use gel within two hours of having sex said they had done so.
“We asked women ’How acceptable is this as a prevention option, is it too messy, is it a nuisance, and will you use it?’ Our study showed they will use it and they’re not bothered by the gel,” Hoesley said.