Tenofovir as HIV prevention: study to reduce HIV transmission in sexually active adults

The Bill and Melinda Gates Foundation has announced that it has awarded Family Health International (FHI) a $6.5 million, three-year grant for a multinational clinical trial to evaluate an antiretroviral treatment as a novel approach to HIV prevention. The trial will focus on sexually active adults in resource-poor countries with high HIV incidence.

The FHI study is designed to evaluate the safety and efficacy of the antiretroviral tenofovir disoproxil fumarate (tenofovir DF) as a method of reducing the risk of HIV infection in sexually active adults who are regularly exposed to the virus. The study will also assess the acceptability of, and adherence to, a regimen of one tenofovir DF tablet taken once daily. Gilead Sciences developed tenofovir DF and is supplying the drug for this study. As an antiviral treatment, tenofovir DF has several characteristics that make it a promising candidate as a method of HIV prevention, including its safety, efficacy, pharmacokinetic and resistance profiles.

Although condoms are a proven method for preventing the spread of sexually transmitted diseases, including HIV, women often are unable to successfully negotiate the use of this method by their partners. Thus, the urgency for expanded prevention options is greatest for women. If shown to be safe and effective in this setting, tenofovir DF could be an HIV prevention method used by men or women.

“It is imperative that we not only strive to develop new drugs, but that we also consider new uses for existing ones, such as tenofovir DF, which has tremendous potential as a dual HIV treatment and prevention technology,” said Ward Cates, president of FHI’s Institute for Family Health. “Our goal with this unique study is to help guide public health decision-making that spurs the delivery of HIV prevention tools to men and women around the world.”

“Convenient, reliable and effective methods of HIV prevention are urgently needed,” said Helene Gayle, director HIV/AIDS and TB at the Bill and Melinda Gates Foundation. “Previous experience with antiretroviral therapy in reducing the acquisition risks in healthcare workers and newborns exposed to HIV gives us hope that they may be an effective method of preventing sexual transmission of HIV.”

Dr Gayle serves as co-chair of the Global HIV Prevention Working Group, which this summer issued its blueprint for action. In its report, the working group highlighted the need for new, novel technologies to reduce transmission of HIV. The working group also underscored the importance of efforts that will empower women to decrease their vulnerability to HIV.