THURSDAY, Dec. 23, 2004 (HealthDayNews) -- Over the next few months, officials in two U.S. cities and several other countries will begin testing whether a popular AIDS drug can protect healthy people against HIV infection.
If the tests are successful, they could lead to the first AIDS prevention pill, potentially giving millions of people a way to have sex and avoid infection.
The researchers have to resolve many issues first, from questions of cost to concerns about encouraging unsafe sex. But for now, officials are crossing their fingers as the drug studies get under way.
"The hope is that uninfected individuals will find it [the drug] to be safe, effective and easy to take on a regular basis when they're in situations of high exposure," said Dr. Willard Cates Jr., president of Family Health International, a nonprofit public health organization that will run several studies based in Africa.
The research will begin in earnest in January and February, when thousands of healthy people will begin taking daily doses of either the AIDS drug tenofovir, known as Viread, or a placebo.
Some of the research has already begun. The subjects will include 400 sexually active gay men in San Francisco and Atlanta; 1,700 heterosexuals in West Africa; and 1,600 heterosexuals in Thailand. The National Institutes of Health was going to launch another study involving 1,000 Cambodian prostitutes, but officials in that country had qualms about the research and squashed the project.
Tenofovir, which goes to work during the early-to-middle stages of HIV infection, prevents the hijacking of a cell's DNA by the AIDS virus. There's speculation in the medical community that Tenofovir, one in a "cocktail" of drugs taken by many AIDS patients, is strong enough to stop HIV from infecting a person in the first place.
The studies, which may take two years to complete, are designed to test the safety of tenofovir treatment. Although some AIDS drugs cause a variety of unpleasant side effects, medical officials say tenofovir produces relatively few problems.
While the initial testing is designed to gauge the drug's safety, Dr. Susan Buchbinder, director of HIV research for the San Francisco Department of Public Health, said, "We have no idea whether tenofovir will reduce the number of HIV infections. We want to start with this safety question [and investigate] whether taking a pill alters risk behavior."
The researchers say they don't want any trial participants to become infected with HIV. Everyone will undergo regular counseling and receive condoms and treatment for sexually transmitted diseases, Cates said: "We'll try our best to have nobody get infected."
While tenofovir treatment costs $450 a month in the United States, its manufacturer -- Gilead Sciences of Foster City, Calif. -- plans to offer it for 70 cents a pill in the study, according to Cates, and the price may even go down to 50 cents.
The studies are sure to be controversial. Critics have balked at the idea of using an AIDS drug to treat people who aren't sick when there are millions of infected people -- especially in Africa -- who have little or no access to medicines.
Cates views the research in a different light. "It's really not an either-or," he said. "We obviously need to provide drugs and treatment for those who are sick, but at the same time, we need to learn more about new ways to prevent those who are not infected from getting infected."
To learn more about tenofovir, visit the U.S. National Institutes of Health.