SAN FRANCISCO (AP) — AIDS prevention advocates are hailing a pill newly shown to protect against HIV as a great tool for disease prevention.

But they caution that no drug alone can address social factors blamed for the persistence of the epidemic. And they say concerns remain about who will pay for the costly treatment.

A study released Tuesday showed that daily doses of a drug called Truvada, already used to treat HIV infection, cut the risk of new infections among healthy gay men.

Kyriell Noon of the San Francisco-based Stop AIDS Project said any addition to the HIV prevention safety net is good news. But he said factors, such as lack of access to education and health care that contribute to higher infection rates, do not evaporate when a promising drug comes along.

Truvada, which costs $5,000 to $14,000 a year in the United States, will do little to halt HIV’s spread if the only way to get it is to pay out of pocket, Noon said.

“The history of the HIV epidemic in this country has been a story of disparities,” he said. “I would hate to see this new exciting breakthrough enhance those disparities.”

Noon’s group was among those that helped recruit participants for the study in San Francisco, which has more than one new HIV infection every day, according to the city’s Department of Public Health.

The overall study involved about 2,500 men at high risk of HIV infection in Peru, Ecuador, Brazil, South Africa, Thailand and the United States (San Francisco and Boston).

Dr. Susan Buchbinder, director of the San Francisco health department’s HIV research section, called the findings on the drug a “tremendous step forward.” But she took pains to point out that among the several HIV prevention studies she has overseen, this latest had especially strict requirements for making sure participants stayed on track.

Men taking Truvada had to commit to monthly medical visits and received extensive counseling, including reminders about the importance of condoms. Such reminders seemed to have worked: During the study, risky sex among men taking Truvada declined.

But concern exists that in the real world, some men will see Truvada as a license to be promiscuous and shed precautions such as condoms. A follow-up study will track participants who remain on the drug to see if that happens.

Ronny Nolasco, 28, of San Francisco participated in the Truvada study and said he is looking forward to being part of the follow-up. While he was pleased to hear about the study’s findings about the drug, the counseling he received was at least as important, he said.

“It helped me out a lot,” Nolasco said. “It actually opened up my eyes to taking more care of myself.”

Advocates say experiences like Nolasco’s are why just handing out the drug will not be enough.

“Our goal is to try to combine prevention interventions,” Buchbinder said. “It’s not about just popping a pill every day.”

Yet for many healthy gay men, the question of whether to take a daily dose of Truvada will likely become an important issue.

Public health officials say they are working on defining who falls into the highest risk groups who would benefit most from the drug.

Jason Meier, 32, has already made up his mind. The self-described single, sexually active gay man from Birmingham, Ala., said he would ask his doctor for the drug.

Meier, a student affairs staffer at The University of Alabama at Birmingham, said taking one pill a day before contracting HIV is better than taking multiple pills after becoming infected.

“Condoms aren’t 100 percent safe,” Meier said. “In this day and age, you can’t trust a partner to be honest about their sexual activity or history. At some point, you have to take responsibility for safer sexual practices.”

Meier said paying for the drug now makes financial sense compared to the expense of post-infection treatment. But broad government or insurance company funding for the drug for prevention rather than treatment would not come before U.S. Food and Drug Administration approval.

Even then, funding for the drug as a prevention measure could be divisive in the U.S. if such use is seen as encouraging sexual activity.

For now, the drug’s maker, Gilead Sciences Inc., is still deciding whether to seek federal approval to market Truvada as a way to prevent HIV infection. In the meantime, doctors can prescribe the drug off-label for that use.

But advocates are holding off on recommending that gay men seek out their doctors for prescriptions.

“I think the bigger question will be, will the FDA decide that this study is enough?” said Judy Auerbach, vice president of research and evaluation for the San Francisco AIDS Foundation.

The foundation’s message to those who ask about the drug will be not to experiment with the drug on your own, Auerbach said. She called the drug promising but said all the traditional ways of preventing infection should still be emphasized.

“If you really want to pursue this go talk to your medical provider, and they’ll make an assessment. I think that’s all we can say at this point.”

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