FDA Approves First Drug for HIV Prevention July 16, 2012 -- The FDA has approved use of the HIV drug Truvada to help people at high risk avoid infection with the AIDS virus.

Truvada is already approved as part of treatment regimens for people with HIV infection. But this is the first time the FDA has approved any drug for "pre-exposure prophylaxis" or PrEP -- that is, for protecting uninfected people against HIV.

It is not a prescription to party, says Debra Birnkrant, MD, the FDA's director of antiviral products.

"We stress that PrEP with Truvada must include safer-sex practices, counseling, and HIV testing," Birnkrant said at a news conference held to announce the decision. "Truvada should not be used alone for HIV prevention."

Two major studies suggest that PrEP with Truvada may work as hoped:

• In the iPrEx study of 2,499 HIV-negative men and transgender women who have high-risk sex with men, those who took Truvada had 42% fewer HIV infections than those who did not. There was no evidence that taking Truvada increased unsafe sex, although study participants did not know for sure whether they were getting Truvada or an inactive placebo.
• The Partners PrEP study enrolled 4,758 heterosexual couples in which one member was infected with HIV and one was not. Truvada reduced the risk of HIV infection by 75%.

In the real world, however, it is not at all clear whether people who take Truvada will also take more risks, such as having sex without condoms or having multiple sex partners.

Moreover, Truvada must be taken every day in order to help prevent HIV infection. People in clinical trials did this. But if that doesn't happen in the real world, people who get infected while taking too few doses likely will end up with drug-resistant HIV infection that they can then spread to others.

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