U.S. officials have approved what they say is the first drug on the market that reduces the risk of HIV infection in those who are free of the virus that causes AIDS.

The U.S. Food and Drug Administration Monday said the drug Truvada now can be used daily in combination with safer sex practices to reduce the risk of sexually acquired HIV infection in adults at high risk.

In a written statement, FDA Commissioner Margaret Hamburg said the agency's approval marks an important milestone in the fight against HIV. She added that every year, about 50,000 U.S. adults and adolescents are diagnosed with the infection.

Debra Birnkrant, director of the FDA's Division of Anti-viral Products, said the drug could help turn the tide of the HIV epidemic, but she stressed that the drug is reserved for a high-risk population.

“It will bring people in for testing. And in that way, if people test positive, then they can be treated for HIV. And that will help stem the epidemic.”

But some AIDS advocates say the drug is not safe. Michael Weinstein, president of AIDS Healthcare Foundation, warns that it can cause kidney damage and bone loss, and it might lead people to drop the use of condoms, which he says is a proven safe method of preventing infection.

“We don't expect people to use condoms once they are taking this medication. And if they take it inconsistently, they're going to think they are protected when they are not.”

Weinsten says the pill is a typical quick fix for people inclined to take the easy way out. But he warns that it may not work.

The FDA previously approved Truvada to be used in combination with other antiretroviral agents to treat HIV-infected adults and children 12 years and older.