The lifetime cost of treating one person diagnosed with the AIDS virus has been estimated at more than $600,000.
"It's much more cost-effective to prevent a new infection than it is to treat someone for their lifetime," Loduca said. "Of course, the ultimate goal is a vaccine and a cure, but we're many years away from that."
Some of the more serious complications linked to Truvada include kidney and liver problems. But for some people, the risk of kidney problems "10 years down the line may be less than the risk for acquiring HIV, which is significantly more problematic and can be fatal," said Jim Pickett, director of prevention advocacy at the AIDS Foundation of Chicago.
Nick Literski, a government employee in Seattle, has been taking Truvada for HIV prevention for more than a year because his partner is infected. He said the drug has helped prevent the breakup of relationships like his.
"Many HIV-positive men end up ending their relationships with HIV-negative men out of fear of infecting their partner," Literski said.
AP Health Writer Matthew Perrone contributed to this story from Washington.
AP Medical Writer Lindsey Tanner can be reached at http://www.twitter.com/LindseyTanner
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