An unidentified subject, who is HIV positive, reacts to the news of the drug Truvada for treatment of HIV. (Baltimore Sun photo by Kenneth K. Lam / July 17, 2012)

Sexual promiscuity fueled by alcohol and drug use led one 47-year-old Towson man to contract HIV.

But when he heard about government approval of the drug Truvada to lower people's risk of getting the disease, he wasn't completely sold on it as a lifesaver. The man, who didn't want to be identified because he hasn't told some family members he is HIV-positive, worries that such a pill could end up encouraging risk-taking.

"If you're going to make something readily available to people that already engage in high-risk behavior, are you not saying then that we condone this high-risk behavior, which will then add fuel to the fire?" he asked.

It's a common sentiment expressed by many medical professionals about Truvada, approved by the U.S. Food and Drug Administration this week as the first ever preventive drug for HIV.

Many in Maryland's public health community welcomed the drug but said it would not be a panacea in a city still in the grip of the epidemic, as it likely would not be widely prescribed because of the cost and side effects. They also warn the new preventive use for Truvada may give a false sense of security and make people more vulnerable to contracting HIV. And if the daily pill regimen isn't followed correctly, it could eventually lead to drug resistance.

The Towson man takes Truvada — on the market to treat HIV since 2004 — as part of his daily drug cocktail to treat his HIV and doesn't know if he would have stuck with a strict daily dose before contracting the virus. He and health officials say the fear is that those at risk will falter and stop using condoms to protect themselves.

"It's always good when new medications come out that can improve the quality of people's lives," said Dr. Oxiris Barbot, Baltimore's health commissioner. "My concern is that this is not going to be a cure-all for all people at risk for HIV. … The population driving the epidemic is not necessarily the one that is going to be utilizing Truvada to the greatest extent."

Others echoed Barbot's hopes and concerns about who will get the preventive medicine.

It won't be used in developing countries, for instance, because of the costs, said Dr. Robert C. Gallo, director of the Institute of Human Virology at the University of Maryland School of Medicine. And many in places such as Baltimore are uninsured and may not have access. The cost of the drug is estimated between $7,000 and $12,000 annually.

And side effects such as kidney and bone problems could keep others from using Truvada.

Drug maker "Gilead has done a great thing and for certain people and certain settings I am sure it can be beneficial," said Gallo, who is credited as co-discoverer of HIV as the cause of the AIDS virus in 1984. His research now focuses on an HIV preventive vaccine, lowering the level of infection in those with the virus and bringing drug therapy to underdeveloped nations.

Still, public health officials such as Gallo, as well as HIV/AIDS activists and patients, said Truvada was a welcomed advance for the nation and the state.

Maryland had one of the highest numbers of new cases in 2009, at 1,134 cases, according to the most recent data fromU.S. Centers for Disease Control and Prevention. More than 36,000 people in the state are now living with the virus.

Nationally, about 1.2 million people are living with HIV, and about 20 percent don't know they are infected, potentially passing the virus onto their partners, public officials say.

In Baltimore, which has the state's highest rate of infection, there were just over 400 new cases in 2010, or about 28 percent of all new cases that year in the state, according to the latest statistics available.

New cases are rising fastest among men who have sex with men. The percentage of new infections in Baltimore is now dominated by this group, while the numbers are dropping among other at-risk groups such as IV drug users, according to city data.

City officials have been targeting residents at-risk for infection with advertising campaigns and aggressive efforts at testing. City workers now plan to target the Mount Vernon club scene.

Other officials agree that vigilance in testing and condom use is crucial to stemming the infection rate.

Treatment, largely paid for with federal funding, has made medications widely available — Baltimore receives about $20 million annually for treatment — that has extended life expectancies. But that made some at-risk people too comfortable, said Dr. Joel Gallant, an infectious disease specialist and professor at the Johns Hopkins University School of Medicine and associate director of the AIDS Service at Hopkins Hospital.