By Carina Storrs
THURSDAY, July 19 (HealthDay News) -- The first glimmer of hope for a cure for HIV came in 1996 with the advent of powerful drug cocktails known as highly active antiretroviral therapy (HAART). But the feeling was short-lived.
While HAART has drastically reduced deaths due to AIDS and other HIV-related diseases, it is no cure -- if patients stop taking the medications (because of side effects or other reasons), the virus bounces right back, as a 2010 study of patients in Latin America and the Caribbean showed.
Yet, there is now a renewed sense of promise that, even if it still years away, researchers have a better understanding of targets that could lead to a cure, said Rowena Johnston, vice president and director of research at the Foundation for AIDS Research. "We are seeing something that is probably a lot like that time in the 1990s," she said.
In 2012, new causes for optimism include approval of a new drug, Truvada, that can help prevent the spread of HIV, safer and more effective drugs to treat those who are infected and better efforts to diagnose HIV/AIDS in people who don't realize they have it.
These and other achievements will be a focus at the biennial International AIDS Conference, held this year in Washington, D.C. The meeting, which begins Sunday, has not been held in the United States in 22 years. Its return stems from the Obama administration's decision in 2009 to end the ban on HIV-positive people entering the country, Johnston said.
Hints at a cure
Another "large part of the basis for the new optimism" comes from the experience of one patient back in 2008, Johnston said. That was Timothy Brown, also known as "the Berlin patient," who was pronounced cured of HIV by his doctors.
The cure involved a special kind of blood transplant that Brown received for his leukemia from a donor that happened to have rare, mutant cells that did not allow HIV to take hold. This procedure is "absolutely not practical" for the general population, Johnston said, but it has launched research looking at ways to mimic the effect, by using gene therapy to make a patient's cells resistant to HIV.
"[But] if we are going to bring about an 'AIDS-free generation,' as [then] Senator Hilary Clinton said, we are also going to need to decrease the number of new HIV cases and bring that number down to zero," Johnston said.
That's a lofty goal, since more than 1 million people in the United States remain infected with HIV, according to estimates by the U.S. Centers for Disease Control and Prevention. There are also about 50,000 new cases of HIV every year and that number hasn't budged over the past two decades.
"On the prevention side, the excitement is all around use of antiretroviral therapy," said Dr. Sten Vermund, director of the Vanderbilt Institute for Global Health in Nashville, Tenn.
For example, one 2011 study showed that treating patients with antiretroviral therapy early -- before HIV had weakened their immune system -- not only kept the patients healthier, it reduced the risk that their uninfected sexual partners would become infected by 96 percent. "That's as good as condoms," Vermund noted, although experts are quick to stress that no medication should be seen as a substitute for the condom.
Partly because of that study, the U.S. Department of Health and Human Services in March 2012 recommended that doctors prescribe antiretroviral therapy for all HIV patients, even if their immune system is strong, as long as they can commit to the daily medication regime.
Using treatment as prevention
Taking the use of antiretroviral therapy for prevention a step further, the U.S. Food and Drug Administration on Monday approved Truvada (an anti-HIV drug already used as treatment) for people uninfected with HIV but at high risk of becoming infected -- making it the first medication to help prevent infection.