Potent drug therapies can suppress HIV to barely discernible levels in most people infected with the virus that causes AIDS -- even those who have failed other regimens, according to new HIV treatment guidelines.

In many instances, the recommendations of the International AIDS Society-USA Panel, released here at the International AIDS Conference, reflect only subtle changes from the group’s 2004 guidelines.

But one major departure from years past is that “we can now hit a home run” even when one or more drug regimens stop working, says panel member Stefano Vella, MD, of the Istituto Superiore di Sanita in Rome.

For people started on new drugs after treatment failure, the goal is to drive the virus to undetectable levels, defined as fewer than 50 copies per milliliter of blood, says panel head Scott M. Hammer, MD, chief of the division of infectious diseases at Columbia University College of Physicians and Surgeons in New York City.

In the past, the panel recommended only that treatment decrease HIV levels by a factor of 10.

The new regimen should include at least two and perhaps three new drugs, Hammer says. “Studies show that success is relative to the number of new agents.”

22 Anti-HIV Drugs Now Available

The release of the recommendations of the 16-member panel coincide with the 25th anniversary of initial reports of what the world would come to know as the acquired immune deficiency syndrome.

Since then, AIDS has grown to pandemic proportions, resulting in 25 million deaths worldwide. Another 40 million people around the globe are living with HIV infection.

This year also marks the 10th anniversary of what doctors call highly active antiretroviral therapy, or HAART -- potent drug cocktails credited with transforming HIV from a death sentence into a chronic manageable disorder, like diabetes.

“We now have 22 drugs in five different drug classes to choose from when caring for our patients,” Hammer says.

Since the last guidelines were published, two new protease inhibitors -- Aptivus and Prezista -- were approved by the FDA. Their approval, combined with the continued refinement of older drug regimens, provided the rationale for creating the new guidelines, he tells WebMD.

Less AIDS Monitoring Needed

As before, the guidelines call for initiating antiviral therapy in any person who develops symptoms of AIDS or whose CD4 cell count ---- the number of CD4 T-cells, which is a measure of how much damage HIV’s effect on the has done to immune system -- drops below 200 cells/microliter. The lower the CD4 cell count, the more susceptible a person is to infections. It should also be considered, with the decision individualized, for any person without symptoms whose CD4 count is between 200 and 350 cells/microliter.

“But if you read between the lines, we say maybe start earlier” and increase the strength of therapy as the CD4 count drops, Vella says. The researchers point out one study which showed a benefit to starting treatment when CD4 counts were above 350 cells/microliter.

The guidelines continue to recommend starting people newly infected with HIV on a three-drug cocktail of the oldest class of HIV drugs -- called nucleoside reverse transcriptase inhibitors -- combined with either a non-nucleoside reverse transcriptase inhibitor or a protease inhibitor. But once treatment starts, "we suggest doing a little less monitoring than was advocated in the past," Vella tells WebMD. "It's getting a little psychotic," with some people coming in every few days to find out if their drugs are suppressing the virus, she says.

The guidelines now suggest that HIV blood levels be checked every four to eight weeks until the virus is undetectable and then only three to four times a year.CD4 counts should be checked along with HIV blood levels.

Roy M. Gulick, director of the HIV Clinical Trial Unit at the New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City, tells WebMD he welcomes the new guidelines.

“Given the amount of information available and the continuing progress being made by the research community, it’s really a challenge to keep up with all the innovations,” he says. The guidelines streamline the process, “giving a really good sense of the field and helping to move treatment forward,” Gulick says.

The guidelines also appear in a special issue ofThe Journal of the American Medical Association.

By Charlene Laino, reviewed by Louise Chang, MD

SOURCES: XVI International AIDS Conference, Toronto, Aug. 13-18, 2006. Roy M. Gulick, director of the HIV Clinical Trial Unit at the New York-Presbyterian Hospital/Weill Cornell Medical Center. Scott M. Hammer, MD, chief, division of infectious diseases, Columbia University College of Physicians and Surgeons, New York City.