IDSA study offers good news for HIV care
A new protease inhibitor (PI) called atazanavir was found to actually improve the lipid profile of HIV patients in a 48-week study presented at the 40th Annual Meeting of the Infectious Diseases Society of America (IDSA), held in Chicago.
"Our most important conclusion is that therapy with a regimen that includes atazanavir is likely to have beneficial effects on lipid profiles as compared to other comparable PIs," says David Haas, MD, director of the Vanderbilt AIDS Clinical Trials Center and an associate professor of medicine at the Vanderbilt Medical School in Nashville, TN.
Haas was the lead author on a study that compared the total cholesterol from baseline and at 48 weeks following treatment with atazanavir.
Atazanavir has been submitted for approval by the Food and Drug Administration (FDA).
"This study was a head-to-head comparison of salvage therapy in patients with fairly early virologic failure," he says. "These were patients who had a good virologic response to previous potent regimens for at least 24 weeks, but were now failing therapy based on virologic criteria."
After treatment with atazanavir, HIV patients had a lipid profile that either did not change or actually improved, compared with an increase in abnormal lipids among the PI control group.1
While investigators wouldn’t want the study to be seen as evidence that atazanavir lowers pre-HIV treatment lipids, it is possible that since many of the patients already had experienced elevated lipids from previous antiretroviral therapies that the atazanavir treatment helped to improve these abnormal lipid profiles, Haas says.
"What makes this very important is that presently in clinical practice, treatment decisions in many situations are being driven at least as much, if not more, by toxicity considerations than by virologic and immunologic considerations," he adds. "For many patients in our clinic when we’re trying to choose a treatment regimen, the criteria for that regimen is [that it be] a potent regimen that does not affect lipids."
Investigators also found that patients receiving atazanavir, administered in once-daily doses along with saquinavir had comparable virologic responses as the control group of patients who received traditional PI and nucleoside reverse transcriptase inhibitor (NRTI) therapy, Haas explains.
Atazanavir is the only once-a-day PI administered without the boost of ritonavir, which has been associated with lipid abnormalities, he adds.
"Atazanavir dramatically boosts saquinavir levels and acts as an enhancer for saquinavir without boosting side effects," he says.
The fact that patients could take the atazanavir/ saquinavir combination as several pills once a day is another advantage to this option, he notes.
"I think it gives us one more option, which is very important given that therapy must be individualized for each patient," Haas says. "This drug will find use in patients who are treatment naïve where the use of a PI that may be given once a day and that’s well-tolerated would be attractive, and we’ll also find use in patients who have previously had other agents."
1. Sension M, Squires K, Cahn P, et al. Change in total cholesterol (as per NCEP ATP III) from baseline at 48 weeks following treatment with atazanavir or comparator protease inhibitors. Presented at the 40th Annual Meeting of the Infectious Diseases Society of America. Chicago; October 2002. Poster 468.