New clinical trial data on the experimental HIV protease inhibitor atazanavir show that the drug is as effective as Viracept in suppressing HIV replication but does not appear to cause "clinically relevant" lipid increases. The study showed that when taken for 46 weeks, atazanavir produced little change in total cholesterol, LDL (or "bad" cholesterol), or triglyceride levels. In fact, some study participants had slight reductions of blood lipid levels. Elevated lipid levels are a common side effect of protease inhibitors and were seen among study participants taking Viracept in the current Bristol-Myers clinical trial. Both medications produced similar reductions in HIV viral loads and boosts in T-cell counts. Diarrhea was more common among study participants taking Viracept, while jaundice was observed among patients treated with atazanavir.
Atazanavir, developed by Bristol-Myers Squibb, is currently under review at the Food and Drug Administration and is expected to be approved later this year. It is the first protease inhibitor to be submitted with data aimed at winning approval for once-daily administration.