48-week data on atazanavir presented at the 8th European Conference on Clinical Aspects and Treatment of HIV-Infection [Athens, Greece; October 2001] show that this potent azapeptide inhibitor of HIV-1 protease has efficacy that is at least comparable to other protease inhibitors, but does not produce any significant alteration of lipid levels. Protease inhibitors have been implicated in the development of elevated cholesterol and/or triglycerides, which is of concern due to the potential for subsequent development of cardiovascular disorders or pancreatitis. This issue has become particularly important as the survival of patients with HIV infection improves as a result of advances in antiretroviral therapy, raising awareness of the longer-term effects of such therapy.