A Study to Determine How and Why HIV-Infected Subjects on Anti-viral Treatment Develop Lipodystrophy

HIV infection is a major global health problem. Survival and quality of life for HIV subjects has tremendously improved with the advent of a class of antivirals called protease inhibitors and the utilization of highly active combination therapy. However, such therapy has been associated with a syndrome called lipodystrophy. This lipodystrophy syndrome causes body shape changes; typically thinning and loss of fat from the arms, legs and face, with increased fat appearing in the abdomen and neck. There are also metabolic changes which occur, and subjects can develop increased triglycerides, increased cholesterol and an increased risk for diabetes as indicated by increasing insulin resistance. This study will take HIV positive subjects who have not yet started antiviral medications (treatment naive)and randomly assign them to one of two treatment arms. These treatment arms will be: Sustiva/Zerit/Epivir vs. Viracept/Zerit/Epivir The subjects will be treated and followed for two years and have extensive metabolic testing, skinfold thickness measurements, MRI scans and other measures to determine if and how they are experiencing changes in metabolism or body shape and to discover the mechanism of why this occurs. Understanding the mechanism should allow researchers to design interventions for subjects who have lipodystrophy and strategies to prevent lipodystrophy from occurring to subjects treated with antivirals in the future.