The purpose of this study is to evaluate the safety and efficacy of a novel nucleoside sparing regimen containing atazanavir, ritonavir and efavirenz, using two different doses of atazanavir.

Inclusion Criteria:

• Provide written informed consent
• HIV positive with plasma HIV RNA viral load of ≥ 1000 copies/mL and CD4 cell count of ≥ 50 cells/mm3
• Antiretroviral (ARV) naive prior to enrollment
• Normal plasma triglycerides ≤ 200 mg/dL
• Women of child-bearing age must use effective barrier contraception

Exclusion Criteria:

• Pregnancy or breast feeding
• Evidence of resistance to antiretroviral drugs
• History of elevated blood cholesterol or triglycerides
• History of diabetes
• Hypersensitivity to any component of the study drugs
• Any cholesterol or triglyceride lowering medications in the past six months
• Use of growth hormone, megestrol acetate, or anabolic steroids in the past six months
• Imprisonment or involuntary incarceration for medical treatment