1) Informed consent and treatment randomization 2) Biochemical analysis: ALT, AST, total cholesterol and HDL, triglycerides 3) CD4 count, CD8 count 4) Plasma HIV-RNA 5) Clinical evaluation, anamnestic and demographic data: sex, age, risk factor for HIV infection, CDC AIDS classification, time on ART, time on current HAART, previous antiretroviral drugs, previous sub-optimal ARTs, current antiretroviral drugs, presence and grade of lipodystrophy, time with HIV-RNA below detection, nadir CD4, CD4 at start of antiretroviral therapy.