A Study of the Effects of Amprenavir, a Protease Inhibitor, on Carbohydrate and Fat Metabolism in HIV-Infected Patients

Inclusion Criteria Patients may be eligible for this study if they: * Are HIV-positive. * Are at least 18 years old. * Have very little or no anti-HIV drug experience (see below for details) and have never taken ABC. * Have a CD4 count greater than or equal to 200 cells/mm3 within 30 days prior to study entry. * Have a viral load (level of HIV in the blood) greater than 500 copies/ml within 30 days prior to study entry. * Agree to use effective methods of birth control during the study. Exclusion Criteria Patients will not be eligible for this study if they: * Have taken both 3TC and stavudine (d4T). * Have taken a protease inhibitor (PI) or nonnucleoside reverse transcriptase inhibitor (NNRTI) for more than 7 days. * Have taken a PI within 60 days of study entry. * Have a history of diabetes. * Have a history of untreated gonad or thyroid disorder. * Have a stomach or intestinal disorder which may affect the way the body absorbs the study drugs, or which may make them unable to take medications by mouth. * Have received chemotherapy or radiation within 4 weeks prior to entry, or if they will need either of these during the study period. * Have lost or gained a significant amount of weight (greater than 5%) within the past 2 months. * Have a serious medical condition, such as heart disease. * Are allergic to any of the study drugs. * Have been treated for an infection or other medical illness within 14 days prior to study entry. * Have had a fever (over 38.5 degrees Celsius) for any 7 days or chronic diarrhea (more than 3 liquid stools per day for 15 days) within 30 days prior to study entry. * Have an AIDS-related cancer (other than Kaposi's sarcoma). * Abuse alcohol or drugs. * Have received certain medications. * Are pregnant.