A Study of the Safety and Effectiveness of Combination Anti-HIV Therapy in HIV-Infected Adults

Inclusion Criteria Patients may be eligible for this study if they: Are HIV-positive. Have HIV levels of 50,000 copies/ml or more within 21 days prior to starting treatment. Are at least 18 years of age. Are willing to use an effective method of birth control during the study. (This study has been changed. A CD4 cell count of 50/mm3 or more within 21 days prior to starting treatment is no longer required.) Exclusion Criteria Patients will not be eligible for this study if they: Are pregnant. Have AIDS. Cannot take medications by mouth. Have hepatitis and it is active. Are enrolled in other investigational drug studies. Are allergic to any of the study drugs. Have a serious medical condition, such as heart disease. Have ever taken certain anti-HIV drugs such as nonnucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs). Have ever had more than 7 days of treatment with a nucleoside reverse transcriptase inhibitor (NRTI). Patients should have no prior treatment with abacavir and no prior treatment with at least one of the following: lamivudine or zidovudine. Have had radiation therapy or chemotherapy within 4 weeks prior to study entry, or plan to have such therapy during the study. Have received medications that might affect the immune system, such as systemic corticosteroids, interleukins, vaccines, or interferons within 4 weeks prior to study entry. Have received an HIV vaccine within 3 months prior to study entry. Are taking foscarnet, hydroxyurea, or other drugs that work against HIV. Have taken certain medications such as astemizole, cisapride, dihydroergotamine, ergotamine, ganciclovir, interferon-alpha, midazolam, terfenadine, and triazolam within 21 days of study entry. Abuse alcohol or drugs. Are unable to complete the whole study.