A Study of Different Doses of Atevirdine Mesylate Plus Zidovudine in HIV-Positive Patients

Inclusion Criteria Concurrent Medication: Allowed: * Primary or secondary prophylaxis for opportunistic infections. Patients must have: * HIV infection. * Symptoms (currently or prior to enrollment) included in Category B or C of CDC classification, although THE FOLLOWING CURRENT ACUTE MEDICAL CONDITIONS ARE NOT ALLOWED: * Cryptococcosis * Pneumocystis carinii pneumonia * Herpes zoster * Histoplasmosis * CMV * Hepatic or renal disease * Lymphoma. * CD4 count 50 - 350 cells/mm3 within 14 days prior to study entry. * Ongoing therapy with AZT at 500 - 600 mg total daily dose for at least 3 months prior to study entry. * Consent of parent, guardian, or person with power of attorney if less than 18 years of age. Exclusion Criteria Co-existing Condition: Patients with the following conditions are excluded: * Intolerance to AZT. * Current diagnosis of malignancy for which systemic therapy will be required during the study. Concurrent Medication: Excluded: * Any other investigational drugs. Prior Medication: Excluded: * Cytotoxic chemotherapy within 1 month prior to study entry. * Prior U-87201E or any other non-nucleoside antiretroviral medications, including but not limited to nevirapine, TIBO R-82150 or TIBO R-82913, L-697639 or L-696229, U-90152S, or any protease inhibitors. * Antiretroviral agents other than AZT within 3 months prior to study entry. Required: * AZT for at least 3 months prior to study entry. Present use of excessive alcohol or illicit drugs.