A Randomized, Comparative Trial of Zidovudine (AZT) Versus AZT Plus Didanosine (ddI) Versus AZT Plus Dideoxycytidine (ddC) in HIV-Infected Patients

Inclusion Criteria Required: Documented HIV infection OR working diagnosis of HIV OR evidence of idiopathic suppression with an AIDS-defining opportunistic infection or malignancy (except Kaposi's sarcoma). CD4+ cell count = or < 200/mm3 or = or < 15 percent of total lymphocyte count within previous 90 days OR history of AIDS-defining opportunistic infection. Current PCP prophylaxis. Exclusion Criteria Co-existing Condition: Patients with the following symptoms and conditions are excluded: Symptoms of pancreatitis or peripheral neuropathy of grade 2 or worse. Requirement for acute therapy for any active AIDS-defining opportunistic infection or systemic chemotherapy for malignancy. Stage 2 or worse (moderate) AIDS Dementia Complex. Other disorders or conditions for which the study drugs are contraindicated or that may prevent adequate compliance with study therapy. Concurrent Medication: Excluded: Acute therapy for active AIDS-defining opportunistic infection. Systemic chemotherapy for malignancy. Antiretroviral therapy other than that provided by this study. Patients with the following prior conditions are excluded: History of pancreatitis or peripheral neuropathy of grade 2 or worse. History of intolerance to the study drugs at entry doses and/or frequencies. History of phenylketonuria.