A Randomized, Double-Blind Active-Controlled, Dose-Ranging Study of the Safety and Efficacy of Chronically Administered MDL 28,574A in the Treatment of HIV-Infected Patients

Inclusion Criteria Concurrent Medication: Allowed: Prior antiretroviral agents for up to 6 months per agent. Patients must have: HIV infection. Asymptomatic or mildly symptomatic. CD4 count 301 - 500 cells/mm3. Exclusion Criteria Co-existing Condition: Patients with the following condition are excluded: Unable or unwilling to comply with study procedures. Concurrent Medication: Excluded: Chemoprophylactic therapy for mycobacterial infection. Any nonstudy prescription medications without approval of investigator. Patients with the following prior conditions are excluded: History of grade 3 or 4 toxicity to <= 600 mg/day AZT. History of intolerance to lactose. Chronic diarrhea within 6 months prior to study entry. Unexplained intermittent or chronic fever, defined as temperature >= 38.5 C for any 7 days within the 30 days prior to study entry. Prior Medication: Excluded: Antiretroviral therapy within 2 weeks prior to study entry. Prior HIV vaccines. Biological response modifiers within 30 days prior to study entry. Prior foscarnet. Any investigational drug with a washout < 5 half-lives prior to study entry. Any medications known to alter renal, hepatic, or hematologic / immunologic function (such as barbiturates, phenothiazines, cimetidine, immunomodulators, etc.) within 14 days prior to study entry. Recent history of alcohol and/or drug abuse.