A Study of Azithromycin in the Prevention of Mycobacterium Avium Complex Disease (MAC) in HIV-Infected Patients

Inclusion Criteria Concurrent Medication: Required: Anti-pneumocystis prophylactic therapy (dihydropteroate synthetase inhibitors with or without dihydrofolate reductase inhibitors, pentamidine). Allowed: Concomitant anti-HIV therapy (AZT, ddI, ddC) or antifungal therapy (including azoles). Patients must have: HIV infection. CD4 count < 100 cells/mm3. No MAC positive blood cultures within 1 month prior to study entry. No symptoms suggestive of disseminated MAC infection (including unexplained diarrhea, fever, and night sweats) within 1 month of study entry. Exclusion Criteria Co-existing Condition: Patients with the following symptoms or conditions are excluded: Positive PPD within 3 months prior to study entry (negative PPD defined as < 5 mm induration). Chest x-ray suggestive of any active disease, in particular tuberculosis. Known hypersensitivity to macrolide antibiotics. Any other acute clinical condition likely to interfere with completion of the protocol. Inability to care for self without considerable assistance and medical care. Concurrent Medication: Excluded: Other investigational new drugs (except for foscarnet or ddC) unless prior agreement has been reached between the investigator and the Pfizer project physician. Concomitant putative immunostimulants. Patients with the following prior conditions are excluded: History of MAC or Mycobacterium tuberculosis (MTb) infection. Prior Medication: Excluded within the past 4 weeks: Any putative anti-MAC therapies including rifampin, rifabutin, clofazimine, ethambutol, cycloserine, ethionamide, amikacin, and ciprofloxacin or other quinolones thought to be active against MAC.