Comparison of Anti HIV Drugs Used Alone or in Combination With Cytosine Arabinoside to Treat Progressive Multifocal Leukoencephalopathy (PML) in HIV-Infected Patients

Inclusion Criteria Concurrent Medication: Allowed: * Local intralesional chemotherapy for mucocutaneous Kaposi's sarcoma. * Topical antifungals, clotrimazole, ketoconazole, fluconazole, and amphotericin B for treatment of mucosal and esophageal candidiasis. * Foscarnet for newly developed CMV infection, only after discussion with the protocol chair. * Prophylactic and maintenance therapy for other opportunistic infections, provided patients are considered clinically stable. * No more than 1000 mg/day acyclovir for herpes simplex. * Antibiotics for bacterial infections as clinically indicated. * Antipyretics, analgesics, and antiemetics. Concurrent Treatment: Allowed: * Local radiation therapy for mucocutaneous Kaposi's sarcoma. Patients must have: * HIV infection. * Confirmed PML. * No other current active opportunistic infections requiring systemic therapy. * Life expectancy of at least 3 months. NOTE: * A durable power of attorney is recommended where severe neurologic or psychiatric impairment can be foreseen while the patient is on study. Exclusion Criteria Co-existing Condition: Patients with the following symptoms or conditions are excluded: * Current active cryptococcal meningitis, cytomegaloviral encephalitis, toxoplasmosis encephalitis, CNS lymphoma, or neurosyphilis. NOTE: * Patients on maintenance therapy for cryptococcal meningitis or toxoplasmosis encephalitis that has been stable for 4 months are permitted. * Conditions that seriously increase risk of a surgical procedure (e.g., coagulopathy, severe thrombocytopenia). * Any other disease that would interfere with evaluation of the patient. * Other life-threatening complications likely to cause death in \< 3 months. Concurrent Medication: Excluded: * Ganciclovir. * Interferon. * Systemic chemotherapy other than Ara-C (unless specifically allowed). * Antiretroviral medications other than AZT, ddI, or ddC. Patients with the following prior conditions are excluded: History of allergy or intolerance to G-CSF. Prior Medication: Excluded: * Any prior Ara-C. Excluded within 14 days prior to study: * Ganciclovir or foscarnet. * Interferon. * Antiretroviral medications other than AZT, ddI, or ddC. * Experimental medications for treatment of PML.