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

To compare the safety and efficacy of antiretroviral therapy (zidovudine plus either didanosine or dideoxycytidine) versus antiretroviral therapy plus intravenous cytarabine (Ara-C) versus antiretroviral therapy plus intrathecal Ara-C in the maintenance or improvement of neurological function over 6 months in HIV-infected individuals who have developed progressive multifocal leukoencephalopathy (PML). To compare the effect of these three treatment regimens on Karnofsky score and MRI studies. The effectiveness of Ara-C in the treatment of PML, caused by a human DNA papovavirus (designated JC virus) infection, has not been determined, although the most encouraging results have occurred with intrathecal administration of the drug.