[Cidofovir (vistide) in therapy of progressive multifocal leukoencephalopathy in AIDS. Review of the literature and report of 2 cases].

The progressive multifocal leukoencephalopathy (PML), a complication of the acquired immunodeficiency syndrome (AIDS) in 4%-5% of all cases, is an encephalitis caused by the JC papovavirus. The prognosis is very poor with a mean survival time after diagnosis of 3 to 6 months. No effective therapy is known to date. Therapeutic trials in small groups of patients with alpha-interferon, didanosine, and arabinoside were of minor success. A controlled study with cytarabine did not show any efficacy. Single case reports on a therapy with cidofovir (Vistide), an approved nucleotide-analogone in the therapy of cytomegalovirus-retinitis in AIDS-patients without renal dysfunction, showed positive results. We describe 2 more cases of a therapy of cidofovir in AIDS-associated PML. Out of 22 cases described in the literature, including these 2 cases, with a therapy of cidofovir in AIDS-associated PML, 16 patients improved under therapy, 2 remained stable, and only 4 patients still worsened fulminantly. These results indicate an additive antiviral effect of cidofovir against JC-virus. This may be used in the therapy of PML in AIDS-patients because no alternative antiviral therapy of PML is available at present. The efficacy of cidofovir for the therapy of PML is suggested by case reports. The exact mechanisms leading to an improvement under a therapy with cidofovir in the 16 cases described so far should be evaluated in a randomised, controlled study with an adequate size of cohorts.