A Study of Foscarnet in the Treatment of Cytomegalovirus (CMV) of the Eyes in Patients With AIDS Who Have Not Had Success With Ganciclovir

Inclusion Criteria Concurrent Medication: Allowed: * Ganciclovir. Exclusion Criteria Co-existing Condition: Patients with the following are excluded: * Known allergy to foscarnet. * Any clinically significant pulmonary or neurologic impairment (e.g., patients who are intubated or comatose). * Corneal, lens, or vitreous opacification which precludes examination of the fundi in patients with cytomegalovirus (CMV) retinitis. Concurrent Medication: Excluded: * Acyclovir. * Nephrotoxic agent. Patients with the following are excluded: * Known allergy to foscarnet. * Any clinically significant pulmonary or neurologic impairment (e.g., patients who are intubated or comatose). * Corneal, lens, or vitreous opacification which precludes examination of the fundi in patients with CMV retinitis. Prior Medication: Excluded within 7 days of study entry: * Immunomodulators. * Biologic response modifiers. * Investigational agents. AIDS patients experiencing cytomegalovirus (CMV) retinitis may be enrolled if they meet one of the following criteria: * Myelosuppression: * Previously suffered severe dose-limiting ganciclovir-related myelosuppression, or are ineligible for ganciclovir treatment due to myelosuppression. * Ganciclovir treatment failure: * Clearly failed to have a therapeutic response to ganciclovir therapy. * Patients must be able to give informed consent. * Patients presenting with a baseline absolute neutrophil count \< 750 cells/mm3 or baseline platelet count \< 50000 platelets/mm3 will be categorized as ineligible to receive ganciclovir induction therapy and will be allowed to enter the study. * Patients who enter the study because of ganciclovir toxicity will have received ganciclovir therapy which resulted in either absolute neutrophil count falling to \< 750 cells/mm3 or platelet count falling to \< 50000 platelets/mm3 on two separate occasions during either 1\) a ganciclovir induction regimen of 7.5 mg or less ganciclovir/kg/day in divided doses or 2) a maintenance regimen of 5 mg or less ganciclovir/kg/day as a single dose. * Patients who enter the study because of ganciclovir treatment failure will meet one of the following criteria: * 1\) CMV retinitis progression as defined in section V.C.1., i.e., has occurred either at the end of a 10 - 21 day induction course of ganciclovir (7.5 - 10.0 mg/kg/day in divided doses) or 2) during the first 28 days of maintenance ganciclovir therapy (5 or more mg/kg/day in at least 5 days/week) where maintenance therapy began within 1. week of completing induction therapy.