A Study of Foscarnet in the Treatment of Cytomegalovirus (CMV) of the Eyes in Patients With AIDS Who Cannot Use Ganciclovir

Inclusion Criteria Concurrent Medication: Allowed if hematologically stable on that regimen for at least 30 days prior to study entry: * Oral antibiotics. * Chemotherapy for Kaposi's sarcoma. * Acyclovir for outbreaks of herpes simplex or shingles. * Zidovudine (AZT), either initiated or continued, by patients randomized to both treatment arms. AZT given concurrently with foscarnet may be administered at a dose of 100 or 200 mg every 4 hours (q4h) at the investigator's discretion. Patients randomized to the delayed treatment arm may initiate or continue AZT administration at a dose of 100 or 200 mg q4h at the investigator's discretion. AZT may not be administered during the first 3 weeks of foscarnet therapy. Patients randomized to immediate therapy may begin or resume AZT when they enter the 2nd week of maintenance therapy (week 4 of the 10-week study period), if their hemoglobin is = or \> 8 g/dl and absolute neutrophil count is = or \> 1000 cells/mm3 at that time. Caution should be used in the concurrent use of foscarnet and ciprofloxacin, as such use has appeared to exacerbate renal failure in one patient. Patients must have active AIDS-related cytomegalovirus (CMV) retinitis as identified by its characteristic ophthalmoscopic appearance and verified by fundus photography. Patients must also demonstrate one of the following clinical and/or laboratory findings: * Treatment with ganciclovir (DHPG) resulting in dose-limiting toxicity (absolute neutrophil count (= polymo…