Treatment of Cytomegalovirus Retinitis with Intravitreous Cidofovir in Patients with AIDS: A Preliminary Report

Background: Cytomegalovirus retinitis remains a major cause of illness in patients with the acquired immunodeficiency syndrome (AIDS), and existing therapies for this condition are relatively ineffective and toxic. Objective: To evaluate the efficacy of intravitreous cidofovir injections alone for initial and maintenance therapy for cytomegalovirus retinitis. Design: Prospective, nonrandomized, consecutive case series. Setting: University ophthalmology referral clinic. Patients: 22 patients with AIDS and cytomegalovirus retinitis. In 15 of 32 affected eyes, intravitreous cidofovir was administered as the initial treatment for cytomegalovirus retinitis (group A); 17 eyes had previously been treated with intravenous therapy (group B). Intervention: All eyes were intravitreously injected with 20 μg of cidofovir at 5- to 6-week intervals. No patient in either group received systemic anticytomegalovirus therapy at any time during the study period. Measurements: Healing of retinitis was defined as resolution of retinal opacification and cessation of border progression. Progression, the primary end point, was defined as 750 microns of border progression or development of a new lesion. Results: The mean duration of follow-up was 15.3 weeks (range, 5 to 44 weeks). Of the eyes with active retinitis, 100% (95% Cl, 87% to 100%) healed in response to the initial injection. In two eyes (6%; Cl, 0% to 15%), two episodes of retinitis progression occurred (one in each eye). Both of these eyes were in a patient with clinically resistant retinitis. In 3% of eyes (Cl, 0% to 9%), the retina became detached. Mild iritis developed after 14% of the injections that had been preceded by prophylaxis with oral probenecid. Irreversible, visually significant hypotonia developed in one eye. Conclusion: Treatment and subsequent maintenance of cytomegalovirus retinitis with 20 μg of intravitreously injected cidofovir, given at 5- to 6-week intervals, is safe and highly effective.