THE TREATMENT OF CHOROIDAL NEOVASCULAR MEMBRANES BY ALPHA-INTERFERON - AN EFFICACY AND TOXICITY STUDY

Purpose: The purpose of this phase 2 study was to determine the potent ial efficacy and safety of systemic alpha interferon in the treatment of subfoveal choroidal neovascularization associated with age-related macular degeneration or ocular histoplasmosis. Method: Subcutaneous al pha interferon was administered to 24 patients (24 eyes), and they wer e prospectively studied. Alpha interferon was administered subcutaneou sly four times daily at a dose of 3 X 10(6) U/m(2) (average total dose , 204 MU). The studied parameters included best-corrected visual acuit y, membrane size, blood, exudates, and subretinal fluid. Toxic effects and performance status were graded according to the National Cancer I nstitute toxicity criteria and Karnofsky performance scale, respective ly. Results: Of the 24 treated eyes, 5 (21%) showed objective evidence of anatomic improvement, as defined by decrease in membrane size or i mprovement in fluorescein angiographic characteristics, but in only 3 of these 5 was the improvement maintained. The same three patients ach ieved and maintained functional success (visual improvement). Two of t he five patients with initial anatomic improvement had subsequent memb rane recurrence, which resulted in no visual change in one but visual loss in the other. For the majority of patients, the anatomic and visu al status remained the same or became worse after treatment. All patie nts experienced some degree of adverse reactions involving multiple or gan systems. Decreased performance status affected 80% of the patients . Conclusion: This study documents that regression of choroidal neovas cularization that occurred with alpha interferon treatment was minimal . Toxic effects interfering with patients' performance status are asso ciated with alpha interferon treatment. Although a randomized trial of interferon versus no therapy may be warranted, fundamental issues (i. e., the biologic properties of interferon versus other more potent age nts against choroidal neovascularization, medication dosages, and rout es of administration, need to be addressed before embarking on such a trial.