Topical Interferon Gamma for Macular Edema Secondary to Uveitis

Objective: Information gathered from NEI laboratories suggests that cystoid macular edema (CME) is caused by the disequilibrium of the JakStat and mTor signal transduction pathways in the retinal pigment epithelium (RPE). We wish to investigate whether stimulating the JakStat pathway with topically applied interferon gamma-1b can be a therapeutic intervention for the treatment of CME secondary to uveitis. The objective of this study is to investigate the safety and efficacy of ocular instillations of interferon gamma-1b as a potential treatment for CME secondary to uveitis. Study Population: Five participants with CME as evidenced by OCT (\> 275 microns central macular thickness and/or loss of foveal contour) secondary to uveitis will receive topical ocular instillations of interferon gamma-1b. Up to seven participants may be enrolled in order to obtain the five participants to be included in the analysis if participants withdraw prior to receiving interferon gamma-1b. Design: This Phase I/II, non-randomized, prospective, uncontrolled, single-center study will involve instilling four drops of interferon gamma-1b (approximately 30 μg) topically on the cornea of the study eye four times a day for one week and measuring the potential response with optical coherence tomography (OCT). Outcome Measures: The primary outcome is the change in excess central macular thickening as measured by OCT in response to interferon gamma-1b. Treatment success is defined as a 25% decrease in excess central macular thickening at Week 1 as compared with baseline. Secondary efficacy outcomes include changes in macular volume as measured by OCT, visual acuity, intraocular pressure and intraocular inflammation as graded upon slit lamp examination. Secondary safety outcomes include ocular surface irritation assessed by fluorescein staining of the cornea and conjunctiva to assess toxicity, the number and severity of systemic and ocular toxicities, the number of adverse events and the proportion of participants with a visual loss of ≥ 15 Early Treatment Diabetic Retinopathy Study (ETDRS) letters.