Efficacy of 0.5% Indomethacin Eyedrops in Uveitic Macular Edema: a Randomized, Double-blind, Placebo-controlled Clinical Trial

Abstract

Purpose: Cystoid macular edema as a secondary complication of different etiology uveitis, mainly intermediate and pan-uveitis, is one of the most important causes of visual impairment in developed countries. Systemic and topical NSAIDs showed efficacy in the prophylaxis and treatment of pseudophakic cystoid macular edema. The aim of the present randomized, double-blind, placebo-controlled clinical trial was to assess the efficacy and tolerability of 0.5% indomethacin eyedrops in adult patients affected by uveitic cystoid macular edema.

Methods: 46 eyes of 31 patients (20 females and 11 males), mean age 39y (range 24-78) affected by inflammatory refractory cystoid macular edema, were randomized to receive 0.5% indomethacin eyedrops (INDOM®, Alfa Intes, Italy) QID (16 subjects) or placebo (saline solution, 15 subjects) continuously during a six-month period. Visits were at baseline and at 1, 3 and 6 months. Primary endpoint was central foveal thickness reduction (Heidelberg Spectralis II OCT). Secondary endpoints were visual acuity, subjective symptoms (itching, burning, photofobia and watering, 0-3 points score) and central volume OCT measurement.

Results: After 6 months, central foveal thickness showed a significant decrease in treated patients by an average of 150 μ (p<0.0001, 180days vs baseline) compared to the placebo group in which no significant improvement of edema was seen (p=1, 180days vs baseline). More than 50% of eyes in the placebo group got worse after 180 days, compared to less than 10% in the treated group. Also visual acuity was significantly improved in treated eyes (p<0.0001, 180days vs baseline) and after 6 months there was a significant correlation between retinal thickness decrease and visual acuity increase (R=-0.35022, p=0.0170). Not all eyes showed a complete resolution because of central vitreo-retinal traction, frequently found in uveitic eyes. No significant difference in subjective symptoms was observed and no adverse event occurred except from one patient complaining of eye burning at instillation in the treated group.

Conclusions: Topical use of 0.5% indomethacin eyedrops in eyes affected by uveitic cystoid macular edema of different etiologies in comparison with placebo is associated with a significant reduction in macular edema after six months as measured by SD-OCT and an increase of visual acuity.

Keywords: 746 uveitis-clinical/animal model • 505 edema • 503 drug toxicity/drug effects