Topical Dexamethasone γ-Cyclodextrin Nanoparticle Eye Drops increase Visual Acuity and decrease Macular Thickness in Diabetic Macular Edema

Abstract

Purpose: To test the efficacy and safety of topical 1.5% dexamethasone γ-cyclodextrin nanoparticle eye drops (dexNP) for diabetic macular edema (DME) and compare to posterior subtenon injection of triamcinolone acetonide.

Methods: This was a prospective, randomized controlled trial with 22 eyes in 22 consecutive patients with DME, who were randomized to a) topical treatment with dexNP eye drops x3/day for one month, x2/day the next month and finally x1/day the third month or b) one posterior subtenon injection of 20mg triamcinolone acetonide.

Results: The central macular thickness (CMT) decreased significantly with dexNP eye drops from 483±141mm to 384±142 mm at 4 weeks and 342±114 mm at 8 weeks. For triamcinolone, CMT decreased significantly at all time points. Visual acuity (logMAR) improved significantly with dexNP eye drops from 0.41±0.3 (mean±SD) to 0.32±0.25 and 0.30±0.26 at 4 and 8 weeks respectively. One third of the eye drop group improved more than 0.3 logMAR units. For triamcinolone, logMAR changed significantly from 0.42±0.28 at baseline to 0.32±0.29 at 4 weeks and 0.33±0.37 at 12 weeks. There was a modest increase in IOP at all time points with dexNP eye drops while no increase was seen with triamcinolone. Serum cortisol was affected by both treatments.

Conclusions: Topical dexamethasone γ-cyclodextrin nanoparticle eye drops significantly improve visual acuity and decrease macular thickness in patients with DME. The effect is similar to that from subtenon triamcinolone as well as to reports on intravitreal steroid implants and triamcinolone intravitreal injections. A modest increase in IOP was seen with the nanoparticle eye drops but IOP normalized after discontinuation of treatment.