The Effects of Topical Dorzolamide on Visual Acuity and Disease Progression in Non–Neovascular Age–Related Macular Degeneration: a One–Year, Randomized, Double–Masked, Placebo–Controlled Trial

Abstract

Abstract: : Purpose: Given the vasoactive suggestion of effects of dorzolamide on ocular blood flow, we evaluated the effects of topical dorzolamide on visual acuity and disease progression to neovascularization in patients with non–neovascular age–related macular degeneration (AMD) over a one year period Methods: Thirty–eight patients with non–neovascular AMD were examined in a randomized, double–masked, placebo–controlled trial. Visual acuity and disease assessment were obtained at baseline, and at 3, 6, and 12 months of topical treatment with 2% dorzolamide hydrochloride ophthalmic suspension (n=16) or placebo (n=22) TID. Best corrected visual acuity (BCVA) was measured using an ETDRS chart. Disease progression to the neovascular stage was assessed clinically and by fluorescein angiograms. A t–test was used to compare the change in BCVA from baseline to one–year between groups. Moderate (MVL) and severe visual losses (SVL) from baseline to follow–up visits and the progression to neovascular AMD were analyzed using a Fisher’s exact test. Results: Twenty eight patients (Mean age 74.2+/–6.5; 17 females; 17 on placebo, 11 on dorzolamide) completed the one–year follow–up. Five patients from each group discontinued the study for various reasons. Only one patient from the dorzolamide group dropped out due to drug–related side–effects (stinging). No significant differences were found in mean BCVA between the dorzolamide and placebo groups at baseline and at the 12–month visit (p=0.805 & p=0.399, respectively). Mean changes in BCVA from baseline to 12–month visit were not significantly different between groups (p=0.486). In each group, one subject had experienced SVL and none had MVL. Two of the 17 patients on placebo versus none of the 11 on dorzolamide developed choroidal neovascularization during the study period (P=0.505). Conclusions: This pilot study suggests that dorzolamide is safe among non–neovascular AMD patients. The finding that none of the patients in the dorzolamide group versus 2 in the placebo group have progressed to neovascular AMD during the study period requires further study.

Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled • drug toxicity/drug effects