gms | German Medical Science

Neuroprotection may be an option in ischemic optic nerve disease. There have been promising reports about the neuroprotective capacity of topical brimonidine in animal studies. Therefore we tested whether 0.2% brimonidine-tartrate could improve the outcome of patients with non-arteritic anterior ischemic optic neuropathy (NAION). The study was stopped after an interim analysis having not proven its feasibility within practicable time frame.

A three-months, double-blind, placebo-controlled, randomised European multicenter trial according to good clinical practice rules. 36 (22m, 14f) patients older 40 y with first eye involvement were included in the study within the first week after visual loss (VA 0.05 - 1.0) and had to show typical signs of NAION. Visual acuity (VA, primary endpoint), visual field (VF, Humphrey 30-2 and Goldmann, quantified by a modified Esterman grid) and automated swinging flashlight test (SWIFT) were done at baseline, 2 weeks, 4 weeks and 12 weeks after first visit. Primary analysis aimed at intention-to-treat group (ITT, n=29), secondary analysis to the per protocol population (PP, n=25). Tolerability and safety were tested in the safety group (n=36). A two-sample two-sided t-test was used for statistical analysis (alpha level at 0.05).

VA did not show statistically significant difference by treatment. There were non-significant trends for better visual field results in the brimonidine group. Adverse events consisting of local irritation were observed six times in the verum and three times in the placebo group. No serious adverse events occurred.

In contradiction to an open retrospective study published by Fazzone et al. (BJO 2003; 87:1193-4) the results of this trial did not hint at any harmful effect of brimonidine in patients suffering from NAION. The functional outcome could not be improved to a relevant and significant amount, although positive trends by brimonidine were observed for VA and both VF methods.