Brimonidine 0.2% given two or three times daily versus timolol maleate 0.5% in primary open-angle glaucoma

PURPOSE: To evaluate the efficacy and safety of brimonidine 0.2% two or thr ee times daily versus timolol maleate 0.5% solution twice daily, METHODS: Patients with primary open-angle glaucoma were randomized by Latin square technique to one of the three treatment sequences in this crossover , prospective double-masked trial. Each treatment period consisted of 6 wee ks of chronic dosing followed by a diurnal curve for the intraocular pressu re measured at 08:00, 10:00, 16:00, 18:00, 20:00, 22:00, and 24:00 hours, I ntraocular pressure was measured by applanation tonometry. RESULTS: Thirty patients completed this trial, The average diurnal intraocu lar pressures in the trial were measured for timolol maleate (17.7 +/- 2.7 mm Hg), brimonidine given three times daily (18.0 +/- 2.2 mm Hg), and brimo nidine given twice daily (19.2 +/- 2.4 mm Hg), There was a statistical diff erence between groups (P < .005). When groups were compared by pairs, three times daily dosing with brimonidine and timolol maleate both reduced the p ressure more than twice daily brimonidine at every time point past 10:00 ho urs and for the diurnal curve (P < .05). In contrast, three times daily bri monidine and timolol maleate were statistically similar for the diurnal pre ssure, and each time point, except timolol maleate, decreased the pressure more at 16:00 (P = .042). Safety was similar between groups, CONCLUSIONS: This study demonstrated that both timolol maleate twice daily and brimonidine three times daily provide a similar intraocular pressure re duction to each other. Timolol maleate twice daily and brimonidine three ti mes daily provide a greater decrease in pressure in the late afternoon and nighttime hours, compared with brimonidine twice daily. (Am J Ophthalmol 20 01;131: 729-733. (C) 2001 by Elsevier Science Inc. All rights reserved.).