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

Abstract

PURPOSE: To evaluate the efficacy and safety of brimonidine 0.2% two or three 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 weeks of chronic dosing followed by a diurnal curve for the intraocular pressure measured at 08:00, 10:00, 16:00, 18:00, 20:00, 22:00, and 24:00 hours. Intraocular pressure was measured by applanation tonometry. RESULTS: Thirty patients completed this trial. The average diurnal intraocular 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 brimonidine given twice daily (19.2 ± 2.4 mm Hg). There was a statistical difference between groups ( P < .005). When groups were compared by pairs, three times daily dosing with brimonidine and timolol maleate both reduced the pressure more than twice daily brimonidine at every time point past 10:00 hours and for the diurnal curve ( P < .05). In contrast, three times daily brimonidine and timolol maleate were statistically similar for the diurnal pressure, 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 reduction to each other. Timolol maleate twice daily and brimonidine three times daily provide a greater decrease in pressure in the late afternoon and nighttime hours, compared with brimonidine twice daily.