Comparison of ocular hypotensive effect and safety of brinzolamide and timolol added to latanoprost

PURPOSE: To compare the ocular hypotensive effect and safety of brinzolamide and timolol added to latanoprost monotherapy. METHODS: In prospective randomized fashion, we evaluated the ocular hypotensive effect and safety of brinzolamide or timolol in 1 eye of 32 patients with primary open-angle glaucoma, normal-tension glaucoma, or ocular hypertension who had been treated with latanoprost for more than 1 month. Intraocular pressure (IOP), blood pressure, and pulse were measured before and at 4, 8, and 12 weeks. Corneal endothelial cell density was measured at baseline and at 12 weeks. RESULTS: The IOP was 17.8+/-1.7 mm Hg (mean+/-SD) before the addition of brinzolamide (n=15) and 15.7+/-2.1 mm Hg at 12 weeks (P<0.01). In comparison, the IOP was 18.5+/-3.7 mm Hg before the addition of timolol (n=15) and 15.8+/-3.2 mm Hg at 12 weeks (P<0.01). Both brinzolamide and timolol significantly decreased IOP at 12 weeks, by a mean of 2.0 mm Hg and mean 2.7 mm Hg, respectively, and were more effective than latanoprost alone (P<0.01), but there were no significant differences between the drugs and no significant differences in corneal endothelial cell density and blood pressure before and after addition of either drug. At 12 weeks, pulse was decreased in patients receiving timolol (P<0.01). As systemic adverse events, there was one instance of malar flushing after brinzolamide addition and episodes of chest discomfort after timolol addition in 1 patient. Ocular adverse events were slight. CONCLUSIONS: Brinzolamide and timolol added to latanoprost have similar ocular hypotensive effects and safety in primary open-angle glaucoma, normal-tension glaucoma, or ocular hypertension.