Purpose: The aim was to compare topical brinzolamide 1% twice daily with dorzolamide 2% twice daily, each given with timolol 0.5% twice daily, for safety and effects on intraocular pressure in patients with primary open-angle glaucoma or ocular hypertension.
Methods: This double-blind, randomized, active controlled, parallel group study was conducted multinationally at 31 sites, in 241 patients as above, with assessments at baseline and monthly during 3 months of treatment. The primary end point was a diurnal reduction of trough/peak intraocular pressure from a timolol 0.5% twice daily baseline.
Results: Both treatment regimens reduced intraocular pressure significantly at all time points (P <.001): brinzolamide plus timolol by -3.6 to -5.3 mm Hg (-14.2 to -21.9%), dorzolamide plus timolol by -3.6 mm Hg to -5.1 mm Hg (-14.1 to -21.2%). Clinically relevant intraocular pressure reductions (decreases 5 mm Hg or greater or absolute intraocular pressure values 21 mm Hg or less) were manifested by 50.0% to 89.3% of patients under brinzolamide plus timolol and by 43.9% to 85.4% under dorzolamide plus timolol. The treatments were equivalent in mean intraocular pressure-lowering. In general, both regimens were well tolerated. However, more patients (P =.001) experienced at least one adverse event with dorzolamide plus timolol (32.8%) as compared with brinzolamide plus timolol (14.7%); also, more patients (P =.001) experienced ocular discomfort (stinging and burning) after dorzolamide plus timolol (13.1%) than after brinzolamide plus timolol (1.7%).
Conclusions: In terms of intraocular pressure reduction, brinzolamide 1% twice daily was equivalent to dorzolamide 2% twice daily, each added to timolol 0.5% twice daily, but brinzolamide produced significantly less ocular burning and stinging.