Clinical efficacy and safety of brinzolamide (Azopt), a new topical carbonic anhydrase inhibitor for primary open-angle glaucoma and ocular hypertension. Brinzolamide Primary Therapy Study Group.

PURPOSE

To determine the intraocular pressure-lowering efficacy and safety of brinzolamide 1.0%, compared with dorzolamide 2.0% and timolol 0.5%.

METHODS

A multicenter, double-masked, prospective, parallel-group study was conducted to compare brinzolamide 1.0%, administered two and three times a day, dorzolamide 2.0% three times a day, and timolol 0.5% twice a day in 572 patients with primary open-angle glaucoma or ocular hypertension. The primary end point was diurnally corrected intraocular pressure reduction from baseline, evaluated at both peak and trough times during a 3-month period.

RESULTS

Mean intraocular pressure changes after twice daily (-3.8 to -5.7 mm Hg) and three times daily (-4.2 to -5.6 mm Hg) dosing with brinzolamide 1.0% were statistically equivalent (confidence limit < or = 1.5 mm Hg) to each other and also to dorzolamide 2.0% three times a day (-4.3 to -5.9 mm Hg). The range of intraocular pressure change with timolol 0.5% twice daily was -5.2 to -6.3 mm Hg. Clinically relevant intraocular pressure changes (reduction > or = 5 mm Hg or intraocular pressure < or = 21 mm Hg) were observed in up to 75.7% of patients taking brinzolamide twice daily and in up to 80.1% taking brinzolamide three times daily. Treatment with brinzolamide 1.0% was safe, comfortable, and well tolerated. The incidence of ocular discomfort (burning and stinging) on instillation of brinzolamide (twice daily, 1.8%; three times daily, 3.0%) was significantly less (P = .000) compared with treatment with dorzolamide (16.4%).

CONCLUSIONS

Brinzolamide 1.0% produced clinically relevant intraocular pressure reductions in substantial numbers of patients. Brinzolamide's effectiveness equaled that of dorzolamide 2.0% and it produced less ocular discomfort (burning and stinging) on instillation.