Importance: This study evaluates the contribution of the individual components of an investigational non-β-antagonist fixed combination of brinzolamide, 1%, and brimonidine, 0.2%. This study and its sister study provide the first randomized data showing the intraocular pressure (IOP)-lowering activity and the toxicity profile of this novel topical antihypertensive fixed combination.
Objective: To compare IOP-lowering efficacy of fixed-combination brinzolamide, 1%, and brimonidine, 0.2%, with that of its components in patients with open-angle glaucoma or ocular hypertension.
Design: In this phase 3, double-masked, parallel-group, multicenter study, eligible patients were randomized 1:1:1 to treatment with fixed-combination brinzolamide, 1%, and brimonidine, 0.2%; brinzolamide, 1%; or brimonidine, 0.2%, 3 times daily for 3 months.
Setting: Sixty-six academic and private practice study sites throughout the United States.
Participants: A total of 660 adults with a clinical diagnosis of open-angle glaucoma or ocular hypertension from a referred sample were enrolled. Thirty-four patients discontinued participation due to treatment-related nonserious adverse events.
Intervention: Topical administration of study medication (fixed-combination brinzolamide, 1%, and brimonidine, 0.2%; brinzolamide, 1%; or brimonidine, 0.2%) 1 drop 3 times daily for 3 months.
Main outcomes and measures: Mean IOP at the 3-month visit at all time points (8 AM, 10 AM, 3 PM, and 5 PM).
Results: A total of 660 patients were enrolled. Baseline mean IOP values were similar among treatment groups at all 4 time points. At 3 months, the mean IOP of the brinzolamide-brimonidine group (16.3-19.8 mm Hg) was significantly lower than that of either the brinzolamide group (19.3-20.9 mm Hg; P ≤ .002) or the brimonidine group (17.9-22.5 mm Hg; P < .001) across all time points. One of 10 serious adverse events (chest pain, brinzolamide group) was judged as treatment related. A total of 129 patients experienced at least 1 treatment-related adverse effect (brinzolamide-brimonidine, 22.9%; brinzolamide, 18.6%; and brimonidine, 17.3%; P = .31), most of which were ocular.
Conclusions and relevance: This registrational study provides evidence that the fixed combination of brinzolamide, 1%, and brimonidine, 0.2%, can safely and effectively lower IOP in patients with open-angle glaucoma or ocular hypertension, showing significantly superior IOP-lowering activity compared with either brinzolamide or brimonidine monotherapy while providing a safety profile consistent with that of its individual components.
Trial registration: clinicaltrials.gov Identifier: NCT01297517.