FDA approves combination glaucoma drop without beta-blocker

FDA approved a new fixed-dose combination ophthalmic suspension of a carbonic anhydrase inhibitor (brinzolamide 1.0%) and an alpha 2 adrenergic receptor agonist (brimonidine tartrate 0.2%), which is indicated for the reduction of intraocular pressure in patients with primary open-angle glaucoma or ocular hypertension.

Simbrinza Suspension, developed by Alcon, a division of Novartis, is the only fixed combination drop for glaucoma that is available in the U.S. without a beta-blocker, according to a company statement.

“The introduction of Simbrinza further expands our ability to provide effective treatments for patients with elevated IOP. Given its excellent efficacy, established safety profile, and the fact that it is the only available, fixed-dose combination without a beta-blocker approved in the U.S., Simbrinza has the potential to reshape the treatment paradigm for glaucoma,” said Robert Warner, area president, U.S. and Canada for Canada.

The approval of Simbrinza is based on data from two phase III clinical trials, enrolling 1,300 patients. The fixed combination of brinzolamide 1.0% and brimonidine 0.2% was compared to dosing of one or the other components, with all patients receiving the medications three times daily during the three-month studies.

In one of the studies, Gregory Katz, MD, and his colleagues enrolled 660 patients who had been diagnosed with open-angle glaucoma or ocular hypertension and randomly assigned them to one of three treatment groups (fixed-combination brinzolamide 1.0% and brimonidine 0.2%, brinzolamide 1.0%, and brimonidine 0.2%) to be dosed three times daily. Thirty-four patients discontinued treatment due to treatment-related side effects. At the end of the three-month study, the mean IOP of the fixed combination group (16.3-19.8 mm Hg) was significantly lower than either of the brinzolamide group (19.3-20.9 mm Hg; P≤.002) or the brimonidine group (17.9-22.5 mm Hg; P<.001). During the study, 129 patients experienced at least one treatment-related side effect, although most were ocular events.

In the second study, Quang Nguyen, MD, and his colleagues followed 690 patients with open-angle glaucoma or ocular hypertension for 3 months and again patients were randomized to the one of three groups (fixed combination or brinzolamide 1.0% or brimonidine 0.2%), at a dosing schedule of three times daily. At the end of three months, mean IOP of the fixed combination group was significantly lower than either the brinzolamide or the brimonidine group (P≤.005). Of the 615 patients who completed the study, 143 experienced at least one treatment-related side effect, with most being ocular side effects. The results were consistent with the other study.

The most frequently reported side effects in patients who received the fixed combination medication were blurred vision, eye irritation, dysgeusia, dry mouth, and eye allergy. Approximately 11% of the patients randomly assigned to Simbrinza discontinued treatment due to adverse effects, according to the Alcon statement.

“There were no significant cardiovascular or pulmonary events found with Simbrinza in either clinical study conducted,” Alcon reported.