Merck’s new combination therapy for lowering elevated IOP in open-angle glaucoma or ocular hypertension patients who are insufficiently responsive to beta-blockers is now available, according to the company.
Cosopt PF (dorzolamide hydrochloride-timolol maleate ophthalmic solution) is a fixed-dose carbonic anhydrase inhibitor with a beta-adrenergic receptor blocking agent, according to a letter Merck sent to health care professionals. The treatment, approved Feb. 1 by the U.S. Food and Drug Administration, is Merck’s preservative-free formulation of Cosopt.
A study has shown Cosopt PF provides the same efficacy as original Cosopt, the letter said. An active-treatment controlled, parallel, double-masked analysis of 261 patients with IOP of 22 mm Hg or higher in one or both eyes showed Cosopt PF had an IOP-lowering effect equal to Cosopt.
The IOP-reducing impact of Cosopt twice daily was 1 mm Hg to 3 mm Hg greater than that of monotherapy with either 2% dorzolamide three times daily or 0.5% timolol twice daily, the letter said. The pressure-lowering effect of Cosopt twice daily was approximately 1 mm Hg less than that of concomitant therapy with 2% dorzolamide three times daily and 0.5% timolol twice daily.