A parallel, randomized, double-masked, active-controlled, multicenter study of patients with elevated IOP compared COSOPT to the concomitant administration of timolol and dorzolamide.¹ Following a 2-week run-in period with 0.5% timolol bid, 242 patients with IOP >22 mmHg were randomized to receive, for 3 months, either COSOPT bid (n=121) or concomitant administration (n=121) of 0.5% timolol bid and 2.0% dorzolamide tid. In an open-label extension, 220 patients received COSOPT bid for up to 9 months. Patient sample size for Months 3, 6, 9, and 12 reflects just those patients who exclusively received COSOPT for the entire 12 months.

• 242 patients enrolled. 9% (n=22) discontinued during the masked phase. 91% (n=220) stayed on therapy through the masked phase to enter the open-label extension¹
• IOP measurements taken at 21 different time points (Hours 0, 2, and 8 on Days 1, 15, 30, 60, and 90; Hours 0 and 2 on Days 180, 270, and 365)¹
• Low discontinuation rate (only 8%) during the 9-month open-label extension¹

COSOPT is indicated for the reduction of elevated intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension who are insufficiently responsive to beta blockers (failed to achieve target IOP determined after multiple measurements over time). The IOP-lowering effect of COSOPT bid was slightly less than that seen with the concomitant administration of 0.5% timolol bid and 2.0% dorzolamide tid.

COSOPT is contraindicated in patients with (1) bronchial asthma; (2) a history of bronchial asthma; (3) severe chronic obstructive pulmonary disease (see WARNINGS); (4) sinus bradycardia; (5) second- or third-degree atrioventricular block; (6) overt cardiac failure (see WARNINGS); (7) cardiogenic shock; or (8) hypersensitivity to any component of this product.

COSOPT contains dorzolamide, a sulfonamide, and timolol maleate, a beta-adrenergic blocking agent; and although administered topically, is absorbed systemically. Therefore, the same types of adverse reactions that are attributable to sulfonamides and/or systemic administration of beta-adrenergic blocking agents may occur with topical administration. For example, severe respiratory reactions and cardiac reactions, including death due to bronchospasm in patients with asthma and, rarely, death in association with cardiac failure, have been reported following systemic or ophthalmic administration of timolol maleate.

The concomitant use of 2 topical beta-adrenergic blocking agents (eg, COSOPT and any topical beta-adrenergic blocking agent) is not recommended.

In clinical trials with COSOPT, the most frequently reported adverse events were taste perversion (bitter, sour, or unusual taste) or ocular burning and/or stinging in up to 30% of patients. Conjunctival hyperemia, blurred vision, superficial punctate keratitis, or eye itching were reported in 5% to 15% of patients. A comprehensive list of adverse events observed in clinical studies and postmarketing surveillance is included in the Prescribing Information.

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