FDA Approves Cosopt Pf (dorzolamide hydrochloride-timolol maleate ophthalmic solution) for reduction of elevated intraocular pressure in open-angle glaucoma or ocular hypertension.

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FDA Published April 14, 2026 Medically reviewed April 20, 2026 DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Consider for IOP reduction in glaucoma patients unresponsive to beta-blockers, with slightly less efficacy than separate concomitant therapy.

The FDA has approved Cosopt Pf (dorzolamide hydrochloride-timolol maleate ophthalmic solution), a preservative-free combination eye drop, for the reduction of elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension who are insufficiently responsive to beta-blockers. This approval provides a preservative-free option for patients who may require long-term therapy or have sensitivities to preservatives, potentially improving tolerability and adherence in this chronic condition. Clinically, the drug offers a fixed-dose combination that simplifies administration compared to using separate medications, though label data indicate its IOP-lowering effect is slightly less than that of concomitant therapy with individual timolol and dorzolamide components. The approval is based on clinical studies showing efficacy over monotherapies and equivalence to the preservative-containing version, with dosing set at twice daily.

＋ Clinical Details (Mechanism · Dosing · Trial Data · Warnings)

Mechanism of Action

Not reported in label.

Indication & Patient Population

Dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) 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).

Dosing & Administration

The dose is one drop of dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) in the affected eye(s) two times daily. If more than one topical ophthalmic drug is being used, the drugs should be administered at least five minutes apart. The solution from one individual unit is to be used immediately after opening for administration to one or both eyes. Since sterility cannot be maintained after the individual unit is opened, the remaining contents should be discarded immediately after administration.

Key Clinical Trial Data

Clinical studies of 3 to 15 months duration compared the IOP-lowering effect of dorzolamide hydrochloride-timolol maleate ophthalmic solution twice daily to individually- and concomitantly-administered 0.5% timolol twice daily and 2.0% dorzolamide twice and three times daily. The IOP-lowering effect of dorzolamide hydrochloride-timolol maleate ophthalmic solution twice daily was greater (1-3 mmHg) than that of monotherapy with either 2.0% dorzolamide three times daily or 0.5% timolol twice daily. The IOP-lowering effect of dorzolamide hydrochloride-timolol maleate ophthalmic solution twice daily was approximately 1 mmHg less than that of concomitant therapy with 2.0% dorzolamide three times daily and 0.5% timolol twice daily. Open-label extensions of two studies were conducted for up to 12 months, during which the IOP-lowering effect was consistent. In an active-treatment controlled, parallel, double-masked study in 261 patients with elevated intraocular pressure ≥ 22 mmHg, dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) had an IOP-lowering effect equivalent to that of dorzolamide hydrochloride-timolol maleate ophthalmic solution.

Warnings & Contraindications

Dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) is contraindicated in patients with: bronchial asthma or a history of bronchial asthma, severe chronic obstructive pulmonary disease; sinus bradycardia, second or third degree atrioventricular block, overt cardiac failure, cardiogenic shock; hypersensitivity to any component of this product.

Place in Therapy

Not reported in label.

Study Details

Study typeFda approval

PublishedFeb 2012

View Original Abstract ↓

1 INDICATIONS AND USAGE Dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) 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 of dorzolamide hydrochloride-timolol maleate ophthalmic solution administered twice a day was slightly less than that seen with the concomitant administration of 0.5% timolol administered twice a day and 2% dorzolamide administered three times a day [see Clinical Studies (14.1) ] . • Dorzolamide hydrochloride-timolol maleate ophthalmic solution (preservative-free) is a carbonic anhydrase inhibitor with a beta-adrenergic receptor blocking agent 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. • The IOP-lowering of dorzolamide hydrochloride-timolol maleate ophthalmic solution twice daily was slightly less than that seen with the concomitant administration of 0.5% timolol twice daily, and 2% dorzolamide three times daily. (1)