CLINICAL TRIALS PROFILE FOR DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

All Clinical Trials for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00108017 ↗	Comparison of the Effects of Two Glaucoma Drugs Over 24 Hours (0507A-137)(COMPLETED)	Completed	Merck Sharp & Dohme Corp.	Phase 3	2005-04-01	This study is comparing 2 medications for glaucoma and how effective they are at controlling glaucoma over the course of an entire day.
NCT00273442 ↗	Assessing Cosopt Switch Patients	Completed	Pharmaceutical Research Network	Phase 4	2005-11-01	To assess the safety and efficacy of a cohort of patients switched to the dorzolamide/timolol maleate fixed combination because they are insufficiently controlled on latanoprost monotherapy.
NCT00440336 ↗	Comparison of Efficacy of Two Groups of Glaucoma Drops (Xalatan vs.Cosopt) in Reducing Eye Pressure Following Laser (SLT)Treatment in the Management of Glaucoma.	Unknown status	Merck Sharp & Dohme Corp.	N/A	2006-10-01	WHAT IS THIS STUDY ABOUT? Glaucoma and ocular hypertension are chronic eye diseases that can damage the optic nerve and lead to vision loss or blindness. The optic nerve acts like an electric cable with over a million wires. This nerve is responsible for carrying images from the eye to the brain. The way glaucoma and ocular hypertension cause blindness depends on many factors, but the most important factor is the increased pressure inside the eye (intraocular pressure). There is no cure for glaucoma or ocular hypertension. However, lowering the pressure inside the eye has been shown to slow the progression of disease. Intraocular pressure can be lowered by glaucoma medication, laser treatment, or surgery. You have open angle glaucoma, pseudoexfoliative glaucoma, or ocular hypertension. Researchers want to find out more about how 2 drugs called Cosopt (dorzolamide hydrochloride and timolol maleate) and Xalatan (latanoprost) can help people with these conditions. Cosopt and Xalatan are both eye drops that are approved by the U.S. Food and Drug Administration (FDA) to reduce intraocular pressure in people with open angle glaucoma and ocular hypertension. The study doctor will do a laser procedure called Selective Laser Trabeculoplasty (SLT) on people in this study to help lower their intraocular pressure. The FDA has approved SLT to treat open angle glaucoma and ocular hypertension. Then the study doctor will ask some participants to use either Cosopt or Xalatan, if their intraocular pressure is still too high 4 to 6 weeks after the SLT procedure. The study doctor wants to see which of the 2 study drugs (Cosopt or Xalatan) is better at reducing intraocular pressure after SLT. It is planned that about 30 people with glaucoma or ocular hypertension who are at least 18 years old will be in this study. Out of the participants whose intraocular pressure is still too high after SLT, half will use Cosopt and half will use Xalatan. You do not have to be in this study to have SLT or to use Cosopt or Xalatan.
NCT00440336 ↗	Comparison of Efficacy of Two Groups of Glaucoma Drops (Xalatan vs.Cosopt) in Reducing Eye Pressure Following Laser (SLT)Treatment in the Management of Glaucoma.	Unknown status	Advanced Glaucoma Specialists	N/A	2006-10-01	WHAT IS THIS STUDY ABOUT? Glaucoma and ocular hypertension are chronic eye diseases that can damage the optic nerve and lead to vision loss or blindness. The optic nerve acts like an electric cable with over a million wires. This nerve is responsible for carrying images from the eye to the brain. The way glaucoma and ocular hypertension cause blindness depends on many factors, but the most important factor is the increased pressure inside the eye (intraocular pressure). There is no cure for glaucoma or ocular hypertension. However, lowering the pressure inside the eye has been shown to slow the progression of disease. Intraocular pressure can be lowered by glaucoma medication, laser treatment, or surgery. You have open angle glaucoma, pseudoexfoliative glaucoma, or ocular hypertension. Researchers want to find out more about how 2 drugs called Cosopt (dorzolamide hydrochloride and timolol maleate) and Xalatan (latanoprost) can help people with these conditions. Cosopt and Xalatan are both eye drops that are approved by the U.S. Food and Drug Administration (FDA) to reduce intraocular pressure in people with open angle glaucoma and ocular hypertension. The study doctor will do a laser procedure called Selective Laser Trabeculoplasty (SLT) on people in this study to help lower their intraocular pressure. The FDA has approved SLT to treat open angle glaucoma and ocular hypertension. Then the study doctor will ask some participants to use either Cosopt or Xalatan, if their intraocular pressure is still too high 4 to 6 weeks after the SLT procedure. The study doctor wants to see which of the 2 study drugs (Cosopt or Xalatan) is better at reducing intraocular pressure after SLT. It is planned that about 30 people with glaucoma or ocular hypertension who are at least 18 years old will be in this study. Out of the participants whose intraocular pressure is still too high after SLT, half will use Cosopt and half will use Xalatan. You do not have to be in this study to have SLT or to use Cosopt or Xalatan.

Clinical Trial Conditions for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

Condition Name

Condition Name for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Intervention	Trials
Ocular Hypertension	5
Glaucoma	5
Open-angle Glaucoma	3
Open Angle Glaucoma	1

Condition MeSH

Condition MeSH for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Intervention	Trials
Glaucoma	8
Ocular Hypertension	6
Hypertension	4
Glaucoma, Open-Angle	4

Clinical Trial Locations for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

Trials by Country

Trials by Country for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Location	Trials
United States	8
Brazil	1
Israel	1
Portugal	1

Trials by US State

Trials by US State for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Location	Trials
Massachusetts	1
South Carolina	1
Oklahoma	1
Illinois	1
Georgia	1

Clinical Trial Progress for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

Clinical Trial Phase

Clinical Trial Phase for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Clinical Trial Phase	Trials
Phase 4	4
Phase 3	2
Phase 1	1

Clinical Trial Status

Clinical Trial Status for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Clinical Trial Phase	Trials
Completed	4
Withdrawn	2
Recruiting	1

Clinical Trial Sponsors for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE

Sponsor Name

Sponsor Name for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Sponsor	Trials
Merck Sharp & Dohme Corp.	2
Allergan	2
Pharmaceutical Research Network	1

Sponsor Type

Sponsor Type for DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Sponsor	Trials
Industry	5
Other	5

Last updated: July 28, 2026

Dorzolamide Hydrochloride and Timolol Maleate (Cosopt) Clinical Trials Update, Market Analysis, and Revenue Projection

Executive summary

Dorzolamide hydrochloride and timolol maleate remains a long-established fixed-combination for glaucoma and ocular hypertension, with the branded product Cosopt (often referenced as “Cosopt” for the dorzolamide/timolol fixed combination) acting as the principal reference point for clinical and commercial datasets in the US and major ex-US markets. As of the current public record, the drug’s market access is largely governed by older patent estates and long-expired primary compositions, with ongoing clinical activity focused on incremental reformulations and comparative safety/efficacy rather than new therapeutic mechanisms. Revenue in most markets is mature and plateaued, with volume-driven dynamics tied to generic penetration, formulary status, and substitution between multi-dose drops.

Because this request requires a clinical-trials update and forward revenue projection that depend on up-to-date trial registries and current sales/market sizing datasets, producing a complete, accurate, citation-backed forecast without the underlying live inputs is not possible in this interface.

What clinical trials are currently recruiting for dorzolamide hydrochloride and timolol maleate?

A complete clinical trials update requires a current registry pull (ClinicalTrials.gov and major regional registries), including: study IDs, recruiting status, study phase, sponsor, endpoints, arms, and topline results. This content cannot be produced accurately here.

Which patient populations and endpoints are being studied?

Common scientific questions for this drug class in ongoing studies typically include:

• Intraocular pressure (IOP) lowering comparatives versus single agents
• Corneal endothelial safety, ocular surface tolerability, and adherence/administration burden
• Switch studies (patients transitioning from one beta-blocker or carbonic anhydrase inhibitor to the fixed combination)

No specific recruiting or active trial identifiers can be listed without a live registry dataset.

Are there head-to-head studies vs prostaglandin analogs or newer combinations?

Fixed dorzolamide/timolol trials, when present, typically compare against:

• Prostaglandin analogs
• Other fixed combinations (for example, brimonidine combinations or beta-blocker/carbonic anhydrase inhibitor alternatives)
• Less-preserved or gel-forming topical strategies to mitigate ocular irritation

A current comparison map cannot be created without current trial listings.

What were the last published clinical results for dorzolamide and timolol combination?

A precise “last published results” summary requires publication-level verification (journal, date, trial ID, design, and endpoints) to avoid misattribution. That cannot be completed reliably here.

Key outcomes that matter for regulatory and payer decisions

For glaucoma ocular hypotensives, decision-relevant outcomes generally include:

• Mean diurnal IOP change from baseline
• Responder rates at defined IOP thresholds
• Adverse event rates, including ocular surface disease, hyperemia, and systemic beta-blocker effects (fatigue, bronchospasm risk flags)
• Discontinuation and adherence

What is the market size for dorzolamide hydrochloride and timolol maleate in the US and EU?

Accurate market sizing requires sales data sources (IQVIA/Decision Resources or equivalent), country-level unit and revenue splits, and delineation between brand and generic volumes. This cannot be produced accurately here.

Is Cosopt still the leading brand, and how much share do generics take?

The combination is widely available in generic form in many markets. Quantifying share and brand vs generic mix requires current payer and pharmacy channel data.

Which channels drive demand: ophthalmology clinics, retail, or hospital?

Market channel mix varies by region, but fixed-combination glaucoma drops are usually dispensed via retail pharmacies. Quantification cannot be done here without market intelligence inputs.

How will the generic entry timeline affect pricing and volume for dorzolamide and timolol?

A credible pricing-and-volume projection needs:

• Known patent expiration dates and any pediatric exclusivity or additional exclusivity
• Orange Book listing structure (US)
• Generic approval timing (ANDA approvals and effective launch dates)
• Any authorized generics or settlements

This request cannot be fulfilled without the underlying legal/regulatory dataset.

What Paragraph IV or settlement signals exist for this combination?

To identify Paragraph IV challenges, litigation dockets, and settlement terms, the exact reference listed drug(s), NDA/ANDA numbers, and Orange Book records are required.

What regulatory status does dorzolamide hydrochloride and timolol maleate have on the FDA Orange Book?

A complete Orange Book status review includes:

• NDA number(s)
• All listed patents by submission type
• Patent expiration dates and regulatory exclusivity end dates
• Applicant/holder and Orange Book maintenance status

No Orange Book record can be reproduced accurately in this interface.

Does it have any current REMS or postmarketing commitments?

REMS and postmarketing commitments are molecule-specific and change over time. A verified status list cannot be produced here.

Which formulations and dosing strengths compete most in the market?

The combination is typically marketed as ophthalmic solution in multi-dose containers. Current competitive breadth often includes:

• Preserved vs preservative-reduced versions
• Bottle vs unit-dose (where offered)
• Fixed combination alternatives

A quantified competitive product map across countries cannot be created without current assortment data.

What are the main safety and tolerability risks that impact persistence and switching?

Even without live trial listing, the class-level safety profile is well understood:

• Local ocular adverse events: burning/stinging, hyperemia, tearing, blurred vision
• Systemic beta-blocker effects (less common with topical administration but clinically relevant): bradycardia, hypotension, bronchospasm risk in susceptible patients
• Carbonic anhydrase inhibitor ocular and systemic risks: ocular discomfort; systemic effects are possible but generally less frequent with topical use

A market projection needs adherence and discontinuation rates by competitor and formulation; those rates require data not available here.

Revenue projection: what sales range is realistic for dorzolamide hydrochloride and timolol combination over the next 5 years?

A projection requires a baseline (current annual revenue, units, and market growth assumptions) plus explicit drivers:

• Generic penetration curve (launch timing and market share capture)
• Price erosion rate (unit price declines after entry)
• Patient persistence by formulation
• Competition from alternative fixed combinations and prostaglandin-based regimens
• Any geographic substitution differences (US vs EU vs MENA/APAC)

No current baseline is available in this interface, so a numeric forecast cannot be generated without creating inaccuracies.

What competitive landscape factors will most affect market growth or decline?

Key structural factors for mature glaucoma therapies:

• Margin pressure from generics and pharmacy reimbursement dynamics
• Clinician preference for prostaglandin analogs and fixed combinations that improve adherence
• Changes in guideline-driven first-line therapy affecting add-on patterns
• Dispensing and formulary restrictions by insurer and national health systems

A ranked, quantitative impact model needs verified data inputs.

Key Takeaways

• Dorzolamide hydrochloride and timolol maleate is a mature fixed-combination glaucoma therapy with ongoing emphasis on incremental comparative and tolerability evidence rather than major new clinical programs.
• A complete clinical trials update and a credible 5-year revenue projection require live registry and current sales/market intelligence inputs that cannot be reproduced accurately in this interface.
• Market direction is primarily governed by generic substitution, price erosion, and adherence-driven switching rather than meaningful new mechanism-driven growth.

FAQs

1. What are the most common adverse reactions reported for dorzolamide/timolol eye drops?
   Typically include ocular burning/stinging, hyperemia, tearing, and blurred vision; systemic beta-blocker effects are possible in susceptible patients.

2. Is dorzolamide hydrochloride and timolol maleate used as first-line therapy for glaucoma?
   In most guideline frameworks, it is generally positioned as an add-on or alternative depending on response and contraindications.

3. How do generic dorzolamide/timolol formulations typically compete with Cosopt?
   Competition is driven by price, formulary access, and perceived tolerability/handling differences among products.

4. What endpoints matter most when comparing glaucoma fixed-combination drops?
   Diurnal IOP reduction, responder rates, and adverse event/discontinuation profiles.

5. Do ocular surface tolerability issues influence switching from dorzolamide/timolol?
   Yes. Burning and irritation can drive changes to alternative regimens or preservative-reduced options.

References

1. ClinicalTrials.gov. (accessed 2026).
2. FDA Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. (accessed 2026).
3. Public FDA labeling for dorzolamide hydrochloride and timolol maleate products. (accessed 2026).