CLINICAL TRIALS PROFILE FOR DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE

All Clinical Trials for DORZOLAMIDE HYDROCHLORIDE; 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.
NCT00471068 ↗	Study of Travatan and Cosopt in Primary Open-Angle Glaucoma or Ocular Hypertension	Terminated	Alcon Research	Phase 4	2007-03-01	To compare the efficacy and safety in patients treated with travoprost versus dorzolamide/timolol maleate combination in patients with open-angle glaucoma or ocular hypertension

Clinical Trial Conditions for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE

Condition Name

Condition Name for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE
Intervention	Trials
Glaucoma	5
Ocular Hypertension	5
Open-angle Glaucoma	3
Exfoliation Syndrome	1

Condition MeSH

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

Clinical Trial Locations for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE

Trials by Country

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

Trials by US State

Trials by US State for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE
Location	Trials
Florida	1
Indiana	1
Massachusetts	1
South Carolina	1
Oklahoma	1

Clinical Trial Progress for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE

Clinical Trial Phase

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

Clinical Trial Status

Clinical Trial Status for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE
Clinical Trial Phase	Trials
Completed	4
Withdrawn	2
Unknown status	1

Clinical Trial Sponsors for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE

Sponsor Name

Sponsor Name for DORZOLAMIDE HYDROCHLORIDE; TIMOLOL MALEATE
Sponsor	Trials
Allergan	2
Merck Sharp & Dohme Corp.	2
Advanced Glaucoma Specialists	1

Sponsor Type

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

Clinical Trials Update, Market Analysis, and Projection: Dorzolamide Hydrochloride; Timolol Maleate

Last updated: April 25, 2026

What is the product and why does it matter commercially?

Dorzolamide hydrochloride; timolol maleate is a fixed-dose combination (FDC) ophthalmic therapy used to lower intraocular pressure (IOP) in patients with conditions such as open-angle glaucoma and ocular hypertension. It is a long-established, branded and generic class product in the glaucoma market.

Commercially, this is a high-volume, chronic-use therapy category with:

• Ongoing demand driven by aging demographics and chronic disease prevalence
• Price pressure driven by generic entry and multi-source competition
• Regulatory and formulation competition concentrated in the fields of preservative systems, drop comfort, adherence, and device formats (e.g., bottle systems and dosing regimens)

What do current clinical-trials signals show for this specific FDC?

Global clinical-trials activity (search pattern)

For an established FDC, trial activity typically shifts from pivotal efficacy trials to:

• Bioequivalence / pharmacokinetic studies (generic and reformulation programs)
• Formulation and tolerability studies (preservative changes, viscosity changes, bottle and delivery improvements)
• Comparative IOP lowering studies versus other standard-of-care regimens

Because dorzolamide/timolol is an older FDC, the most frequent “new” studies in public registries are generally:

• Small to medium enrollment
• Short duration
• IOP and safety endpoints
• Statistical designs oriented to non-inferiority or equivalence

Clinical-trials update (actionable interpretation)

• Expect continued new submissions, but mostly reformulation/bioequivalence rather than new clinical evidence that changes standard-of-care.
• Market impact is less about new efficacy differentiation and more about availability, pricing, and product switching (preservative tolerability and adherence).

What is the competitive market structure?

Who competes in dorzolamide/timolol?

Competition comes from two directions:

1) Same-class FDC ophthalmics

• Other fixed combinations of carbonic anhydrase inhibitors (CAIs) and beta-blockers
• Alternative FDCs that target IOP lowering through different complementary mechanisms

2) Monotherapy substitution

• Separate CAI (e.g., dorzolamide alone) plus separate beta-blocker (e.g., timolol alone)
• Other glaucoma drug classes that compete for formulary share (prostaglandin analogs, alpha agonists, etc.)

Competitive implications

• Formulary substitution risk increases when:
  • A payer prefers a different class on cost-effectiveness
  • A patient experiences ocular surface irritation or tolerability issues
  • Generic market share expands and compresses pricing for the FDC itself
• Switching friction is lower in ophthalmology than in many therapeutic areas because treatment is topical and adjustment happens in-office.

How big is the market and what drives volume?

Demand drivers

• Chronic treatment: patients maintain therapy for extended periods.
• Medication persistence varies by ocular tolerability and dosing convenience.
• IOP target achievement drives continued use and escalation to other therapies when needed.

Supply drivers

• Generic manufacturing scale supports stable supply.
• Regulatory and quality system maturity determines which suppliers can consistently meet demand.
• Preservative strategy can influence payer preference and physician prescribing.

Market projection: what is likely to happen to pricing, volume, and revenue?

Pricing trajectory (base case)

For an established generic-capable ophthalmic FDC:

• Net price tends to decline as multi-source competition expands
• Revenues grow slower than unit volumes if pricing falls faster than demand expands

Volume trajectory (base case)

• Unit growth tracks patient population growth and persistence, with incremental volume gains from:
  • Substitution away from single agents toward combination therapy for IOP control
  • Clinician preference for simplifying regimens (fewer bottles)

Revenue projection framework (directional)

Use a three-factor model common to mature ophthalmics:

1. Patient pool growth (slow, demographic-driven)
2. Share of combination therapy (depends on tolerability, formulary placement)
3. Price erosion (generic intensity and tender dynamics)

Base case expectation

• Units rise modestly
• Average selling price declines
• Market value growth stays low-to-moderate versus volume growth

What are the key “watch items” that can change the outlook?

1) Preservative and tolerability positioning

Topical glaucoma therapies compete heavily on ocular surface tolerability. Products with improved comfort profiles can gain share even in the presence of generics.

2) Bottle, dosing, and adherence programs

Adherence programs and device improvements influence persistence. Any changes that reduce perceived discomfort or complexity can increase continued use.

3) Payer formularies and step edits

Formulary placement is often decisive. If payers prefer certain classes or combinations, market share shifts rapidly.

Commercial-grade clinical endpoints: what matters for this class

For ongoing studies and post-approval lifecycle programs, decision-relevant endpoints usually center on:

• IOP reduction from baseline at specified timepoints
• Safety including ocular adverse events (burning, stinging, hyperemia) and systemic beta-blocker-related signals (where monitored)
• Tolerability and adherence-related measures

In practice, these do not generally create step-change clinical differentiation for the established FDC, but they do influence physician and payer acceptance.

Key Takeaways

• Dorzolamide hydrochloride; timolol maleate is a mature, fixed-dose ophthalmic IOP-lowering therapy facing persistent generic and class-level competition.
• Clinical-trials activity for this FDC is most likely to be reformulation, tolerability, and bioequivalence-oriented, rather than new efficacy-defining programs.
• Market outcomes are expected to follow a mature ophthalmics pattern: modest unit growth, price erosion, and low-to-mid single digit value growth (with variability by region and payer policy).
• The highest leverage drivers for share are tolerability/preservative strategy, formulary placement, and persistence/adherence dynamics rather than novel mechanism claims.

FAQs

1) Is dorzolamide/timolol expected to face major efficacy-disrupting competition soon?
Typically no. The competitive set is dominated by established classes and multi-source generics; differentiation tends to come from tolerability, dosing convenience, and formulary position rather than new primary efficacy.

2) What type of studies most frequently appear for this established FDC?
Most new public signals tend to be bioequivalence, pharmacokinetic, tolerability, or formulation-performance studies with IOP and safety endpoints.

3) What matters most for prescriber adoption in this segment?
Ocular comfort, preservative tolerability, dosing regimen simplicity, and alignment with payer formulary expectations.

4) How does generic entry typically affect the market value?
It usually compresses average selling price, so revenue growth tends to rely on units and persistence rather than price.

5) What are the biggest levers for market share?
Formulary placement, patient persistence, tolerability-related switching, and supplier ability to maintain consistent supply.

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References

[1] Global Drug Trials. ClinicalTrials.gov. https://clinicaltrials.gov/
[2] National Library of Medicine. Dorzolamide hydrochloride and timolol maleate ophthalmic information (general resource entries via drug label databases). https://dailymed.nlm.nih.gov/
[3] U.S. Food and Drug Administration. Drug Approval Reports and product labeling (Dorzolamide/timolol combination labeling context). https://www.accessdata.fda.gov/