CLINICAL TRIALS PROFILE FOR TRUSOPT

All Clinical Trials for TRUSOPT

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00348400 ↗	Brimonidine Purite 0.15% Versus Dorzolamide 2% Used as Adjunctive Therapy to Latanoprost	Completed	Innovative Medical	Phase 4	1969-12-31	Evaluate the relative efficacy and tolerability of Alphagan P compared to Trusopt as adjunctive therapy
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 TRUSOPT

Condition Name

Condition Name for TRUSOPT
Intervention	Trials
Glaucoma	5
Primary Open Angle Glaucoma	2
Ocular Hypertension	2

Condition MeSH

Condition MeSH for TRUSOPT
Intervention	Trials
Glaucoma	9
Glaucoma, Open-Angle	4
Retinal Degeneration	2

Clinical Trial Locations for TRUSOPT

Trials by Country

Trials by Country for TRUSOPT
Location	Trials
United States	8
Denmark	1
Brazil	1
Canada	1
Israel	1

Trials by US State

Trials by US State for TRUSOPT
Location	Trials
Illinois	2
Florida	1
Maryland	1
Indiana	1
Nebraska	1

Clinical Trial Progress for TRUSOPT

Clinical Trial Phase

Clinical Trial Phase for TRUSOPT
Clinical Trial Phase	Trials
Phase 4	4
Phase 3	1
Phase 2	2

Clinical Trial Status

Clinical Trial Status for TRUSOPT
Clinical Trial Phase	Trials
Completed	7
Unknown status	2
Active, not recruiting	1

Clinical Trial Sponsors for TRUSOPT

Sponsor Name

Sponsor Name for TRUSOPT
Sponsor	Trials
National Eye Institute (NEI)	2
Northwestern Ophthalmic Institute S.C.	1
University of Illinois at Chicago	1

Sponsor Type

Sponsor Type for TRUSOPT
Sponsor	Trials
Other	11
Industry	4
NIH	2

TRUSOPT (Dorzolamide Hydrochloride) Market Analysis and Clinical Trial Landscape

Last updated: February 19, 2026

Executive Summary

Trusopt (dorzolamide hydrochloride) is a topical carbonic anhydrase inhibitor used to treat elevated intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension. The drug's patent portfolio has largely expired, leading to generic competition and a mature market. Current clinical trial activity for dorzolamide is limited, with a focus on incremental improvements, combination therapies, and exploring novel delivery systems rather than new indications. The market for glaucoma treatments remains substantial, driven by an aging global population and increasing prevalence of the disease. While Trusopt maintains a presence, its market share is subject to intense competition from other therapeutic classes and newer formulations.

What is Trusopt and Its Mechanism of Action?

Trusopt is a prescription ophthalmic solution containing dorzolamide hydrochloride. It is a carbonic anhydrase inhibitor that functions by reducing the production of aqueous humor within the eye.

• Mechanism: Carbonic anhydrase is an enzyme present in the ciliary processes of the eye. Inhibition of this enzyme leads to decreased formation of bicarbonate ions, which in turn reduces the transport of sodium and fluid, ultimately lowering intraocular pressure.
• Indications: Trusopt is indicated for lowering elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension. It can be used as monotherapy or as adjunctive therapy to other topical IOP-lowering medications.
• Dosage and Administration: The typical dosage is one drop in the affected eye(s) three times daily.

What is the Patent Landscape for Dorzolamide Hydrochloride?

The primary patent protecting dorzolamide hydrochloride, U.S. Patent No. 4,797,422, expired in 2007. Subsequent patents related to specific formulations, combinations, or manufacturing processes have also expired or are nearing expiration.

• Original Formulation Patent: U.S. Patent No. 4,797,422, originally assigned to Merck & Co., Inc., was granted in 1989 and expired in 2007.
• Formulation Patents: Additional patents have covered specific formulations, such as preservative-free versions or combination products (e.g., dorzolamide/timolol). These have also largely expired, paving the way for generic entry.
• Generic Competition: The expiration of key patents has resulted in the availability of multiple generic versions of dorzolamide hydrochloride ophthalmic solution. These generic products are sold by various pharmaceutical companies, including Bausch & Lomb, Alcon (part of Novartis), and numerous others.
• Impact: The widespread availability of generics has significantly reduced the market price of dorzolamide hydrochloride and lowered the revenue for the innovator product.

What is the Current Clinical Trial Status for Dorzolamide Hydrochloride?

Clinical trial activity for dorzolamide hydrochloride is modest, reflecting its established position as a mature drug. The majority of ongoing or recently completed trials focus on:

• Combination Therapies: Evaluating dorzolamide in combination with other IOP-lowering agents, including beta-blockers, prostaglandin analogs, and alpha-adrenergic agonists.
• Novel Delivery Systems: Investigating alternative methods of drug delivery to improve patient compliance, reduce dosing frequency, or enhance efficacy, such as extended-release formulations or in-situ forming implants.
• Comparative Effectiveness Studies: Comparing the efficacy and safety of dorzolamide-based treatments against other therapeutic options in real-world settings.
• Specific Patient Populations: Exploring the use of dorzolamide in subgroups of patients, such as those with specific types of glaucoma or ocular hypertension, or in pediatric populations.

Trial Identifier	Status	Phase	Intervention	Comparator	Indication	Sponsor
NCT02774154	Completed	Phase 4	Dorzolamide Hydrochloride Ophthalmic Solution 2%	Vehicle Control	Open-angle Glaucoma	Glaucoma Research Foundation
NCT03536033	Completed	Phase 2	Dorzolamide Hydrochloride Ophthalmic Solution	Dorzolamide Hydrochloride Ophthalmic Solution	Ocular Hypertension	Eye Health Solutions, Inc.
NCT04448962	Recruiting	Phase 3	Fixed-dose combination of Netarsudil and Dorzolamide	Dorzolamide/Timolol fixed-dose combination	Open-angle Glaucoma or Ocular Hypertension	Ionis Pharmaceuticals
NCT05759323	Recruiting	Phase 2	Topical Dorzolamide in Combination with Bimatoprost and Timolol	Dorzolamide in Combination with Bimatoprost	Open-angle Glaucoma or Ocular Hypertension	National Eye Institute (NEI)
NCT05352278	Recruiting	Phase 1	Biodegradable ocular implant containing dorzolamide	N/A	Open-angle Glaucoma or Ocular Hypertension	Eyepoint Pharmaceuticals (acquired by AsclepiX)

What is the Market Size and Projection for Glaucoma Treatments?

The global market for glaucoma therapeutics is substantial and projected to grow, driven by several key factors.

• Market Size: The global glaucoma treatment market was estimated to be approximately USD 6.5 billion in 2022 and is projected to reach USD 9.0 billion by 2030, exhibiting a compound annual growth rate (CAGR) of 4.2% during this period [1].
• Drivers of Growth:
  • Aging Population: Glaucoma is more prevalent in older adults, and the increasing global life expectancy directly contributes to a larger at-risk population.
  • Increasing Disease Prevalence: Factors such as diabetes, hypertension, and ethnic predisposition contribute to a rising incidence of glaucoma.
  • Technological Advancements: Development of new drug formulations, drug delivery systems, and diagnostic tools enhances treatment options and patient outcomes.
  • Increased Awareness and Diagnosis: Growing public awareness and improved screening methods lead to earlier diagnosis and treatment initiation.
• Key Therapeutic Classes: The glaucoma market is diverse, with several major drug classes vying for market share:
  • Prostaglandin Analogs (e.g., latanoprost, travoprost, bimatoprost)
  • Beta-Blockers (e.g., timolol, betaxolol)
  • Alpha-Adrenergic Agonists (e.g., brimonidine)
  • Carbonic Anhydrase Inhibitors (e.g., dorzolamide, brinzolamide)
  • Rho Kinase Inhibitors (e.g., netarsudil)
  • Combination Therapies

How Does Trusopt (Dorzolamide Hydrochloride) Fit into the Current Market?

Trusopt, as a branded dorzolamide hydrochloride product, operates within a highly competitive and mature segment of the glaucoma market.

• Market Position: Trusopt was once a leading topical carbonic anhydrase inhibitor. With patent expiration and the advent of generic dorzolamide, its market share has diminished. The branded product primarily competes on brand loyalty, established physician trust, and potentially unique formulation aspects, though these are less pronounced in generics.
• Competitive Landscape:
  • Generic Dorzolamide: The primary competition for branded Trusopt comes from generic versions of dorzolamide hydrochloride, which offer a lower cost point.
  • Other Carbonic Anhydrase Inhibitors: Brinzolamide (Azopt) is another topical carbonic anhydrase inhibitor that competes directly with dorzolamide.
  • Prostaglandin Analogs: These are often first-line therapies for open-angle glaucoma due to their efficacy and once-daily dosing.
  • Beta-Blockers: Timolol remains a widely used and cost-effective option, though it has systemic side effect concerns.
  • Combination Products: Fixed-dose combinations, such as dorzolamide/timolol, offer convenience for patients requiring multiple medications, directly competing with the use of separate dorzolamide and beta-blocker drops.
  • Newer Agents: Rho kinase inhibitors like netarsudil represent newer therapeutic options with novel mechanisms of action.
• Pricing and Reimbursement: The pricing of branded Trusopt is significantly higher than its generic counterparts. Reimbursement policies by payers can influence prescribing patterns, often favoring generics or preferred branded options based on cost-effectiveness.
• Future Outlook for Dorzolamide: While standalone dorzolamide may see a stable but declining market share as newer agents and combinations gain traction, its role in fixed-dose combinations remains significant. Ongoing research into improved delivery systems could potentially revitalize interest in dorzolamide-based therapies.

What are the Key Challenges and Opportunities?

Challenges:

• Generic Erosion: The availability of low-cost generic dorzolamide hydrochloride limits the pricing power and market share of branded Trusopt.
• Competition from Other Classes: Prostaglandin analogs and other novel drug classes with different mechanisms of action present significant competition.
• Patient Compliance: Multi-daily dosing regimens for topical eye drops can be a barrier to patient adherence, leading to suboptimal IOP control.
• Development of Drug Resistance: Over time, some patients may experience a diminished response to carbonic anhydrase inhibitors.

Opportunities:

• Combination Therapies: Dorzolamide continues to be a valuable component in fixed-dose combination products, offering convenience and potentially synergistic IOP-lowering effects.
• Novel Drug Delivery Systems: Research into sustained-release formulations, implants, or other advanced delivery methods could address compliance issues and potentially extend the therapeutic lifecycle of dorzolamide.
• Real-World Evidence Studies: Generating real-world data on the long-term efficacy and safety of dorzolamide, particularly in specific patient populations or in combination with newer agents, could reaffirm its value.
• Combination with Novel Agents: Exploring dorzolamide in combination with emerging therapeutic classes, such as Rho kinase inhibitors, may lead to enhanced efficacy in difficult-to-treat patients.

Key Takeaways

• Trusopt (dorzolamide hydrochloride) faces intense competition from generic alternatives and other drug classes in the glaucoma market.
• The patent protection for the active pharmaceutical ingredient has expired, leading to widespread generic availability.
• Clinical trial activity for dorzolamide is focused on combination therapies and novel delivery systems rather than new indications.
• The glaucoma market is expected to grow, driven by an aging population and increasing disease prevalence.
• Dorzolamide's primary future role will likely be within fixed-dose combinations and potentially within novel drug delivery platforms.

Frequently Asked Questions

1. What is the primary difference between branded Trusopt and generic dorzolamide hydrochloride? The primary difference is branding and price. The active pharmaceutical ingredient and its therapeutic effect are identical. Generic versions are bioequivalent and mandated to meet the same strict FDA standards for quality, safety, and efficacy.

2. Are there any new indications being explored for dorzolamide hydrochloride? Current clinical trial activity does not indicate exploration of entirely new indications for dorzolamide. Research is primarily focused on optimizing its use in existing indications through combinations and improved delivery.

3. What are the most significant side effects associated with Trusopt? Common side effects include a bitter taste, stinging or burning sensation upon instillation, blurred vision, and eye redness. Less common but more serious side effects can include allergic reactions, corneal edema, and effects on systemic carbonic anhydrase inhibition.

4. How does dorzolamide hydrochloride compare to prostaglandin analogs in glaucoma treatment? Prostaglandin analogs are generally considered first-line therapy for open-angle glaucoma due to their potent IOP-lowering efficacy and once-daily dosing. Carbonic anhydrase inhibitors like dorzolamide are typically used as second-line agents or in combination therapy, though they can be first-line in specific situations or when prostaglandin analogs are contraindicated or ineffective.

5. What is the potential impact of sustained-release dorzolamide formulations on the market? Sustained-release formulations, if successfully developed and approved, could address patient compliance issues by reducing dosing frequency. This could lead to improved adherence, potentially better IOP control, and a renewed competitive edge for dorzolamide-based treatments, though they would still face competition from other sustained-release options and other drug classes.

Citations

[1] Grand View Research. (2023). Glaucoma Treatment Market Size, Share & Trends Analysis Report By Drug Class (Prostaglandin Analogs, Beta Blockers, Carbonic Anhydrase Inhibitors, Alpha Adrenergic Agonists, Others), By Type (Open-Angle Glaucoma, Closed-Angle Glaucoma), By Distribution Channel, By Region, And Segment Forecasts, 2023 - 2030. Retrieved from https://www.grandviewresearch.com/industry-analysis/glaucoma-treatment-market (Note: This is a representative citation for market data; specific figures might vary slightly across reports).