CLINICAL TRIALS PROFILE FOR ZARONTIN

All Clinical Trials for ZARONTIN

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00088452 ↗	Childhood Absence Epilepsy Rx PK-PD-Pharmacogenetics Study	Completed	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 3	2004-07-01	The purpose of this study is to determine the best initial treatment for childhood absence epilepsy.
NCT00088452 ↗	Childhood Absence Epilepsy Rx PK-PD-Pharmacogenetics Study	Completed	Children's Hospital Medical Center, Cincinnati	Phase 3	2004-07-01	The purpose of this study is to determine the best initial treatment for childhood absence epilepsy.
NCT00689585 ↗	Safety and Efficacy Study of Ethosuximide for the Treatment of Complex Regional Pain Syndrome (CRPS)	Terminated	McGill University	Phase 2	2008-09-01	Pain remains the most debilitating symptom for adult patients suffering from complex regional pain syndrome (CRPS). Most CRPS patients gain little to no relief from current painkillers. The purpose of this study is to evaluate the efficacy and safety of ethosuximide in search of much-needed adjunctive therapy to relieve the pain and suffering associated with CRPS.
NCT00689585 ↗	Safety and Efficacy Study of Ethosuximide for the Treatment of Complex Regional Pain Syndrome (CRPS)	Terminated	McGill University Health Center	Phase 2	2008-09-01	Pain remains the most debilitating symptom for adult patients suffering from complex regional pain syndrome (CRPS). Most CRPS patients gain little to no relief from current painkillers. The purpose of this study is to evaluate the efficacy and safety of ethosuximide in search of much-needed adjunctive therapy to relieve the pain and suffering associated with CRPS.
NCT00689585 ↗	Safety and Efficacy Study of Ethosuximide for the Treatment of Complex Regional Pain Syndrome (CRPS)	Terminated	McGill University Health Centre/Research Institute of the McGill University Health Centre	Phase 2	2008-09-01	Pain remains the most debilitating symptom for adult patients suffering from complex regional pain syndrome (CRPS). Most CRPS patients gain little to no relief from current painkillers. The purpose of this study is to evaluate the efficacy and safety of ethosuximide in search of much-needed adjunctive therapy to relieve the pain and suffering associated with CRPS.
NCT01122381 ↗	Comparison of a Drug and Placebo in the Prevention of Migraine Headaches	Terminated	Thomas Jefferson University	Phase 1/Phase 2	2011-12-01	The purpose of this study is to determine whether ethosuximide works better than placebo in the prevention of episodic migraine among veterans.

Clinical Trial Conditions for ZARONTIN

Condition Name

Condition Name for ZARONTIN
Intervention	Trials
Neuropathic Pain Diagnostic Questionnaire (DN4) ≥ 4	1
Neuropathic Traumatic Pain	1
Pain NRS ≥ 4	1
Peripheral Neuropathic Pain	1

Condition MeSH

Condition MeSH for ZARONTIN
Intervention	Trials
Epilepsy, Absence	1
Headache	1
Epilepsy	1
Syndrome	1

Clinical Trial Locations for ZARONTIN

Trials by Country

Trials by Country for ZARONTIN
Location	Trials
United States	23
China	1
France	1
Canada	1

Trials by US State

Trials by US State for ZARONTIN
Location	Trials
Pennsylvania	2
Connecticut	1
Colorado	1
California	1
Arkansas	1

Clinical Trial Progress for ZARONTIN

Clinical Trial Phase

Clinical Trial Phase for ZARONTIN
Clinical Trial Phase	Trials
Phase 3	1
Phase 2	2
Phase 1/Phase 2	1

Clinical Trial Status

Clinical Trial Status for ZARONTIN
Clinical Trial Phase	Trials
Completed	2
Terminated	2
Unknown status	1

Clinical Trial Sponsors for ZARONTIN

Sponsor Name

Sponsor Name for ZARONTIN
Sponsor	Trials
Fondation Apicil	1
University Hospital, Clermont-Ferrand	1
National Institute of Neurological Disorders and Stroke (NINDS)	1

Sponsor Type

Sponsor Type for ZARONTIN
Sponsor	Trials
Other	9
U.S. Fed	2
NIH	1

ZARONTIN Market Analysis and Financial Projection

Last updated: February 4, 2026

What Is the Current State of ZARONTIN's Clinical Trials?

ZARONTIN (ethosuximide) remains primarily approved for treating absence seizures, with limited recent clinical trial activity. The FDA granted orphan drug designation for a rare pediatric epilepsy subset in 2011, but no new pivotal clinical trials targeting expanded indications appear under active registration or recruiting status since 2015. Most research focus involves post-marketing studies and pharmacokinetic assessments rather than new efficacy trials.

Recent publications show minimal data on novel indications or formulation trials. No ongoing Phase I-III studies are registered on ClinicalTrials.gov as of Q1 2023. The absence of recent high-profile trials indicates limited near-term development activity.

How Is the Market for ZARONTIN Positioned?

Current Market Size

The U.S. epilepsy drug market was valued at approximately $1.2 billion in 2022, with ZARONTIN holding a small niche share due to its age and limited indications. Its sales are concentrated among Medicaid and specialty pharmacies serving pediatric epilepsy patients.

Competitors and Alternatives

ZARONTIN faces competition from newer anti-epileptic drugs (AEDs) with broader indications. Top competitors include:

• Valproate (depicts broader use but with safety concerns)
• Ethosuximide derivatives in development, aiming for better tolerability
• Levetiracetam and lamotrigine, which have expanded seizure treatment indications

Market penetration has diminished since the 1990s but remains stable in niche pediatric segments.

Market Dynamics

• Pricing: ZARONTIN is priced higher per treatment course than generics of newer AEDs.
• Prescriber Behavior: Many neurologists prefer newer AEDs with favorable safety profiles.
• Regulatory Trends: No recent approvals suggest limited pipeline activity, affecting future growth prospects.

What Are Market Projections for ZARONTIN?

Short-Term Outlook (Next 2 Years)

Sales likely remain stable within niche markets, with minimal growth expected. Off-label usage could sustain demand among specific patient subsets, but no significant market expansion is anticipated without new approvals.

Medium to Long-Term Outlook (3-10 Years)

• Limited pipeline activity suggests slow or no growth.
• Potential for off-label use in rare pediatric epilepsy could maintain some demand.
• If a new formulation or novel indication gains approval, market potential could expand modestly.

External Factors Impacting Market Growth

• Increasing adoption of newer AEDs with better tolerability.
• Patent expiration or generic competition for ethosuximide.
• Regulatory policies favoring newer, safer compounds over older agents.

What Are the Key Barriers and Opportunities?

Barriers

• Lack of recent clinical trials limits product innovation.
• Competition from newer agents reduces market share.
• Safety concerns related to ethosuximide's side effect profile.

Opportunities

• Repurposing for rare epilepsy syndromes via clinical trials.
• Development of modified formulations with improved tolerability.
• Advocacy for expanded pediatric orphan indications.

Summary of Market Assessment

ZARONTIN remains a niche treatment for absence seizures in pediatric populations. The clinical landscape shows limited development activity, and the market is dominated by newer AEDs offering broader efficacy and safety. Without significant pipeline advancements or regulatory changes, ZARONTIN's market is expected to decline gradually or plateau. Strategic opportunities exist in leveraging its orphan drug status for rare indications, provided clinical research resumes.

Key Takeaways

• No recent pivotal clinical trials for ZARONTIN since 2015.
• The drug's market share is declining due to competition and safety profiles.
• The global epilepsy drug market is expanding, but ZARONTIN faces limited growth pathways.
• Future prospects depend on clinical development, rare disease positioning, and regulatory strategies.
• Market stability hinges on niche pediatric use; mainstream expansion unlikely.

Frequently Asked Questions

1. Are there any ongoing clinical trials for ZARONTIN?
No registered ongoing Phase I-III trials for ZARONTIN as of 2023.

2. What are competing treatments to ZARONTIN?
Main competitors include newer AEDs like levetiracetam, lamotrigine, and valproate.

3. Is there potential for ZARONTIN in markets outside the U.S.?
Limited data and registration suggest minimal international expansion unless new trials or indications emerge.

4. How does ZARONTIN's safety profile compare with newer AEDs?
Ethosuximide is associated with gastrointestinal side effects and rare blood dyscrasias, which may be less favorable than newer AEDs with improved tolerability.

5. What strategic steps could revive ZARONTIN's market presence?
Conducting new trials for rare epilepsy indications, developing formulations with fewer side effects, and leveraging orphan drug designations.

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Citations:

1. Market data sourced from Grand View Research, 2022.
2. Clinical trial information obtained from ClinicalTrials.gov, accessed 2023.
3. Regulatory status based on FDA archives.
4. Competitor analysis from EvaluatePharma, Q1 2023.
5. Safety profile references from published medical literature.