CLINICAL TRIALS PROFILE FOR TOPIRAMATE

All Clinical Trials for topiramate

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001725 ↗	Studies of Dextromethorphan and Topiramate to Treat Oral and Facial Pain	Completed	National Institute of Dental and Craniofacial Research (NIDCR)	Phase 2	1997-12-01	This study will evaluate the safety and effectiveness of two drugs-dextromethorphan and topiramate-in treating orofacial (mouth and face) pain. Dextromethorphan, a commonly used cough suppressant, and topiramate, an anti-seizure medicine, block certain receptors on brain and spinal nerve cells that may cause the cells to produce electrical discharges and pain. Patients 18 years of age and older with oral and facial pain with trigeminal nerve damage and who have had pain daily for at least 3 months may be eligible for this study. Candidates will be screened with a medical history, physical examination, blood tests and psychiatric evaluation. These results will serve as baseline values for participants. Those enrolled in the study will take either dextromethorphan or topiramate in a 2-part study as follows: Dextromethorphan In Part 1, patients will take dextromethorphan and lorazepam (a commonly used anti-anxiety drug) separately in two 6-week periods. (Lorazepam is used in this study as an "active placebo" for comparison with dextromethorphan. An active placebo is a drug that does not work for the problem being studied but whose side effects are like those of the test drug.) They will take dextromethorphan for 4 weeks to determine the maximum tolerated dose (the highest dose that does not cause troubling side effects) and will stay on that dose for the remaining 2 weeks. Then they will repeat this process with lorazepam. Patients who respond to either drug may continue with Part 2 of the study, which compares these two drugs four more times to confirm the response seen in Part 1. In Part 2, the maximum tolerated dose will be determined in a 2-week period and that dose will be continued for another 2 weeks. This procedure will be repeated eight times. Throughout the study, patients will keep a daily pain diary. They will be contacted by telephone 2 to 3 times a week during dose escalation to check for side effects. At the end of each of the two 6-week periods in Part 1 and at the end of each 4-week period in Part 2 of the study, patients will have a 1-hour clinic visit. Participants who live more than a few hours' drive from NIH will have a full telephone follow-up evaluation instead of the clinic visits. Topiramate Patients who receive topiramate will follow a plan similar to that described above for dextromethorphan, with the following exceptions. They will take topiramate and an inactive placebo (a look-alike pill that has no active ingredients) in two separate 12-week periods. Patients' maximum tolerated dose will be determined in the first 8 weeks and they will stay on that dose for the remaining 4 weeks of each period. Patients who respond to the medication in Part 1 may continue with Part 2 to confirm the response. Part 2 consists of six 6-week periods. The first 4 weeks of each will be used to determine the maximum tolerated dose and the patient will remain on that dose for the next 2 weeks. Patients will keep a daily pain diary and will be contacted by phone 2 to 3 times a week while doses are being increased. Patients who complete Part 2 of the topiramate study may participate in another phase of the study that will last for 2 years. Those who continue for this phase will take topiramate for the 2-year period. They will be followed regularly by a study nurse and will come to NIH every 6 months for a follow-up visit.
NCT00004776 ↗	Phase III Randomized, Double-Blind, Placebo-Controlled Study of Oral Topiramate for Lennox-Gastaut Syndrome	Completed	University of California, Los Angeles	Phase 3	1993-11-01	OBJECTIVES: I. Evaluate the safety and efficacy of oral topiramate in patients with Lennox-Gastaut syndrome.
NCT00004776 ↗	Phase III Randomized, Double-Blind, Placebo-Controlled Study of Oral Topiramate for Lennox-Gastaut Syndrome	Completed	National Center for Research Resources (NCRR)	Phase 3	1993-11-01	OBJECTIVES: I. Evaluate the safety and efficacy of oral topiramate in patients with Lennox-Gastaut syndrome.
NCT00004807 ↗	Study of the Pathogenesis of Rett Syndrome	Completed	Johns Hopkins University	N/A	1995-01-01	OBJECTIVES: I. Extend current knowledge of the phenotype and natural history of Rett syndrome (RS). II. Continue the search for a cytogenetic and/or DNA marker. III. Study the effects of cholinergic drugs based on preliminary evidence for reduced levels of brain acetylcholine, while continuing supportive care to modify seizures, respiratory abnormalities, and motor disturbances, and improve nutrition, behavior, and learning. IV. Identify targets for future therapeutic interventions, e.g., growth factors, to influence neurologic recovery.
NCT00004807 ↗	Study of the Pathogenesis of Rett Syndrome	Completed	Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)	N/A	1995-01-01	OBJECTIVES: I. Extend current knowledge of the phenotype and natural history of Rett syndrome (RS). II. Continue the search for a cytogenetic and/or DNA marker. III. Study the effects of cholinergic drugs based on preliminary evidence for reduced levels of brain acetylcholine, while continuing supportive care to modify seizures, respiratory abnormalities, and motor disturbances, and improve nutrition, behavior, and learning. IV. Identify targets for future therapeutic interventions, e.g., growth factors, to influence neurologic recovery.
NCT00006205 ↗	Alcohol Dependency Study: Combining Medication Treatment for Alcoholism	Unknown status	National Institute on Alcohol Abuse and Alcoholism (NIAAA)	Phase 2	2005-03-01	The purpose of this study is to learn whether ondansetron and topiramate either alone or in combination is safe and effective in the treatment of alcohol dependence. This 13 week out-patient clinical trial is randomized, double-blind, and placebo-controlled. There are post-study follow up visits 1, 2 and 3 months after the end of the study. Participants will receive ondansetron and topiramate either alone or in combination or a placebo coupled with psychotherapy.
NCT00006205 ↗	Alcohol Dependency Study: Combining Medication Treatment for Alcoholism	Unknown status	Bankole Johnson	Phase 2	2005-03-01	The purpose of this study is to learn whether ondansetron and topiramate either alone or in combination is safe and effective in the treatment of alcohol dependence. This 13 week out-patient clinical trial is randomized, double-blind, and placebo-controlled. There are post-study follow up visits 1, 2 and 3 months after the end of the study. Participants will receive ondansetron and topiramate either alone or in combination or a placebo coupled with psychotherapy.

Clinical Trial Conditions for topiramate

Condition Name

Condition Name for topiramate
Intervention	Trials
Migraine	42
Epilepsy	38
Obesity	36
Seizures	20

Condition MeSH

Condition MeSH for topiramate
Intervention	Trials
Migraine Disorders	62
Epilepsy	45
Alcoholism	32
Disease	30

Clinical Trial Locations for topiramate

Trials by Country

Trials by Country for topiramate
Location	Trials
United States	326
Canada	24
Poland	10
Germany	9
France	8

Trials by US State

Trials by US State for topiramate
Location	Trials
California	33
Pennsylvania	20
Ohio	19
Virginia	19
Florida	16

Clinical Trial Progress for topiramate

Clinical Trial Phase

Clinical Trial Phase for topiramate
Clinical Trial Phase	Trials
PHASE4	8
PHASE3	4
PHASE2	1

Clinical Trial Status

Clinical Trial Status for topiramate
Clinical Trial Phase	Trials
Completed	188
Recruiting	34
Terminated	29

Clinical Trial Sponsors for topiramate

Sponsor Name

Sponsor Name for topiramate
Sponsor	Trials
Johnson & Johnson Pharmaceutical Research & Development, L.L.C.	52
Ortho-McNeil Neurologics, Inc.	21
National Institute on Alcohol Abuse and Alcoholism (NIAAA)	14

Sponsor Type

Sponsor Type for topiramate
Sponsor	Trials
Other	277
Industry	161
NIH	52

Last updated: April 27, 2026

Topiramate: Clinical Trials Update, Market Analysis, and Projections

What is the current clinical-trial posture for topiramate?

Topiramate is an established, off-patent small molecule used across multiple labeled indications, so the “clinical trials update” is dominated by (1) label expansions, (2) comparative/real-world effectiveness work, and (3) new formulations or trial designs rather than first-in-class development.

Trial landscape pattern

• Indication breadth: epilepsy (adult and pediatric subsets), migraine prophylaxis, and off-label neurologic and psychiatric use (trial activity persists, but off-label uptake does not always translate into new approvals).
• Evidence generation style: most recent activity is typically oriented to safety/tolerability under modern standards, endpoints aligned to new guideline language, and comparative effectiveness against other standards of care.
• Regulatory strategy: new drug substance patents are largely expired; sponsors focus on formulation, patient subgroups, combination regimens, or indication-specific claims.

Implication for investors and R&D

• Expect a higher share of trials tied to labeling refinements than to breakthrough efficacy.
• Prize-linked R&D efforts are usually positioned as product lifecycle management rather than a new molecular entity.

How big is the topiramate market today?

Topiramate is commercially mainstream due to:

• Broad clinician familiarity and guideline presence in neurologic care.
• Multiple commercial sources (generics across key markets).
• Persistent demand for long-term seizure control and migraine prevention.

Because topiramate is largely generic, market sizing typically shows up as:

• Aggregate branded and generic units in neurology/anticonvulsant segments.
• Revenue concentration in regions with different generic penetration and reimbursement structures.

Market structure

• Supply: high due to extensive generic competition.
• Pricing: pressure-driven, with “mix” effects from channel and reimbursement.
• Demand drivers: persistent chronic indications (epilepsy) and recurring preventative use (migraine prophylaxis).

Commercial takeaway

• The economic center of gravity is volume and reimbursement durability, not premium pricing.
• New entrants win through distribution, payer strategy, and lifecycle extensions, not differentiation by mechanism alone.

What market drivers keep demand stable or growing?

Topiramate demand is anchored by chronic treatment patterns and treatment guideline alignment.

Primary demand drivers

• Epilepsy maintenance: long-term use in a range of seizure types and patient ages.
• Migraine prevention: ongoing preventive prescribing, often in combination pathways.
• Generic accessibility: broad availability supports treatment continuity.

Secondary drivers

• Payer formulary positioning: generic status can enable stable coverage if managed-care policies favor cost.
• Real-world persistence: chronic neurologic drugs tend to show stable churn dynamics compared with episodic therapies.

Where does growth come from if molecule innovation is limited?

With limited patent runway for the base compound, growth typically comes from product and execution.

Growth levers

• Formulation lifecycle: extended-release or alternative dosing presentations (where commercially available) can lift adherence and payer pull-through.
• Geographic expansion of distribution: increasing generic market penetration in lower-access regions.
• Narrow-use re-targeting: trials that support stronger subgroup claims can improve formulary acceptance even without premium pricing.

What does the projection horizon look like?

A realistic projection for topiramate is not “molecule-driven expansion.” It is therapeutic maintenance plus market-share dynamics under generic competition.

Base-case projection logic (generic lifecycle)

• Volume: generally stable to modestly up, supported by chronic indication prevalence.
• Price: down or flat over time due to generic erosion, with episodic spikes tied to shortages, manufacturing shifts, or formulary renegotiations.
• Revenue: tracks volume with a downward bias unless mix improves via preferred products or formulation differentiation.

Practical projection outcomes

• Near term (12 to 24 months): revenue stability or gradual decline, with volatility driven by pricing and supply.
• Mid term (2 to 5 years): modest volume offset against price compression, yielding low single-digit revenue growth in optimistic scenarios or low single-digit declines in conservative scenarios.
• Long term (5+ years): market becomes structurally “mature,” with growth mostly tied to formulary wins and distribution expansion.

Clinical development and regulatory: what matters for future approvals?

For topiramate, future “clinical trials wins” tend to be defined less by new mechanism proof and more by:

• Patient selection that improves clinically meaningful endpoints.
• Endpoint modernization that matches regulatory expectations.
• Safety and tolerability in targeted populations (e.g., specific age groups, comorbidity patterns).

What tends to trigger meaningful regulatory outcomes

• New label language that aligns with guideline endpoints.
• Combination strategy data that supports an evidence-based placement in treatment algorithms.
• Formulation improvements that produce adherence benefits without sacrificing safety.

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Key Takeaways

1. Topiramate is mature and largely generic, so the “clinical trials update” is mostly label refinements, subgroup work, and product lifecycle studies rather than molecular breakthroughs.
2. The market is structurally stable because demand is chronic (epilepsy) and preventive (migraine), but revenue faces persistent price pressure from generic competition.
3. Projections align with a mature-market profile: stable or modestly growing volumes with revenue constrained by ongoing pricing compression, unless mix improves via formulation or formulary preference.
4. The highest ROI development paths are formulation and indication-specific evidence that strengthens payer and clinician adoption, not first-in-class mechanism repositioning.

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FAQs

1) Is topiramate still being studied in clinical trials?

Yes. Trial activity continues, concentrated on indication refinement, subgroups, comparative effectiveness, and formulation or dosing approaches rather than new molecular entity development.

2) Does generic competition cap topiramate market growth?

It caps revenue growth more than it caps volume. Demand persists, but pricing is vulnerable to generic erosion and payer-driven cost benchmarks.

3) What are the main commercial drivers for topiramate?

Chronic epilepsy maintenance and migraine prophylaxis, supported by broad generic availability and payer formulary dynamics.

4) What types of trials are most likely to support regulatory or payer impact?

Trials with clinically meaningful endpoints in relevant subgroups, aligned to guideline language, and studies that strengthen the evidence position of a specific formulation or regimen.

5) What is the most realistic revenue projection direction?

A mature-market profile: stable to modestly down revenue near term, with low single-digit outcomes over mid term depending on pricing and product mix, unless a formulation or channel shift improves preference.

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References

[1] FDA. Topamax (topiramate) prescribing information. U.S. Food and Drug Administration.
[2] EMA. Topamax (topiramate) product information. European Medicines Agency.
[3] ClinicalTrials.gov. Search results for “topiramate” (accessed 2026-04-27). National Library of Medicine.
[4] WHO. ATC classification for topiramate (N03AX11). World Health Organization.