Investigational Drug Information for Talampanel

What is the drug development status for Talampanel?

Talampanel is an investigational drug.

There have been 11 clinical trials for Talampanel. The most recent clinical trial was a Phase 2 trial, which was initiated on January 1^st 2002.

The most common disease conditions in clinical trials are Sclerosis, Glioblastoma, and Motor Neuron Disease. The leading clinical trial sponsors are Teva Pharmaceutical Industries, Teva Branded Pharmaceutical Products R&D, Inc., and National Institute of Neurological Disorders and Stroke (NINDS).

Summary for Talampanel

US Patents	0
International Patents	0
US Patent Applications	2,117
WIPO Patent Applications	736
Japanese Patent Applications	117
Clinical Trial Progress	Phase 2 (2002-01-01)
Vendors	39

Recent Clinical Trials for Talampanel

Title	Sponsor	Phase
A Phase 1 Study to Investigate the Effects of Talampanel on the Heart Rhythm	Cetero Research, San Antonio	Phase 1
A Phase 1 Study to Investigate the Effects of Talampanel on the Heart Rhythm	Teva Branded Pharmaceutical Products R&D, Inc.	Phase 1
A Phase 1 Study to Investigate the Effects of Talampanel on the Heart Rhythm	Teva Pharmaceutical Industries	Phase 1

See all Talampanel clinical trials

Clinical Trial Summary for Talampanel

Top disease conditions for Talampanel

Top clinical trial sponsors for Talampanel

See all Talampanel clinical trials

US Patents for Talampanel

Drugname	Patent Number	Patent Title	Patent Assignee	Estimated Expiration

Talampanel Development Update, Patent Position, and Market Projection

Last updated: September 5, 2026

Talampanel is an abandoned investigational AMPA-receptor antagonist with no FDA approval, no Orange Book listing, no active commercial product, and no identifiable late-stage development program. Its principal clinical programs in epilepsy, amyotrophic lateral sclerosis (ALS), and glioblastoma did not produce a viable regulatory or commercial path. The near-term market projection is therefore zero for branded sales and negligible for generic competition. Any future value would depend on a new sponsor demonstrating efficacy in a narrowly defined neurological indication.

What is talampanel and how does it work?

Talampanel, also known as LY300164, is a noncompetitive antagonist of the AMPA subtype of ionotropic glutamate receptors. AMPA receptors mediate fast excitatory neurotransmission in the central nervous system. Excessive glutamatergic signaling has been implicated in seizures, motor-neuron injury, migraine, and glioblastoma biology.

The compound was developed as an orally administered small molecule. Its mechanism differs from that of approved antiseizure drugs such as levetiracetam, lacosamide, lamotrigine, and perampanel. Perampanel is also an AMPA-receptor antagonist, but it is a separate compound with its own development history, patent estate, FDA approval, and commercial franchise.

Talampanel was investigated primarily as:

• Adjunctive treatment for refractory partial-onset seizures
• A disease-modifying treatment for ALS
• An investigational treatment for glioblastoma
• A potential therapy for other neurological disorders involving glutamate signaling

No indication generated sufficient evidence for approval.

What is the current development status of talampanel?

Talampanel is not an active FDA development program. Public clinical records and published literature identify completed or terminated studies rather than an ongoing sponsor-led registration program.

Development area	Development status	Commercial assessment
Epilepsy	Investigated in clinical studies; no approval	Failed to establish a durable market position
ALS	Randomized clinical testing did not show meaningful disease-modifying benefit	Program not commercially viable
Glioblastoma	Investigated in combination with standard treatment	No regulatory approval
Migraine and other neurological uses	Exploratory or limited development	No established pathway
FDA status	Not approved	No U.S. product market
Orange Book status	No listed product	No Orange Book-based generic entry
Current sales	None identified	Revenue projection is zero absent redevelopment

The most important development event was the failure of talampanel in ALS. A randomized, placebo-controlled clinical trial evaluated whether the drug could slow disease progression. The results did not demonstrate a clinically meaningful treatment effect, weakening the broader rationale for AMPA-receptor blockade as a disease-modifying ALS strategy (Lai et al., 2009).

What happened in the talampanel epilepsy program?

Talampanel reached clinical testing as an adjunctive therapy for refractory partial seizures. Early studies indicated that AMPA-receptor antagonism could reduce seizure activity in some patients. The program did not advance to FDA approval, however.

The epilepsy market is highly competitive and has a high evidentiary threshold. A new adjunctive antiseizure medicine must show reproducible seizure reduction, acceptable cognitive and psychiatric tolerability, manageable drug-drug interactions, and a commercially differentiated dosing profile.

Talampanel faced several barriers:

1. Limited evidence of superiority over existing adjunctive treatments.
2. No approved-label status to support physician adoption.
3. Competition from established drugs with broad reimbursement coverage.
4. The need to characterize chronic neurological and psychiatric adverse events.
5. A development history that did not produce a clear registration package.

Talampanel’s epilepsy studies are clinically relevant because they established pharmacologic activity, but they did not establish a commercially defensible product.

What were the ALS trial results for talampanel?

The ALS program produced the clearest negative development signal. A multicenter randomized trial assessed talampanel in patients with ALS. The study did not show a significant improvement in disease progression or survival-related outcomes sufficient to support further development.

The result matters commercially because ALS is a high-unmet-need indication with concentrated specialist prescribing. A positive result could have supported accelerated regulatory engagement and orphan-drug economics. The negative result removed the principal basis for a high-value rescue or licensing transaction.

Talampanel has not become part of the standard ALS treatment framework. Current ALS treatment decisions center on approved or guideline-supported therapies, including riluzole, edaravone, and disease-specific genetic treatment where applicable. Talampanel is not an established substitute for these products.

Was talampanel studied in glioblastoma?

Yes. Talampanel was studied in glioblastoma because AMPA-receptor signaling may contribute to tumor-cell proliferation, invasion, and excitotoxic interactions within the tumor microenvironment.

The investigational strategy combined talampanel with conventional glioblastoma treatment, including radiotherapy and temozolomide in some protocols. The program remained investigational and did not lead to approval.

Glioblastoma development is commercially difficult. Trial failure can result from inadequate penetration into tumor tissue, disease heterogeneity, rapidly changing standards of care, and difficulty separating drug activity from the effects of radiation and temozolomide. Talampanel did not establish a validated biomarker-defined patient population or a registrational efficacy profile.

What is the FDA regulatory status of talampanel?

Talampanel has no FDA approval and no approved prescription product. It therefore has:

• No New Drug Application approval
• No FDA-approved indication
• No U.S. prescribing information
• No FDA-recognized commercial exclusivity period
• No pediatric exclusivity
• No active orphan-product market exclusivity
• No Orange Book-listed reference product

The absence of approval is more commercially significant than the historical clinical activity. Clinical-trial results alone do not create a marketable product, a reference listed drug, or an automatic pathway for generic approval.

What is the Orange Book status of talampanel?

Talampanel has no known Orange Book listing because there is no FDA-approved talampanel product. The FDA Orange Book lists approved drug products and associated patent or exclusivity information. An investigational compound that never received approval does not create an Orange Book reference product.

This means there is no conventional Paragraph IV dispute involving a talampanel reference product. A future sponsor would need to pursue a new drug application or another applicable regulatory pathway rather than rely on an abbreviated generic pathway.

What patents protect talampanel?

The original composition-of-matter and development patents for talampanel were filed many years ago. Based on the compound’s early development history, any ordinary U.S. patent term associated with the original molecule would generally have expired or be close to expiration, depending on the priority date, patent family, terminal disclaimers, and patent-term adjustment.

No active commercial patent estate is publicly associated with an approved talampanel product. There is also no current Orange Book patent listing from which to calculate a branded-product loss-of-exclusivity date.

IP category	Current commercial relevance
Original molecule patents	Likely expired or commercially exhausted
Salt or polymorph patents	No established approved-product protection identified
Formulation patents	No marketed formulation with active listing identified
Method-of-use patents	Historical clinical-use claims may exist, but no approved indication is linked to them
Manufacturing patents	No known active manufacturing barrier supporting a commercial product
Orange Book patents	None associated with an approved talampanel product

A patent-by-patent freedom-to-operate conclusion cannot be drawn from the clinical record alone. The practical business conclusion is that talampanel lacks the active product-level exclusivity normally needed to support a major pharmaceutical launch.

Are there Paragraph IV challenges or talampanel patent litigation?

No material Paragraph IV litigation or branded-generic patent dispute is associated with talampanel as an FDA-approved product. The absence of an Orange Book reference product prevents the standard Hatch-Waxman dispute structure that applies to approved drugs.

Historical patent enforcement may have occurred around the underlying chemical series or related AMPA-receptor compounds, but those matters do not create current commercial exclusivity for talampanel. No significant active settlement agreement governing generic launch has been established for a talampanel product.

Which companies developed or challenged talampanel?

Talampanel is associated primarily with Eli Lilly’s early development work and subsequent academic and industry-sponsored clinical evaluation. Public records also connect the compound with later development efforts involving external collaborators.

The competitive challenge came less from direct talampanel patent challengers than from alternative products and mechanisms:

• Perampanel, developed by Eisai, became the leading approved selective AMPA-receptor antagonist.
• Levetiracetam and brivaracetam gained substantial use in focal epilepsy.
• Lacosamide, lamotrigine, and cenobamate strengthened the focal-seizure treatment market.
• Riluzole and edaravone occupied the approved ALS treatment market.
• Temozolomide, tumor-treating fields, radiotherapy, and emerging molecularly targeted approaches shaped glioblastoma treatment.

Perampanel is the most relevant direct pharmacologic comparison, but it is not a generic successor to talampanel and does not share talampanel’s patent estate.

How does talampanel compare with perampanel?

Attribute	Talampanel	Perampanel
Mechanism	Noncompetitive AMPA antagonist	Selective noncompetitive AMPA antagonist
Regulatory status	Investigational; not approved	FDA-approved for epilepsy
Commercial product	None	Commercially marketed
Orange Book listing	None	Yes, subject to applicable product records
Primary market	Historical epilepsy, ALS, glioblastoma research	Focal-onset and generalized tonic-clonic seizures
Development outcome	Discontinued	Established commercial product
Generic risk	No conventional product-level risk	Relevant after applicable exclusivity and patent expiry
Commercial value	None as an active product	Established antiseizure franchise

The comparison shows that target validation does not guarantee product success. Perampanel reached approval with a defined seizure indication and commercial strategy; talampanel did not.

What is the market projection for talampanel?

The base-case market projection is zero branded revenue through the medium term because no sponsor has an active registration program and no approved product exists.

Scenario	Probability assessment	Market implication
No further development	Highest-probability scenario	Zero product revenue
Academic repurposing	Low	Limited investigator-sponsored use, no material commercial market
New epilepsy redevelopment	Low	Requires new efficacy, safety, formulation, and regulatory data
ALS redevelopment	Very low	Prior negative clinical evidence creates a high evidentiary burden
Glioblastoma redevelopment	Very low	Requires biomarker selection and improved clinical rationale
Generic launch	Not applicable currently	No approved reference product

A redevelopment could create value only if a sponsor identifies a differentiated clinical niche, such as a biomarker-defined seizure population or a new formulation with a meaningful pharmacokinetic advantage. Even then, historical data would not substitute for new pivotal evidence.

What generic entry risks exist for talampanel?

There is no conventional generic-entry risk because no FDA-approved talampanel reference product exists. A generic manufacturer cannot rely on an Abbreviated New Drug Application pathway without an approved reference listed drug.

Future competition would arise through one of two routes:

1. A new sponsor obtains approval and later faces generic competition after applicable patents and regulatory exclusivities expire.
2. A different AMPA-receptor antagonist, such as perampanel or a next-generation compound, captures the same clinical market.

Manufacturing is unlikely to be the main barrier. Talampanel is a small molecule rather than a biologic, and no current evidence indicates that complex biologic manufacturing or device technology protects the product. The principal barriers are clinical validation, regulatory approval, market differentiation, and financing.

What licensing or acquisition value does talampanel retain?

Talampanel has limited standalone licensing value. The compound may retain research value for:

• AMPA-receptor pharmacology
• Excitotoxicity studies
• Translational neuroscience
• Combination research in oncology
• Comparative studies against perampanel

A pharmaceutical licensing transaction would require a credible development thesis, new intellectual property, a defined patient-selection strategy, and a sponsor willing to repeat or extend clinical testing. No major active licensing deal has established a current commercial valuation for talampanel.

Key Takeaways

• Talampanel is an investigational AMPA-receptor antagonist with no FDA approval.
• The epilepsy, ALS, and glioblastoma programs did not produce a registrational product.
• The ALS trial failed to show meaningful disease-modifying benefit.
• Talampanel has no Orange Book reference product and no conventional Paragraph IV exposure.
• Original composition-of-matter protection is likely expired or commercially exhausted.
• No active branded revenue or generic market exists.
• Perampanel is the relevant approved comparator, but it is a separate molecule and product.
• The base-case market projection is zero through the medium term.
• Any future value depends on a new sponsor, a new clinical rationale, and new patentable development work.

FAQs about talampanel

Is talampanel still being developed for epilepsy?

No active late-stage development program or FDA registration pathway has been established. Historical epilepsy studies did not result in approval.

Did talampanel fail in ALS?

Yes. Randomized clinical testing did not demonstrate a clinically meaningful disease-modifying benefit sufficient to support continued development.

Is talampanel the same drug as perampanel?

No. Both target AMPA receptors, but they are different chemical entities with different development histories and regulatory status.

Can a generic company market talampanel in the United States?

Not through the standard ANDA route because talampanel has no FDA-approved reference listed drug. A sponsor would need an applicable new-drug regulatory pathway.

Does talampanel have orphan-drug exclusivity?

No current orphan-drug market exclusivity is associated with an approved talampanel product. Historical investigation in ALS did not create a commercial exclusivity period without FDA approval.

References

1. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. U.S. Department of Health and Human Services.

2. Lai, E. C., Felbecker, D. J., Hamilton, M. F., et al. (2009). Talampanel: A novel drug for the treatment of amyotrophic lateral sclerosis. Amyotrophic Lateral Sclerosis, 10(Suppl. 1), 8-13.

3. Rogawski, M. A. (2011). Revisiting AMPA receptors as an antiepileptic drug target. Epilepsy Currents, 11(2), 56-63.

4. U.S. National Library of Medicine. (2024). ClinicalTrials.gov: Talampanel clinical studies. National Institutes of Health.

5. U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drugs database. U.S. Department of Health and Human Services.