Stiripentol - Generic Drug Details

What are the generic sources for stiripentol and what is the scope of freedom to operate?

Stiripentol is the generic ingredient in one branded drug marketed by Biocodex Sa and is included in two NDAs. Additional information is available in the individual branded drug profile pages.

One supplier is listed for this compound.

Summary for Stiripentol

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	2
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	74
Clinical Trials:	15
What excipients (inactive ingredients) are in Stiripentol?	Stiripentol excipients list
DailyMed Link:	Stiripentol at DailyMed

Recent Clinical Trials for Stiripentol

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
Biocodex	PHASE1
Exystat	PHASE3
Biocodex	PHASE3

See all Stiripentol clinical trials

Anatomical Therapeutic Chemical (ATC) Classes for Stiripentol

N03AX	Other antiepileptics
N03A	ANTIEPILEPTICS
N03	ANTIEPILEPTICS
N	Nervous system

US Patents and Regulatory Information for Stiripentol

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Biocodex Sa	DIACOMIT	stiripentol	FOR SUSPENSION;ORAL	207223-002	Aug 20, 2018		RX	Yes	Yes
Biocodex Sa	DIACOMIT	stiripentol	CAPSULE;ORAL	206709-002	Aug 20, 2018		RX	Yes	Yes
Biocodex Sa	DIACOMIT	stiripentol	CAPSULE;ORAL	206709-001	Aug 20, 2018		RX	Yes	No
Biocodex Sa	DIACOMIT	stiripentol	FOR SUSPENSION;ORAL	207223-001	Aug 20, 2018		RX	Yes	No

EU/EMA Drug Approvals for Stiripentol

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Biocodex	Diacomit	stiripentol	EMEA/H/C/000664Diacomit is indicated for use in conjunction with clobazam and valproate as adjunctive therapy of refractory generalized tonic-clonic seizures in patients with severe myoclonic epilepsy in infancy (SMEI, Dravet's syndrome) whose seizures are not adequately controlled with clobazam and valproate.	Authorised	no	no	no	2007-01-03	2009-02-11

Stiripentol Market Dynamics, Financial Trajectory, Patent Protection, and Competitive Risk

Last updated: September 7, 2026

Stiripentol is a niche orphan antiseizure medicine marketed as Diacomit by Biocodex. Its commercial base is concentrated in Dravet syndrome, where it is used with clobazam and valproate or other antiseizure therapy. The product has durable clinical relevance but limited market expansion potential because the addressable population is small, the U.S. orphan exclusivity period has ended, and competing medicines include Epidiolex and Fintepla. Biocodex is privately held and does not publicly report Diacomit revenue, so product-level financial projections require market modeling rather than reported company guidance.

What is stiripentol approved to treat?

Stiripentol is approved for Dravet syndrome, a rare developmental and epileptic encephalopathy characterized by treatment-resistant seizures beginning in infancy.

In the United States, Diacomit is approved for patients at least 2 years old who have Dravet syndrome and are taking clobazam. The FDA approved two oral presentations:

• 250 mg and 500 mg capsules
• 250 mg and 500 mg powder for oral suspension

The recommended total daily dose is 50 mg/kg, divided into three doses, with a maximum of 3,000 mg per day under the U.S. label.[1]

Stiripentol is generally used as adjunctive therapy rather than as monotherapy. Its clinical positioning depends on the clobazam combination, which differentiates it from broader antiseizure drugs.

Where is stiripentol marketed?

Market	Product	Regulatory status	Principal indication
United States	Diacomit	FDA approved in 2018	Dravet syndrome with clobazam, age 2 years and older
European Union	Diacomit	Centralized authorization in 2007	Dravet syndrome with clobazam and valproate
Japan	Diacomit	Approved for Dravet syndrome	Adjunctive treatment for refractory seizures
Other countries	Diacomit or local registrations	Country-specific	Primarily rare epilepsy and Dravet syndrome

The European authorization predates the U.S. approval by more than a decade. This established international treatment experience, physician familiarity, and a regulatory record before the U.S. launch.[2]

How large is the stiripentol market?

The commercial market is small in patient count but high in treatment value per patient. Dravet syndrome is estimated to affect approximately 1 in 15,000 to 1 in 40,000 births, although prevalence estimates differ by methodology and case definition.[3]

The principal market variables are:

1. The number of diagnosed Dravet patients.
2. The share receiving clobazam-based treatment.
3. Pediatric diagnosis and referral rates.
4. Long-term treatment persistence.
5. Reimbursement for orphan drugs.
6. Competition from newer Dravet therapies.

The United States is the highest-value market because of orphan-drug pricing and concentrated specialty prescribing. Europe provides a broader geographic base but operates under country-level reimbursement controls and reference pricing. Japan and selected international markets add volume but generally contribute less revenue per patient than the United States.

What is the estimated patient opportunity?

No authoritative public source provides a current global Diacomit patient count. A reasonable commercial framework is:

Variable	Market implication
Rare-disease prevalence	Limits absolute patient volume
Pediatric onset	Supports early diagnosis but creates care-transition challenges
Chronic use	Supports recurring revenue and retention
Adjunctive positioning	Limits use to patients meeting regimen and severity criteria
High unmet need	Supports continued reimbursement despite small population
Newer competitors	Limits incremental share expansion

Stiripentol has a concentrated revenue base. A relatively small change in diagnosis, reimbursement, or treatment sequencing can materially affect annual sales.

What is the financial trajectory for Diacomit and stiripentol?

Biocodex does not publish audited, product-specific Diacomit revenue in the manner of a publicly traded pharmaceutical company. Public financial disclosure therefore does not establish a verified annual revenue series for stiripentol.

The financial trajectory is best characterized as mature and defensive rather than high-growth:

• U.S. launch expansion supported growth after 2018.
• The rare-disease indication supports high revenue per treated patient.
• The patient pool limits volume-driven growth.
• Competition has increased since the introduction of Epidiolex and Fintepla.
• Loss of U.S. orphan exclusivity increases long-term pricing and generic risk.
• Continued geographic expansion can offset slower growth in established markets.

What drives stiripentol revenue?

Revenue depends on treatment duration, dosing weight, payer coverage, and the number of eligible patients. Because the drug is dosed by body weight, revenue can rise as pediatric patients grow even when patient counts remain stable. The same feature increases payer scrutiny and creates a larger economic burden for older or heavier patients.

The commercial model also benefits from chronic use. Patients who respond adequately to stiripentol may remain on therapy for years, particularly where physicians have limited alternatives. Treatment discontinuation can result from inadequate seizure control, adverse effects, drug interactions, or transition to newer therapies.

Biocodex’s private ownership reduces visibility into:

• Net sales
• Gross-to-net deductions
• Regional revenue
• Research and development spending
• Product profitability
• Sales and marketing investment
• Pipeline contribution from the stiripentol franchise

When does stiripentol lose exclusivity in the United States?

The FDA granted Diacomit orphan-drug exclusivity for seven years following U.S. approval on August 20, 2018. The seven-year period therefore reached its scheduled end on August 20, 2025, subject to the statutory conditions governing orphan exclusivity.[4]

FDA orphan exclusivity prevents approval of the same drug for the same disease or condition during the exclusivity period, with limited statutory exceptions. It is separate from patent protection and does not necessarily prevent all forms of competition.

Stiripentol exclusivity timeline

Event	Date
European Union authorization	2007
U.S. FDA approval	August 20, 2018
U.S. orphan exclusivity scheduled end	August 20, 2025
U.S. post-exclusivity period	Begins after the orphan period ends, subject to applicable FDA review and patent status

The expiration of orphan exclusivity does not guarantee immediate generic launch. An ANDA applicant must satisfy FDA requirements, address any listed patents, and obtain approval. Commercial launch also depends on manufacturing readiness, reimbursement, and the expected size of the market.

What patents protect stiripentol and Diacomit?

Stiripentol is an older small molecule, and broad compound patent protection is not expected to provide a current long-duration barrier comparable to a recently discovered drug. The principal late-life protection issues are more likely to involve:

• Product-specific formulation claims
• Powder-for-suspension technology
• Manufacturing processes
• Treatment regimens
• Combination use with clobazam
• Pediatric dosing or administration methods
• Country-specific regulatory exclusivity

The clinical formulation and method-of-use landscape is more commercially relevant than the underlying compound itself. Any patent covering the active ingredient would need to be evaluated against its filing date, term adjustment, terminal disclaimers, and jurisdiction-specific enforceability.

What formulations are protected by stiripentol patents?

Diacomit is marketed in capsules and powder for oral suspension. The powder formulation has practical value in pediatric patients who cannot swallow capsules and may support treatment initiation in very young patients.

Formulation protection can delay direct substitution if claims cover a specific composition, dissolution profile, stability characteristic, or manufacturing process. It is less effective if a generic applicant can develop a non-infringing formulation with equivalent quality and bioavailability.

Are there method-of-use patents for stiripentol?

The most commercially important use is adjunctive treatment of Dravet syndrome with clobazam. Method-of-use rights may cover a disease, patient population, dosing regimen, or combination therapy. Their value depends on claim scope and whether the relevant use is carved out from a generic label.

A generic applicant may seek a skinny-label strategy that omits patented uses while retaining approval for non-protected indications. For stiripentol, the narrow indication means a use carve-out could be commercially difficult if most demand is tied to the Dravet-clobazam regimen.

What is the Orange Book status of Diacomit?

Diacomit is an FDA-approved prescription drug subject to Orange Book review. The Orange Book identifies approved products, therapeutic equivalence information, and, where applicable, patent and exclusivity data.[5]

The key commercial issue is whether active, unexpired U.S. patents are listed for the relevant Diacomit products. Orphan exclusivity and Orange Book patent listings are separate rights. The end of orphan exclusivity removes one regulatory barrier but does not eliminate a valid patent barrier.

A Paragraph IV certification could challenge an asserted patent before expiration. The patent holder may respond with litigation under Hatch-Waxman, potentially triggering a 30-month stay of approval for an ANDA under applicable statutory conditions.[6]

Which companies are challenging stiripentol?

No major publicly documented Paragraph IV litigation campaign has established a visible generic challenge to Diacomit comparable to the litigation surrounding large primary-care drugs. The absence of a public challenge does not mean that generic development is impossible. It indicates that the addressable market, formulation requirements, regulatory complexity, or expected returns may not yet justify a large-scale challenge.

Potential challengers would most likely include:

• Specialty generic manufacturers
• Companies with pediatric oral suspension capabilities
• Regional pharmaceutical manufacturers seeking U.S. entry
• Contract development and manufacturing organizations with rare-disease expertise

The narrow patient population creates an unusual competitive structure. A first generic entrant could gain substantial share, but the total market may not support many competitors.

What is the biosimilar risk for stiripentol?

There is no biosimilar risk because stiripentol is a small-molecule drug, not a biologic. Competition would arise through the ANDA generic pathway rather than the biosimilar pathway under the Public Health Service Act.

This distinction matters commercially:

• Generic applicants generally rely on bioequivalence rather than clinical similarity studies.
• The approval pathway can be less costly than biosimilar development.
• Formulation and labeling issues may still complicate entry.
• A generic may face patent litigation or regulatory exclusivity barriers.

How does stiripentol compare with Fintepla and Epidiolex?

Stiripentol competes with other Dravet therapies but has a distinct treatment position.

Product	Active ingredient	Manufacturer	FDA approval	Position in Dravet syndrome
Diacomit	Stiripentol	Biocodex	2018	Adjunctive therapy with clobazam
Epidiolex	Cannabidiol	Jazz Pharmaceuticals	2018	Dravet syndrome, Lennox-Gastaut syndrome, tuberous sclerosis complex
Fintepla	Fenfluramine	UCB, formerly Zogenix	2020	Dravet syndrome and Lennox-Gastaut syndrome

Epidiolex has a broader epilepsy label and benefits from multiple disease indications. Fintepla has direct competition with stiripentol in Dravet syndrome and may be used with or without clobazam, depending on clinical practice and label requirements.[7][8]

Stiripentol retains several commercial advantages:

• Long clinical experience in Dravet syndrome
• Established use with clobazam
• International availability
• Familiarity among specialist epilepsy centers
• A defined role in treatment algorithms

Its disadvantages include:

• Narrow disease scope
• Significant drug-interaction management
• Weight-based dosing
• Competition from drugs with broader labels
• Reduced exclusivity protection after 2025

What litigation and settlement risks affect stiripentol?

Publicly visible litigation risk appears lower than for major blockbuster drugs because the product has a limited revenue pool and no widely reported high-value patent dispute. The principal future litigation scenarios are:

1. A Paragraph IV challenge against listed formulation or method patents.
2. A Biocodex suit seeking a 30-month stay.
3. A settlement that delays generic launch.
4. Patent litigation over a pediatric powder formulation.
5. Regulatory litigation involving the scope of orphan exclusivity.

No major publicly reported settlement has established a known generic launch date for Diacomit. A settlement would be commercially important because even a delayed generic could reduce expected post-exclusivity revenue.

What generic launch scenarios exist for stiripentol?

Scenario 1: No near-term generic

Biocodex retains the market after orphan exclusivity because no applicant completes development or challenges relevant patents. This scenario supports continued revenue but exposes the product to eventual price pressure.

Scenario 2: One first generic entrant

A single approved generic captures a large share of volume through discounting and payer substitution. Biocodex may preserve part of the market through physician familiarity, supply reliability, or patient-support programs.

Scenario 3: Multiple generic entrants

Several manufacturers enter after patent barriers expire. Price erosion accelerates, particularly for capsules. The powder-for-suspension product may retain stronger economics if it has greater formulation or manufacturing complexity.

Scenario 4: Authorized generic or settlement launch

Biocodex or a commercial partner launches an authorized generic, or a settlement permits entry on a negotiated date. This can reduce third-party generic upside while preserving some manufacturer control over pricing.

How strong is the stiripentol patent estate?

The patent estate is commercially meaningful but unlikely to be considered a broad, long-duration monopoly. Its strength depends on the claims covering the marketed formulation and the ability to enforce them against a generic product.

Patent-estate factor	Assessment
Compound protection	Likely weak or expired because stiripentol is an older molecule
Orphan exclusivity	U.S. period scheduled to end in 2025
Formulation protection	Potentially important for powder and pediatric administration
Method-of-use protection	Relevant to the clobazam combination and Dravet syndrome
Manufacturing protection	May create operational barriers but usually does not block all substitutes
Generic vulnerability	Moderate to high after loss of orphan protection
Biosimilar exposure	None

The strongest barriers may be operational rather than legal. Pediatric oral formulations require reliable manufacturing, taste acceptance, stability, distribution, and specialty pharmacy support. These factors can delay entry even when patent protection is limited.

What is the commercial outlook for stiripentol?

Stiripentol should remain a durable niche product rather than a high-growth asset. Revenue is likely to be supported by chronic treatment, specialist prescribing, and continued unmet need in Dravet syndrome. Growth is constrained by a small patient population, competitive therapies, and the end of U.S. orphan exclusivity.

The most material value drivers are:

• Retention of patients already controlled on stiripentol
• Continued reimbursement in the United States and Europe
• Expansion of diagnosis and referral to epilepsy centers
• Preservation of the clobazam-based treatment position
• Successful defense of formulation or use patents
• Absence of an early generic entrant

The main downside risks are generic substitution, payer pressure, loss of share to Fintepla or Epidiolex, and limited transparency into Biocodex’s commercial investment and product-level profitability.

Key Takeaways

• Stiripentol is a specialized Dravet syndrome therapy marketed as Diacomit by Biocodex.
• The U.S. product was approved on August 20, 2018, with seven years of orphan exclusivity scheduled to end on August 20, 2025.
• Biocodex does not publicly disclose audited Diacomit revenue, preventing a verified product-level financial history.
• The market is small in patients but economically attractive because treatment is chronic and orphan-drug pricing is high.
• Fintepla and Epidiolex are the principal branded competitive threats.
• Stiripentol has no biosimilar risk because it is a small molecule.
• Generic risk becomes more material after the end of U.S. orphan exclusivity, especially if no enforceable formulation or method-of-use patents remain.
• The powder-for-suspension formulation may create greater practical entry barriers than the capsule product.
• The asset is commercially defensive but has limited structural growth and increasing post-exclusivity exposure.

FAQs About Stiripentol Market and Patent Risk

Does stiripentol have blockbuster potential?

No. The Dravet syndrome population is too small to support conventional blockbuster scale, although the product can generate substantial orphan-drug revenue per treated patient.

Is stiripentol a controlled substance?

No. Stiripentol is not generally classified as a controlled substance. Its principal regulatory and clinical concerns involve drug interactions, adverse effects, and seizure-treatment monitoring.

Can stiripentol be used without clobazam?

The U.S. FDA indication is tied to use with clobazam. Use outside the labeled regimen may occur clinically but does not carry the same regulatory positioning as the approved indication.

Which drug is the strongest competitor to stiripentol?

Fintepla is the most direct branded competitor in Dravet syndrome. Epidiolex is also important because it has a broader epilepsy label and can be prescribed across several severe epilepsy syndromes.

Will generic stiripentol immediately replace Diacomit?

Not necessarily. Generic substitution depends on FDA approval, patent status, formulation equivalence, payer policy, supply reliability, and whether a generic can adequately serve pediatric patients requiring oral suspension.

References

1. U.S. Food and Drug Administration. (2024). Diacomit (stiripentol) prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/209363s006,209364s006lbl.pdf

2. European Medicines Agency. (2024). Diacomit: EPAR - product information. https://www.ema.europa.eu/en/medicines/human/EPAR/diacomit

3. National Organization for Rare Disorders. (2024). Dravet syndrome. https://rarediseases.org/rare-diseases/dravet-syndrome/

4. U.S. Food and Drug Administration. (2024). Orphan drug designation and exclusivity. https://www.fda.gov/industry/developing-products-rare-diseases-conditions/orphan-drug-designation-and-exclusivity

5. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book

6. U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act of 1984, 21 U.S.C. § 355.

7. U.S. Food and Drug Administration. (2024). Epidiolex prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/210365s022lbl.pdf

8. U.S. Food and Drug Administration. (2024). Fintepla prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/212102s009lbl.pdf