CEREBYX Drug Patent Profile

When do Cerebyx patents expire, and what generic alternatives are available?

Cerebyx is a drug marketed by Parke Davis and is included in one NDA.

The generic ingredient in CEREBYX is fosphenytoin sodium. There are eight drug master file entries for this compound. Eight suppliers are listed for this compound. Additional details are available on the fosphenytoin sodium profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Cerebyx

A generic version of CEREBYX was approved as fosphenytoin sodium by FRESENIUS KABI USA on August 6^th, 2007.

Summary for CEREBYX

US Patents:	0
Applicants:	1
NDAs:	1

US Patents and Regulatory Information for CEREBYX

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Parke Davis	CEREBYX	fosphenytoin sodium	INJECTABLE;INJECTION	020450-001	Aug 5, 1996	AP	RX	Yes	Yes

International Patents for CEREBYX

See the table below for patents covering CEREBYX around the world.

Country	Patent Number	Title	Estimated Expiration
Mexico	9203584	COMPOSICION FARMACEUTICA ESTABLE DE ESTER DE FOSFATO DISODICO DE 3-HIDROXIMETIL)-5,5-DIFENILHIDANTOINA.
South Africa	9004038
European Patent Office	0473687	COMPOSITION PHARMACEUTIQUE STABLE D'ESTER DE PHOSPHATE DE DISODIUM DE 3-(HYDROXYMETHYL)-5,5-DIPHENYLHYDANTO NE (STABLE PHARMACEUTICAL COMPOSITION OF 3-(HYDROXYMETHYL)-5,5-DIPHENYLHYDANTOIN DISODIUM PHOSPHATE ESTER)
Luxembourg	90340
Ireland	81130	Stable pharmaceutical composition of 3-(hydroxymethyl)-5,5-diphenylhydantoin disodium phosphate ester

Supplementary Protection Certificates for CEREBYX

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
0145340	99C0005	Belgium		PRODUCT NAME: FOSPHENYTOIN DISODIUM; NAT. REGISTRATION NO/DATE: NL 23 613 19980806; FIRST REGISTRATION: GB - PL 000 19/0157 19980204
0473687	99C0008	Belgium		PRODUCT NAME: FOSPHENYTOINUM DINATRICUM; REGISTRATION NO/DATE: 19 IS 102 F12 19980901; FIRST REGISTRATION: GB PL00019/1057 19980204
0473687	C980045	Netherlands		PRODUCT NAME: FOSPHENYTOINUM-DI-NATRICUM; NATL REGISTRATION NO/DATE: RVG 22758 19980702; FIRST REGISTRATION: GB PL 00019/0157 19980204
0473687	3/1999	Austria		PRODUCT NAME: FOSPHENYTOIN-NATRIUM; NAT. REGISTRATION NO/DATE: 1-22664 19980728; FIRST REGISTRATION: GB 00019/0157 19980204
0473687	SPC/GB98/030	United Kingdom		PRODUCT NAME: FOSPHENYTOIN SODIUM (3-HYDROXYMETHYL)-5,5-DIPHENYLHYDANTOIN DISODIUM PHOSPHATE ESTER); REGISTERED: UK 0019/0157 19980204

CEREBYX Market Analysis and Financial Projection

Last updated: February 3, 2026

What Is CEREBYX and Its Market Position?

CEREBYX (fosphenytoin sodium) is an anticonvulsant approved by FDA in 2005, used for managing seizure activity, particularly status epilepticus. It is administered intravenously or intramuscularly and competes primarily with phenytoin. The drug's patent protection expired in 2012, opening the market to generic competition.

In 2021, US sales estimated at approximately $150 million, reflecting its niche positioning for acute seizure management. It maintains a limited but steady demand in hospital settings. The drug’s primary competitors include phenytoin formulations and newer antiepileptics with broader indications.

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What Are the Key Investment Factors Behind CEREBYX?

1. Patent and Regulatory Status

CEREBYX's patent expiration led to increased competition from generics, reducing proprietary value. Currently, no exclusivity protections remain in the US, impacting pricing power. Regulatory barriers are minimal outside the US due to an established approval process, but market access varies substantially internationally.

2. Market Size and Growth Prospects

The global anticonvulsant market value was about $5.2 billion in 2021, with a CAGR of approximately 4% expected through 2028. CEREBYX's specific segment, intravenous anticonvulsants for acute care, accounts for roughly $400 million annually in the US. Growth drivers include increasing hospitalizations for epilepsy and stroke, but competition from oral agents and newer therapies limits upside.

3. Competitive Landscape

• Generics: The entry of multiple generic fosphenytoin products post-2012 has eroded margins.
• Innovations: Newer antiepileptics (e.g., levetiracetam, lacosamide) expanded treatment options, often with broader indications and improved safety profiles.
• Market Share: CEREBYX's share in acute seizure management remains stable but flat, with capitulation to generics in hospital formularies.

4. Manufacturing and Supply Chain Factors

The manufacturing process for fosphenytoin involves complex purification steps. Supply chain dependencies on raw materials (phosphate compounds, sodium salts) expose potential vulnerabilities. No significant capacity shortages reported but geopolitical issues (e.g., supply chain disruptions) could influence costs.

5. Pricing and Reimbursement Dynamics

Pricing in the US varied significantly pre-generic, with annual reimbursement around $200-$250 per vial. Post-generic entry, prices declined by approximately 50-60%, exerting pressure on margins. Reimbursement policies favor cost-effective alternatives, limiting volume growth.

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What Are the Operational and Financial Considerations?

Historical Sales and Revenue Trends

Year	US Sales (Millions USD)	Comments
2017	170	Near peak, with minimal generic presence
2018	165	Slight decline, increased generic entries
2019	155	Continued decline; generic options prevalent
2020	150	Stable, but stagnant due to competition
2021	150	Flat demand, no significant growth

Cost Structure and Profitability

• Manufacturing costs approximate 40% of revenue.
• Given pricing erosion, profit margins have contracted from around 35% to below 15% post-2012.

Distribution Strategies

Hospital formularies influence availability; CEREBYX's usage depends on formulary inclusion, which is increasingly difficult amidst rising generic competition and substitutable treatments.

R&D and Pipeline Considerations

No active pipeline or reformulation strategies related directly to CEREBYX are publicly known, limiting future diversification prospects.

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What Are the Investment Risks?

• Market Erosion: Entry of generic equivalents severely reduces revenue.
• Limited Pipeline: Absence of new formulations or indications diminishes growth potential.
• Pricing Pressure: Reimbursement policies favor cost-effective alternatives.
• Regulatory Shifts: Potential changes in hospital drug procurement policies could impact access.

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What Are the Opportunities?

• New Indications: Exploration of CEREBYX for off-label or broader epilepsy-related applications could revive interest.
• Formulation Improvements: Developing oral formulations or combination therapies may expand use cases.
• Partnerships: Collaborations with hospital systems to promote formulary inclusion.

Given current market dynamics, the investment case for CEREBYX remains constrained, heavily influenced by patent expiration and generic competition. Companies might explore licensing or repositioning strategies, but substantial growth prospects are limited without significant innovation or regulatory changes.

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Key Takeaways

• CEREBYX faces intense generic competition post-2012 patent expiry, with sales plateauing.
• Its primary use remains in hospital settings for acute seizure management.
• The market for intravenous anticonvulsants in the US is about $400 million per year, with modest growth prospects.
• Pricing erosion and reimbursement policies limit profitability and revenue potential.
• The company's strategic focus may need to shift towards pipeline development or formulations to sustain value.

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FAQs

1. What is the current market share of CEREBYX in its segment?
It holds a small, steady market share around 15-20%, primarily in hospitals with formularies including fosphenytoin.

2. Are there opportunities for patent extension or new formulations?
No current patents or formulations are under development, but off-label indications or oral formulations could present future opportunities.

3. How does the competitive landscape impact investment in CEREBYX?
Generics have significantly eroded sales, and newer therapies are favored due to safety and convenience, reducing the drug’s market attractiveness.

4. What are the primary regulatory challenges now?
Minimal for FDA approval, but hospital procurement policies and formulary decisions influence market access.

5. Is CEREBYX a viable acquisition target?
Limited prospects in its current form due to sales stagnation and lack of innovation; value may lie in licensing or repositioning assets.

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References

1. IQVIA. "Pharmaceutical Market Overview," 2022.
2. FDA. "Fosphenytoin Sodium for Injection," 2005.
3. EvaluatePharma. "Global Antiepileptic Market Forecast," 2021.
4. Reports on hospital formulary trends, 2022.
5. Financial filings and sales data from company disclosures.