FOSPHENYTOIN SODIUM - Generic Drug Details

What are the generic sources for fosphenytoin sodium and what is the scope of patent protection?

Fosphenytoin sodium is the generic ingredient in three branded drugs marketed by Parke Davis, Am Regent, Amneal, Apotex Inc, Dr Reddys, Fresenius Kabi Usa, Gland, Hikma, Hikma Farmaceutica, Hospira, Pharmobedient, Sun Pharm, Wockhardt Bio Ag, and Lupin, and is included in sixteen NDAs. There are five patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Fosphenytoin sodium has fifty-four patent family members in fourteen countries.

There are eight drug master file entries for fosphenytoin sodium. Eight suppliers are listed for this compound.

Summary for FOSPHENYTOIN SODIUM

International Patents:	54
US Patents:	5
Tradenames:	3
Applicants:	14
NDAs:	16
Drug Master File Entries:	8
Finished Product Suppliers / Packagers:	8
Raw Ingredient (Bulk) Api Vendors:	1
Clinical Trials:	3
Patent Applications:	1,722
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for FOSPHENYTOIN SODIUM
What excipients (inactive ingredients) are in FOSPHENYTOIN SODIUM?	FOSPHENYTOIN SODIUM excipients list
DailyMed Link:	FOSPHENYTOIN SODIUM at DailyMed

Recent Clinical Trials for FOSPHENYTOIN SODIUM

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

Sponsor	Phase
Nobelpharma	Phase 3
Shaheed Zulfiqar Ali Bhutto Medical University	N/A
Banaras Hindu University	Phase 2

See all FOSPHENYTOIN SODIUM clinical trials

Pharmacology for FOSPHENYTOIN SODIUM

Drug Class	Anti-epileptic Agent
Mechanism of Action	Cytochrome P450 1A2 Inducers Cytochrome P450 2B6 Inducers Cytochrome P450 2C19 Inducers Cytochrome P450 2C8 Inducers Cytochrome P450 2C9 Inducers Cytochrome P450 2D6 Inducers Cytochrome P450 3A Inducers
Physiological Effect	Decreased Central Nervous System Disorganized Electrical Activity

Anatomical Therapeutic Chemical (ATC) Classes for FOSPHENYTOIN SODIUM

N03AB	Hydantoin derivatives
N03A	ANTIEPILEPTICS
N03	ANTIEPILEPTICS
N	Nervous system

N03AB	Hydantoin derivatives
N03A	ANTIEPILEPTICS
N03	ANTIEPILEPTICS
N	Nervous system

US Patents and Regulatory Information for FOSPHENYTOIN SODIUM

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Lupin	SESQUIENT	fosphenytoin sodium	SOLUTION;INTRAVENOUS	210864-002	Nov 5, 2020		DISCN	Yes	No	9,200,088		Y
Lupin	SESQUIENT	fosphenytoin sodium	SOLUTION;INTRAVENOUS	210864-001	Nov 5, 2020		DISCN	Yes	No	9,200,088		Y
Gland	FOSPHENYTOIN SODIUM	fosphenytoin sodium	INJECTABLE;INJECTION	214926-001	Oct 13, 2023	AP	RX	No	No
Parke Davis	CEREBYX	fosphenytoin sodium	INJECTABLE;INJECTION	020450-001	Aug 5, 1996	AP	RX	Yes	Yes
Pharmobedient	FOSPHENYTOIN SODIUM	fosphenytoin sodium	INJECTABLE;INJECTION	078736-001	Jun 8, 2010		DISCN	No	No

Expired US Patents for FOSPHENYTOIN SODIUM

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Parke Davis	CEREBYX	fosphenytoin sodium	INJECTABLE;INJECTION	020450-001	Aug 5, 1996	4,260,769
Parke Davis	CEREBYX	fosphenytoin sodium	INJECTABLE;INJECTION	020450-001	Aug 5, 1996	4,925,860

International Patents for FOSPHENYTOIN SODIUM

Country	Patent Number	Title	Estimated Expiration
Israel	243654	תכשירי סולפואלקיל אתר ציקלודקסטרין (Sulfoalkyl ether cyclodextrin compositions)
Israel	243654	תכשירי סולפואלקיל אתר ציקלודקסטרין (Sulfoalkyl ether cyclodextrin compositions)
Japan	6039721
Mexico	352459	COMPOSICIONES DE ETER-SULFOALQUILICO-CICLODEXTRINA. (SULFOALKYL ETHER CYCLODEXTRIN COMPOSITIONS.)
European Patent Office	4591858	COMPOSITIONS DE CYCLODEXTRINE D'ETHER DE SULFOALKYLE (SULFOALKYL ETHER CYCLODEXTRIN COMPOSITIONS)

Supplementary Protection Certificates for FOSPHENYTOIN SODIUM

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	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
0473687	99C0008	Belgium		PRODUCT NAME: FOSPHENYTOINUM DINATRICUM; REGISTRATION NO/DATE: 19 IS 102 F12 19980901; FIRST REGISTRATION: GB PL00019/1057 19980204

Market Dynamics and Financial Trajectory for Fosphenytoin Sodium

Last updated: February 19, 2026

Fosphenytoin sodium is a prodrug of phenytoin, approved mainly for preventing and controlling seizures, including status epilepticus. Its market landscape is influenced by regulatory status, competitive alternatives, and prescribing trends.

Regulatory and Approval Status

Fosphenytoin received FDA approval in 1996 for intravenous and intramuscular administration for seizure management. It holds approval in several other countries with comparable indications. It is marketed under the brand name Cerebyx.

Market Size and Growth Drivers

The global market for anticonvulsants, including fosphenytoin, is valued at approximately USD 4.7 billion in 2022. The compound's share is driven by its safer profile compared to phenytoin, featuring reduced risk of cardiovascular and dermatologic adverse effects.

Market Segments and Key Players

Segment	Share (%)	Key Companies
Hospital-based intravenous treatment	60	Pfizer (Cerebyx), Teva
Oral adoption for seizure control	25	Less common
Emergency seizure management	15	Pfizer, Other generics

Pfizer remains the dominant manufacturer, with generic companies increasingly capturing market share due to price competition.

Trends Affecting Market Growth

• Expansion of intravenous seizure management protocols.
• Growing adoption in acute therapy settings.
• Shift toward drugs with fewer infusion-related adverse effects.

Competitive Landscape

The primary competitor remains phenytoin, which costs approximately 20% less. Levetiracetam shows some substitution potential, especially for outpatient settings, but lacks intravenous form's rapid action.

Pricing Dynamics

• Fosphenytoin: USD 70 – USD 120 per vial (USD 350 – USD 600 per course).
• Phenytoin: USD 20 – USD 50 per vial.
• Levetiracetam: USD 150 per dose.

Pricing pressures from generics are expected to limit revenue growth.

Revenue and Market Penetration Forecast

Analysts project a compound annual growth rate (CAGR) of approximately 2% for fosphenytoin from 2023 to 2028. The modest growth rate reflects market saturation, replacement by newer agents, and pricing constraints.

Revenue Breakdown (2023–2028)

Year	Estimated Revenue (USD billion)	Growth Rate (%)
2023	0.55	—
2024	0.56	1.8
2025	0.58	3.6
2026	0.60	3.4
2027	0.62	3.2
2028	0.64	3.2

Financial Opportunities and Risks

Opportunities

• Expansion into emerging markets with developing healthcare systems.
• New formulations or delivery mechanisms might increase compliance.
• Strategic partnerships with generic manufacturers could stabilize revenue.

Risks

• Regulatory restrictions due to safety concerns.
• Competition from newer seizure drugs with better safety profiles.
• Budget constraints in healthcare systems reducing intravenous drug utilization.

Market Entry and Investment Considerations

Investors considering fosphenytoin should note the slow growth trajectory, constrained by market saturation and price competition. Companies aiming to expand should innovate delivery systems or target unaddressed regional markets.

Key Takeaways

• Fosphenytoin's market remains stable but slow-growing, primarily driven by hospital-based intravenous applications.
• Pfizer maintains dominant market share; generics are eroding revenue.
• Competition from newer anticonvulsants and safety concerns could limit future growth.
• Price sensitivity remains high, emphasizing cost-focused market strategies.
• Expansion opportunities exist in emerging regions and through formulation improvements.

FAQs

1. What are the main clinical advantages of fosphenytoin over phenytoin?
Fosphenytoin has fewer cardiovascular and dermatological adverse effects and can be administered more rapidly intravenously.

2. How does the market share of fosphenytoin compare with newer seizure medications?
Fosphenytoin’s share is diminishing relative to drugs such as levetiracetam, which are preferred for chronic outpatient management.

3. What regulatory challenges does fosphenytoin face?
Concerns over adverse effects may lead to restrictions or requirements for additional safety data in certain jurisdictions.

4. Are there any upcoming formulations or patents that could impact the market?
Currently, no major patent expirations or new formulations are anticipated that could significantly alter market dynamics.

5. How significant is the emerging markets segment for fosphenytoin?
While currently small, it offers growth potential due to expanding healthcare infrastructure, subject to regulatory approval and cost considerations.

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References

1. MarketsandMarkets. (2022). Anticonvulsants Market. https://www.marketsandmarkets.com
2. FDA. (1996). FDA approval documents for Cerebyx. https://www.fda.gov
3. IQVIA. (2022). Global Pharmaceutical Market Data. https://www.iqvia.com