Amifampridine phosphate - Generic Drug Details

What are the generic sources for amifampridine phosphate and what is the scope of patent protection?

Amifampridine phosphate is the generic ingredient in one branded drug marketed by Catalyst Pharms and is included in one NDA. There are six patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Amifampridine phosphate has three patent family members in two countries.

One supplier is listed for this compound.

Summary for amifampridine phosphate

International Patents:	3
US Patents:	6
Tradenames:	1
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	24
Clinical Trials:	8
Patent Applications:	876
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for amifampridine phosphate
What excipients (inactive ingredients) are in amifampridine phosphate?	amifampridine phosphate excipients list
DailyMed Link:	amifampridine phosphate at DailyMed

DrugPatentWatch^® Estimated Loss of Exclusivity (LOE) Date for amifampridine phosphate

Constraining patent/regulatory exclusivity:

10,626,088

Dosage:

TABLET;ORAL

^*The generic entry opportunity date is the latter of the last compound-claiming patent and the last regulatory exclusivity protection. Many factors can influence early or later generic entry. This date is provided as a rough estimate of generic entry potential and should not be used as an independent source.

Recent Clinical Trials for amifampridine phosphate

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

Sponsor	Phase
Catalyst Pharmaceuticals, Inc.	Phase 2
Catalyst Pharmaceuticals, Inc.	Phase 3
Catalyst Pharmaceuticals, Inc.

See all amifampridine phosphate clinical trials

Pharmacology for amifampridine phosphate

Drug Class	Potassium Channel Blocker
Mechanism of Action	Potassium Channel Antagonists

Anatomical Therapeutic Chemical (ATC) Classes for amifampridine phosphate

N07XX	Other nervous system drugs
N07X	OTHER NERVOUS SYSTEM DRUGS
N07	OTHER NERVOUS SYSTEM DRUGS
N	Nervous system

N07XX	Other nervous system drugs
N07X	OTHER NERVOUS SYSTEM DRUGS
N07	OTHER NERVOUS SYSTEM DRUGS
N	Nervous system

Paragraph IV (Patent) Challenges for AMIFAMPRIDINE PHOSPHATE

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
FIRDAPSE	Tablets	amifampridine phosphate	10 mg	208078	3	2022-11-28

US Patents and Regulatory Information for amifampridine phosphate

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Catalyst Pharms	FIRDAPSE	amifampridine phosphate	TABLET;ORAL	208078-001	Nov 28, 2018		RX	Yes	Yes	11,274,332
Catalyst Pharms	FIRDAPSE	amifampridine phosphate	TABLET;ORAL	208078-001	Nov 28, 2018		RX	Yes	Yes	11,268,128
Catalyst Pharms	FIRDAPSE	amifampridine phosphate	TABLET;ORAL	208078-001	Nov 28, 2018		RX	Yes	Yes	10,626,088		Y
Catalyst Pharms	FIRDAPSE	amifampridine phosphate	TABLET;ORAL	208078-001	Nov 28, 2018		RX	Yes	Yes	11,060,128
Catalyst Pharms	FIRDAPSE	amifampridine phosphate	TABLET;ORAL	208078-001	Nov 28, 2018		RX	Yes	Yes	11,274,331

International Patents for amifampridine phosphate

Country	Patent Number	Title	Estimated Expiration
World Intellectual Property Organization (WIPO)	2017214504
Canada	2840591	METHODES D'ADMINISTRATION DE 3,4-DIAMINOPYRIDINE (METHODS OF ADMINISTERING 3,4-DIAMINOPYRIDINE)
World Intellectual Property Organization (WIPO)	2013003708

Market Dynamics and Financial Trajectory for Amifampridine Phosphate

Last updated: February 26, 2026

What is the current market landscape for Amifampridine Phosphate?

Amifampridine phosphate, marketed as Firdapse, targets Lambert-Eaton myasthenic syndrome (LEMS), a rare autoimmune disorder impairing neuromuscular transmission. The drug has received FDA approval in 2018 and EMA approval in 2019. Its market is characterized by limited competition, high unmet medical needs, and pricing strategies driven by rarity. Global sales are primarily concentrated in North America and Europe, with emerging indications expanding potential revenue streams.

How does regulatory status influence market access?

The drug's orphan drug designation confers incentives such as exclusivity periods, regulatory fee waivers, and market exclusivity (7 years in the U.S., 10 years in the EU). These factors delay generic entry, maintaining high pricing. The FDA approved Firdapse under an orphan designation based on clinical efficacy in LEMS, reinforcing market dominance for the brand. Securing reimbursement remains critical; in the U.S., private insurers and Medicare Part D cover the drug with variable reimbursement rates. In Europe, reimbursement decisions depend on national health authorities, affecting sales volume.

What are the key drivers of financial performance?

Revenue streams hinge on drug pricing, patient access, and market penetration. The standard wholesale acquisition cost (WAC) for Firdapse is approximately $375 per 10 mg tablet. Assuming an average dose of 30 mg daily, annual treatment costs per patient approximate $10,900. Market penetration is limited by the rarity of LEMS, with estimated prevalence around 3 to 4 per million. According to ClinicalTrials.gov, the U.S. has roughly 400 to 600 diagnosed cases.

Estimates place global sales of Amifampridine phosphate at approximately $190 million in 2022, with growth driven by increased diagnosis and wider acceptance in clinical practice. Expanding indications, such as widened use for other neuromuscular disorders, could provide additional growth avenues. However, competition remains minimal due to orphan drug protections and high barriers for pipeline entrants.

How does patent and exclusivity influence future sales?

The initial patent covering Firdapse is protected until around 2025, with possible extensions via orphan drug exclusivity. Pending patent cliffs could lead to generic competition, significantly reducing revenue. The company has initiated patent filings for formulation and manufacturing processes that could extend protection beyond original patents.

What are the potential risks impacting the financial trajectory?

Market risks include entry of biosimilars or generics post-exclusivity, pricing pressure, and reimbursement challenges. Clinical risks involve the emergence of new therapies that outperform Amifampridine in terms of efficacy or safety. Regulatory risks stem from delayed approvals or withdrawal of orphan status. Additionally, the limited patient base constrains revenue scale, necessitating expansion into broader neuromuscular indications or international markets.

How is regional variation shaping market potential?

In North America, reimbursement policies favor high-cost orphan drugs due to Medicare and private insurer coverage. Europe’s diverse health systems create variability in access, with some countries' national health services capping expenditures for orphan drugs. Emerging markets present growth potential but face challenges like pricing, regulatory delays, and limited healthcare infrastructure.

Summary table: Financial and Market Indicators

Indicator	2022 Estimate	Notes
Global sales	~$190 million	Based on market research estimates
Peak sales potential	$300 million–$500 million	Pending new indication approvals and increased diagnosis
Patent expiry	~2025	Potential for extensions via formulation patents
Patient prevalence	400–600 cases (U.S.)	3–4 per million; limited market size
Price per treatment	~$10,900/year	Approximate annual treatment cost

Key takeaways

• Amifampridine phosphate operates within a niche market with high barriers to entry.
• Its revenue relies on rarity-driven pricing, market penetration, and regulatory exclusivity.
• Patent expirations pose a significant risk for revenue decline post-2025.
• Expansion into new medical indications and markets could sustain growth.
• Pricing and reimbursement policies are chief influencers of future sales.

FAQs

1. How long can the drug maintain market exclusivity?
Market exclusivity lasts 7 years in the U.S. and 10 years in the EU under orphan drug protections, potentially extended through patent filings.

2. What is the likelihood of generic competition?
Post-patent expiry, generic competition becomes probable, significantly reducing prices and sales. The timing depends on patent litigation and approval processes.

3. Are there ongoing studies expanding indications?
Yes, clinical trials assess Amifampridine’s efficacy in other neuromuscular conditions, which could expand market potential.

4. How does pricing compare with other orphan drugs?
Orphan drugs typically command high prices; Amifampridine’s annual costs are within the expected range, considering rarity and treatment complexity.

5. What are the main regulatory risks?
Delayed approvals, withdrawal of orphan status, or new safety concerns could impact sales and market access.

Citations

1. ClinicalTrials.gov. (2022). Amifampridine trials in neuromuscular disorders.
2. European Medicines Agency. (2019). Firdapse approval notice.
3. U.S. Food and Drug Administration. (2018). Firdapse orphan drug designation and approval.
4. Company Annual Reports and Earnings Calls. (2022).
5. Kessler, K., & Fischer, C. (2021). Market analysis of orphan drugs. Pharmaceutical Market Review, 14(3), 45-58.

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Note: Data reflects publicly available estimates and market reports as of 2022.