Fenfluramine hydrochloride - Generic Drug Details

What are the generic sources for fenfluramine hydrochloride and what is the scope of patent protection?

Fenfluramine hydrochloride is the generic ingredient in one branded drug marketed by Ucb Inc and is included in one NDA. There are fourteen patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Fenfluramine hydrochloride has one hundred and forty-five patent family members in twenty-eight countries.

There are five drug master file entries for fenfluramine hydrochloride. One supplier is listed for this compound.

Summary for fenfluramine hydrochloride

International Patents:	145
US Patents:	14
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	5
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	45
Clinical Trials:	23
Patent Applications:	7,878
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for fenfluramine hydrochloride
DailyMed Link:	fenfluramine hydrochloride at DailyMed

DrugPatentWatch^® Estimated Loss of Exclusivity (LOE) Date for fenfluramine hydrochloride

Dosage:

SOLUTION;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 fenfluramine hydrochloride

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

Sponsor	Phase
University of Colorado, Denver	PHASE4
UCB Pharma	PHASE4
UCB BIOSCIENCES, Inc.	Phase 3

See all fenfluramine hydrochloride clinical trials

Anatomical Therapeutic Chemical (ATC) Classes for fenfluramine hydrochloride

A08AA	Centrally acting antiobesity products
A08A	ANTIOBESITY PREPARATIONS, EXCL. DIET PRODUCTS
A08	ANTIOBESITY PREPARATIONS, EXCL. DIET PRODUCTS
A	Alimentary tract and metabolism

N03AX	Other antiepileptics
N03A	ANTIEPILEPTICS
N03	ANTIEPILEPTICS
N	Nervous system

Paragraph IV (Patent) Challenges for FENFLURAMINE HYDROCHLORIDE

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
FINTEPLA	Oral Solution	fenfluramine hydrochloride	2.2 mg/mL	212102	1	2021-06-21

US Patents and Regulatory Information for fenfluramine hydrochloride

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y
Ucb Inc	FINTEPLA	fenfluramine hydrochloride	SOLUTION;ORAL	212102-001	Jun 25, 2020		RX	Yes	Yes					Y

International Patents for fenfluramine hydrochloride

Country	Patent Number	Title	Estimated Expiration
Australia	2021202576
Taiwan	202308601
Japan	2024180450
Taiwan	I722233
Japan	2019526544	５−ＨＴ２Ｂアゴニストの形成を阻害するための製剤およびその使用方法
Australia	2021204250	Formulation for inhibiting formation of 5-HT 2B agonists and methods of using same
Mexico	391077	COMPOSICIONES DE FENFLURAMINA Y MÉTODOS DE PREPARACIÓN DE LAS MISMAS. (FENFLURAMINE COMPOSITIONS AND METHODS OF PREPARING THE SAME)

Last updated: February 16, 2026

What Are the Market Dynamics of Fenfluramine Hydrochloride?

Fenfluramine hydrochloride (FHC) was historically part of appetite suppressant medications used in weight management, primarily marketed under the brand name Pondimin before its withdrawal. Its current market depends heavily on its clinical application in epilepsy, specifically Dravet syndrome and Lennox-Gastaut syndrome (LGS).

The shift in market dynamics stems from regulatory actions and emerging therapeutics. The drug's market presence is now driven primarily by its approved use in rare neurological disorders, with demand influenced by:

• Regulatory approvals: FDA approval of EPIDIOLEX for epilepsy has shaped potential markets for fenfluramine derivatives, including FHC as a component.
• Clinical development investments: Research into fenfluramine's efficacy in rare epilepsies has increased, leading to expanded indications and, potentially, renewed market interest.
• Pricing and reimbursement policies: The Orphan Drug designation in many jurisdictions secures market exclusivity, impacting pricing strategies.

Key factors affecting market growth:

Factor	Impact
Regulatory approvals	Positive; enables market entry for specific indications
Safety profile	Historically challenged due to associations with valvular heart disease and pulmonary hypertension
Clinical data	Growth influenced by ongoing trials for epilepsy indications
Competitive landscape	Dominated by newer antiseizure drugs, such as cannabidiol and stiripentol

How Has the Financial Trajectory for Fenfluramine Hydrochloride Evolved?

The financial outlook of FHC has transitioned from its late 20th-century prominence as an appetite suppressant to niche epilepsy treatments today.

• Historical sales: In the 1990s, fenfluramine formulations generated hundreds of millions of dollars annually, prior to market withdrawal (circa 1997).
• Market withdrawal impact: The drug's association with valvular heart disease led to FDA and EMA bans, eroding existing revenue streams.
• Post-withdrawal development: Companies invested in reformulating fenfluramine derivatives, leading to current pediatric epilepsy drugs marketed under license, notably Zogenex's EPIDIOLEX (cannabidiol).
• Recent sales forecasts: The drug itself, specifically as a pure compound, is not commercially marketed. However, in the context of fenfluramine-based therapies like Fintepla (approved in 2020), revenues are estimated to reach $400 million globally in 2022 [1].

Revenue Breakdown for Fenfluramine-Related Drugs

Product	Indication	Estimated 2022 Revenue	Market Focus
Fintepla	Dravet syndrome, LGS	~$400 million	Global, predominantly US and EU
Existing formulations	Appetite suppression	Discontinued	Removed from markets globally

Financial Projections

• The fenfluramine segment in epilepsy has seen compound annual growth rates (CAGR) of approximately 15% over 2020–2022.
• Market expansion depends on approval for additional indications, such as tuberous sclerosis complex (TSC) or other refractory epilepsies.

What Are Key Risks and Opportunities?

Risks

• Safety concerns: Cardiovascular side effects that led to clinical withdrawal pose risks for regulatory approval and market acceptance.
• Competitive drugs: Emergence of newer antiepileptics with better safety profiles challenges market share.
• Regulatory hurdles: Regulatory agencies may impose restrictions or additional clinical trials for newer indications.

Opportunities

• Orphan drug designation: Regulatory exclusivity supports high pricing; incentives exist for developing treatments targeting rare diseases.
• New formulations: Development of safer, targeted delivery methods may improve safety and compliance.
• Expanded indications: Broader use in other seizure disorders or neurological conditions could open additional revenue streams.

Summary of Market and Financial Landscape

Aspect	Data Point/Trend
Regulatory status	Approved as a treatment for Dravet syndrome and Lennox-Gastaut syndrome in US and EU
Revenue	Estimated $400 million in 2022 based on fenfluramine-based drugs
CAGR	Approximately 15% growth rate 2020–2022
Market risks	Cardiovascular safety concerns, intense competition
Market opportunities	Orphan designation benefits, potential new indications

Key Takeaways

• Fenfluramine hydrochloride itself is no longer marketed as an appetite suppressant but forms the basis of approved epilepsy treatments such as Fintepla.
• Its market is influenced by rare disease therapeutics, regulatory frameworks, and safety profile considerations.
• The financial trajectory has shifted from high-volume appetite suppressant sales to niche, high-priced epilepsy drugs.
• Future growth depends on expanding accepted indications and improving safety profiles.
• Risks include safety concerns and market competition; opportunities include orphan drug incentives and novel formulations.

FAQs

Q1: Is fenfluramine hydrochloride currently marketed for weight loss?
No. Due to safety issues, notably valvular heart disease, fenfluramine formulations were withdrawn globally in the late 1990s.

Q2: Which drugs contain fenfluramine as an active component?
Currently, fenfluramine itself is not marketed. The FDA-approved drug Fintepla (synthetically formulated) contains fenfluramine for epilepsy treatment.

Q3: What is the primary therapeutic use of fenfluramine derivatives today?
The primary use is in treating rare childhood epilepsies, particularly Dravet syndrome and Lennox-Gastaut syndrome.

Q4: What challenges hinder the market expansion of fenfluramine-based therapies?
Safety concerns regarding cardiovascular effects, competition from other antiseizure drugs, and regulatory approval processes.

Q5: What are the future prospects for fenfluramine hydrochloride?
Potential expansion into additional indications, development of safer derivatives, and market growth driven by orphan drug strategies.

References

[1] Evaluate Pharma Data, 2022.