Gabapentin enacarbil - Generic Drug Details

What are the generic drug sources for gabapentin enacarbil and what is the scope of patent protection?

Gabapentin enacarbil is the generic ingredient in one branded drug marketed by Azurity and is included in one NDA. There are five patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Gabapentin enacarbil has one hundred and forty-six patent family members in twenty-six countries.

There is one drug master file entry for gabapentin enacarbil. One supplier is listed for this compound.

Summary for gabapentin enacarbil

International Patents:	146
US Patents:	5
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	61
Clinical Trials:	30
What excipients (inactive ingredients) are in gabapentin enacarbil?	gabapentin enacarbil excipients list
DailyMed Link:	gabapentin enacarbil at DailyMed

DrugPatentWatch^® Estimated Loss of Exclusivity (LOE) Date for gabapentin enacarbil

Constraining patent/regulatory exclusivity:

8,795,725

Dosage:

TABLET, EXTENDED RELEASE;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 gabapentin enacarbil

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

Sponsor	Phase
Arbor Pharmaceuticals, Inc.	PHASE4
Azurity Pharmaceuticals	Phase 4
University of Texas at Austin	Phase 4

See all gabapentin enacarbil clinical trials

Pharmacology for gabapentin enacarbil

Physiological Effect

Decreased Central Nervous System Disorganized Electrical Activity

Anatomical Therapeutic Chemical (ATC) Classes for gabapentin enacarbil

N02BF	Gabapentinoids
N02B	OTHER ANALGESICS AND ANTIPYRETICS
N02	ANALGESICS
N	Nervous system

N03AX	Other antiepileptics
N03A	ANTIEPILEPTICS
N03	ANTIEPILEPTICS
N	Nervous system

Paragraph IV (Patent) Challenges for GABAPENTIN ENACARBIL

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
HORIZANT	Extended-release Tablets	gabapentin enacarbil	300 mg and 600 mg	022399	1	2019-04-29

US Patents and Regulatory Information for gabapentin enacarbil

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011		RX	Yes	Yes	6,818,787		Y	Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011		RX	Yes	No	8,795,725		Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011		RX	Yes	Yes	8,795,725		Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011		RX	Yes	No	8,026,279		Y	Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011		RX	Yes	No	6,818,787		Y	Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011		RX	Yes	Yes	8,026,279		Y	Y
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011		RX	Yes	Yes	8,686,034

Expired US Patents for gabapentin enacarbil

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011	6,818,787
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011	8,048,917
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011	8,686,034
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011	8,686,034
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-001	Apr 6, 2011	6,818,787
Azurity	HORIZANT	gabapentin enacarbil	TABLET, EXTENDED RELEASE;ORAL	022399-002	Dec 13, 2011	8,048,917

International Patents for gabapentin enacarbil

Country	Patent Number	Title	Estimated Expiration
South Africa	200602722	CRYSTALLINE FORM OF GAMMA-AMINOBUTYRIC ACID ANALOG
Norway	20083958
Norway	333756
World Intellectual Property Organization (WIPO)	2006050514
Japan	2005529941
China	101381339	Prodrugs of gaba analogs, compositions and uses thereof
Canada	2538802	TRAITEMENT OU PREVENTION DU SYNDROME DES JAMBES SANS REPOS AL'AIDE DE PROMEDICAMENTS A BASE D'ANALOGUES DU GABA (TREATING OR PREVENTING RESTLESS LEGS SYNDROME USING PRODRUGSOF GABA ANALOGS)

Market Dynamics and Financial Trajectory for Gabapentin Enacarbil

Last updated: July 29, 2025

Introduction

Gabapentin enacarbil (brand name: Horizant, among others) is a prodrug of gabapentin, specifically designed to improve pharmacokinetics and bioavailability, addressing limitations of the original gabapentin formulation. Approved by the U.S. FDA in 2011 for the treatment of restless legs syndrome (RLS) and postherpetic neuralgia, its market presence has evolved within the broader neurology and pain management sectors. This analysis explores the underlying market dynamics and financial prospects surrounding gabapentin enacarbil, considering current therapeutic trends, competitive landscape, regulatory developments, and commercialization strategies.

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Market Landscape and Therapeutic Demand

Growing Prevalence of Neurological Conditions

Gabapentin enacarbil targets indications such as RLS and postherpetic neuralgia, both of which are associated with an increasing global patient population owing to aging demographics and rising incidences of neurological disorders. The World Health Organization (WHO) estimates a significant rise in RLS prevalence, especially among older adults, fueling sustained demand for effective treatment options (1).

Limitations of Existing Therapies

While gabapentin has been a cornerstone in neuropathic pain management since its approval in the 1990s, limitations such as variable absorption, frequent dosing requirements, and side effects have framed an opportunity for prodrug formulations like gabapentin enacarbil that promise improved pharmacokinetics, once-daily dosing, and better patient compliance.

Competitive Positioning

Gabapentin enacarbil operates in a competitive landscape composed of generic gabapentin, other FDA-approved agents like pregabalin, and emerging neuromodulation therapies. Its differentiation hinges on pharmacokinetic advantages—better absorption profiles and reduced dosing frequency—factors that impact prescriber preference and patient adherence. Moreover, patent protections as of 2023 continue to influence market exclusivity, although upcoming patent expirations threaten generic competition.

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Regulatory and Commercial Dynamics

Regulatory Frameworks and Approvals

Initially approved in 2011, gabapentin enacarbil's regulatory journey emphasized demonstrated efficacy in RLS and postherpetic neuralgia. The drug underwent additional approvals in select markets, including Japan (2013) and the European Union (lacking approval as of 2023), constrained by regional regulatory assessments and differing clinical data requirements (2). Regulatory reforms favoring abuse-deterrent formulations and better safety profiles could further influence its market trajectory.

Pricing, Reimbursement, and Market Penetration

Pricing strategies for gabapentin enacarbil tend to reflect its positioning as an improved formulation; however, payor reimbursement policies, especially for chronic conditions like RLS, directly affect sales volume. In the U.S., formulary preferences and coverage influence prescribing patterns, with broader insurance coverage correlating with increased utilization.

Patent and Exclusivity Considerations

Patent protections serve as key determinants of revenue potential. As of 2023, patent expiration dates for gabapentin enacarbil are approaching, and generic manufacturers have initiated biosimilar development, potentially leading to significant price erosion. Innovator companies may pursue patent extensions or new indications to lengthen exclusivity periods, yet patent cliffs remain inevitable in the coming years.

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Market Penetration and Revenue Projections

Current Market Share

Since its launch, gabapentin enacarbil captured a notable share within the RLS segment, owing to its convenience and tolerability advantages. However, sales growth has plateaued in some regions owing to generic competition, formulary restrictions, and clinician familiarity with earlier gabapentin formulations.

Future Revenue Trajectory

Analysts forecast moderate growth over the next 3–5 years, driven by expanding indications (e.g., off-label uses like alcohol dependence, where preliminary data suggests benefit), expanding geographic footprint, and increased adoption among neurologists and pain specialists. However, these gains are tempered by impending patent expirations and biosimilar entrants.

Emerging Market Opportunities

Growing healthcare infrastructure and increasing disease awareness in developing markets present new revenue avenues. Regulatory approvals in Asian countries, notably Japan, bode well for market expansion. Conversely, pricing pressures and regulatory hurdles in these regions warrant careful strategic planning.

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Challenges and Opportunities

Challenges

• Generic Competition: Anticipated biosimilar and generic entries will pressure prices and compress margins.
• Regulatory Risks: Divergence in approvals across regions and evolving compliance standards demand strategic agility.
• Market Saturation: In mature markets, the growth rate may plateau unless new indications or formulations are introduced.

Opportunities

• Line Extensions: Investigating new indications such as anxiety, insomnia, or substance use disorders offers growth prospects.
• Partnerships & Collaborations: Licensing agreements and strategic alliances can accelerate market penetration, especially in emerging markets.
• Patient-Centric Innovations: Development of formulations with improved delivery mechanisms—e.g., patches, injectables—may create competitive differentiation.

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Financial Implications

Pharmaceutical companies focusing on gabapentin enacarbil must balance the investment in R&D, marketing, and regulatory activities against expected revenue streams. Given current patent protections and regulatory exclusivity, short-term forecasts predict stable revenues. However, as patent expiries approach, revenue erosion will likely accelerate unless offset by new drug development or lifecycle management strategies.

Investment considerations should factor in the following:

• Market share gains from expanding indications.
• Impact of biosimilar entries on pricing and revenues.
• Pipeline developments that could sustain or augment revenues.
• Pricing and reimbursement policies across different geographies.

Analyst assessments and company financial reports underscore cautious optimism, with diversified pipelines and strategic collaborations acting as mitigants against competitive pressures (3).

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Key Takeaways

• Growing demand: The expanding prevalence of RLS and neuropathic pain conditions sustains therapeutic demand for gabapentin enacarbil.
• Market challenges: Patent expiration risks and increasing generic competition threaten revenue streams.
• Strategic expansion: Pursuing new indications and emerging markets could prolong lifecycle value.
• Regulatory landscape: Variability across regions influences market access and adoption rates.
• Innovation necessity: Future success hinges on lifecycle management and formulation innovation amid pricing pressures.

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FAQs

Q1: What differentiates gabapentin enacarbil from traditional gabapentin?
A1: Gabapentin enacarbil is a prodrug designed for improved bioavailability, allowing for once-daily dosing and better symptom control compared to traditional gabapentin, which has variable absorption and requires multiple daily doses.

Q2: When are generics expected to impact gabapentin enacarbil’s market?
A2: Generic versions are projected to enter the market following patent expirations, anticipated around 2024–2026, which may lead to significant price reductions and loss of exclusivity.

Q3: What are potential new indications for gabapentin enacarbil?
A3: Emerging studies are exploring its use in alcohol dependence, anxiety disorders, and sleep disturbances, which could expand its market beyond initial indications.

Q4: How does regional regulation influence gabapentin enacarbil’s marketability?
A4: Approval status varies; for example, it’s approved in the U.S. and Japan but not in the EU, affecting access, reimbursement, and uptake in different markets.

Q5: What strategies can companies employ to sustain profitability post-patent expiration?
A5: Strategies include developing new formulations, obtaining approvals for additional indications, securing line extensions, and entering emerging markets with tailored pricing strategies.

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References

1. World Health Organization. "Restless Legs Syndrome." WHO Global Health Observatory Data, 2020.
2. U.S. Food and Drug Administration. "FDA approves Horizant for RLS." 2011.
3. MarketWatch. "Pharmaceutical Industry Forecasts." 2023.