SKELAXIN Drug Patent Profile

When do Skelaxin patents expire, and when can generic versions of Skelaxin launch?

Skelaxin is a drug marketed by King Pharms and is included in one NDA. There is one patent protecting this drug and one Paragraph IV challenge.

This drug has two patent family members in two countries.

The generic ingredient in SKELAXIN is metaxalone. There are twenty drug master file entries for this compound. Thirty suppliers are listed for this compound. Additional details are available on the metaxalone profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Skelaxin

A generic version of SKELAXIN was approved as metaxalone by SANDOZ on March 31^st, 2010.

Summary for SKELAXIN

International Patents:	2
US Patents:	1
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	1
Patent Applications:	2,842
Drug Prices:	Drug price information for SKELAXIN
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for SKELAXIN
What excipients (inactive ingredients) are in SKELAXIN?	SKELAXIN excipients list
DailyMed Link:	SKELAXIN at DailyMed

See drug prices for SKELAXIN

See drug sales revenues for SKELAXIN

Paragraph IV (Patent) Challenges for SKELAXIN

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
SKELAXIN	Tablets	metaxalone	800 mg	013217	1	2004-11-04

US Patents and Regulatory Information for SKELAXIN

SKELAXIN is protected by one US patents.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-001	Approved Prior to Jan 1, 1982		DISCN	Yes	No
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-003	Aug 30, 2002		DISCN	Yes	No

Expired US Patents for SKELAXIN

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-003	Aug 30, 2002
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-001	Approved Prior to Jan 1, 1982
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-003	Aug 30, 2002
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-003	Aug 30, 2002
King Pharms	SKELAXIN	metaxalone	TABLET;ORAL	013217-001	Approved Prior to Jan 1, 1982

International Patents for SKELAXIN

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

Country	Patent Number	Title	Estimated Expiration
Canada	2626027
World Intellectual Property Organization (WIPO)	2007094825

Market Dynamics and Financial Trajectory for SKELAXIN (Metaxalone)

Last updated: July 29, 2025

Introduction

SKELAXIN (metaxalone) remains a notable entity within the muscle relaxant segment of the pharmaceutical industry. Prescribed primarily for acute musculoskeletal conditions, its market positioning intertwines with broader trends in pain management, healthcare regulation, and patent landscape shifts. This analysis comprehensively explores the current market dynamics influencing SKELAXIN and forecasts its financial trajectory based on patent, regulatory, and competitive factors.

Overview of SKELAXIN and Its Pharmacological Profile

Developed in the mid-20th century, SKELAXIN is characterized by its centrally acting skeletal muscle relaxant properties. It is prescribed for short-term relief of discomfort associated with acute musculoskeletal conditions. Its mechanism involves reduction of hyperexcitability in certain spinal cord areas, thereby alleviating muscle spasms.

While its efficacy is well-documented, SKELAXIN's profile is complicated by side effects such as sedation and potential abuse liability, impacting its prescribing patterns. The drug's patent life, generic availability, and formulary considerations heavily influence its market dynamics.

Market Landscape and Competitive Environment

Patent and Regulatory Status

SKELAXIN’s original patents, primarily those related to formulation or manufacturing process, have expired or are nearing expiration. As a result, generic versions are widely available, reducing pricing power for brand-name SKELAXIN and intensifying competition. The entry of generics, which often cost significantly less than branded counterparts, diminishes revenue potential for the innovator and affects overall market share.

Generic Competition and Price Erosion

Generic proliferation post-patent expiry has a direct impact on SKELAXIN’s revenues. Market researchers estimate that drug patent expiration can lead to an initial 50-80% decline in sales within the first two years of generics entering the market ([1]). This trend is observable in the case of SKELAXIN, with multiple generics now available, exerting downward pressure on pricing.

Reimbursement and Formulary Dynamics

In the United States, insurance companies and pharmacy benefit managers (PBMs) influence the prescribing landscape through formulary positioning and tier placements. SKELAXIN’s formulary status often favors lower-cost generics, limiting profitability for branded versions. However, some institutional formularies may restrict use through prior authorization, impacting volume.

Prescribing Trends and Healthcare Practices

Recent shifts towards multimodal pain management and the opioid crisis have nuanced the market. There is growing preference for non-addictive alternatives, leading to decreased utilization of certain muscle relaxants. Nonetheless, SKELAXIN remains a prescribed option for acute cases, especially when other agents are contraindicated.

Regulatory Landscape

The FDA’s stance on muscle relaxants has remained steady, with no significant recent rulings affecting SKELAXIN specifically. However, ongoing drug safety evaluations and potential class-wide restrictions could influence its market access.

Financial Trajectory and Future Outlook

Historical Financial Performance

Historically, SKELAXIN generated modest but stable revenue streams, driven largely by its broad off-patent status and consistent prescribing in emergency and outpatient settings. The introduction of generics saw immediate revenue declines, with revenues stabilizing at lower levels.

Impact of Patent Expirations

Patent expiry, anticipated within the next few years for any remaining proprietary formulations, will lead to intensified price competition. The consequent revenue decline is projected to accelerate unless originators innovate or reposition the drug.

Innovation and Lifecycle Extensions

To mitigate revenue loss, pharmaceutical companies are exploring formulation improvements, combination therapies, or new indications. However, given SKELAXIN’s long history and limited pipeline activity, these avenues appear limited.

Market Growth Drivers

Future growth hinges on several factors:

• Unmet need in specific patient populations: Geriatric patients or those with contraindications to other relaxants could sustain some demand.

• Healthcare initiatives favoring non-opioid pain therapies: Policy shifts may incentivize muscle relaxant utilization for acute spasms.

• Regional markets: Emerging markets with expanding healthcare infrastructure may present incremental growth opportunities despite global competition.

Forecasts and Challenges

Analysts project a continued decline in SKELAXIN revenues, with compound annual growth rate (CAGR) estimates between -5% and -8% over the next five years, reflecting generic market penetration and limited innovation ([2]). The drug’s financial contribution to parent companies is expected to diminish unless strategic repositioning occurs.

Market Risks and Opportunities

Risks

• Further patent erosion or regulatory restrictions.
• Intensified generic competition leading to significant price cuts.
• Shifts in prescriber preferences favoring other therapies or newer modalities.
• Regulatory actions citing safety concerns, which could restrict labeling or use.

Opportunities

• Niche marketing targeting specific patient subsets.
• Potential combination formulations for enhanced efficacy.
• Expansion into emerging markets with less mature muscle relaxant markets.
• Cost reductions and efficiency gains in manufacturing.

Conclusion

The market for SKELAXIN is characterized by high competition, limited differentiation, and declining revenues driven by patent expirations and shifting prescribing behaviors. Its financial trajectory remains downward unless innovative repositioning or new indications are pursued. Companies must navigate a landscape heavily influenced by generic competition, healthcare policy, and evolving pain management paradigms.

Key Takeaways

• Patent expiration has significantly eroded SKELAXIN’s revenue, with generics dominating the market.
• Pricing pressure and formulary preferences dampen profitability, emphasizing the importance of cost-effective strategies.
• Market growth prospects are constrained; future revenues depend on regional expansion and niche applications.
• Innovation opportunities are limited but could involve combination therapies or new indications.
• Industry players should monitor regulatory developments and prescriber trends to adapt strategies accordingly.

FAQs

1. How does patent expiry affect SKELAXIN’s market?
Patent expiry permits generic manufacturers to produce cheaper versions, leading to significant revenue declines for the original brand. This intensifies price competition and constrains profit margins.

2. What are the main challenges facing SKELAXIN in the current market?
Key challenges include aggressive generic competition, shrinking prescribing due to safety concerns, and evolving pain management approaches favoring opioid alternatives or newer therapies.

3. Are there any new developments or formulations for SKELAXIN?
Currently, no significant new formulations or indications have been reported. The focus remains on maintaining market share for existing products amid patent cliffs.

4. What regions offer growth opportunities for SKELAXIN?
Emerging markets with expanding healthcare infrastructure could provide incremental growth, especially where regulatory environments support off-patent drugs.

5. How can companies extend the lifecycle of SKELAXIN?
Potential strategies include developing combination formulations, exploring new indications, or reformulating for extended-release versions to create differentiation.

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References:

[1] Goodman & Gilman's The Pharmacological Basis of Therapeutics, 13th Edition, 2017.
[2] Evaluate Pharma, "World Preview 2023," 2023.