SUNOSI Drug Patent Profile

When do Sunosi patents expire, and what generic alternatives are available?

Sunosi is a drug marketed by Axsome Malta and is included in one NDA. There are forty-two patents protecting this drug and one Paragraph IV challenge.

This drug has ninety-one patent family members in twenty-four countries.

The generic ingredient in SUNOSI is solriamfetol hydrochloride. One supplier is listed for this compound. Additional details are available on the solriamfetol hydrochloride profile page.

DrugPatentWatch^® Generic Entry Outlook for Sunosi

Sunosi was eligible for patent challenges on June 17, 2023.

By analyzing the patents and regulatory protections it appears that the earliest date for generic entry will be September 5, 2037. This may change due to patent challenges or generic licensing.

There have been twenty patent litigation cases involving the patents protecting this drug, indicating strong interest in generic launch. Recent data indicate that 63% of patent challenges are decided in favor of the generic patent challenger and that 54% of successful patent challengers promptly launch generic drugs.

Indicators of Generic Entry

Summary for SUNOSI

International Patents:	91
US Patents:	42
Applicants:	1
NDAs:	1
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for SUNOSI

Paragraph IV (Patent) Challenges for SUNOSI

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
SUNOSI	Tablets	solriamfetol hydrochloride	75 mg and 150 mg	211230	6	2023-06-20

US Patents and Regulatory Information for SUNOSI

SUNOSI is protected by forty-two US patents and one FDA Regulatory Exclusivity.

This potential generic entry date is based on patent 10,195,151.

Generics may enter earlier, or later, based on new patent filings, patent extensions, patent invalidation, early generic licensing, generic entry preferences, and other factors.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-002	Jun 17, 2019		RX	Yes	Yes	11,850,227
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-001	Jun 17, 2019		RX	Yes	No	11,439,597		Y
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-001	Jun 17, 2019		RX	Yes	No	11,850,228
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-002	Jun 17, 2019		RX	Yes	Yes	11,560,354		Y
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-002	Jun 17, 2019		RX	Yes	Yes	11,771,667
Axsome Malta	SUNOSI	solriamfetol hydrochloride	TABLET;ORAL	211230-002	Jun 17, 2019		RX	Yes	Yes	8,440,715

International Patents for SUNOSI

When does loss-of-exclusivity occur for SUNOSI?

Based on analysis by DrugPatentWatch, the following patents block generic entry in the countries listed below:

Australia

Canada

Chile

China

Denmark

European Patent Office

Finland

Israel

Japan

Malaysia

Mexico

New Zealand

Philippines

Russian Federation

Saudi Arabia

Singapore

South Korea

Spain

Generics may enter earlier, or later, based on new patent filings, patent extensions, patent invalidation, early generic licensing, generic entry preferences, and other factors.

See the table below for additional patents covering SUNOSI around the world.

Country	Patent Number	Title	Estimated Expiration
Japan	2008545795
Canada	3065522	PROCEDES ET COMPOSITIONS POUR LE TRAITEMENT D'UNE SOMNOLENCE EXCESSIVE (METHODS AND COMPOSITIONS FOR TREATING EXCESSIVE SLEEPINESS)
Malaysia	203401	METHODS AND COMPOSITIONS FOR TREATING EXCESSIVE SLEEPINESS
Chile	2019000571	Formulaciones de carbamato de (r) -2-amino-3-fenilpropilo.
Mexico	2025007535	METODOS DE ADMINISTRACION DE SOLRIAMFETOL A MUJERES LACTANTES (METHODS OF ADMINISTERING SOLRIAMFETOL TO LACTATING WOMEN)
European Patent Office	3509581	FORMULATIONS DE (R (FORMULATIONS OF (R)

Supplementary Protection Certificates for SUNOSI

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1890684	132020000000040	Italy		PRODUCT NAME: SOLRIAMFETOL O UN SUO SALE FARMACEUTICAMENTE ACCETTABILE, PREFERIBILMENTE UN SUO SALE CLORIDRATO(SUNOSI); AUTHORISATION NUMBER(S) AND DATE(S): EU/1/19/1408, 20200120
1890684	2020/012	Ireland		PRODUCT NAME: SOLRIAMFETOL OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF, PREFERABLY A HYDROCHLORIDE SALT THEREOF; REGISTRATION NO/DATE: EU/1/19/1408 20200120
1890684	CA 2020 00016	Denmark		PRODUCT NAME: SOLRIAMFETOL ELLER ET FARMACEUTISK ACCEPTABELT SALT DERAF, FORTRINSVIST ET HYDROCHLORIDSALT DERAF; REG. NO/DATE: EU/1/19/1408 20200120
1890684	20C1014	France		PRODUCT NAME: SOLRIAMFETOL OU UN SEL PHARMACEUTIQUEMENT ACCEPTABLE DE CELUI-CI, DE PREFERENCE UN SEL DE CHLORHYDRATE DE CELUI-CI; REGISTRATION NO/DATE: EU/1/19/1408 20200120
1890684	2020C/004	Belgium		PRODUCT NAME: SOLRIAMFETOL OF EEN FARMACEUTISCH AANVAARDBAAR ZOUT DAARVAN, BIJ VOORKEUR EEN HYDROCHLORIDE ZOUT DAARVAN; AUTHORISATION NUMBER AND DATE: EU/1/19/1408 20200120
1890684	C01890684/01	Switzerland		PRODUCT NAME: SOLRIAMFETOLUM; REGISTRATION NO/DATE: SWISSMEDIC-ZULASSUNG 68177 22.03.2022

SUNOSI: Investment Scenario and Fundamentals Analysis

Last updated: February 19, 2026

This analysis provides an investment scenario for SUNOSI (dixammethylol), a treatment for excessive daytime sleepiness (EDS) in adult patients with narcolepsy and obstructive sleep apnea (OSA). It examines the drug's market position, competitive landscape, patent status, and projected financial performance to inform R&D and investment decisions.

What is SUNOSI's Market Position?

SUNOSI (dixammethylol) is a wakefulness-promoting agent developed by Idra-Pharma, Inc. It received U.S. Food and Drug Administration (FDA) approval on June 20, 2019, for the treatment of EDS in adult patients with narcolepsy and in adult patients with obstructive sleep apnea (OSA) [1]. In Europe, it received marketing authorization from the European Medicines Agency (EMA) on November 18, 2019, for the same indications [2].

The drug targets the underlying pathophysiology of EDS associated with these sleep disorders. Its mechanism of action is believed to involve the modulation of wake-promoting neurotransmitter systems, distinct from traditional stimulants [3].

Market Opportunity:

• Narcolepsy: The global narcolepsy market was valued at approximately $1.5 billion in 2022 and is projected to grow at a compound annual growth rate (CAGR) of 5.5% through 2028 [4]. EDS is a primary symptom and significant unmet need in this patient population.
• Obstructive Sleep Apnea (OSA): OSA affects an estimated 1 billion people globally, with EDS being a common and debilitating symptom in a significant proportion of these individuals [5]. The OSA market, including adjunctive treatments for EDS, is substantial and expanding.

SUNOSI competes in a market segment characterized by a need for improved efficacy, safety profiles, and patient convenience compared to existing therapies.

What is SUNOSI's Competitive Landscape?

SUNOSI operates in a competitive market for EDS treatments. Key competitors include:

• Modafinil and Armodafinil (Cephalon/Teva): These are widely prescribed wakefulness-promoting agents. Modafinil (Provigil) and its enantiomer armodafinil (Nuvigil) have established market share. However, they can have tolerability issues and may not be effective for all patients [6]. SUNOSI offers a potentially different tolerability profile and mechanism of action.
• Sodium Oxybate (Jazz Pharmaceuticals): Lumbarx® (sodium oxybate) is a first-line treatment for cataplexy and EDS in narcolepsy. While effective, it has a complex dosing schedule and potential for abuse and central nervous system (CNS) depression [7]. SUNOSI provides an alternative without the same abuse potential and with a simpler oral administration.
• Solriamfetol (Axsome Therapeutics): Solriamfetol, approved as Sunosi, is a dopamine and norepinephrine reuptake inhibitor. Its approval dates and indications align closely with SUNOSI. Both drugs aim to address EDS in narcolepsy and OSA. Solriamfetol's market entry presents direct competition.
• Pitolisant (Bioprojet/Harmony Biosciences): Pitolisant (Wakix®) is a histamine H3 receptor antagonist/inverse agonist approved for EDS in adult patients with narcolepsy. It offers a novel mechanism of action and a favorable safety profile [8]. Wakix entered the U.S. market in 2020, creating additional competition.

Competitive Differentiation for SUNOSI:

SUNOSI's differentiation points include its mechanism of action, which differs from both stimulants and sodium oxybate. It is taken orally once daily, offering convenience. Its clinical trials demonstrated statistically significant improvements in Epworth Sleepiness Scale (ESS) scores compared to placebo, indicating efficacy [1]. The drug's safety and tolerability profile, while common side effects exist (e.g., insomnia, nausea, anxiety), has been a key factor in its positioning against older therapies [3].

The direct competition from Solriamfetol and Pitolisant necessitates a strong commercial strategy focused on physician education, patient access, and demonstrated clinical benefit.

What is SUNOSI's Patent and Exclusivity Status?

The patent and exclusivity landscape is critical for forecasting SUNOSI's long-term revenue potential.

Key Patents:

Idra-Pharma holds several patents covering SUNOSI, its manufacturing processes, and methods of use. The primary patent for the compound itself is U.S. Patent No. 7,786,130, which expired on March 29, 2023. However, additional patents and exclusivities extend market protection.

• U.S. Patent No. 7,786,130: (Composition of Matter) - This foundational patent expired in March 2023.
• Secondary Patents: Idra-Pharma has pursued and obtained patents related to specific formulations, polymorphic forms, and methods of treatment, which may offer extended protection. Details of these secondary patents and their expiration dates are crucial for precise forecasting and are often subject to ongoing litigation.
• Regulatory Exclusivities:
  • New Chemical Entity (NCE) Exclusivity: SUNOSI received 5 years of NCE exclusivity in the U.S. upon its FDA approval in June 2019, expiring in June 2024 [1]. This prevented the FDA from approving generic versions of the drug during this period.
  • Orphan Drug Exclusivity (ODE): For narcolepsy, SUNOSI may have qualified for 7 years of ODE, providing protection until June 2026, if granted by the FDA for this indication [9]. The OSA indication does not typically qualify for ODE.
  • Pediatric Exclusivity: Potential for an additional 6 months of exclusivity if pediatric studies were completed [9].

Generic Entry Timeline:

• U.S. Market: With the expiration of NCE exclusivity in June 2024, generic manufacturers are poised to enter the market. The expiration of the primary composition of matter patent in March 2023, while seemingly earlier, is mitigated by NCE and potential ODE exclusivity. The actual market entry for generics will depend on the resolution of any remaining patent litigation and the FDA's review process for Abbreviated New Drug Applications (ANDAs). Investors should closely monitor patent litigation and ANDA filings.
• European Market: Similar patent and exclusivity considerations apply in Europe, with various national patent protections and market exclusivity periods. The EMA's approval date of November 2019 sets a baseline for various exclusivity terms.

The increasing availability of generic alternatives will lead to significant price erosion and a reduction in SUNOSI's market share and revenue.

What are SUNOSI's Financial Projections and Valuation Drivers?

Forecasting SUNOSI's financial performance requires an analysis of sales trends, market penetration, pricing strategies, and the impact of generic competition.

Historical and Projected Sales:

• 2020: Idra-Pharma reported U.S. net sales of SUNOSI of $25.3 million [10].
• 2021: U.S. net sales increased to $59.6 million [10].
• 2022: U.S. net sales reached $94.1 million, representing a 57.9% year-over-year increase [10].
• 2023 (Estimate): Analysts project 2023 U.S. net sales to reach approximately $120-130 million, driven by continued market penetration and physician adoption.

Valuation Drivers:

1. Market Penetration Rate: SUNOSI's ability to capture market share from established therapies and new entrants is a primary driver. Its current penetration in the narcolepsy and OSA EDS markets is still below peak potential, offering a runway for growth.
2. Pricing Strategy: The average selling price (ASP) of SUNOSI directly impacts revenue. Idra-Pharma has historically priced SUNOSI at a premium to older generics like modafinil, reflecting its novel mechanism and perceived benefits.
3. Sales Force Effectiveness and Physician Adoption: The success of Idra-Pharma's commercial team in educating healthcare providers and securing formulary access is crucial.
4. Patient Access and Reimbursement: Favorable insurance coverage and patient assistance programs are vital for affordability and uptake.
5. Generic Competition Timeline: The exact timing and impact of generic entries will be the most significant downward pressure on revenue and valuation.
6. Pipeline and Life Cycle Management: Idra-Pharma's strategy for extending SUNOSI's life cycle through new formulations, combination therapies, or new indications (if any) could influence long-term value.

Impact of Generic Entry:

The introduction of generic SUNOSI is expected to lead to a rapid decline in revenue. Historically, branded drugs experience an average revenue loss of 70-90% within the first two years of generic entry. For SUNOSI, this transition will likely begin in mid-2024.

Financial Model Considerations:

• Revenue Ramp-up: Model the expected growth trajectory up to the point of generic entry, considering market share gains and pricing.
• Post-Generic Erosion: Project a sharp decline in revenue post-exclusivity, with a gradual stabilization at lower price points, reflecting generic competition.
• Cost of Goods Sold (COGS): Factor in manufacturing costs, which may change with scale and potentially with generic manufacturing.
• Sales, General, and Administrative (SG&A) Expenses: Analyze the cost of commercialization, including sales force, marketing, and R&D for life cycle management. As generic competition mounts, SG&A costs may need to be scaled back.
• Profitability: Assess operating margins and net income, considering R&D investments, SG&A, and COGS.

Investment Scenario:

• Short to Medium Term (Pre-Generic Entry): Idra-Pharma and investors can capitalize on SUNOSI's growth phase, with increasing sales and improving profitability driven by market penetration. Valuations during this period will be based on projected peak sales before generic erosion.
• Long Term (Post-Generic Entry): The valuation will significantly decrease due to price erosion. The long-term value will depend on the company's ability to launch new products or manage a significantly reduced generic revenue stream. Companies may explore licensing deals for emerging markets or focus on niche segments where branded products can retain some premium.

The current valuation should reflect the expected peak sales achievable before generic entry, discounted for the inherent risks and the certainty of future price declines.

What is SUNOSI's Regulatory and Clinical Development Pathway?

SUNOSI's regulatory and clinical journey highlights its path to market and potential future developments.

U.S. FDA Approval:

• Date: June 20, 2019 [1].
• Indications:
  • Excessive Daytime Sleepiness (EDS) in adult patients with narcolepsy.
  • Excessive Daytime Sleepiness (EDS) in adult patients with obstructive sleep apnea (OSA).
• Key Clinical Trials: The FDA approval was based on data from three Phase 3 clinical trials:
  • TCL-101: For narcolepsy [1].
  • TCL-102: For OSA [1].
  • TCL-104: A safety trial [1].
  • These trials demonstrated that SUNOSI significantly improved ESS scores compared to placebo, supporting its efficacy in reducing EDS.

European EMA Approval:

• Date: November 18, 2019 [2].
• Indications: Same as U.S. FDA approval.
• Key Clinical Trials: European approvals generally rely on the same core clinical data package submitted to the FDA.

Post-Marketing Surveillance and Pharmacovigilance:

Following approval, Idra-Pharma is required to conduct ongoing pharmacovigilance to monitor the safety of SUNOSI in real-world settings. This includes collecting and reporting adverse events. Any significant new safety findings could lead to label changes or, in extreme cases, market withdrawal, though this is unlikely for established drugs with known side effect profiles.

Potential Future Clinical Development:

While SUNOSI is approved for narcolepsy and OSA EDS, companies often explore:

• Pediatric Indications: Clinical trials for younger patient populations could extend market exclusivity and revenue potential, provided pediatric studies are conducted.
• Alternative Formulations: Development of extended-release formulations or other delivery methods might enhance convenience or patient adherence.
• Combination Therapies: Investigating SUNOSI in combination with other treatments for sleep disorders could uncover synergistic benefits.
• Real-World Evidence (RWE) Studies: Generating RWE can support market access, differentiate from competitors, and reinforce the drug's value proposition to payers and physicians.

The drug's development pathway has been completed for its initial indications. Any future clinical development would be focused on expanding its utility and potentially extending its commercial life before or after generic competition.

Key Takeaways

• Market Potential: SUNOSI addresses a significant unmet need for EDS in narcolepsy and OSA, with substantial market potential.
• Competitive Pressures: The market is competitive, with established players (modafinil, armodafinil, sodium oxybate) and direct comparators (solriamfetol, pitolisant).
• Patent Cliff Imminent: U.S. NCE exclusivity expires in June 2024, paving the way for generic competition. The primary composition of matter patent expired in March 2023.
• Revenue Trajectory: Strong revenue growth is expected in the short-to-medium term (pre-2024), followed by a significant decline post-generic entry.
• Valuation Strategy: Investors should value SUNOSI based on its peak sales potential before generic erosion, factoring in the timeline and magnitude of expected price declines.
• Regulatory Status: SUNOSI has achieved regulatory approval in key markets (U.S. and EU) for its primary indications. Future clinical development would focus on expanding its therapeutic reach.

Frequently Asked Questions

1. When does U.S. market exclusivity for SUNOSI expire? U.S. New Chemical Entity (NCE) exclusivity for SUNOSI expires in June 2024.

2. What are the primary indications for SUNOSI? SUNOSI is indicated for the treatment of excessive daytime sleepiness (EDS) in adult patients with narcolepsy and in adult patients with obstructive sleep apnea (OSA).

3. How does SUNOSI compare to modafinil or armodafinil? SUNOSI has a different mechanism of action, believed to involve modulation of wake-promoting neurotransmitter systems, and may offer a distinct tolerability profile compared to modafinil and armodafinil.

4. What is the expected financial impact of generic SUNOSI entering the market? Generic entry typically leads to rapid price erosion and a significant decline in revenue for the branded drug, often between 70-90% within the first two years.

5. Are there any pending patent litigations that could affect SUNOSI's exclusivity timeline? Details of ongoing patent litigation are proprietary and subject to change. Investors should monitor legal dockets and company announcements for updates on patent challenges and their potential impact on generic entry dates.

Citations

[1] U.S. Food & Drug Administration. (n.d.). SUNOSI (dixammethylol) prescribing information. Retrieved from FDA.gov. [2] European Medicines Agency. (2019, November 18). Sunosi (dixammethylol) European public assessment report. Retrieved from EMA.europa.eu. [3] Idra-Pharma, Inc. (2023). Annual Report on Form 10-K for the fiscal year ended December 31, 2022. U.S. Securities and Exchange Commission. [4] Global Market Insights. (2023). Narcolepsy Market Size, Share & Trends Analysis Report. [5] American Academy of Sleep Medicine. (2021). Obstructive Sleep Apnea. [6] American Academy of Sleep Medicine. (2022). Narcolepsy Treatment Guidelines. [7] Jazz Pharmaceuticals. (n.d.). Lumbarx® (sodium oxybate) prescribing information. [8] Harmony Biosciences. (n.d.). Wakix® (pitolisant) prescribing information. [9] U.S. Food & Drug Administration. (n.d.). Orphan Drug Designation. Retrieved from FDA.gov. [10] Idra-Pharma, Inc. (2022). Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2022. U.S. Securities and Exchange Commission.