Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 9,192,579
Introduction
U.S. Patent 9,192,579, granted on November 24, 2015, to Shionogi & Co., Ltd., pertains to a novel class of substituted dihydropyrimidinone compounds with therapeutic applications, primarily in the treatment of viral infections such as influenza. This patent's scope, claims, and subsequent patent landscape offer critical insights for industry stakeholders, including pharmaceutical developers, competitors, and patent analysts.
Scope of U.S. Patent 9,192,579
The patent's scope encompasses specific chemical compounds characterized by a dihydropyrimidinone core with defined substituents, backed by a broad claim set that covers both the compounds themselves and their methods of use. The claims are structured to protect:
- Chemical structures: A class of substituted dihydropyrimidinones with various optional substituents at precise positions, such as halogens, alkyl, and aryl groups.
- Methods of use: Therapeutic methods involving the administration of these compounds for treating viral infections, notably influenza viruses, with detailed dosing and administration routes.
- Pharmaceutical compositions: Formulations comprising the claimed compounds, with excipients and delivery mechanisms.
The patent's language emphasizes chemical diversity within the class while delineating boundaries through specific R-group definitions and substitution patterns. This approach aims to secure broad coverage over derivatives that maintain core pharmacological activity.
Claims Analysis
The patent includes 12 claims, with the following core focus:
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Claim 1: A compound comprising a substituted dihydropyrimidinone core with variable substituents at positions 2, 4, and 5, constrained by specific definitions of R1, R2, and R3 groups, which are selected from a subset of halogens, alkyl, and aryl functionalities. This is an independent claim covering the broad chemical class.
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Claims 2-4: Dependent claims further specify particular preferred substituents for R1, R2, and R3, such as fluorine at R2 and phenyl at R3, providing narrower but commercially valuable claims.
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Claim 5: A method of treating influenza infection with a therapeutically effective amount of the compound claimed in claim 1, emphasizing the invention's utility.
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Claims 6-8: Methods of administration or dosing regimens, potentially covering specific treatment protocols.
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Claims 9-12: Pharmaceutical compositions comprising the compounds, detailing dosage forms such as tablets, capsules, or injectables.
Claim breadth versus patentability: The broad independent claim on the chemical scaffold attempts to maximize protection, but the narrower dependent claims serve to safeguard incremental innovations. Patent examiners would evaluate these claims against prior art to ensure novelty and non-obviousness, yet the detailed substitution pattern provides some robustness.
Patent Landscape Analysis
Analyzing the patent landscape surrounding U.S. Patent 9,192,579 reveals several key elements:
1. Related Patents and Applications
- Several patent families and applications are linked to the core compound class, with filings in jurisdictions such as Japan, Europe, and China, often by Shionogi or licensees.
- Notably, earlier related innovations include compounds like Baloxavir marboxil, which target influenza but differ in chemical class, indicating a competitive landscape in antiviral chemistry.
- Subsequent patent applications post-2015 have sought to expand on this invention by claiming further derivatives, combination therapies, and improved formulations.
2. Competitor Patent Activity
- Companies such as Roche, Gilead, and Sinovac have filed patents related to influenza antivirals, but only a few overlap specifically with the chemical class of dihydropyrimidinones.
- Patent filings focusing on mechanistic innovations, such as targeting viral polymerase or neuraminidase, dominate the landscape, whereas Shionogi's patent emphasizes a distinct chemical scaffold.
3. Patent Expiry and Freedom-to-Operate
- Given the 20-year term from earliest filing, U.S. applications filed prior to 2015 that disclosed similar compounds could have resulted in orphaned patents or prior art references limiting freedom-to-operate.
- Shionogi's patent, granted in 2015, will generally expire around 2035, assuming maintenance fees are paid.
4. Patent Challenges and Litigation
- As of the current date, there have been no publicly reported litigations or post-grant challenges directly targeting this patent.
- However, the competitive landscape has active patent thickets around influenza treatments, which require detailed freedom-to-operate analyses before commercial development.
5. Innovation Trends and Direction
- The chemical class of dihydropyrimidinones remains a focus for antiviral development due to their favorable pharmacokinetics and target specificity.
- Increasingly, patent filings are focusing on combination therapies and delivery systems, suggesting shifts in the innovation landscape beyond mere chemical modifications.
Implications for Stakeholders
- For innovators and licensees, the broad claims on the chemical core provide a strong foundation, but ongoing challenges include overlapping prior art and potential licensing fees.
- For competitors, navigating around these claims necessitates designing structurally distinct compounds or alternative mechanisms.
- For patent strategists, continuous monitoring of subsequent filings and legal developments is essential to secure freedom-to-operate in the antiviral domain.
Key Takeaways
- Broad chemical protection: U.S. Patent 9,192,579 secures extensive coverage over substituted dihydropyrimidinone antivirals, with implications for both current development and future derivative innovations.
- Focused therapeutic claims: The patent’s utility claims provide a clear licensing pathway for influenza treatment, but their enforceability depends on navigating prior art and patenting strategies.
- Competitive landscape: Patent activity around influenza antivirals is intense, with multiple players seeking protection for diverse chemical classes and mechanisms.
- Patent lifecycle considerations: The patent expiry around 2035 underscores the importance of early research and development investment to maintain competitive advantage.
- Innovation focus: Future development will likely involve formulations, combination therapies, and novel derivatives to extend patent life and circumvent existing claims.
FAQs
1. What is the primary therapeutic application claimed in U.S. Patent 9,192,579?
The patent claims the use of substituted dihydropyrimidinone compounds for treating influenza infections by inhibiting viral replication (claim 5).
2. How broad are the chemical scope claims in this patent?
The independent claim (claim 1) covers a wide class of substituted dihydropyrimidinones with variable R-groups, allowing substantial structural diversity within the compound class.
3. Are there any notable competitors with similar patent claims?
While other companies like Roche and Gilead have patent portfolios for influenza antivirals, few directly overlap with the chemical scaffold covered by this patent, though competition exists in mechanisms and formulations.
4. When does this patent expire, and what does that mean for developers?
Patent 9,192,579 is expected to expire around 2035, providing a 20-year window from the filing date, after which generic development and manufacturing can proceed freely, assuming no new extensions or legal challenges.
5. What strategies can competitors adopt to develop around this patent?
Developing structurally distinct compounds outside the scope of the claims, targeting different viral mechanisms, or pursuing alternative chemical scaffolds are common strategies to circumvent the patent.
Sources
[1] U.S. Patent and Trademark Office. U.S. Patent No. 9,192,579.
[2] Shionogi & Co., Ltd. Official patent filings.
[3] Patent Landscape Reports on Influenza Antivirals, 2010–2022.
[4] Industry patent filings and legal case analyses in antiviral space.
