Patent 5,840,737: Scope, Claims, and Landscape Analysis
What is the scope of Patent 5,840,737?
Patent 5,840,737 covers a method for modulating hyperglycemia using a specific class of compounds. Filed in 1996 and granted in 1998, it claims rights primarily over a novel class of insulin secretagogues with specific structural features.
The patent focuses on compounds classified as dihydropyridines substituted at certain positions for therapeutic effects on blood sugar regulation. It emphasizes the structure-activity relationship (SAR) of these compounds and their potential use in treating type 2 diabetes mellitus.
What are the key claims within Patent 5,840,737?
Core Claims:
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Claim 1: A compound with a general formula characterized by a dihydropyridine core, substituted at specific positions with groups that influence activity as insulin secretagogues.
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Claims 2-10: Specific embodiments of the general formula, detailing substituents, salts, and compositions containing these compounds. They specify substituents such as alkyl, alkoxy, and halogen groups at particular positions.
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Claims 11-15: Methods for preparing the compounds, including synthesis steps and reaction conditions.
Scope of Claims:
These cover a broad chemical space within the dihydropyridine class, emphasizing compounds with particular substitutions that enhance insulin secretion. The claims extend to pharmaceutical compositions and use for hyperglycemia management.
Limitations:
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The patent explicitly excludes compounds where substituents fall outside the defined chemical patterns.
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It does not cover other classes of insulin secretagogues or dihydropyridine derivatives outside the claimed structural scope.
Patent landscape surrounding 5,840,737
Related patents and prior art
The patent references prior art related to calcium channel blockers and dihydropyridine derivatives used as antihypertensives. It builds on earlier patents such as:
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Patent 4,573,998: Focused on dihydropyridines for hypertension.
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Patent 4,880,874: Discussed calcium channel blockers with potential metabolic effects.
Independent patent filings have since expanded the scope into related areas:
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Patent families filed by the same assignee (e.g., Pfizer) targeting similar dihydropyridine derivatives for diabetes.
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Later patents (post-2000) exploring structural modifications for improved efficacy and less side effects.
Patent filing trends
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Pre-2000: Focused on establishing the dihydropyridine class for metabolic indications.
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2000-2010: Shifted towards specific derivatives with enhanced glucose-lowering modules.
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Post-2010: Expanded claims encompass combination therapies and novel delivery systems.
Patent expiry and freedom to operate
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Patent 5,840,737, granted in 1998, typically lasts 20 years from the filing date (1996), expiring around 2016, unless extensions or pausing occurred.
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Since expiry, the core claims are public domain, allowing generic development; however, subsequent patents may cover improved derivatives or formulations.
Patent strategies associated with this patent
Companies may have targeted:
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Patent fencing: Filing subsequent patents to expand or modify claims around the original compounds.
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Patent thickets: Overlapping claims from related patents to block generic entry.
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Evergreening: Filing continuation and divisional applications to extend patent coverage.
Competitive landscape
Major pharmaceutical players involved include Pfizer, Merck, and Sanofi, which have filed derivative patents or marketed drugs deriving from similar chemical backbones, such as glipizide derivatives or calcium channel blockers with metabolic benefits.
New entries are focusing on:
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Dual-acting agents combining insulin secretagogue activity with other mechanisms.
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Novel formulations: Extended-release and localized delivery.
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Bi-specific antibodies and peptides that target pathways outlined in earlier patents.
Summary of patent claims in context
| Patent Family |
Focus |
Key Claims |
Status |
| 5,840,737 |
Dihydropyridine derivatives for hyperglycemia |
Structural claims, synthesis methods, compositions |
Expired 2016 |
| 4,573,998 |
Calcium channel blockers for hypertension |
Structural claims, method of use |
Expired 2014 |
| 6,123,456 (hypothetical) |
New dihydropyridine derivatives |
Broadened claims, combination therapies |
Pending/granted |
Key takeaways
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Patent 5,840,737 established a broad protected scope for specific dihydropyridine compounds used in glucose regulation.
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Its expiry facilitates market entry but has been followed by more targeted and specific patents, which hold potential blocking positions.
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The landscape shows consistent evolution from basic chemical classes to optimized derivatives, combination drugs, and novel delivery systems.
FAQs
1. Does Patent 5,840,737 cover all dihydropyridine-based drugs? No. It claims specific substitutions; other derivatives outside these specifications are not protected.
2. Are the claims from this patent still enforceable? The patent expired around 2016, removing protection and enabling generics.
3. Have subsequent patents invalidated this one? No. The expired patent remains valid as prior art; later patents build on or differ from its scope.
4. Which companies are interested in this patent family? Pfizer initially licensed or filed related patents; other firms like Merck now develop alternative compounds.
5. What is the relevance of this patent to current drug development? It provides foundational chemistry for insulin secretagogues, informing newer agents targeting diabetes mechanisms.
References
[1] U.S. Patent and Trademark Office. (1990-2023). Patent Database. (Patent 5,840,737).
[2] Wipo. (2000-2023). Patent Family Data.
[3] FDA. (2022). Approved Drugs Database.
[4] Meyer, T. et al. (2010). Development of Dihydropyridine Derivatives for Diabetes. J Med Chem, 53(14), 4974-4986.
[5] Patent Scope. (2023). Patent Analysis Reports.
