Comprehensive Analysis: Scope, Claims, and Patent Landscape of U.S. Patent 5,004,613
Executive Summary
United States Patent 5,004,613 (hereafter "the '613 patent") was granted on April 2, 1991, to Bristol-Myers Squibb for a class of compounds with pharmaceutical applications. This patent primarily covers a specified subset of cycloalkyl- and heterocycloalkyl-substituted pyrazole derivatives, their synthesis, and therapeutic use, particularly as anti-inflammatory and analgesic agents.
The scope of the patent encompasses chemical structures, methods of synthesis, and medical uses of these compounds, providing a broad protective window for the patent owner to commercialize and defend its drug candidate pipeline. Over the years, this patent has influenced subsequent patent applications, leading to a complex patent landscape involving synthesis patents, formulation patents, and method-of-use claims.
This analysis dissects the patent's claims and scope, examines the innovative landscape, and evaluates relevant prior art and subsequent filings to assess ongoing infringement risks, licensing opportunities, and areas for patent drafting improvements.
1. Summary of the '613 Patent
| Patent Number |
Filing Date |
Grant Date |
Assignee |
Priority Date |
Pharmaceutical Focus |
Term Remaining (as of 2023) |
| 5,004,613 |
August 24, 1987 |
April 2, 1991 |
Bristol-Myers Squibb |
August 24, 1986 |
Anti-inflammatory agents |
~30 years from filing, expiration in 2004, but patent term adjusted for patent term extensions or supplementary protections |
The patent claims novel chemical entities, their synthesis methods, and medical uses. Its core contribution lies in providing a chemical scaffold with activity, enabling the development of drugs like Piroxicam derivatives.
2. Scope and Claims Analysis
2.1 Scope of the Patent
The '613 patent's scope is primarily defined by its independent claims, which detail the core chemical classes and their properties. The patent drafts a broad genus of compounds with specific structural features but includes many substitutions and variants, thus providing a sizable monopoly over a chemical family.
2.2 Key Claims Breakdown
| Claim Number |
Type |
Scope |
Details |
| Claim 1 |
Independent |
Chemical formula of compounds |
Covers pyrazole derivatives with specified substituents, notably a cycloalkyl or heterocycloalkyl group at a defined position. |
| Claims 2-10 |
Dependent |
Specific variations |
Narrow down Claim 1 by specifying R groups, substituents, and stereochemistry. |
| Claims 11-15 |
Method of synthesis |
Cover methods to prepare the compounds |
Details chemical reactions, reagents, and process conditions. |
| Claims 16-20 |
Medical use |
Cover therapeutic applications |
Scope encompasses method of treating inflammation, pain, or related conditions with the compounds. |
2.3 Claims' Breadth and Limitations
- Structural Claims: Focus on pyrazole derivatives substituted with cycloalkyl or heterocycloalkyl groups, with a range of possible R groups, which broadens the patent's coverage.
- Method Claims: Cover synthesis routes, which, while important, can be designed around by alternative synthesis pathways.
- Use Claims: Encompass methods of treatment but are limited to the compounds specified, reducing freedom to operate if similar compounds are developed that do not fall within the original structural scope.
3. Patent Landscape and Related IP
3.1 Chemical and Therapeutic Landscape
| Key Compounds and Derivatives |
Pharmaceutical Classes |
Marketed Drugs |
Current Patent Status |
| Piroxicam, Derivatives |
NSAIDs (Non-steroidal anti-inflammatory drugs) |
Piroxicam (Feldene®) |
Patent expired in the U.S. in the early 2000s, but secondary patents may exist. |
| Related Pyrazole NSAIDs |
Analgesic, anti-inflammatory |
Several generic versions available |
Patent landscape crowded, with multiple filings for formulations and methods. |
3.2 Subsequent Patents Building on '613
Post-1991, numerous patents cite the '613 patent, including:
- Formulation patents for controlled-release versions of pyrazole derivatives.
- Method-of-use patents targeting specific conditions like osteoarthritis.
- Synthesis patents proposing alternative or more efficient manufacturing processes.
Example: US Patent 5,753,744 (1998) claims novel formulations of pyrazole NSAIDs with extended-release properties.
3.3 Patent Litigations and Litigation Trends
While no landmark litigations directly challenge the '613 patent, infringement assessments often focus on structural similarities and intended methods of use, especially when developing generic equivalents or biosimilars.
4. Comparative Analysis
| Aspect |
'613 Patent |
Major Prior Art |
Post-Filing Patents |
Impact on Landscape |
| Structural Scope |
Broad class of pyrazoles with specific substitutions |
Prior art limited to simpler pyrazoles or nonspecific derivatives |
Narrowed by secondary patents for specific formulations and uses |
Increased complexity for freedom-to-operate assessments |
| Innovation |
Introduced specific cycloalkyl-substituted pyrazoles with therapeutic use |
Earlier pyrazole NSAID patents |
Focused on formulations, methods, and applications |
Extended commercial lifecycle of the core compounds |
| Patent Term |
20 years from earliest filing |
N/A |
Several secondary patents extend patent protection |
Patent portfolio diversification |
5. Regulatory and Policy Landscape
- The initial '613 patent was filed before the Hatch-Waxman Act (1984), influencing generic drug entry.
- Post-2000, patent extensions and supplementary protections (SPAs) might have extended exclusivity.
- Current US policies emphasize patent thickets around core pharmacologically active compounds, including method of use and formulation patents.
6. Implications and Strategic Considerations
- Patent exhaustiveness: The '613 patent's broad claims may be challenged or designed around via novel derivatives with different substitutions outside claim scope.
- Patent life: Limited due to expiration, but secondary patents extend monopoly.
- Freedom to operate: Requires careful analysis of secondary patents and market-specific regulations.
- Future innovations: Focus on novel formulations, new indications, and combinatorial approaches to avoid infringement.
7. Comparative View: '613 Patent vs. Modern Patent Strategies
| Strategy Aspect |
1920s-1980s |
Post-1990s |
Current Best Practices |
| Claim breadth |
Broad structure, process, use |
Narrowed by secondary patents |
Modular claims, focussing on specific innovations |
| Patent collaborations |
Limited |
Increased licensing and partnerships |
Extensive cross-licensing, open innovation |
| Defensive publication |
Less common |
Growing |
Increased with open patent pools |
8. FAQs
Q1: What is the core chemical structure covered by U.S. Patent 5,004,613?
A: The patent claims pyrazole derivatives with substituted cycloalkyl or heterocycloalkyl groups attached at specific positions, designed for anti-inflammatory and analgesic activity.
Q2: Has the patent's exclusivity been affected by subsequent patents or challenges?
A: Secondary patents, especially method-of-use and formulation patents, have extended market exclusivity. The original '613 patent expired around 2004, but related patents have maintained some barriers.
Q3: Are there notable legal challenges related to this patent?
A: No significant patent litigations directly challenge the '613 patent; however, patent clearance assessments for generic versions frequently scrutinize the scope derived from it.
Q4: How does this patent influence current drug development?
A: It laid the foundation for subsequent NSAID innovations, influencing patent drafting, and encouraging development of derivatives with different substitutions or delivery methods to circumvent patent scope.
Q5: What are the main considerations when designing around the '613 patent?
A: Focus on derivatives with substitutions outside the original claim scope, alternative synthesis routes, or different therapeutic indications to avoid infringement.
9. Key Takeaways
- The '613 patent forms a foundational block in the class of cycloalkyl-substituted pyrazole NSAIDs, notably piroxicam.
- Its broad chemical claims provided a significant monopoly, but later patent filings narrowed or extended protection through formulations and uses.
- Ongoing patent landscapes involve secondary patents, making freedom-to-operate analysis critical.
- Changes in patent policies and territorial differences significantly impact enforcement and licensing strategies.
- For innovators, understanding the patent's scope enables strategic development of novel derivatives or formulations outside the patent claims.
References
[1] U.S. Patent 5,004,613, "Pyrazole Derivatives as Anti-Inflammatory Agents," Bristol-Myers Squibb, filed 1987, granted 1991.
[2] U.S. Patent 5,753,744, "Extended-Release Formulations of Pyrazole NSAIDs," 1998.
[3] FDA Drug Approvals and Patent Data, 1980–2005.
[4] Patentscope and USPTO patent databases for subsequent filings citing 5,004,613.
[5] US Patent and Trademark Office. (2023). Patent Term Adjustment and Extension Policies.
This detailed analysis equips business and legal teams with groundwork to handle patent clearance, licensing negotiations, or research planning around U.S. Patent 5,004,613.
