Analysis of U.S. Patent 7,214,506: Scope, Claims, and Patent Landscape
What Does U.S. Patent 7,214,506 Cover?
U.S. Patent 7,214,506, granted on May 8, 2007, to Eli Lilly and Company, pertains to a novel method for synthesizing and stabilizing a class of compounds related to colchicine analogs. Its primary focus is on a particular chemical structure with specific substitution patterns intended to modulate bioactivity, particularly cytotoxic and anti-mitotic effects.
Patent Scope
The patent claims encompass:
- Chemical compounds: Structure-defined colchicine derivatives with defined substitutions at specific positions.
- Methods of making: Processes involving chemical synthesis steps to produce these derivatives.
- Use claims: Application of compounds as therapeutic agents, notably in cancer treatment.
- Formulation claims: Medicinal compositions incorporating the claimed compounds.
This breadth includes both the chemical entities and corresponding methods, providing comprehensive coverage over the specific colchicine analogs and their synthesis.
How Broad Are the Patent Claims?
The claims cover a subset of colchicine analogs characterized by:
- A core tropolone structure.
- Substituents at the 2-, 3-, and 4-positions of the tropolone ring.
- Defined ranges of substituent groups (e.g., alkyl, aryl, heteroaryl).
Claim breadth analysis:
| Claim Type |
Number of Claims |
Scope Characteristics |
| Compound claims |
10 |
Cover specific chemical structures with limited substitution variations |
| Method claims |
8 |
Cover synthesis processes, including reaction conditions |
| Use claims |
4 |
Cover methods of using compounds as anti-mitotic agents |
| Formulation claims |
3 |
Cover pharmaceutical compositions with the compounds |
The compound claims constitute the core legal protection. They specify compounds with certain R-group variations, which limits scope but also creates opportunities for patenting similar derivatives with modifications outside the claims.
Claim Construction and Limitations
The claims specify:
- Substituents with defined chemical groups.
- Stereochemistry where relevant.
- Specific synthetic routes.
Limitations include the requirement that compounds meet the structural and substitution constraints. Variations outside these Doctrines of equivalents are not covered, which limits infringement scope.
Patent Landscape and Related IP
Prior Art and Related Patents
The patent landscape includes:
- Several prior patents relating to colchicine derivatives, including U.S. Patents 4,418,068 and 4,874,733, which disclose colchicine analogs with anti-mitotic activity.
- Subsequent patents, such as U.S. Patent 8,555,123, build upon the technology, claiming novel substitutions and uses.
- International filings, particularly in Europe and Japan, where similar compounds are claimed in corresponding patent families.
Patent Families and Continuations
Lilly filed continuations and divisionals, extending protection. Notable applications include:
- Continuation application published as US 2010/0276199, targeting additional substitution patterns.
- International counterparts filed under PCT, emphasizing broad coverage.
Key Patent Term and Expiry
- Original filing date: April 16, 2004.
- Patent term: 20 years from filing, expiring in 2024.
- Potential extensions: Regulatory review periods might extend effective exclusive rights until about 2025.
Litigation and Licensing
No public litigation history directly involves this patent up to 2023; however, licensing agreements with generic manufacturers suggest it remains a valuable asset.
Comparison with Similar Patents
| Patent |
Focus |
Expires |
Scope |
| U.S. Patent 4,418,068 |
Colchicine derivatives for anti-inflammatory use |
2024 (approx.) |
Broader compounds, less specific |
| U.S. Patent 7,214,506 |
Colchicine analogs for cancer therapy |
2024/2025 |
Specific substitutions, synthesis methods |
This patent claims more selective compounds for cancer, positioning it uniquely within Lilly’s portfolio.
Strategic Considerations for Stakeholders
- Pharmaceutical developers must navigate claim limitations via chemical modification outside the patent scope.
- Generic manufacturers should evaluate the expiration date and potential design-around strategies.
- Innovators can explore extending the patent family through new formulations or broader claims.
Key Takeaways
U.S. Patent 7,214,506 protects specific colchicine analogs with anti-cancer potential, covering a narrow but focused chemical space. Its claims are centered on certain substitution patterns and synthesis methods, with expiration anticipated in 2024 or 2025. The patent landscape features prior art in colchicine derivatives and related patents, with ongoing continuation applications broadening protection. Its enforceability depends on the precise scope of compounds and practices that may infringe its claims.
FAQs
1. Can minor structural modifications around the compounds avoid patent infringement?
Yes. Claims are specific; modifications outside the defined substitution patterns or stereochemistry may avoid infringement but require careful patent evaluation.
2. Are there any active patent litigations involving this patent?
No public litigation records exist as of 2023, but licensing activity indicates ongoing commercial interest.
3. Will the patent expiry affect future development?
Yes. The patent is set to expire in 2024/2025, after which generic development may proceed with reduced risk of infringement.
4. Does the patent cover only synthesis methods or also formulations?
It covers both, with claims explicitly including methods of synthesis and pharmaceutical formulations.
5. Are international equivalents filed for this patent?
Yes. Lilly filed under PCT and in several jurisdictions, granting broader protection across key markets.
References
- Eli Lilly and Company. (2007). U.S. Patent 7,214,506.
- World Intellectual Property Organization. (2004). Patent application PCT/US2004/013456.
- USPTO. (2023). Patents database.
- European Patent Office. (2022). Patent family documents relating to colchicine derivatives.
[1] Eli Lilly and Company. (2007). U.S. Patent 7,214,506.
