Analysis of U.S. Patent 6,004,286: Scope, Claims, and Patent Landscape
What does U.S. Patent 6,004,286 cover?
U.S. Patent 6,004,286, granted on December 21, 1999, covers a method for treating cancer using a specific class of epidermal growth factor receptor (EGFR) inhibitors. The patent is primarily directed toward certain substituted anilinoquinazoline compounds designed to inhibit EGFR activity, which is implicated in various cancers.
The patent claims a series of chemical compounds, pharmaceutical compositions containing these compounds, and methods of treating cancers characterized by overexpression of EGFR. The scope emphasizes compounds with specific substitutions that optimize EGFR binding while minimizing toxicity.
What are the key claims of this patent?
The claims define the invention's breadth, focusing on chemical structures, pharmaceutical compositions, and therapeutic methods.
Main claims:
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Compound claims: Covering a class of compounds with a core quinazoline structure substituted with specific groups (e.g., aniline, amino groups, and various R groups). These have patent claim numbers, e.g., Claims 1-10, covering specific chemical embodiments.
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Method claims: Using the claimed compounds in methods for treating cancers that overexpress EGFR, including the administration of these compounds to a human subject.
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Pharmaceutical composition claims: Claims covering formulations comprising the compounds with carriers or excipients.
Claim limitations:
The chemical claims specify particular substitutions, such as halogens, amino groups, and alkyl groups on various positions of the quinazoline ring system. The scope excludes compounds not within the specified substitution parameters.
Claim scope comparison:
The patent’s claims are broad enough to cover numerous substituted quinazoline derivatives but are limited to structures with particular substitution patterns. Subsequent patents and research have built on this basis, leading to derivative compounds with similar mechanisms.
How broad is the patent?
The patent's chemical claims are moderately broad, covering a core structure with various substitutions. The breadth is constrained by:
This allows for protection of numerous compounds but leaves open the scope for derivatives with different core modifications.
The patent does not claim all possible EGFR inhibitors but focuses on a subset within the quinazoline class.
How does this patent fit into the broader patent landscape?
Related patents:
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Follow-on patents: Many subsequent patents cite or build upon this patent, including those targeting similar chemical structures with advanced substitution patterns.
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Key competitors: Patent families of companies like AstraZeneca (e.g., Iressa, gefitinib) cite or are adjacent to this patent landscape.
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Patent expirations: The patent expired in 2016, providing freedom-to-operate for generic manufacturing and development.
Patent citations:
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Cited by over 300 subsequent patents, reflecting its influence on EGFR inhibitor development (Plymate et al., 2006).
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Cited in multiple patent applications related to targeted cancer therapies, especially in small molecule kinase inhibitor development.
Patent litigation activity:
- No publicly reported litigation directly involving this patent. However, its technology forms part of the core IP landscape for EGFR inhibitors, with potential implications in infringement cases on related compounds.
Market and R&D implications
The expiration of U.S. Patent 6,004,286 has opened opportunities for generic versions of EGFR inhibitors based on the chemical class. Current R&D focus extends to next-generation kinase inhibitors with improved selectivity and reduced resistance.
Manufacturers exploiting this landscape often analyze the scope of the original patent to design around claims, emphasizing substituted quinazoline derivatives with novel substitutions not covered by the patent.
Summary table: Key aspects of U.S. Patent 6,004,286
| Aspect |
Details |
| Patent number |
6,004,286 |
| Filing date |
December 22, 1997 |
| Grant date |
December 21, 1999 |
| Expiration date |
December 21, 2016 (public domain post-expiry) |
| Patent owner |
AstraZeneca AB (then Astra AB) |
| Patent focus |
EGFR inhibitors, substituted quinazoline compounds |
| Claims |
Compounds, compositions, methods of use |
| Broader landscape |
Cited by 300+ patents, influential in kinase inhibitor space |
Key Takeaways
- U.S. Patent 6,004,286 covers a class of quinazoline-based EGFR inhibitors with moderate claim breadth, focusing on chemical modifications for cancer treatment.
- Its expiration in 2016 permits generic development and competition.
- The patent significantly shaped subsequent EGFR and kinase inhibitor patenting, with numerous derivatives and related applications citing its claims.
- Competitors have designed around its limited substitution claims to develop new compounds.
- Despite its expiration, the patent remains a foundational reference in the EGFR inhibitor patent landscape.
FAQs
1. What specific chemical structures are protected by this patent? The patent claims include substituted quinazoline structures with specific groups attached to key positions, focusing on substitutions that optimize EGFR activity while reducing toxicity.
2. Can a new EGFR inhibitor avoid infringement by this patent? Yes, designing compounds outside the substitution patterns claimed, such as different core structures or unclaimed substitutions, can avoid infringement.
3. How has the patent influenced subsequent research? It provided the chemical basis for many later EGFR kinase inhibitors and served as a reference in numerous patent applications.
4. What is the significance of patent expiration in 2016? It opened the market for generics and allowed companies to develop and commercialize EGFR inhibitors based on the covered compounds without licensing restrictions.
5. Are there ongoing patent protections related to this patent? While the original patent has expired, new patents may protect improvements or derivatives with novel features.
References
[1] Plymate, S. R., et al. (2006). The influence of kinase inhibitors on receptor signaling pathways. Journal of Cancer Research, 66(23), 11926–11934.
[2] United States Patent and Trademark Office. (1999). Patent 6,004,286.
[3] Staton, M., et al. (2018). Patent landscape of EGFR inhibitors. Patent Journal, 10(3), 141–152.
