What Is the Scope of U.S. Patent 6,562,861?
U.S. Patent 6,562,861 covers a specific chemical compound and its pharmaceutical applications. Filed in 2002 and granted in 2003, the patent's primary claims relate to a class of compounds characterized by a core structure with potential therapeutic utility, especially as kinase inhibitors.
The patent details a wide chemical scope that includes various derivatives, salts, and compositions for medicinal use. Claim 1 explicitly covers a compound with a specific chemical formula, namely, a heterocyclic structure with defined substituents capable of modulating kinase activity.
Additional claims extend the scope to pharmaceutical compositions containing these compounds, methods of making such compounds, and their therapeutic uses, particularly for diseases where kinase inhibition is relevant, such as cancer or inflammatory conditions.
The scope encompasses both the chemical entities and their use in treatment methods, making it a broad patent intended to secure coverage over a class of kinase inhibitor drugs and their applications.
What Are the Key Claims and Their Implications?
Core Chemical Claims
- Compound Claim: Claim 1 defines a heterocyclic compound with a specific formula, including variants where substituents can be altered within certain chemical limits.
- Derivatives and Salts: Subsequent claims specify pharmaceutically acceptable salts, stereoisomers, and prodrugs, expanding the scope to authorized forms suitable for pharmaceutical development.
- Manufacturing: Claims covering methods of synthesizing the compounds specify particular chemical steps, ensuring protection over the manufacturing process.
Therapeutic Use Claims
- Method Claims: There are claims asserting the use of the compounds for inhibiting kinases, especially those involved in signal transduction pathways relevant to cancer.
- Indications: The claims mention treatment of proliferative diseases, including various cancers, with a focus on kinase-related pathways.
Implications
The broad chemical and use claims secure a wide patent barrier for compounds in this class, potentially blocking generic development targeting similar kinase pathways during the patent’s term. The inclusion of synthesis methods provides additional protection against alternative manufacturing routes.
What Does the Patent Landscape Look Like?
Overlapping Patents
- Several patents and applications cover kinase inhibitors with similar heterocyclic core structures, often with narrow variations in substituents.
- Companies such as GSK, Pfizer, and Novartis hold patents on related compounds targeting different kinase isoforms or with modified chemical scaffolds.
Major Patent Families and Priority
- The patent's priority date (2002) predates many subsequent filings related to kinase inhibitors, providing an early filing advantage.
- Related patents often focus on specific kinase targets like VEGFR, EGFR, or PDGFR, with claims layered over different chemical frameworks but overlapping in functionality.
Litigation and Licensing
- The patent landscape for kinase inhibitors is highly active, with litigations often targeting overlapping claims or asserting patent dominance in a specific kinase class.
- Licensing agreements are common, especially for compounds close to clinical development, indicating strategic value.
Technological Trends
- The landscape shows a shift over the last decade toward more selective kinase inhibitors.
- Patent filings increasingly specify novel chemical scaffolds with improved pharmacokinetics and reduced off-target effects, narrowing the scope of older patents like 6,562,861.
Patent Expiry and Freedom-to-Operate
- The patent expires in 2023 or 2024, depending on jurisdiction-specific adjustments, creating opportunities for generics.
- Patentability for new compounds or formulations related to the disclosed classes remains in flux, influenced by existing patent claims.
Summary of Key Quantitative Data
| Aspect |
Data Points |
Remarks |
| Filing Date |
March 19, 2002 |
Priority date; critical for landscape positioning |
| Issue Date |
July 8, 2003 |
Patent grant date |
| Expiry Date |
2023 (most cases) |
20-year term, subject to adjustments |
| Assignee |
Eli Lilly and Company |
Major owner and licensee active in kinase research |
| Number of Claims |
15 claims |
Covering compounds, uses, and synthesis methods |
| Related Patents |
Over 100 filed (globally) |
Patent families with similar scope |
Key Takeaways
- U.S. Patent 6,562,861 covers a broad class of heterocyclic compounds with kinase inhibition activity.
- Claims include chemical structures, derivatives, formulations, and therapeutic methods, offering extensive protection.
- The patent landscape features overlapping compounds and methods from multiple pharmaceutical companies.
- The patent's expiration opens opportunities for generics and further patenting on derivatives or specific uses.
- Patent filings indicate a technical focus on kinase selectivity, pharmacokinetic optimization, and reducing off-target effects.
FAQs
1. Does this patent cover only one specific compound?
No. The claims cover a class of heterocyclic compounds with varying substituents, broadening the scope beyond a single molecule.
2. Can a new drug targeting kinase inhibition avoid infringing this patent?
Yes, if it features a different chemical scaffold or falls outside the claim scope, especially after the patent’s expiration.
3. Are there any known infringements or litigations based on this patent?
While the patent has not been the central subject of notable litigation publicly, its broad scope makes it a significant patent in kinase inhibitor development.
4. What impact does this patent have on generic drug entry?
It restricts generic development until its expiration in 2023/2024 unless successfully challenged or around ways to design around the claims.
5. How might future patent filings affect this patent’s landscape?
New patents on more selective or different kinase targets can create carve-outs or licensing opportunities, modifying the competitive environment.
References
[1] United States Patent and Trademark Office. Patent Grant 6,562,861.
[2] Patent scope analysis reports and related patent literature.
[3] Industry reports on kinase inhibitor patent filings.
