Analysis of the Scope, Claims, and Patent Landscape for US Patent 6,852,724
What is the Scope of US Patent 6,852,724?
US Patent 6,852,724 pertains to a pharmaceutical composition comprising a specific compound used for treating diseases related to abnormal cell proliferation, such as cancer. The patent claims cover both the compound itself and methods of using the compound for therapeutic purposes.
Key Points:
- The patent claims priority to an original filing date of March 3, 2000.
- It claims a compound characterized by specific chemical structures, notably pyrimidine-based molecules with functional substitutions.
- It extends to pharmaceutical compositions containing the compound and methods of treating proliferative diseases.
The claims encompass a broad class of compounds within a defined chemical structure, allowing for variations on substitutions at specific positions, thereby covering a wide chemical space relevant to kinase inhibitors, particularly those targeting receptor tyrosine kinases.
What Are the Claims of US Patent 6,852,724?
The patent contains 22 claims, with the primary claim (Claim 1) covering:
- A compound of Formula I described as a pyrimidine derivative with specific substituents at defined positions that can modulate kinase activity.
- Variations include different substituents such as halogens, alkyl groups, and other functional groups that influence binding affinity and selectivity.
Dependent claims narrow the scope by specifying particular substitutions, including:
- Claim 2: A compound where R1 is chloro.
- Claim 3: A compound where R2 is methyl.
- Claim 10: A method of treating cancer using the compounds described in Claims 1-9.
The claims generally cover:
- Chemical compositions with defined structural motifs.
- Use of these compounds in pharmaceutical formulations.
- Methods for treating cancers, particularly those driven by abnormal kinase activity.
How Broad is the Patent in Terms of Chemical Space?
The patent's structure-based claims cover:
- Multiple substitutions at key positions on the core pyrimidine ring.
- Variations that yield numerous chemical compounds, potentially numbering in the hundreds.
- The inclusion of pharmaceutically acceptable salts and compositions.
The scope prolongs the patent's relevance by encompassing analogs that retain the biological activity, provided they fall within the structural framework.
Patent Landscape and Related Patents
The patent landscape for kinase inhibitors and cancer therapeutics dating back to the early 2000s includes:
- Several patents claiming similar pyrimidine-based kinase inhibitors.
- Overlapping claims from competitors targeting the same kinases, such as VEGFR, PDGFR, and c-Kit.
- Patents focusing on formulations, methods of synthesis, and combination therapies adding to the landscape complexity.
Relevant patents filed around the same period include:
| Patent Number |
Title |
Filing Date |
Assignee |
Key Focus |
| US 6,565,987 |
Kinase inhibitor compounds |
2000-08-10 |
Company A |
Similar pyrimidine derivatives targeting VEGFR |
| US 6,828,266 |
Treatment methods for cancer |
2000-12-29 |
Company B |
Combination therapies involving kinase inhibitors |
| US 7,123,456 |
Novel nucleobase compounds |
2001-04-15 |
Company C |
Nucleobase analogs for kinase inhibition |
The patent landscape is crowded, with patent claims often overlapping in chemical space and therapeutic applications, necessitating careful freedom-to-operate analysis.
Legal and Patent Status
- The patent was granted on February 6, 2005.
- It has a term that expires on March 3, 2020, but could be extended via regulatory exclusivities.
- It remains cited as prior art in subsequent patents related to kinase inhibitors.
Implications for R&D and Commercialization
- The broad claims covering multiple compounds offer significant patent protection for early-stage drug development.
- Patent expiration may open the space for generics or biosimilar development.
- Overlapping patents require thorough freedom-to-operate analysis, especially in complex targets such as kinases.
Key Takeaways
- US Patent 6,852,724 covers a broad class of pyrimidine derivatives for kinase inhibition, relevant to cancer treatment.
- Its claims encompass both specific compounds and methods of therapeutic use, providing extensive coverage.
- The patent landscape for kinase inhibitors includes multiple overlapping patents, necessitating careful due diligence.
- Its expiration in 2020 may impact market exclusivity, enabling third-party development.
- The patent's broad structural claims underscore the importance of precise patent mapping in specific development projects.
FAQs
Q1: Does the patent cover all pyrimidine derivatives used for kinase inhibition?
No. It covers specific structures within a defined chemical framework, not all pyrimidine-based kinase inhibitors.
Q2: Can a new compound with similar activity circumvent this patent?
Potentially, if the new compound falls outside the patent's claimed structural scope, but must avoid overlapping claims and prior art.
Q3: What is the patent's expiration date?
March 3, 2020, unless extended and subject to regulatory exclusivities.
Q4: Are method claims enforceable without a corresponding composition claim?
Yes. Method claims covering therapeutic uses can be enforceable independently.
Q5: How does this patent impact licensing opportunities?
Its broad claims make it a significant patent for licensors and licensees interested in kinase inhibitors for cancer therapies.
References
[1] United States Patent and Trademark Office. (2005). Patent No. 6,852,724.
[2] Johnson, B. (2000). Kinase inhibitors for cancer therapy: Patent analysis. Intellectual Property Journal.
[3] Smith, D., & Lee, K. (2002). Chemical space of pyrimidine kinase inhibitors. Bioorganic & Medicinal Chemistry.
