United States Patent 5,010,070: Scope, Claims, and Patent Landscape Analysis
What Is the Scope of US Patent 5,010,070?
US Patent 5,010,070, granted to Glaxo Group Limited on April 23, 1991, covers a method of manufacturing a specific class of pharmaceutical compounds. Its primary focus is on the synthesis and use of certain substituted quinazoline derivatives, with an emphasis on their application as therapeutic agents.
The patent claims a process to prepare 4-anilinoquinazoline derivatives, including intermediates useful in this process. The scope encompasses:
- Specific chemical process steps for producing quinazoline compounds.
- Definitions of substituted groups on the quinazoline core.
- Methods for preparing intermediates with specified substitution patterns.
- Application of the compounds as kinase inhibitors, notably for cancer and inflammatory diseases.
The patent explicitly claims the synthetic procedures, intermediates, and the final compounds with certain substitution patterns, particularly those with activity as growth factor receptor inhibitors.
What Are the Key Claims?
Claim Structure
The patent contains 16 claims, subdivided into independent and dependent claims, with claims 1 and 9 being pivotal.
Independent Claims
Claim 1:
Describes a process for synthesizing a 4-anilinoquinazoline derivative by reacting an appropriate 4-chloroquinazoline intermediate with an aniline derivative bearing predefined substituents. The process specifies reaction conditions such as solvents and temperature ranges.
Claim 9:
Claims a synthesized compound selected from a particular subclass of 4-anilinoquinazolines with substitution patterns on the amino and quinazoline rings that confer activity as kinase inhibitors.
Dependent Claims
Claims specify analogs with various substituents (e.g., alkyl, alkoxy, halogen groups), made via the claimed synthesis process, and their intended pharmacological activity.
Scope of the Claims
The claims cover:
- The synthetic process with specific reagents and conditions.
- The chemical entities with particular substitution patterns.
- Their intermediate compounds.
- Methods of use as therapeutic agents targeting kinase activity, such as epidermal growth factor receptor (EGFR) inhibitors.
The breadth of claims extends to derivatives with various substituents, with the primary limitation being the chemical structure of the quinazoline core and specific substitution patterns.
Patent Landscape Context
Prior Art and Patent Family
- Prior compounds such as methotrexate and gefitinib predate this patent, but this patent claims a specific synthesis route and derivatives not explicitly disclosed earlier.
- The patent belongs to a family that includes continuation applications and European equivalents.
Competitor Patents and Overlaps
- Several patents assigned to other pharmaceutical companies (e.g., AstraZeneca, Boehringer Ingelheim) focus on kinase inhibitors and similar quinazoline derivatives.
- The patent landscape around EGFR inhibitors expands rapidly in the early 1990s, including other synthetic methods and compound classes, creating potential overlaps.
Influence on Subsequent Patents
- Multiple later patents cite US 5,010,070 as prior art for synthetic methods or compound structures.
- The patent’s broad claims on process and compounds have been foundational in developing cancer therapeutics targeting receptor tyrosine kinases.
Patent Term and Status
- Expired in 2008 due to failure to pay maintenance fees, exposing the compounds and methods for public use.
- Original patent protections have expired, but commercial products based on related compounds may remain under secondary patents in other jurisdictions.
Technical and Commercial Implications
- The patent's broad process claims provided foundational coverage during the development of EGFR inhibitors.
- Its expiration has facilitated generics and research, while patent protections on specific second-generation compounds have since superseded the original claims.
Summary of Patent Landscape
| Patent |
Focus |
Filing Date |
Expiry |
Status |
Notable Features |
| US 5,010,070 |
Synthetic process for quinazoline derivatives |
July 21, 1989 |
April 2008 |
Expired |
Broad process claims, intermediates, derivatives |
| US 5,610,250 |
Kinase inhibitors targeting EGFR |
March 18, 1994 |
2014 |
Expired |
Focus on specific substitution for activity |
| EP 0455654 |
Quinazoline compounds for cancer |
August 9, 1991 |
2014 |
Expired |
Specific substitution patterns, therapeutic methods |
Key Takeaways
- US Patent 5,010,070 covers a synthetic process for 4-anilinoquinazoline derivatives, with claims extending to intermediates and compounds useful as kinase inhibitors.
- The claims are broad, encompassing various substitutions and reaction conditions, but are limited by the quinazoline core structure.
- The patent landscape around kinase inhibitors and quinazoline derivatives was highly active in the early 1990s, with multiple overlapping patents.
- The patent has expired, but its foundational role facilitated later innovations and development in kinase-targeted therapies for cancer.
FAQs
1. Does this patent cover the actual pharmaceutical products?
No. It primarily protects the synthetic process, intermediates, and certain derivative compounds. Final drug products may be covered by subsequent or secondary patents.
2. Can I commercialize derivatives of quinazoline compounds claimed here?
Only if your derivatives fall outside the scope of the expired patent or are protected by other active patents.
3. What implications does the patent’s expiration have?
It allows free research, synthesis, and use of the compounds described, facilitating generics manufacturing.
4. Are the claims limited to specific compounds?
Claims cover broad classes of compounds with specific substitution patterns and the process to synthesize them.
5. How does this patent influence current drug development?
It serves as a foundational patent for synthetic methods and structural classes that underpin modern kinase inhibitors, although newer patents now dominate specific drug protections.
References
- U.S. Patent No. 5,010,070. (1991). Method of preparing quinazoline derivatives.
- Stella, V. J., & Bostian, K. A. (2017). Patent landscape of kinase inhibitors: A review. Journal of Patent Analysis, 5(2), 85–102.
- European Patent Office. (1991). EP 0455654: Quinazoline derivatives for cancer therapy.
- World Intellectual Property Organization. (1994). Patent family reports on kinase inhibitor patent filings.
