United States Patent 4,604,463: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 4,604,463, granted on August 5, 1986, is a significant patent in the field of pharmaceuticals, particularly concerning camptothecin derivatives. This patent, assigned to the inventors Miyasaka et al., has had a profound impact on the development of cancer therapies. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background
Camptothecin is a naturally occurring compound with potent anticancer properties. However, its clinical use was initially limited due to its poor solubility and stability. The invention described in U.S. Patent 4,604,463 addresses these issues by providing methods for preparing camptothecin derivatives, such as irinotecan, which are more stable and effective.
Scope of the Patent
The patent covers the preparation and use of various camptothecin derivatives. Here are the key aspects of its scope:
Chemical Compounds
The patent describes several camptothecin derivatives, including those with modifications at the 10-hydroxy position. These derivatives are designed to improve the pharmacological properties of camptothecin, such as its solubility, stability, and bioavailability[5].
Synthesis Methods
The invention includes detailed methods for synthesizing these derivatives. For example, it describes the use of specific solvents and catalysts to achieve selective oxidation and hydrogenation reactions, which are crucial for producing the desired compounds without unwanted by-products[4].
Pharmaceutical Applications
The patent emphasizes the pharmaceutical applications of these derivatives, particularly in cancer treatment. It outlines how these compounds can be formulated into pharmaceutical compositions suitable for administration to patients.
Claims of the Patent
The claims of U.S. Patent 4,604,463 are comprehensive and cover various aspects of the invention:
Compound Claims
The patent claims specific camptothecin derivatives, including their structures and methods of preparation. For instance, it claims irinotecan and its pharmaceutically acceptable salts[5].
Method Claims
The claims include methods for preparing these derivatives, such as the steps involved in the synthesis process, including the use of specific reagents and conditions[4].
Use Claims
The patent also claims the use of these derivatives in the treatment of cancer. It specifies the therapeutic applications and the dosages of the compounds.
Patent Landscape
Understanding the patent landscape around U.S. Patent 4,604,463 is crucial for assessing its impact and the competitive environment.
Prior Art
The patent builds upon earlier research in camptothecin chemistry. Prior art includes patents and publications that described the initial isolation and basic chemistry of camptothecin. However, the '463 patent introduces significant improvements in the synthesis and stability of these compounds[5].
Subsequent Patents
Several subsequent patents have built upon the foundation laid by U.S. Patent 4,604,463. These include patents for further modifications of camptothecin derivatives, new synthesis methods, and additional therapeutic applications. For example, patents like U.S. Pat. No. 5,693,761 and U.S. Pat. No. 6,124,551 describe additional camptothecin derivatives and their uses[1].
Competitive Environment
The patent landscape in the field of camptothecin derivatives is highly competitive. Multiple pharmaceutical companies have developed their own versions of these compounds, each with their own set of patents. This competition has driven innovation, leading to more effective and safer cancer treatments.
Impact on the Pharmaceutical Industry
U.S. Patent 4,604,463 has had a significant impact on the pharmaceutical industry, particularly in the development of cancer therapies.
Clinical Use
The camptothecin derivatives described in the patent, such as irinotecan, have been widely used in clinical settings for treating various types of cancer, including colorectal cancer.
Research and Development
The patent has spurred further research into camptothecin chemistry, leading to the development of new drugs and therapeutic strategies. It has also influenced the design of new anticancer agents based on similar chemical structures.
Patent Analytics and Claim Coverage
To fully understand the protection and opportunities provided by U.S. Patent 4,604,463, patent analytics tools are essential.
Claim Coverage Matrix
A Claim Coverage Matrix can help identify which patents and claims are actively protecting the intellectual property related to camptothecin derivatives. This tool categorizes patents by claims and scope concepts, making it easier to analyze large numbers of patent claims concurrently[3].
Claim Charts
Interactive claim charts generated by tools like ClaimScape® software can be reviewed by technical experts to determine the applicability of specific scope concepts to target products or methods. This helps in identifying gaps in current coverage and highlighting future design opportunities[3].
Regulatory Considerations
Patents like U.S. Patent 4,604,463 often involve regulatory reviews that can impact their term and scope.
Patent Term Extension
Under 35 U.S.C. 156, patents that claim products or methods subject to regulatory reviews by the FDA or USDA can be extended for up to five years. This provision has been applied to various pharmaceutical patents, potentially affecting the term of U.S. Patent 4,604,463 if it had been subject to such reviews[2].
Key Takeaways
- Innovative Synthesis Methods: U.S. Patent 4,604,463 introduced improved methods for synthesizing camptothecin derivatives, enhancing their stability and pharmacological properties.
- Broad Therapeutic Applications: The patent covers the use of these derivatives in cancer treatment, contributing significantly to the development of anticancer therapies.
- Competitive Patent Landscape: The patent is part of a highly competitive landscape, with numerous subsequent patents building upon its innovations.
- Regulatory Implications: The patent's term and scope could be influenced by regulatory reviews and extensions under U.S. patent law.
Frequently Asked Questions (FAQs)
What is the main subject of U.S. Patent 4,604,463?
U.S. Patent 4,604,463 primarily deals with the preparation and use of camptothecin derivatives, particularly those with improved stability and pharmacological properties.
Who are the inventors of U.S. Patent 4,604,463?
The inventors of U.S. Patent 4,604,463 are Miyasaka et al.
What are some of the key camptothecin derivatives described in the patent?
The patent describes several camptothecin derivatives, including irinotecan and its pharmaceutically acceptable salts.
How has U.S. Patent 4,604,463 impacted the pharmaceutical industry?
The patent has significantly contributed to the development of cancer therapies by providing methods for synthesizing stable and effective camptothecin derivatives.
Can the term of U.S. Patent 4,604,463 be extended under U.S. patent law?
Yes, if the patent claims a product or method subject to regulatory reviews by the FDA or USDA, its term could be extended under 35 U.S.C. 156.
Cited Sources:
- United States Patent and Trademark Office, "US10308719B2," June 4, 2019.
- United States Patent and Trademark Office, "Extension Under 35 U.S.C. 156(e)(1) - OG Date: 29 July 2003."
- SLWIP, "Patent Analytics | Intellectual Property Law."
- Google Patents, "US5734056A - Process for the preparation of certain 9-substituted camptothecins."
- Justia Patents, "7910737 - Process for the manufacturing of 7-ethyl-10-hydroxy camptothecin."
