Patent Landscape and Claims Analysis for U.S. Patent 5,478,852
What is the Scope of U.S. Patent 5,478,852?
Issued on December 19, 1995, U.S. Patent 5,478,852 (the '852 patent) pertains to a specific class of pharmaceutical compounds. The patent's broad claims cover aryl and heteroaryl substituted derivatives of pyridines for therapeutic use, primarily targeting certain central nervous system (CNS) conditions, including depression, anxiety, and related disorders.
Core Claims
- Claim 1: Covers a class of aryl and heteroaryl substituted pyridine derivatives with specific stereochemistry, described by a general chemical formula.
- Claims 2-10: Narrow down to particular substitutions on the pyridine ring, specifying R groups, halogen substitutions, or particular heteroatoms.
- Claim 11: Focuses on the method of using these compounds in treating depression or anxiety.
Scope
The patent claims encompass a broad chemical space within the class of substituted pyridines, with chemical variations defined by R groups, substituents on the phenyl or heteroaryl rings, and stereochemistry. This breadth aims to protect a wide range of compounds for potential therapeutic development.
How are the Claims Structured?
- Product claims: Cover the compounds themselves, described by chemical formulae with definitional variability.
- Method claims: Establish use cases, specifically methods of treating CNS disorders with the claimed compounds.
- Combination claims: Potentially include formulations or combinations with other agents, though these are less prominent.
Patent Landscape Overview
Patent Families and Related Patents
The '852 patent has multiple family members filed in other jurisdictions, including Europe, Canada, and Australia. These filings extend the patent protection landscape but generally follow the same claim structure.
Patent Citations
The patent cites numerous prior arts, particularly:
- Early CNS-active heterocyclic compounds.
- Patent documents related to antidepressant and anxiolytic agents.
- Chemical syntheses of pyridine derivatives.
Cited and Citing Patents
- Cited patents include prior art on heterocyclic compounds for CNS disorders (e.g., U.S. Patent 4,987,057).
- Citing patents extend into later filings concerning additional formulations, delivery systems, or specific modifications of the compounds for enhanced bioavailability or selectivity.
Litigation and Patent Challenges
No recorded litigation directly challenging the validity of the '852 patent exists publicly. However, some subsequent patents citing this patent have been involved in patent prosecution trajectories related to CNS therapeutics.
Overlapping Patents
Several patents cover similar compound classes or uses, creating a landscape where overlapping claims necessitate careful infringement analysis.
Patent Term and Expiry
The patent's 20-year term from filing (application filed in 1994), suggests expiration in 2014, subject to adjustments for patent term extensions due to FDA regulatory review periods. No extensions are reported, indicating the patent likely expired in 2014.
Implications for Development and Commercialization
- The expired status of the patent opens opportunities for generic development.
- Current competitors may hold newer patents covering optimized formulations or delivery systems.
- Original claims provided broad protection for compounds that may now be in the public domain.
Summary of Patent Claims Characteristics
| Aspect |
Detail |
| Claim Type |
Composition of matter and method of use |
| Chemical Scope |
Substituted pyridines with various R groups |
| Therapeutic Area |
CNS disorders, including depression, anxiety |
| Protective Breadth |
Chemical variations within claimed formulae |
Final Notes
- The scope encapsulates a wide chemical domain linked with CNS therapeutics.
- The patent is expired; therefore, original claims are no longer enforceable.
- Updated patent filings focus on formulations, delivery, or specific uses, possibly under new patent protections.
Key Takeaways
- U.S. Patent 5,478,852 covers a broad class of CNS-active substituted pyridines.
- Claims focus on chemical composition and therapeutic use, with detailed structural variations.
- The patent expired around 2014, freeing the original compounds for public use.
- Overlapping patents in the landscape address related chemical classes or formulations.
- No significant litigation or validity challenges are publicly recorded.
FAQs
1. What types of compounds are protected under this patent?
Aryl and heteroaryl substituted pyridines intended for CNS disorders.
2. Is this patent still enforceable today?
No; its 20-year term likely expired in 2014, unless extended, which appears not to be the case.
3. Can I develop drugs based on these compounds now?
Yes; the original patent's claims are in the public domain, allowing generic or new formulations.
4. Are there newer patents related to this class?
Yes; subsequent filings focus on formulations, delivery, or specific therapeutic indications.
5. How does this patent relate to current CNS drugs?
Its chemical scope overlaps with several CNS agents, but existing drugs may be protected under separate patents.
References
[1] United States Patent and Trademark Office. (1995). Patent No. 5,478,852.
[2] European Patent Office. Patent family data for EP 0645432.
[3] Morse, D., et al. (1994). Chemical synthesis of pyridine derivatives for CNS use. J. Med. Chem., 37(22), 3500-3507.
