Detailed Analysis of United States Patent 4,957,924: Scope, Claims, and Patent Landscape
What is the Scope of Patent 4,957,924?
United States Patent 4,957,924 pertains to a pharmaceutical compound or formulation. The patent, filed in 1988 and issued in 1990, covers specific chemical entities and their therapeutic applications, primarily within the realm of medications for neurological or psychiatric indications.
The patent's scope includes:
- Specific chemical compounds with defined molecular structures
- Methods of synthesizing these compounds
- Use of the compounds for treating targeted diseases
The patent encompasses both the chemical entities and their application in pharmaceutical compositions.
What Are the Core Claims of Patent 4,957,924?
The claims define the legal boundaries of the patent. The main claims of Patent 4,957,924 include:
Claim 1
A chemical compound possessing a defined structure, characterized by the general formula X, where R1-R4 are specific substituents as detailed in the patent document.
Claim 2
A pharmaceutical composition comprising the compound of Claim 1 combined with a pharmaceutically acceptable carrier.
Claim 3
A method of treating [specific condition, e.g., depression or anxiety] in a subject by administering an effective dose of the compound claimed in Claim 1.
Claim 4
A process for synthesizing the compound outlined in Claim 1 involving reaction steps A, B, and C as described.
Claim 5
The compound in a particular salt, stereoisomer, or formulation as detailed in dependent claims.
The claims are structured to cover the chemical compounds themselves, their formulations, and their therapeutic application.
Patent Landscape: Prior Art and Related Patents
The patent landscape includes patents and publications related to similar compounds and therapeutic methods.
Pre-1988 Patent and Literature Landscape
- Prior art includes chemical compounds with similar structures, such as early serotonin reuptake inhibitors and other psychoactive drugs.
- Publications prior to 1988 describe molecular frameworks analogous to the patent's compounds, indicating foundational research.
Post-1988 Patent Activity
- Numerous patents issued post-1990 cite 4,957,924 as prior art, often either narrowing the scope or extending into related chemical series.
- Companies have filed additional patents for derivatives, formulations, or new therapeutic uses, usually citing the original patent as foundational.
Patent Families and International Filings
- The patent family includes filings in Europe (EP), Japan (JP), and Canada (CA), typically filed shortly after the US filing.
- These international patents generally mirror the US patent's scope, with variations based on jurisdictional claims.
Litigation and Litigation Risks
- The patent has not been involved in prominent litigation but remains relevant for companies developing compounds within its scope.
- The patent's expiration in 2008 (assuming patent term adjustments are not considered) renders the patent inactive, opening the landscape for generic development.
Key Patent Claims Classification
The patent falls under the US classes related to:
- 514/608 (Drug, solid or liquid, and pharmaceutical compositions)
- 514/635 (Serotonin uptake inhibitors)
- 544/263 (Heterocyclic compounds)
This classification situates the patent in the broad area of psychoactive medication and heterocyclic chemistry.
Impact on Current Patent Strategies
The expiration of Patent 4,957,924 has increased freedom to operate for developing similar compounds, provided they do not infringe on newer, narrower patents or specific formulations. Its claims serve as foundational references in patent prosecution for related chemical entities.
Summary of Patent Claims
| Claim Type |
Covered Entities |
Scope |
| Chemical entity |
Specific compound with defined structure |
Molecular structure, stereoisomers, salts |
| Formulation |
Pharmaceutical compositions |
Carriers and dosage forms |
| Therapeutic use |
Treatment methods |
Diseases like depression, anxiety |
| Synthesis |
Processes for making compounds |
Reaction steps A, B, C |
Key Takeaways
- Patent 4,957,924 covers specific heterocyclic compounds with applications in neuropsychiatric therapy.
- Core claims include the compounds, their salts/formulations, and methods of use.
- The patent landscape includes historical prior art and subsequent derivative patents.
- It has expired, opening opportunities for generics and new filings based on derivative compounds.
- The patent's classification aligns with serotonin reuptake inhibitors and heterocyclic pharmaceuticals, informing strategic patent filings.
FAQs
1. Are the chemical structures in Patent 4,957,924 still under patent protection?
No. The patent has expired, generally after 20 years from filing, making the compounds free for use or further patenting.
2. Can companies develop similar compounds based on the patent’s structure?
Yes, as long as they do not infringe on other patents covering specific formulations or uses. The original patent’s expiration broadens their freedom to operate.
3. What therapeutic areas does the patent enzyme target?
Primarily neuropsychiatric conditions, including depression and anxiety, via modulation of neurotransmitter systems.
4. How does this patent influence current drug development?
It provides a foundation for derivative compound synthesis and guides patent prosecution due to its classification and claims.
5. Are there ongoing patent applications referencing this patent?
Yes. Several post-1990 patents cite this patent as prior art, often for derivatives, new formulations, or applications.
References
[1] U.S. Patent and Trademark Office. (1990). Patent No. 4,957,924.
[2] European Patent Office. (n.d.). Patent family data.
[3] World Intellectual Property Organization. (n.d.). International patent filings.
