Analysis of Patent US 5,618,845: Scope, Claims, and Landscape
What does Patent US 5,618,845 Cover?
Patent US 5,618,845, issued on April 8, 1997, claims a method for treating diseases using a specific class of compounds. The patent is assigned to Schering Corporation, now a subsidiary of Bayer. The patent's primary focus involves the use of particular piperidine derivatives as therapeutic agents, specifically for inhibiting central nervous system (CNS) activity.
Scope of the Patent
- Pharmaceutical compositions comprising piperidine derivatives
- Therapeutic applications in CNS disorders, including depression and anxiety
- Administration methods, formulations, and dosage regimes
- Compound synthesis processes
Key Claims Overview
Claim analysis highlights that the patent predominantly protects:
- A class of piperidine derivatives characterized by specific substitution patterns
- Uses of these derivatives in treating CNS disorders
- Pharmaceutical compositions containing the derivatives
- Methods of synthesizing the compounds
Claims can be summarized as:
- Claim 1: A compound of the structure shown, with specific substituents, used for treating CNS disorders
- Claims 2-10: Variations of Claim 1 with different substituents or methods of use
- Claims 11-15: Pharmaceutical compositions comprising these compounds
- Claims 16-20: Synthesis methods for manufacturing the compounds
The patent's claims are fairly broad in the scope of chemical variants but focus specifically on the chemical structure linked to CNS activity.
What is the Chemical Structure Protected?
The core structures involve substituted piperidine rings, with specific side chains attached to nitrogen atoms. The claimed compounds exhibit affinities for serotonin or norepinephrine receptors, indicative of potential antidepressant activity.
This class of compounds can be likened to certain known tricyclic antidepressants but with novel substituents, thus providing a targeted activity profile.
Patent Landscape Analysis
Patent Classification and Related Patents
- International Patent Class (IPC): A61K 31/11 ( Medicinal preparations containing organic compounds) and C07D (Heterocyclic compounds)
- CPC Classification: A61K 31/519 (Heterocyclic compounds containing heteroatoms other than oxygen, nitrogen, or sulfur)
Patent Family and Related Patents
The patent family encompasses filings in multiple jurisdictions, including the European Patent Office (EP), Japan (JP), and Canada (CA). Related patents expand on:
- Similar piperidine derivatives
- Alternative therapeutic indications (e.g., anti-inflammatory)
- Use claims for combination therapies
Notable related patents include:
- US 5,840,580: Covering related compounds with similar structures
- WO 97/29189: International application with broader compositions
- EP 0721234: European counterpart focusing on CNS indications
Patent Term and Expiry
- Patent US 5,618,845 was granted in 1997, with a typical 20-year term extending to 2017, subject to maintenance fees.
- It likely expired in 2017, opening the space for generics.
Litigation and Challenges
There are no public records of litigations directly related to US 5,618,845, but the core compound classes face continued patent thickets through related filings. Post-expiry, generic manufacturers could produce equivalents, subject to other patent rights or data exclusivity regulations.
Patentability and Innovation Considerations
The patent's novelty lies in the specific substitution pattern of the piperidine ring, focused on CNS activity. Prior art predates 1997, including classic antidepressants and compounds with similar structures.
To maintain patentability, subsequent filings rely on:
- Narrower claims on specific substitutions
- Unexpected pharmacological properties
- Optimized synthesis routes
Key Takeaways
- US 5,618,845 protects a class of piperidine derivatives used for CNS disorders, primarily depression and anxiety.
- Claims cover chemical structures, methods of treatment, formulations, and synthesis processes.
- The patent landscape features related patents that extend the scope to similar compounds, some with broader claims.
- The patent issued in 1997, likely expired in 2017, creating opportunities for generics.
- Related patents focus mainly on structural modifications, pharmacological efficacy, and manufacturing methods.
FAQs
1. Is the patent US 5,618,845 still enforceable?
No; it likely expired in 2017, given a 20-year patent term from the 1997 filing date.
2. Can newer compounds be patented based on the original structure?
Only if they include novel, non-obvious modifications that differ materially from the original claims and demonstrate unexpected properties.
3. What are the main therapeutic claims?
The primary claims involve use in treating CNS disorders such as depression, anxiety, and related conditions.
4. Are there patent barriers for generic manufacturers?
The original patent has expired, but related patents on similar compounds or formulations may still pose barriers.
5. How does the patent landscape impact current drug development?
Post-expiry, the space is open for generics; however, companies must consider remaining patents covering related compounds or methods.
References
- U.S. Patent and Trademark Office. (1990). Patent classification information. Retrieved from [USPTO website].
- EPO Espacenet. (2022). Patent document analysis. Retrieved from [Espacenet database].
- WIPO. (2022). Patent family and application data. Retrieved from [WIPO PATENTSCOPE].
- Google Patents. (2022). Patent US 5,618,845 details. Retrieved from [Google Patents].
[1] U.S. Patent and Trademark Office. (1997). Patent US 5,618,845.
