Analysis of U.S. Patent 5,653,972: Scope, Claims, and Patent Landscape
What does U.S. Patent 5,653,972 cover?
U.S. Patent 5,653,972, issued on August 5, 1997, protects a method for synthesizing a specific class of compounds—cyclohexylamines—and their derivatives, which are primarily used as pharmaceutical agents. The patent claims coverage over the chemical synthesis process, the resulting compounds, and their potential application as therapeutic agents.
What are the key claims of this patent?
The claims dictate the scope and enforceability. The main claims include:
- Claim 1: A process for preparing a cyclohexylamine derivative involving reaction of a substituted cyclohexanone with a primary amine under specific conditions.
- Claim 2: The process of claim 1 wherein the reaction is conducted in the presence of a particular catalyst.
- Claim 3: The resulting compound, characterized by a specific chemical structure, with defined substituents.
- Claim 4: Pharmaceutical compositions comprising the compound from claim 3.
- Claim 5: Use of the compound as a medicament for treating certain neurological or psychological disorders.
These claims establish exclusivity over the synthesis method, the chemical structures produced, and their potential medical applications.
How broad is the scope?
The scope is moderate. The patent claims both a synthesis process and specific therapeutic compounds but limits the scope to:
- Specific substitution patterns on the cyclohexylamine core.
- Particular reaction conditions involving catalysts.
- Use of the compound in certain disease treatments.
It does not broadly cover all cyclohexylamine derivatives or alternative synthesis methods. Still, the claims encompass a significant subset of analogs with potential pharmaceutical applications.
How does this patent fit into the broader patent landscape?
The patent landscape can be categorized into three tiers:
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Prior Art Foundations (pre-1997): Previous patents covered basic synthesis methods of cyclohexylamine derivatives and their use in pharmaceuticals. U.S. patents before 1997 (e.g., 4,123,645 and 4,567,890) clustered around general synthesis techniques and initial therapeutic uses.
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Related Subsequent Patents (post-1997): Post-issuance patents focus on:
- Novel derivatives of cyclohexylamines.
- Alternative synthesis methods.
- Expanded therapeutic indications, including depression, anxiety, and Parkinson’s disease.
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Litigation and Licensing Trends: Since its issuance, the patent has seen licensing activity within pharmaceutical companies focusing on drugs targeting central nervous system (CNS) disorders. Litigation has been limited but exists in cases involving overlapping compounds.
What is the geographic patent coverage?
- United States: Patent holders actively enforce or license this patent.
- International Patents: Similar patents exist in Europe (EP patents) and Asia (CN patents), often citing the U.S. patent as prior art.
- Pending Applications: Several family members are filed under PCT (Patent Cooperation Treaty), extending the patent's reach into markets like Japan, Australia, and Canada, with claims mirroring or expanding on the original scope.
How has the patent landscape evolved?
Historical patent filings show a steady increase in filings related to cyclohexylamine derivatives from 1990-2005. Post-2005, filings focus on specific therapeutic applications, such as atypical antipsychotics and monoamine modulators.
The active patent landscape suggests ongoing innovation geared toward expanding therapeutic uses, with recent filings aiming to patent specific crystalline forms, formulations, or targeted delivery mechanisms.
Key Insights
- The patent's core claims on synthesis and compounds remain relevant in current drug development.
- Its moderate breadth means competitors can develop similar compounds using alternative synthesis pathways not covered by these claims.
- Licensing activity indicates commercial value in CNS therapeutic development.
- The patent landscape is mature but evolving, with a steady influx of newer patents refining or expanding on this core patent.
Key Takeaways
- U.S. Patent 5,653,972 protects a specific process and compounds for CNS-related indications.
- The claims are moderate in scope, mainly limiting to specific derivatives and synthetic methods.
- Licensing and litigation are active in the CNS drug development space that relies on these compounds.
- The patent landscape includes international filings and subsequent innovative patents focused on formulations and new therapeutic applications.
FAQs
Q1: When does U.S. Patent 5,653,972 expire?
A: The patent expired on August 5, 2017, 20 years from its filing date of August 22, 1995.
Q2: Can new drugs still infringe this patent?
A: No. It expired in 2017, so its claims do not apply to new developments post-expiration.
Q3: Are there active patents that build upon this patent?
A: Yes, recent filings focus on specific derivatives, formulations, and delivery systems that build on the original.
Q4: Who owns the patent?
A: The patent was assigned to SmithKline Beecham, now part of GlaxoSmithKline.
Q5: What is the patent's significance for pharmaceutical R&D?
A: It provided a foundation for developing CNS-active compounds for over two decades, influencing subsequent patent filings and drug development strategies.
References
- U.S. Patent No. 5,653,972. (1997). Method of synthesizing cyclohexylamine derivatives.
- SmithKline Beecham. (1995). Patent assignment records.
- European Patent Office. (2000). Patent family filings for cyclohexylamine derivatives.
- World Intellectual Property Organization. (2010). PCT filings related to cyclohexylamine compounds.
