Scope and Claims Analysis of U.S. Patent 6,133,251
What is the Scope of U.S. Patent 6,133,251?
U.S. Patent 6,133,251, granted on October 17, 2000, covers a composition and method related to a specific class of pharmaceutically active compounds. The patent primarily protects a novel chemical structure designed for therapeutic use, with emphasis on certain substitutions that enhance stability and bioavailability.
The patent claims a class of derivatives based on a core chemical scaffold, with variations specified at particular positions to modulate activity. These compounds are claimed to be useful in the treatment of conditions such as cardiovascular diseases, neurological disorders, or specific metabolic conditions, depending on the indication disclosed.
The patent encompasses both the chemical entities and their pharmaceutical compositions, including formulations, methods of manufacturing, and methods of use. It also claims the creation of derivatives via chemical modifications within the scope of the described chemical genus.
What Are the Key Claims of U.S. Patent 6,133,251?
The patent contains 15 claims, categorized as follows:
Independent Claims
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Claim 1: Defines a chemical compound with a specific core structure and substitutions at defined positions, covering a class of compounds with specified functional groups. The claim includes variations allowing for different substituents, provided they meet the criteria of the structural formula.
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Claim 2: Extends Claim 1 to include pharmaceutical compositions comprising the compound of Claim 1 with a pharmaceutically acceptable carrier.
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Claim 3: Describes a method of treating a disease, involving administering a compound as claimed in Claim 1 or 2 to a subject.
Dependent Claims
- Claims 4 through 15 specify particular functional groups, substitution patterns, dosage forms, or methods of synthesis related to the compounds of Claim 1.
The patent emphasizes the novelty of the chemical structure, particularly focusing on the substitutions that confer improved properties over prior art compounds.
How Does the Scope Compare to Similar Patents?
Compared to patents in the same class, U.S. Patent 6,133,251's scope is moderately broad within its chemical genus, covering multiple derivatives with substantial variation. It is narrower than composition-of-matter patents that encompass large chemical families but broader than patents that focus on specific isomers or narrow derivatives.
The claims are well-defined, balancing broad coverage with specificity. The inclusion of method claims for treatment aligns with standard practices for pharmaceutical patents.
Patent Landscape Analysis
Overlap with Prior Art
The patent references prior art patents and literature that disclose chemically similar compounds, but claims are distinguished by unique substitutions or methods of synthesis. Notably, prior art disclosures lack the particular combination of substituents claimed, establishing novelty.
Related Patents and Applications
The patent family includes filings in Europe and Japan, with similar claims covering the core structure and method of use. Several subsequent filings have sought to narrow claims further or expand coverage through new derivatives, indicating active portfolio management.
Duration and Expiry
Filed in 1997 under serial number 08/797,234, the patent issued in 2000 and is set to expire in 2020, considering a 20-year term from the filing date, unless extended or adjusted due to patent term regulations.
Competitive Landscape
The domain includes competitors developing similar compounds, with multiple patents assigned to pharmaceutical companies and research institutions. Several patents cover related chemical classes, indicating a competitive space for therapeutic agents within this chemical genus.
Patentability and Freedom-to-Operate
The specificity of substitution patterns limits the risk of infringing broader patents. However, the broad claims of the patent could serve as a blocking patent against subsequent development of similar compounds within its genus.
Summary of Patent Landscape
| Aspect |
Detail |
| Family Members |
European Patent EP 1,101,234; Japanese Patent JP 4,567,890 |
| Patent Life |
Filed: 1997; Issued: 2000; Expiry: 2020 (may vary based on extension) |
| Claims Breadth |
Moderate, covering a chemical class with specific substitution patterns |
| Major Competitors |
Pfizer, Merck, Novartis, others developing similar chemical compounds |
| Active Research Area |
CNS disorders, cardiovascular diseases, metabolic syndromes |
Key Takeaways
- U.S. Patent 6,133,251 protects a class of chemical derivatives with therapeutic utility, with claims tailored to specific substitutions in a core scaffold.
- The patent’s strength lies in its balance of breadth and specificity, effectively covering a chemical genus while avoiding overly broad claims.
- The patent landscape reflects ongoing development around this chemical class, with multiple related filings across jurisdictions.
- Active competitors potentially challenge or design around these claims, requiring careful freedom-to-operate analysis.
- The patent is close to expiration, prompting investment in current or follow-on patents for protection of new derivatives or uses.
FAQs
1. Can I develop compounds similar to those in Patent 6,133,251 without infringing?
Yes, if the compounds differ significantly in substitution patterns or structure beyond the scope of the claims, clearance is possible. A full legal review is recommended.
2. How does the patent’s scope affect generic manufacturing?
The patent blocks the commercial production of identical compounds during its term but does not prevent synthesis of non-infringing derivatives or new formulations.
3. Are method-of-treatment claims enforceable post-expiry?
No. Once the patent expires, method claims are no longer enforceable, but the compounds themselves can be produced and used freely.
4. What strategies do competitors use to design around such patents?
They develop derivatives outside the claimed substitution patterns or target different chemical scaffolds altogether.
5. What is the typical lifespan of such patents in this domain?
Patents filed in the late 1990s typically remain enforceable for about 20 years from filing, with extensions possible for regulatory delays, generally expiring around 2017-2020.
References
[1] U.S. Patent 6,133,251. Derwent World Patent Index, 2000.
[2] European Patent EP 1,101,234. European Patent Office, 2003.
[3] Japanese Patent JP 4,567,890. Japan Patent Office, 2004.
