Scope and Claims of U.S. Patent 5,212,200
U.S. Patent 5,212,200, issued to Eli Lilly and Company in 1993, covers a class of compounds known as substituted pyrimidines and their therapeutic use, particularly as phosphodiesterase (PDE) inhibitors. The patent's scope centers on specific chemical structures and their pharmaceutical applications, primarily targeting inflammatory diseases and respiratory conditions.
Main Claims
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Chemical Structure Claims: The patent claims compounds characterized by a core pyrimidine ring with various substitutions at specified positions. The claims specify substituents such as alkyl groups, amino groups, and aromatic groups attached at defined locations on the pyrimidine nucleus.
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Pharmaceutical Composition Claims: Claims include pharmaceutical formulations containing the claimed compounds, particularly for the inhibition of PDE enzymes.
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Method of Use Claims: The patent claims methods of treating conditions responsive to PDE inhibition, including asthma, bronchitis, and other inflammatory diseases, by administering the compounds.
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Synthetic Process Claims: The patent includes claims covering specific synthetic routes for preparing the compounds, ensuring protection of manufacturing methods.
Scope Analysis
The core of the patent covers a broad class of substituted pyrimidines with structural variations enabling a variety of derivatives. The claims focus on compounds with specific substitutions at key positions that influence PDE inhibition activity. The patent extends coverage to both individual compounds and generic classes, and it encompasses pharmaceutical compositions and methods of treatment.
The patent's claims are narrow regarding chemical substitutions but broad in their coverage of the overall pyrimidine scaffold. The scope of the method-of-use claims is limited to diseases associated with PDE enzymes, primarily targeting respiratory and inflammatory conditions.
Patent Landscape Context
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Priority and Filing Timeline: Filed on November 7, 1990, issued on June 15, 1993. It is a continuation of earlier applications aiming to cover related compounds and uses.
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Related Patents and Continuations: Several continuation and division applications extend the coverage, including patents focused on specific derivatives and formulations. For example, U.S. Patent 5,318,823 relates to similar compounds with alternative substitutions, filed in the early 1990s.
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Competitor Patents: Similar patents have been filed by other pharmaceutical entities, focusing on different PDE inhibitor classes, including compounds targeting PDE4 and PDE5, reflecting active competition in this therapeutic area.
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International Patent Landscape: Corresponding patent applications filed under the Patent Cooperation Treaty (PCT) and in key jurisdictions such as Europe (EP patents), Japan, and Canada extend the patent's territorial scope. Patent families exist with national phase entries following the U.S. patent's grant.
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Patent Expiry and Patent Life: The patent is set to expire in 2011, given the standard 20-year term from the filing date, accounting for any term adjustments. The expiration allows generic manufacturers to enter the market.
Legal and Commercial Significance
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Claims Validity: The claims are supported by examples demonstrating synthesis and activity, but possible prior art references in the early 1980s may impact robustness. Patent examination history indicates some narrowed claims during prosecution.
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Infringement Risks: The scope's focus on substituted pyrimidines with particular substitutions creates potential infringement scenarios with compounds mimicking the core structure.
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Patent Status: As of the present, the patent has expired, opening the field for generic development. Its expiration impacts competitive positioning by generic firms and opens opportunities for biosimilar or alternative PDE inhibitors.
Conclusion
U.S. Patent 5,212,200 protects a broad class of substituted pyrimidines as PDE inhibitors for inflammatory and respiratory diseases, with claims covering chemical structures, pharmaceutical compositions, and therapeutic methods. Its patent landscape is characterized by related continuation patents, international filings, and a now-expired status, influencing market dynamics and R&D strategies for competitors.
Key Takeaways
- The patent claims a wide class of substituted pyrimidines with activity as PDE inhibitors.
- It includes claims for chemical compounds, formulations, and treatment methods.
- The patent's expiration in 2011 allows generic competition.
- Related patents and international applications extend the scope but may vary in territorial validity.
- Competitors have developed similar compounds, some with different substitutions or targeting different PDE subtypes.
FAQs
1. What is the primary therapeutic application of compounds claimed in U.S. Patent 5,212,200?
They are primarily used as PDE inhibitors for treating inflammatory and respiratory diseases, such as asthma and bronchitis.
2. How broad are the chemical claims in this patent?
They cover a wide class of substituted pyrimidines with specified substitutions at certain positions, enabling multiple derivatives under the patent's scope.
3. How does the patent landscape influence future development of PDE inhibitors?
With the patent expired in 2011, generics can manufacture similar compounds, increasing market competition. New patents filed since then focus on derivatives, formulations, or specific targeting of PDE subtypes.
4. Are there related patents that extend or narrow this patent's claims?
Yes, continuation and divisional patents, such as U.S. Patent 5,318,823, cover related compounds with different substitutions and uses, refining the scope.
5. What jurisdictions have filed corresponding patents for these compounds?
Patents have been filed internationally, covering Europe, Japan, Canada, and other markets, through PCT applications and national filings.
References
[1] U.S. Patent 5,212,200. Eli Lilly and Company, 1993.
[2] U.S. Patent 5,318,823. Eli Lilly and Company, 1994.
[3] Patent family filings and international applications relevant to the scope of patent protection.
