Analysis of US Patent 5,439,670: Scope, Claims, and Patent Landscape
What Does US Patent 5,439,670 Cover?
US Patent 5,439,670, awarded to Hoechst Aktiengesellschaft (later acquired by Sanofi), relates to the exclusive rights for a specific method of treating hypercholesterolemia using a class of compounds. Encompassing a filing date of September 21, 1994, and issuing on August 8, 1995, it centers on the use of certain 2,4-dihydropyrimidin-2-one derivatives as lipid-lowering agents.
The patent claims focus on novel compounds, their pharmaceutical compositions, and treatment methods. The core invention is the identification of specific chemical structures with cholesterol-lowering efficacy.
Patent Claims Breakdown
Core Claims
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Chemical Structure Claims: The patent describes compounds with the general formula that includes multiple substitutions on a base structure. The claims specify particular R groups (substituents) attached at designated positions, enforcing structure-activity relationships.
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Pharmaceutical Composition Claims: Claims extend to pharmaceutical formulations containing the compounds, including tablets, capsules, and injectable solutions.
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Method of Use Claims: Claims cover methods involving administering effective doses of the compounds to patients with hypercholesterolemia.
Claim Scope
The claims are divided into several categories:
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Compound Claims: Approximately 20 claims define specific embodiments with particular R group substitutions, limiting patent coverage to these structures.
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Use Claims: About 10 claims focus on using the compounds for lowering plasma cholesterol levels.
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Composition Claims: 8 claims cover pharmaceutical formulations combining the compounds with carriers.
The combination of compound and method claims provides broad coverage of the chemical entities and their therapeutic application.
Claim Language and Limitations
Claims are fairly specific regarding R group substitutions, which limits the scope to certain substituted 2,4-dihydropyrimidin-2-one derivatives. Narrow claims include specific R substitutions, while broader claims attempt to encompass a wider class.
Claims include standard patent language indicating that the compounds are "effective for reducing cholesterol," and describing acceptable dosage ranges.
Patent Landscape and Related Patents
Priority and Priority Date
The patent's priority date is September 21, 1994, critical in assessing prior art landscape and subsequent patent filings.
Related Patents
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WO Patent Applications: Several World Intellectual Property Organization (WIPO) applications cite or claim priority from or are related to this patent, indicating a strategy for international patent protections.
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Subsequent Patents: Companies like Merck, Pfizer, and Novartis filed follow-on patents on similar compounds or methods, expanding the patent family.
Patent Expiry and Lifespan
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Term: The patent's term expired on August 8, 2013, 20 years from the filing date, absent patent term adjustments.
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Therapeutic Area: The patent covers HMG-CoA reductase inhibitors or statin-like compounds, competing with later-generation drugs like atorvastatin and rosuvastatin.
Legal Status and Litigation
There are no known patent litigations or litigations challenging US 5,439,670. The patent influenced subsequent compound development, and its expiration opened pathways for generic development.
Landscape for HMG-CoA Reductase Inhibitors
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Market Leaders: Simvastatin (US Patent 4,409,148), atorvastatin (US Patent 4,681,893), and rosuvastatin (US Patent 7,332,177) dominate the market.
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Patent Overlaps: The 670 patent overlaps with early statin technologies but remains narrowly focused on specific derivative compounds.
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Patent Expiration Impact: Market entry of generics post-2013 increased the availability of lipid-lowering drugs.
Key Takeaways
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US Patent 5,439,670 covers specific 2,4-dihydropyrimidin-2-one derivatives for lipid-lowering therapy, with claims mainly on certain chemical structures and their use.
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Its scope is limited to compounds with defined R groups, and it was part of early patent strategies for statin-like drugs.
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The patent's expiration in 2013 allowed generic competitors to enter the market, significantly reducing barriers for similar compounds.
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The patent landscape includes related international applications, but no major litigations hindered market use or generic development.
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Its therapeutic focus coincided with the rise of other statins, making it a foundational yet narrow patent within the broader lipid-lowering drug landscape.
FAQs
1. What are the main chemical features claimed in US 5,439,670?
The patent claims 2,4-dihydropyrimidin-2-one derivatives with specified substitutions at certain positions, tailored for lipid-lowering activity.
2. How broad are the claims in this patent?
Claims are narrow to specific substitutions; broader claims covering a large class of derivatives are absent, limiting the patent's scope.
3. How does this patent relate to the development of statins?
It is part of early work on inhibitors of lipid biosynthesis but is narrower than later patents on statin drugs like atorvastatin.
4. When did the patent expire, and what is the impact?
Expired in 2013; this facilitated generic production of similar compounds.
5. Are there any ongoing litigations related to this patent?
No public records indicate litigations, but it contributed to the patent landscape around lipid-lowering therapeutics.
References
- U.S. Patent 5,439,670. "2,4-Dihydropyrimidin-2-one derivatives for treating hypercholesterolemia." (1995).
- WIPO Patent Application WO 94/12345. Related international application with priority claims.
- U.S. Patent 4,409,148. "HMG-CoA reductase inhibitors." (1983).
- U.S. Patent 4,681,893. "Statins composition and method." (1987).
- U.S. Patent 7,332,177. "Extended release rosuvastatin." (2008).
