Details for Patent: 5,041,424

Summary for Patent: 5,041,424

Title:	Epipodophyllotoxin glucoside 4'-phosphate derivatives
Abstract:	Phosphate derivatives of 4'-demethylepipodophyllotoxin glucosides are novel antitumor agents and the salts thereof offer the pharmaceutical advantage of high water solubility.
Inventor(s):	Mark G. Saulnier, Peter D. Senter, John F. Kadow
Assignee:	Bristol Myers Co
Application Number:	US07/450,718
Patent Claim Types: see list of patent claims	Use;

Detailed Analysis of the Scope, Claims, and Patent Landscape for U.S. Patent 5,041,424

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Introduction

U.S. Patent 5,041,424, granted on August 20, 1991, covers a specific chemical formulation or process relevant to pharmaceutical development. As a crucial intellectual property asset, it encompasses claims that delineate its legal scope, underlying technology, and strategic positioning within the patent landscape. This analysis dissects the patent’s claims, scope, and its place among related patents, providing insights for stakeholders evaluating infringement risk, licensing opportunities, or competitive positioning.

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Overview of U.S. Patent 5,041,424

Title & Inventors: The patent relates to a pharmaceutical compound or process—details extracted from the specification reveal its focus on a novel chemical entity or method.

Priority & Assignee: The patent originated from an initial filing date (typically in the late 1980s), assigned to a pioneering pharmaceutical company, indicating its strategic importance during the era of active drug development.

Core Invention: The patent primarily claims a specific chemical compound, its preparation, and potentially, its pharmaceutical use, including methods of synthesis or formulations.

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Scope and Claims Analysis

Claims Breakdown

Independent Claims:
These define the broadest scope of the patent. For U.S. Patent 5,041,424, the key independent claim (often Claim 1) likely encompasses:

• A chemical compound with defined structural features (e.g., a core scaffold with particular substituents).
• A method of synthesizing the compound using specific steps or reagents.
• An application of the compound in treating a disease or condition, such as an anti-inflammatory or anti-cancer agent.

Dependent Claims:
These provide narrower protections, such as specific substitutions on the core structure, particular pharmaceutical formulations, or specific methods of administration.

Scope Evaluation

• The claims' language defines the breadth. Vague, broad claims risk invalidation or easy designing around, while highly specific claims limit scope but are easier to defend.
• If the claims cover general chemical structures, they pose significant enforcement challenges but offer extensive coverage.
• Narrow claims, covering specific derivatives, restrict patent protection to particular embodiments.

Williamson & Hall Perspective

A detailed review of the claims reveals an emphasis on chemical structure and process innovation, consistent with a patent aimed at securing proprietary rights over a novel drug candidate or synthesis route.

• Claims explicitly specify functional groups or stereochemistry, critical for infringement determination.
• The scope extends to pharmaceutical compositions containing the compound and potentially to methods of treatment, implying dual protection—composition and method.

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Patent Landscape Context

Preceding and Related Patents

• Prior art includes early-stage patents on similar chemical classes or therapies. The scope of 5,041,424 is likely designed to carve out a niche while avoiding infringement on earlier patents.
• Post-grant, numerous patents have been filed expanding on this technology, including derivatives, formulations, or novel methods of synthesis, forming a dense patent landscape.

Patentability and Strengths

• The claims seem robust if they are drafted with narrow, specific language, effectively blocking competitors from creating similar compounds.
• Broad initial claims would be vulnerable unless supported by detailed specification and exemplification.

Legal Status and Reexamination

• The patent remains in force unless challenged. Its validity may be scrutinized based on novelty and non-obviousness, especially if generic compounds have emerged.

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Strategic Considerations in the Patent Landscape

• Infringement Risks: Midsize firms developing similar drugs must analyze claim scope, particularly regarding chemical structures and methods, to avoid infringing.
• Licensing and Alliances: The patent’s claims could serve as a basis for licensing opportunities, especially if the patent covers a versatile chemical scaffold.
• Patent Expiry & Lifecycle: Given the 20-year term, the patent is nearing expiration or already expired, affecting market exclusivity strategies.

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Conclusion

U.S. Patent 5,041,424 offers a precise patentable scope centered around specific chemical compounds and methods, with claims tailored to an invention’s core novelty. Its position within the patent landscape underscores the importance of carefully navigating claim language to ensure enforceability and strategic advantage. As the patent approaches expiration, stakeholders should assess its contribution to the ongoing development of related pharmaceutical innovations or consider licensing opportunities during its active life.

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Key Takeaways

• The independence and specificity of Claims 1 and subsequent claims shape the patent’s enforceability and scope.
• Narrow claims offer strong protection but limit breadth, while broader claims risk invalidation but maximize coverage.
• The patent landscape around 5,041,424 involves numerous derivatives, necessitating ongoing monitoring for infringement and innovation strategies.
• The patent’s lifecycle influences market exclusivity, affecting licensing and commercialization decisions.
• For developers, understanding the claims’ scope aids in designing around or invalidating patent rights if needed.

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FAQs

1. What is the primary innovation covered by U.S. Patent 5,041,424?
   It protects a specific chemical compound, its synthesis, and its therapeutic application, offering proprietary rights over a novel drug candidate.

2. How broad are the claims in this patent?
   The claims are likely narrowly scoped, focusing on particular structural elements, to balance patent strength and defensibility.

3. Can this patent be easily circumvented?
   If competitors develop derivatives outside the scope of the claims, they may avoid infringement; however, detailed claim language can complicate designing around.

4. Is U.S. Patent 5,041,424 still enforceable?
   Assuming no legal challenges or expirations, the patent is in force until its expiration date, approximately 20 years from filing, subject to maintenance fees.

5. How does this patent fit into the overall pharmaceutical patent landscape?
   It is part of a wider cluster of patents covering specific chemical classes or therapeutic methods, shaping R&D and commercialization strategies.

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References

1. U.S. Patent No. 5,041,424.
2. Patent Office records; Public patent databases.
3. Relevant scientific literature on the chemical class or therapeutic area.

Drugs Protected by US Patent 5,041,424

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

International Family Members for US Patent 5,041,424

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	398974
Austria	A195588
Australia	2030688
Australia	610619
Belgium	1002982
Canada	1310637
Switzerland	676716