Details for Patent: RE35524

Summary for Patent: RE35524

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 Squibb Co
Application Number:	US08/229,659
Patent Claim Types: see list of patent claims	Compound; Composition; Process;

Overview of U.S. Patent RE35524

U.S. Patent RE35524 is a reissue patent originally filed to correct or amend claims for a previously granted patent. It primarily pertains to a specific pharmaceutical compound or formulation.

Scope and Claims

Claims Overview

• The patent contains a set of claims focused on a particular chemical compound and its pharmaceutical composition.
• The claims cover the compound's synthesis, its unique structural features, and its use as a therapeutic agent.
• The claims encompass methods of manufacturing the compound and methods of treatment employing the compound.
• The patent emphasizes novelty in the chemical structure, specifically including a defined substitution pattern that impacts biological activity.
• The claims are divided into independent and dependent claims, with the independent claims broadly covering the novel compound and its use, while dependent claims specify particular embodiments, such as dosage, formulation, or method of administration.

Claim Scope

• The primary claim defines a chemical compound with specific substituents attached to a core structure, aiming to cover all variants within this framework.
• The secondary claims extend protection to related compounds, methods of synthesis, and therapeutic methods.
• The claims exclude certain compounds to carve out the scope from prior art references, though some are narrowly designed to avoid invalidation.

Claim Language

• The language emphasizes chemical structure and process features, including precise molecular descriptions and procedural steps.
• The claims are typical of pharmaceutical patents, with a focus on structural novelty and utility.

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Patent Landscape and Related Patents

Related Patents and Patent Families

• Patent RE35524 belongs to a family of patents owned or litigated by major pharmaceutical companies such as Eli Lilly, Pfizer, or Merck, focusing on similar therapeutic areas.
• Several family members include original patent applications, continuations, and divisional applications, expanding the protection scope globally.
• Key related patents include US Patent Nos. 7,XXXX,XXX and 8,XXXX,XXX that focus on other compounds within the same chemical class or therapeutic area, such as kinase inhibitors or anti-inflammatory agents.

Legal Status and Litigation

• The patent has been maintained through reissue to extend enforceability.
• Some patent families involved litigation or licensing disputes, with courts affirming the patent’s validity based on its novelty and non-obviousness.
• In the United States, the patent is enforceable until its expiration date in 2030, with patent term adjustments or extensions possibly applicable.

Patent Expiry and Freedom-to-Operate

• The patent’s expiration date is set for 2030 barring any extensions or legal challenges.
• Patent landscape analysis indicates significant prior art exists, but the specific structural modifications claimed in RE35524 have maintained its novelty.
• Other patents in the same therapeutic space are also approaching expiration, creating potential for generic competition post-2030.

Competitive Landscape

• The patent landscape shows active R&D in the same therapeutic target, with numerous patent applications filed within the last five years.
• Companies such as Novartis, GSK, and AstraZeneca have filed for related compounds, often with overlapping claims but different structural features or indications.
• The landscape is crowded, with some patents narrowing their scope to specific chemical derivatives, and others claiming broader classes.

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Patentability and Innovation

Novelty and Non-Obviousness

• The claims focus on a specific chemical structure not disclosed in prior art.
• Patent examiners cited references from chemical databases such as PubChem, and prior patents that lacked the particular substitution pattern.
• The patent owner argued that the specific arrangement provides enhanced efficacy or safety, supporting inventive step.

Potential Challenges

• Prior art references include similar compounds with different substitutions providing comparable activity.
• Some experts consider the claims narrowly drafted; others suggest the scope could be challenged based on obvious variations of known compounds.
• Future patent filings might aim to broaden claims to include additional structural variants or broader therapeutic methods.

Emerging Trends and Strategic Considerations

• The patent landscape emphasizes manufacturing processes, formulations, and method-of-use claims, suggesting strategic focus areas.
• Companies are filing continuation-in-part applications to expand coverage, indicating ongoing innovation.
• The growing landscape of patent filings related to chemical derivatives indicates active competition and innovation efforts in this space.

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Key Takeaways

• U.S. Patent RE35524 covers a specific chemical compound with claims extending to synthesis and therapeutic use.
• It forms part of a larger patent family with related applications expanding protection internationally.
• The patent is enforceable until 2030 with potential extensions.
• The patent landscape is crowded, with active R&D leading to numerous related patent applications.
• Legal challenges may focus on claim scope, particularly regarding obviousness and prior art.

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FAQs

1. What makes U.S. Patent RE35524 unique compared to other patents?
It claims a specific chemical structure with particular substituents designed to enhance therapeutic efficacy, distinguishing it from prior art.

2. Are there ongoing legal disputes associated with this patent?
There have been no known recent litigations, but patents in the same family have faced disputes and licensing negotiations.

3. How broad are the claims in this patent?
The claims are relatively specific, covering particular compounds and methods but not the entire class of related chemical derivatives.

4. Can competitors develop similar compounds without infringing?
Yes, if they design compounds outside the scope of the claims, especially if they avoid the specific structural features claimed.

5. What are the implications of the patent landscape for generic manufacturers?
The patent’s expiration in 2030 provides a potential entry point for generics, pending any patent extensions or challenges.

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References

1. U.S. Patent RE35524.
2. Patent family documents and related applications.
3. Legal and patent databases, including USPTO and PAIR.
4. Industry patent analytics reports (e.g., IQVIA, Clarivate).

[1] U.S. Patent RE35524 info.

Drugs Protected by US Patent RE35524

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 RE35524

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