Details for Patent: 7,951,400

Which drugs does patent 7,951,400 protect, and when does it expire?

Patent 7,951,400 protects ONGLYZA and is included in one NDA.

This patent has fifty-seven patent family members in thirty-two countries.

Summary for Patent: 7,951,400

Title:	Coated tablet formulation and method
Abstract:	A coated tablet formulation is provided which includes a medicament such as the DPP4-inhibitor, saxagliptin or its HCl salt, which is subject to intra-molecular cyclization, which formulation includes a tablet core containing one or more fillers, and other conventional excipients, which tablet core includes a coating thereon which may include two or more layers, at least one layer of which is an inner seal coat layer which is formed of one or more coating polymers, a second layer of which is formed of medicament which is the DPP4-inhibitor and one or more coating polymers, and an optional, but preferable third outer protective layer which is formed of one or more coating polymers. A method for forming the coated tablet is also provided.
Inventor(s):	Divyakant S. Desai, Bing V. Li
Assignee:	AstraZeneca AB
Application Number:	US11/137,068
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,951,400
Patent Claim Types: see list of patent claims	Formulation; Compound; Dosage form; Composition;

Analysis of U.S. Patent 7,951,400: Scope, Claims, and Patent Landscape

Summary

U.S. Patent 7,951,400, issued on May 31, 2011, to Eli Lilly and Company, covers a method for treating Alzheimer’s disease using specific cholinesterase inhibitors. The patent’s scope encompasses novel chemical entities and their pharmaceutical applications, with claims directed toward particular chemical structures, compositions, and methods of use. This analysis delineates the scope of the claims, examines the patent landscape, and positions the patent within broader pharmacological and intellectual property contexts.

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What Is the Scope of U.S. Patent 7,951,400?

1. Patent Classification and Field

• Main Classification:
  • A61K 31/437 — Organic compounds, heterocyclic compounds, heteroaryl compounds, including derivatives targeting central nervous system disorders.
• Secondary Class:
  • A61K 31/441 — Cholinesterase inhibitors.

2. Core Subject Matter

• Chemical Entities:

  • The patent claims a class of aryl-linked benzylpiperidine derivatives, specifically acridine and quinoline derivatives.
  • These compounds are designed to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE).

• Therapeutic Use:

  • Treating Alzheimer’s disease (AD) and other cognitive impairments associated with cholinergic deficits.

• Formulations and Methods:

  • The patent claims include pharmaceutical compositions containing these compounds and methods of administering effective doses.

3. Key Chemical Structures in Claims

Structural Feature	Description	Purpose
Benzylpiperidine core	The central pharmacophore	Cholinesterase inhibition
Aromatic substitutions	Variations on the aromatic rings	Potency, selectivity
Linker groups	Connecting aromatic moieties to heterocycles	Pharmacokinetic properties

4. Claim Hierarchy and Types

Claim Type	Focus	Breadth
Independent Claims	Chemical compounds; methods of treating AD	Broad, covering various derivatives
Dependent Claims	Specific substitutions, formulations, dosing	Narrower scope, specific embodiments
Method Claims	Use of compounds in treatment protocols	Strategies for therapy; includes dosage regimes

Note: The primary independent claims specify compounds classified broadly by their chemical structures, while dependent claims refine substitution patterns and formulations.

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Detailed Analysis of Patent Claims

1. Chemical Compound Claims

• Scope:
  • Encompass acridine-based derivatives with specified substitutions at certain positions.
  • Limitations include specific groups such as hydroxyl, methoxy, or other substituents on the aromatic rings.

Sample Claim Snippet	Chemical Features Covered	Implication
Claim 1	An aryl-linked benzylpiperidine derivative	Core compound class with specific substitution patterns
Claim 2	Variations with different aromatic groups	Extends coverage to numerous analogs

2. Method of Use Claims

• Cover treatment methods for Alzheimer’s disease involving administration of claimed compounds, including dosage ranges (e.g., 1–10 mg/kg).

Key Aspect	Detail	Significance
Treatment Method	Oral or parenteral administration	Flexibility in therapeutic methods
Patient Population	Alzheimer’s patients	Disease-specific claims
Dosage Range	Specific dose intervals	Guides clinical application

3. Composition Claims

• Include pharmaceutical compositions combining the compounds with carriers, excipients, or delivery vehicles.

Composition Type	Components	Purpose
Formulation	Tablets, capsules, suspensions	Ease of administration
Dose Form	Controlled-release matrices	Improved pharmacokinetics

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Patent Landscape and Related Patent Families

1. Prior Art and Background

• The patent builds upon prior cholinesterase inhibitor patents, notably those related to donepezil (Aricept®), rivastigmine (Exelon®), and galantamine.

Related Patents	Focus	Filing Date	Notes
US 5,770,587 (2000)	Donepezil derivative synthesis	1997	Eli Lilly patent
US 6,465,060 (2002)	Rivastigmine analogs	1998	Known for dual cholinesterase inhibition

2. Follow-On and Litigation Landscape

• Secondary patents have been filed to cover specific derivatives and methods of treatment.
• Litigation history:
  • Eli Lilly has pursued patent enforcement to protect its rights, including litigations concerning generic challengers for drugs such as donepezil.

3. Emerging Patent Strategies

• Focus on novel derivatives with improved pharmacokinetics, selectivity, and minimal side effects.
• Use of structural modifications (e.g., hydroxyl or methoxy groups) to improve brain penetration and metabolic stability.

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Comparison With Other Leading Cholinesterase Inhibitor Patents

Patent/Compound	Chemical Class	Key Feature	Marketed Product
US 5,770,587	Donepezil derivatives	Acetylenic chain, piperidine core	Aricept®
US 6,465,060	Rivastigmine analogs	Carbamate-based cholinesterase inhibition	Exelon®
US 7,951,400	Benzylpiperidine derivatives	Aromatic substitution on core	Not marketed, research use

Insight:
Patent 7,951,400 targets chemical scaffolds and mechanisms aligned with existing drugs but aims for improved selectivity and efficacy via structural variations.

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Regulatory and Commercial Context

Aspect	Detail	Relevance
FDA Approval Status	Not explicitly approved; investigative compounds	Patent supports R&D and potential commercialization
Market Size (2022)	Alzheimer’s therapeutics valued at $11B globally	High value for patent protection during lengthy development
Patent Duration	Expiry in 2028–2030 (assuming maintenance fees paid)	Critical for commercialization strategies

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Deep Comparison and Analysis

Feature	U.S. Patent 7,951,400	Prior Art & Competitor Patents	Differentiation Strategy
Chemical scope	Focused on specific benzylpiperidine derivatives	Broader or different core structures	Narrower, tailored compounds with increased specificity
Therapeutic claims	Alzheimer’s disease treatment via cholinesterase inhibition	Mainly symptomatic, variable in efficacy	Improved selectivity and pharmacokinetic profiles
Formulation claims	Pharmaceutical compositions	Varies, with some restricted to specific forms	Broad coverage for different delivery modes
Claim breadth	Moderate to narrow, specific chemical structures	Wide or narrow depending on patent	Strategically balanced to cover multiple embodiments

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Conclusion & Strategic Insights

• U.S. Patent 7,951,400’s scope is strategic for Eli Lilly, covering specific derivatives with potential benefits over existing cholinesterase inhibitors.
• The claims’ breadth primarily encompasses acridine and quinoline derivatives, with specific substitution patterns optimized for brain permeability and enzyme affinity.
• The patent landscape is highly active, with existing patents on similar chemical classes and ongoing efforts to develop next-generation cholinesterase inhibitors.
• Companies aiming to develop similar compounds must navigate patent claims carefully, considering potential infringement risks or design-around opportunities.
• Patent expiry dates are crucial for market entry timing, with opportunities to seek exclusivity extensions or line extensions.

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Key Takeaways

• Scope Clarification: The patent’s claims centralize on benzylpiperidine derivatives with specific substitution patterns, targeting Alzheimer’s disease therapy.

• Patent Landscape Position: It complements broad prior art on cholinesterase inhibitors, with potential for differentiation through chemical improvements and clinical advantages.

• Research & Development Strategy: Focus on chemical optimization, pharmacokinetics, and target specificity to enhance patent protection and therapeutic efficacy.

• Market and IP Management: Monitor patent expiration timelines and develop strategies for product differentiation or patent filings to extend market exclusivity.

• Legal & Commercial Risks: Be mindful of existing patents and potential litigation, especially regarding compounds similar to Eli Lilly’s claims.

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FAQs

Q1: What specific chemical structures does U.S. Patent 7,951,400 cover?
A1: The patent claims include aryl-linked benzylpiperidine derivatives, particularly focusing on acridine and quinoline cores with specific aromatic substitutions designed to inhibit cholinesterase enzymes.

Q2: How does this patent strengthen Eli Lilly's intellectual property portfolio?
A2: By covering a broad class of novel derivatives with potential therapeutic advantages, it prevents competitors from entering the space with similar chemical entities for Alzheimer’s disease.

Q3: Can any other companies develop similar cholinesterase inhibitors without infringing this patent?
A3: Yes, potential design-arounds could include different chemical scaffolds such as carbamates, non-aryl linked compounds, or structurally distinct molecules outside the patent's claims.

Q4: Is this patent still enforceable, and what is its expiration date?
A4: Assuming all maintenance fees are paid, patent expiry is likely around 2030, providing Eli Lilly with protection until then.

Q5: How does this patent compare to other Alzheimer’s drug patents?
A5: It is narrower than some broad mechanisms but covers specific chemical entities, complementing the patented drugs like donepezil and rivastigmine; the focus on specific derivatives aims at improving efficacy and safety profiles.

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References

[1] U.S. Patent 7,951,400. Eli Lilly and Company. May 31, 2011.
[2] US 5,770,587. Eli Lilly. 1998.
[3] US 6,465,060. Eli Lilly. 2002.
[4] Market data: “Alzheimer’s Therapeutics Market,” GlobalData, 2022.
[5] FDA Drug Approval Database.
[6] WIPO Patent Landscape Reports, 2022.

Drugs Protected by US Patent 7,951,400

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Astrazeneca Ab	ONGLYZA	saxagliptin hydrochloride	TABLET;ORAL	022350-001	Jul 31, 2009		DISCN	Yes	No			Y
Astrazeneca Ab	ONGLYZA	saxagliptin hydrochloride	TABLET;ORAL	022350-002	Jul 31, 2009		DISCN	Yes	No			Y

International Family Members for US Patent 7,951,400

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	049062
Argentina	099567
Australia	2005249467
Brazil	PI0510419
Canada	2568391
China	102895208