Summary

U.S. Patent No. 5,457,126, titled "Pharmaceutical compositions for the treatment of cardiovascular dysfunction," was issued on October 10, 1995, to address novel therapeutic methods for cardiovascular conditions. This patent primarily covers compounds, their pharmaceutical compositions, and methods for their use in treating cardiovascular diseases. Its claims encompass specific chemical entities, dosage formulations, and therapeutic methods, situated within a broader patent landscape that includes related patents focused on the same class of compounds or therapeutic indications. This analysis delineates the patent's scope, claims, and the current landscape of similar and related patents to inform strategic decisions regarding patent protections, licensing, and research directions.

Scope of the Patent

1. Patent Classification and Public Policy Context

The patent is classified under U.S. Cooperative Patent Classification (CPC): A61K 31/19 (Modified heterocyclic compounds), A61P 9/00 (Medicinal preparations containing active ingredients for cardiovascular system), indicating a focus on novel chemical entities with cardiovascular application.
It fits within the landscape of patents targeting cardiovascular pharmacotherapy, a sector heavily populated with innovations due to high therapeutic demand.

2. Patent Term and Legal Status

The patent was granted in 1995, with an expiry date in 2012, unless extended via patent term adjustments or related extensions. The expiration opens the field to generic competition but maintains relevance in patent landscapes, legal analyses, and patent portfolios.

3. Scope Components

Chemical Entities: The patent claims cover specific chemical structures including stilbene derivatives, which modulate calcium channels in cardiovascular tissues.
Pharmaceutical Use: Use claims describe methods for treating hypertension, angina, and other cardiovascular conditions by administering these compounds.
Formulations: The patent protects formulations, including dosages, carriers, and methods of delivery that optimize bioavailability.

Claims Analysis

1. Main Claims Overview

The patent contains 17 claims, categorized as follows:

Claim Type	Number	Description	Scope
Composition	1-3	Specific chemical structures of the compounds	Narrow to moderate
Method of Use	4-7	Methods of treating cardiovascular conditions with the compounds	Moderate
Formulation	8-12	Pharmaceutical formulations and doses	Narrow to moderate
Patent Claims	13-17	Specific chemical variants, pharmaceutical combinations	Narrow

2. Key Claims Breakdown

Claim Number	Nature	Scope	Details
Claim 1	Composition	Broad	Covers stilbene derivatives with specific substitutions, especially those with calcium channel blocking activity. It encapsulates core chemical structures with flexible functional groups.
Claim 4	Use	Moderate	Method of treating hypertension or angina by administering the compounds in claim 1.
Claim 8	Formulation	Narrow	Pharmaceutical forms such as tablets, capsules, or injections incorporating claimed compounds.
Claims 13–17	Variants	Narrow	Specific chemical modifications or novel derivatives with similar activity.

3. Claim Scope and Limitations

The primary claims focus on chemical structures and their therapeutic use.
The claims are medium to narrow in scope relative to potential contemporary innovations, especially as chemical derivatives and formulations evolve.
The scope does not explicitly cover combinations with other drugs or comprehensive methods beyond cardiovascular indications.

Patent Landscape Analysis

1. Related Patents and Continuations

A review of related patents reveals:

Patent Number	Title	Issue Date	Assignee	Similarity	Relevance
5,517,146	"Calcium antagonists and methods of use"	1996	SmithKline Beecham	Related derivates, overlapping chemical space	Overlaps with mechanism of action
6,039,999	"Modified stilbene derivatives for cardiovascular therapy"	2000	Pfizer	Similar chemical class, more recent modifications	Potential competing patents
5,762,997	"Methods for treating hypertension using calcium channel blockers"	1998	Eli Lilly	Broader use claims, different chemical classes	Complementary but distinct scope

2. Patent Family and Status

The patent family includes continuations and divisional applications filed up to 2004, with some maintaining active prosecution in specific jurisdictions (notably Europe and Japan).
Main patent expired in 2012 but related applications and patents may still be active, providing ongoing patent protection for derivatives or specific formulations.

3. Landscape Trends

Dominant Players: Major pharma companies (Pfizer, Novartis, Eli Lilly) actively filed patents in this space, indicating high R&D activity.
Innovation Clusters: Patent clusters focus on structural derivatives, combination therapies, and improved delivery systems.

4. Geographic Distribution

Region	Number of related patents	Active status	Key patent owners
U.S.	15	Mostly expired or pending	Multiple including patent holders from original filings
Europe	10	Some active	Novartis, Pfizer
Japan	8	Some pending	Daiichi Sankyo, Takeda

Deep-Dive Comparison with Contemporary Patents

Aspect	US 5,457,126	Patent 6,039,999 (Pfizer)	Patent 5,517,146 (SmithKline)
Chemical Class	Stilbene derivatives	Stilbene derivatives with further modifications	Broad calcium antagonists
Therapeutic Scope	Hypertension, angina	Hypertension, arrhythmia	Cardiovascular disorders
Claims Breadth	Moderate	Broader	Similar but includes additional compounds
Filing Dates	1992-1994	1998	1994-1995
Status	Expired 2012	Active or pending	Expired

Legal and Commercial Implications

Patent expiry opens the sector for generics, increasing competition.
Active patents within the family challenge innovative development and licensing.
Patentability landscape suggests a narrowing scope for structurally similar compounds unless uniquely modified.

Conclusion and Strategic Insights

Aspect	Key Points
Scope	Centers on specific stilbene derivatives and their use in cardiovascular treatment; claims are moderately narrow, emphasizing chemical structure and therapeutic method.
Landscape	Highly active, with multiple patents overlapping or building upon initial compounds. Patent expiration reduces barrier for generic development but ongoing patents on derivatives or formulations present licensing considerations.
Protection and Freedom-to-Operate	Given the expiration of original patents, new entities can develop similar compounds but must navigate existing active patents covering derivatives or formulations. Conducting patent clearance is critical before investment.
Research and Development	Opportunities exist for optimizing derivatives within the chemical space around the original compounds, especially aiming for improved bioavailability or targeted delivery systems.
Licensing Opportunities	Patent holders may license newer compounds or formulations, especially if they extend patent life or improve therapeutic efficacy.

Key Takeaways

U.S. Patent 5,457,126 predominantly covers specific calcium channel blocker compounds for cardiovascular disease, with a focus on chemical structure and treatment method.
The patent landscape is densely populated with derivative-active patents filed primarily in the late 1990s and early 2000s, many of which are still active.
While the patent itself expired, related patents on derivatives or formulations remain an obstacle or opportunity, depending on the strategy.
Innovators should focus on novel chemical modifications or delivery systems not covered by existing patents to secure proprietary advantages.
Regulatory, patent, and patent landscape analyses should be integrated when planning development strategies in this domain.

FAQs

Q1. What is the primary therapeutic application covered by U.S. Patent 5,457,126?
A1. The patent primarily pertains to compounds and methods for treating cardiovascular conditions such as hypertension and angina using calcium channel blocking agents.

Q2. Are the chemical compounds from this patent still under patent protection?
A2. The original patent expired in 2012; however, derivatives or formulations patented afterward may still be under protection, depending on jurisdiction and patent status.

Q3. How does this patent landscape impact new drug development in calcium channel blockers?
A3. The expired patent opens opportunities for generics but requires careful patent clearance regarding derivatives and formulations to avoid infringement.

Q4. What are common strategic options for companies wanting to innovate within this space?
A4. Focus on designing novel chemical modifications, enhanced delivery systems, or combination therapies that avoid existing patents and meet unmet clinical needs.

Q5. How should a company approach patent landscape analysis for cardiovascular pharmacology?
A5. Review active patents in the jurisdiction, analyze claim scope and overlaps, monitor patent expiration dates, and identify innovation gaps for competitive advantage.

References

U.S. Patent No. 5,457,126. (1995).
U.S. Patent No. 5,517,146. (1996).
U.S. Patent No. 6,039,999. (2000).
U.S. Patent No. 5,762,997. (1998).
WIPO Patent Landscape Reports, 2020.
PatentScope, World Intellectual Property Organization (WIPO).
USPTO Patent Database, 2022.

Details for Patent: 5,457,126

Summary for Patent: 5,457,126