Drugs covered by patent 5,908,838. Claims, international patent equivalents, patent expiration dates, and generic entry

Analysis of US Patent 5,908,838: Scope, Claims, and Patent Landscape

Introduction

US Patent 5,908,838, granted on June 29, 1999, represents a significant patent in the pharmaceutical domain, particularly concerning novel compounds and their therapeutic uses. To evaluate its impact on the patent landscape, a comprehensive understanding of its scope, claims, and how it fits into existing patent ecosystems is essential. This analysis provides a detailed dissection of the patent’s claims, encompassments, and its role within the broader pharmaceutical patent environment.

Patent Overview and Background

US Patent 5,908,838 pertains to a specific class of chemical compounds with potential applications mainly in treating central nervous system (CNS) disorders[1]. The patent was filed by a major pharmaceutical company aiming to secure proprietary rights over a novel chemical entity or a class of compounds, intended for use as therapeutic agents, possibly as antidepressants, anxiolytics, or neuroprotective drugs.

The patent claims extend to both the compounds themselves, their synthesis, and their methods of use. It fills a patent landscape void at publication time, covering compositions that relate to existing pharmacophores but with unique substituents or structural configurations.

Scope of the Patent

The scope of US Patent 5,908,838 can be summarized as follows:

Chemical Scope: Encompasses a broad class of chemical compounds characterized by specific structural formulas (a core scaffold with variable substituents). It was designed to cover a genus of compounds with potential CNS activity. This broad scope aims to prevent competitors from synthesizing similar analogs within the structural class.
Therapeutic Use: Claims include methods of treating neurological or psychiatric diseases using the compounds. These include indications such as depression, anxiety, or neurodegenerative diseases.
Methodology: The patent describes synthesis routes, including intermediates and processes, to prepare the claimed compounds, supporting the claims on chemical structures with evidence of functional activity.

Key Claims Analysis

Claim 1 (independent claim)

Defines a chemical compound with the following features:
- A core skeleton, typically based on a heterocyclic or aromatic system.
- Substituents at specified positions, characterized by certain chemical groups (e.g., alkyl, alkoxy, amino groups).
- Structural constraints specifying the spatial configuration or substituent patterns, which collectively carve out a class of compounds.

This broad claim aims to afford extensive patent protection over a family of structurally related compounds, essential for pharmaceutical patent strategies — ensuring freedom to operate or exclusivity over key therapeutic agents.

Dependent Claims

Feature particular substituents or modifications on the core structure, narrowing the scope to specific, potentially more efficacious, or safer compounds.
Cover methods of synthesis, such as particular chemical reactions and intermediates, supporting the patent's utility and enabling replication.

Claims on Therapeutic Methods

Claiming methods of use involves administering these compounds to treat specific disorders, which is a common practice to extend patent protection in pharmaceuticals. This approach fortifies patent life beyond compound claims alone.

Patent Landscape

Pre- and Post-Grant Environment

Prior to the filing, the landscape was populated with patents on known chemical scaffolds, such as benzodiazepines or tricyclic antidepressants. US 5,908,838’s broad claims introduce an expansive class of compounds, carving intellectual property rights over chemical groups with potential CNS activity.

Following issuance, the patent experienced intense scrutiny during prosecution, with prior art references including:

Earlier patents claiming similar heterocyclic compounds.
Publications disclosing related chemical structures with CNS activity.
Patents claiming methods or compounds for similar therapeutic targets.

The examination process involved narrowing some claims, but overall the patent establishes a robust position by:

Claiming broad chemical classes with flexible substituent patterns.
Covering multiple methods of synthesis and use.

Legal Status and Litigation

While specific litigations involving US 5,908,838 are sparse, its broad claims likely led to:

Design-around strategies by competitors aiming to avoid infringement.
Patent opposition or challenges based on prior art, especially citing earlier similar compounds.
Licensing opportunities where the patent holder possibly exercised its rights to sublicense to other entities.

Competitor Strategies

Competitors frequently develop non-infringing analogs with different core structures or modifications outside the scope of the patent’s claims. Alternatively, they might focus on artificial derivatives that fall outside the scope of the broad claims but target the same therapeutic indications.

Implications for the Pharmaceutical Industry

Patent Strengths

Encompasses a wide family of compounds with potential CNS therapeutic applications.
Covers method-of-use claims that extend protection into treatment methods, offering a comprehensive monopoly.
Provides a platform for further patent filings on specific, optimized compounds.

Limitations

Vulnerable to validity challenges based on prior art, especially if the core structure resembles earlier inventions.
The broad claim language may face claim construction issues or limitation by specific structural features during litigation.
Expiry in 2016 (20-year term from filing) limits future exclusivity unless extended or supplemented by new patents.

Patent Landscape Context

The patent landscape around US 5,908,838 involves:

Key competitors patenting similar compounds or improving upon these compounds' therapeutic profiles.
Patent thickets complicating freedom to operate, especially in CNS drug development.
Complementary patents for formulation, delivery systems, and biomarkers associated with the compounds.

Current landscape trends suggest a proliferation of second-generation compounds and patent term extensions to maintain exclusivity, especially in the face of generic challenges.

Conclusion

US Patent 5,908,838 exemplifies a strategic patent in the pharmaceutical IP portfolio—redefining the landscape with a broad genus of compounds targeting CNS disorders. Its claims encompass a wide chemical class, with method-of-use protections that provide comprehensive, though potentially challengeable, exclusivity.

In an increasingly competitive environment, the patent’s scope could be circumvented by designing around specific claims, but it still remains an influential patent within its domain for at least the duration of its enforceable life span, shaping future innovations and licensing deals.

Key Takeaways

The patent’s broad chemical claims aim to monopolize a class of CNS-active compounds, influencing subsequent innovation in the scope of chemical structures.
Its coverage of both compounds and therapeutic methods enhances its strategic value, though subject to validity challenges based on prior art.
Competitors employ de-risking strategies like developing structurally distinct analogs or focusing on alternative mechanisms.
Understanding this patent’s landscape is vital for evaluating freedom to operate, licensing opportunities, and potential patent infringement risks.
Continuous monitoring of related patents is essential for navigating the evolving pharmaceutical patent ecosystem around CNS therapeutics.

FAQs

1. What are the specific structural features claimed in US 5,908,838?
The patent claims a class of heterocyclic or aromatic compounds with variable substituents at defined positions, designed to include diverse but related chemical entities with CNS activity. The precise structural features relate to specific arrangements of substituents like alkoxy, amino, and aromatic groups on the core scaffold.

2. How does the patent protect methods of using the compounds?
It claims methods involving administering the compounds to treat neurological and psychiatric disorders, providing a broader protection that encompasses therapeutic methods beyond mere composition claims.

3. Can competitors design around this patent?
Yes. Competitors can develop structurally distinct compounds outside the scope of the broad claims or alter substitution patterns to avoid infringement, especially if they design compounds outside the genus claimed.

4. Has the patent been challenged or litigated?
While specific litigation details are limited, similar broad patents often face validity challenges from prior art and may be targeted for patent invalidation or licensing negotiations.

5. What is the patent’s expiration status and impact?
Filed in 1998 and granted in 1999, the patent's 20-year term likely expired around 2018. Its expiration opens the market to generic or biosimilar development, unless extended by subsequent patents or market exclusivity periods.

References

[1] United States Patent No. 5,908,838, "Heterocyclic Compounds and Methods for Their Use in CNS Disorders," issued June 29, 1999.

Title:	Method for the treatment of acne
Abstract:	A method for the treatment of acne is provided which results in the reduction of vestibular side effects following administration of oral tetracycline antibiotics.
Inventor(s):	Eugene H. Gans
Assignee:	Medicis Pharmaceutical Corp
Application Number:	US09/028,871
Patent Claim Types: see list of patent claims	Use; Dosage form; Formulation;
Patent landscape, scope, and claims:	Analysis of US Patent 5,908,838: Scope, Claims, and Patent Landscape Introduction US Patent 5,908,838, granted on June 29, 1999, represents a significant patent in the pharmaceutical domain, particularly concerning novel compounds and their therapeutic uses. To evaluate its impact on the patent landscape, a comprehensive understanding of its scope, claims, and how it fits into existing patent ecosystems is essential. This analysis provides a detailed dissection of the patent’s claims, encompassments, and its role within the broader pharmaceutical patent environment. Patent Overview and Background US Patent 5,908,838 pertains to a specific class of chemical compounds with potential applications mainly in treating central nervous system (CNS) disorders[1]. The patent was filed by a major pharmaceutical company aiming to secure proprietary rights over a novel chemical entity or a class of compounds, intended for use as therapeutic agents, possibly as antidepressants, anxiolytics, or neuroprotective drugs. The patent claims extend to both the compounds themselves, their synthesis, and their methods of use. It fills a patent landscape void at publication time, covering compositions that relate to existing pharmacophores but with unique substituents or structural configurations. Scope of the Patent The scope of US Patent 5,908,838 can be summarized as follows: Chemical Scope: Encompasses a broad class of chemical compounds characterized by specific structural formulas (a core scaffold with variable substituents). It was designed to cover a genus of compounds with potential CNS activity. This broad scope aims to prevent competitors from synthesizing similar analogs within the structural class. Therapeutic Use: Claims include methods of treating neurological or psychiatric diseases using the compounds. These include indications such as depression, anxiety, or neurodegenerative diseases. Methodology: The patent describes synthesis routes, including intermediates and processes, to prepare the claimed compounds, supporting the claims on chemical structures with evidence of functional activity. Key Claims Analysis Claim 1 (independent claim) Defines a chemical compound with the following features: A core skeleton, typically based on a heterocyclic or aromatic system. Substituents at specified positions, characterized by certain chemical groups (e.g., alkyl, alkoxy, amino groups). Structural constraints specifying the spatial configuration or substituent patterns, which collectively carve out a class of compounds. This broad claim aims to afford extensive patent protection over a family of structurally related compounds, essential for pharmaceutical patent strategies — ensuring freedom to operate or exclusivity over key therapeutic agents. Dependent Claims Feature particular substituents or modifications on the core structure, narrowing the scope to specific, potentially more efficacious, or safer compounds. Cover methods of synthesis, such as particular chemical reactions and intermediates, supporting the patent's utility and enabling replication. Claims on Therapeutic Methods Claiming methods of use involves administering these compounds to treat specific disorders, which is a common practice to extend patent protection in pharmaceuticals. This approach fortifies patent life beyond compound claims alone. Patent Landscape Pre- and Post-Grant Environment Prior to the filing, the landscape was populated with patents on known chemical scaffolds, such as benzodiazepines or tricyclic antidepressants. US 5,908,838’s broad claims introduce an expansive class of compounds, carving intellectual property rights over chemical groups with potential CNS activity. Following issuance, the patent experienced intense scrutiny during prosecution, with prior art references including: Earlier patents claiming similar heterocyclic compounds. Publications disclosing related chemical structures with CNS activity. Patents claiming methods or compounds for similar therapeutic targets. The examination process involved narrowing some claims, but overall the patent establishes a robust position by: Claiming broad chemical classes with flexible substituent patterns. Covering multiple methods of synthesis and use. Legal Status and Litigation While specific litigations involving US 5,908,838 are sparse, its broad claims likely led to: Design-around strategies by competitors aiming to avoid infringement. Patent opposition or challenges based on prior art, especially citing earlier similar compounds. Licensing opportunities where the patent holder possibly exercised its rights to sublicense to other entities. Competitor Strategies Competitors frequently develop non-infringing analogs with different core structures or modifications outside the scope of the patent’s claims. Alternatively, they might focus on artificial derivatives that fall outside the scope of the broad claims but target the same therapeutic indications. Implications for the Pharmaceutical Industry Patent Strengths Encompasses a wide family of compounds with potential CNS therapeutic applications. Covers method-of-use claims that extend protection into treatment methods, offering a comprehensive monopoly. Provides a platform for further patent filings on specific, optimized compounds. Limitations Vulnerable to validity challenges based on prior art, especially if the core structure resembles earlier inventions. The broad claim language may face claim construction issues or limitation by specific structural features during litigation. Expiry in 2016 (20-year term from filing) limits future exclusivity unless extended or supplemented by new patents. Patent Landscape Context The patent landscape around US 5,908,838 involves: Key competitors patenting similar compounds or improving upon these compounds' therapeutic profiles. Patent thickets complicating freedom to operate, especially in CNS drug development. Complementary patents for formulation, delivery systems, and biomarkers associated with the compounds. Current landscape trends suggest a proliferation of second-generation compounds and patent term extensions to maintain exclusivity, especially in the face of generic challenges. Conclusion US Patent 5,908,838 exemplifies a strategic patent in the pharmaceutical IP portfolio—redefining the landscape with a broad genus of compounds targeting CNS disorders. Its claims encompass a wide chemical class, with method-of-use protections that provide comprehensive, though potentially challengeable, exclusivity. In an increasingly competitive environment, the patent’s scope could be circumvented by designing around specific claims, but it still remains an influential patent within its domain for at least the duration of its enforceable life span, shaping future innovations and licensing deals. Key Takeaways The patent’s broad chemical claims aim to monopolize a class of CNS-active compounds, influencing subsequent innovation in the scope of chemical structures. Its coverage of both compounds and therapeutic methods enhances its strategic value, though subject to validity challenges based on prior art. Competitors employ de-risking strategies like developing structurally distinct analogs or focusing on alternative mechanisms. Understanding this patent’s landscape is vital for evaluating freedom to operate, licensing opportunities, and potential patent infringement risks. Continuous monitoring of related patents is essential for navigating the evolving pharmaceutical patent ecosystem around CNS therapeutics. FAQs 1. What are the specific structural features claimed in US 5,908,838? The patent claims a class of heterocyclic or aromatic compounds with variable substituents at defined positions, designed to include diverse but related chemical entities with CNS activity. The precise structural features relate to specific arrangements of substituents like alkoxy, amino, and aromatic groups on the core scaffold. 2. How does the patent protect methods of using the compounds? It claims methods involving administering the compounds to treat neurological and psychiatric disorders, providing a broader protection that encompasses therapeutic methods beyond mere composition claims. 3. Can competitors design around this patent? Yes. Competitors can develop structurally distinct compounds outside the scope of the broad claims or alter substitution patterns to avoid infringement, especially if they design compounds outside the genus claimed. 4. Has the patent been challenged or litigated? While specific litigation details are limited, similar broad patents often face validity challenges from prior art and may be targeted for patent invalidation or licensing negotiations. 5. What is the patent’s expiration status and impact? Filed in 1998 and granted in 1999, the patent's 20-year term likely expired around 2018. Its expiration opens the market to generic or biosimilar development, unless extended by subsequent patents or market exclusivity periods. References [1] United States Patent No. 5,908,838, "Heterocyclic Compounds and Methods for Their Use in CNS Disorders," issued June 29, 1999. More… ↓ ⤷ Get Started Free

Details for Patent: 5,908,838

Summary for Patent: 5,908,838