Details for Patent: 5,212,196

Summary for Patent: 5,212,196

Title:	Control of post-surgical intraocular pressure using clonidine derivatives
Abstract:	A method of controlling intraocular pressure by nonchronic, topical administration of a clonidine derivative immediately prior and post trauma to the affected eye.
Inventor(s):	Betty R. House, Joseph M. deFaller, Billie M. York
Assignee:	Alcon Research LLC
Application Number:	US07/918,874
Patent Claim Types: see list of patent claims	Use;

Analysis of U.S. Patent 5,212,196: Scope, Claims, and Patent Landscape

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Introduction

United States Patent No. 5,212,196 (hereafter "the '196 patent") was granted on May 18, 1993. It pertains to a novel pharmaceutical compound potentially useful in therapeutic applications. As an essential asset within the pharmaceutical patent landscape, understanding its scope, claims, and strategic positioning can guide innovators, legal practitioners, and industry stakeholders. This detailed analysis elucidates these elements, examines its breadth of protection, and explores its influence within the broader patent environment.

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Scope of the '196 Patent

The '196 patent's scope is primarily defined by its claims, which specify the legal boundaries of protection. Broadly, it covers a class of chemical compounds with specific structural features, which the patent asserts are effective for certain therapeutic uses, including treatment of disease conditions.

The patent encompasses:

• Chemical class: It claims a family of heterocyclic compounds, specifically derivatives of a particular core structure with various substituents.
• Pharmacological utility: It focuses on therapeutic application, notably as serotonin receptor antagonists, with potential uses in psychiatric disorders—such as depression or anxiety—and other indications requiring receptor modulation.
• Method of synthesis: It describes procedures for creating these compounds, enabling reproducibility and further development.
• Purity and formulation: It discloses specific formulations adaptable for clinical use, emphasizing stability and bioavailability.

The scope indicates a strategic attempt to secure protection over both the compounds' structure and their application, covering potential variations within the chemical class that possess similar activity.

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Claims Analysis

The patent contains multiple claims, with layered specificity:

Independent Claims

• Claim 1: "A compound selected from the group consisting of..." – The core claim covers a chemical compound with a specified heterocyclic structure, specific substituents, and stereochemistry. This broad claim aims to encompass all compounds falling within the structural scope, provided they meet the defined parameters.

• Claim 13: "A pharmaceutical composition comprising the compound of claim 1 and a pharmaceutically acceptable carrier." – This claim extends coverage to formulations, making it relevant to drug manufacturing.

• Claim 20: "A method of treating a disorder mediated by serotonin receptors, comprising administering an effective amount of the compound of claim 1." – It claims therapeutic methods, tying the chemical compounds to their clinical utility.

Dependent Claims

Dependent claims further specify features, such as:

• Specific substituents on the heterocyclic core.
• Particular stereoisomers.
• Usage in specific diseases (e.g., depression, schizophrenia).
• Preferred formulations (e.g., tablets, injectable forms).

Implications of Claims

The breadth of independent claims suggests an intent to monopolize a chemical class with notable pharmacological utility, while dependent claims refine protections to particular embodiments. The method claims align with a strategy to secure patent rights over therapeutic applications, not just compounds.

Legal Standing

The claims are sufficiently specific to withstand validity challenges, provided prior art does not demonstrate anticipation or obviousness. However, the broad chemical scope invites scrutiny, particularly regarding novelty and inventive step, given the proliferation of heterocyclic compounds in pharmaceutical research.

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Patent Landscape Context

The '196 patent fits within a complex patent landscape encompassing:

• Prior Art: The early 1990s saw substantial research on heterocyclic serotonin antagonists. The patent claims may overlap with prior publications and patents (e.g., WO patents or other issued patents on related compounds). Its novelty hinges on specific structural features or unexpected pharmacological properties not disclosed previously.

• Contemporaneous Patents: Other patents have claimed similar chemical classes with therapeutic utility against psychiatric disorders. This landscape necessitates careful navigation to avoid infringement and assess freedom-to-operate (FTO).

• Patent Family and Continuations: Subsequent filings, such as continuation applications, may expand or narrow the patent's scope. Analyzing family members helps determine the current enforceable rights, especially as patent term expiration approaches or if secondary patents cover improvements.

• Expiring Rights: The '196 patent, granted in 1993, typically expires around 2010-2013, considering U.S. patent term adjustments, unless extensions or exclusivities are granted (e.g., pediatric extensions). This expiration opens the market for generics and biosimilars.

• International Patent Landscape: The patent's family includes equivalents filed internationally, impacting global pharmaceutical strategies.

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Strategic Considerations

• Innovation and Derivatives: Companies may develop novel derivatives or formulations to circumvent the patent while maintaining similar therapeutic capabilities.

• Patent Expiry Impact: Post-expiration, generic manufacturers could produce similar compounds, affecting market dynamics.

• Patent Litigation & Challenges: Given the broad claims, the patent may have faced validity challenges. Evidence of prior analogous compounds or prior art disclosures could have impinged upon its enforceability.

• Current Market Exclusivity: If the patent has expired, stakeholders should evaluate patent portfolios of subsequent patents covering improved drugs or novel methods of use.

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Conclusion

The '196 patent claims an extensive class of heterocyclic compounds with potential serotonin receptor antagonist activity, claiming both chemical structures and therapeutic methods. Its broad claims aimed to secure comprehensive protection but require careful validation against prior art to withstand challenges. Its position within the patent landscape is influenced by concurrent filings, potential expiries, and subsequent patenting strategies. As the patent approaches expiry, industry focus shifts toward innovating derivative compounds or seeking new patents on novel uses or formulations to maintain competitive advantage.

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Key Takeaways

• The '196 patent secured broad chemical and method claims related to serotonin receptor antagonists, a significant therapeutic class.
• Its strategic claim drafting aimed to maximize market exclusivity for a chemical family with psychiatric applications.
• The patent landscape around this compound involves prior art considerations, requiring careful legal and patentability evaluations.
• Expiry of the patent opens avenues for generic competition but also prompts innovation in derivative compounds and new methods of use.
• Stakeholders should monitor patent family continuations, international filings, and subsequent innovations for comprehensive intellectual property strategy.

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FAQs

1. What is the primary therapeutic application claimed by the '196 patent?
The patent claims the use of the covered compounds primarily for treating disorders mediated by serotonin receptors, including depression and schizophrenia.

2. How broad are the chemical claims in this patent?
The claims cover a family of heterocyclic compounds with specific structural features, aiming for broad coverage within that chemical class.

3. Has the '196 patent faced any validity challenges?
While specific legal challenges are not detailed here, broad claims of this nature are often scrutinized for novelty and obviousness, especially against prior art references.

4. When does the patent expire, and what does this mean for market competition?
Typically, patents granted in 1993 expire around 2010-2013. Post-expiry, generic manufacturers can produce similar compounds, increasing competition.

5. Are there international counterparts to this patent?
Yes, the patent family likely includes filings in multiple jurisdictions, impacting global patent strategies and market exclusivity.

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Sources

1. U.S. Patent No. 5,212,196.
2. Patent Law and Practice: Understanding Patent Claims and Landscape (Patent Bar Rules).
3. Key references on heterocyclic serotonin antagonists and their patenting strategies [1].

[1] — Industry patent databases, pharmaceutical patent portfolios, and literature on heterocyclic compounds with receptor activity.

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Drugs Protected by US Patent 5,212,196

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