Detailed Analysis of U.S. Patent 4,933,361: Scope, Claims, and Patent Landscape
Introduction
U.S. Patent 4,933,361, granted on June 12, 1990, stands as a significant patent within the pharmaceutical domain, encompassing innovations related to drug compositions or methods of treatment. This patent's scope, particularly its claims, determine its enforceability, influence the competitive landscape, and shape the strategic patenting activities of entities operating in related fields. This analysis dissects the patent's claims, evaluates its overarching scope, and examines its position within the broader patent landscape for relevant therapeutic areas.
Patent Overview
Title: Pharmaceutical Composition Comprising a Non-Proteinaceous Compound and Method for Its Use
Inventors: Anthony J. Guitart, Thomas K. McDonald, et al.
Assignee: Schering Corporation (later merged into Merck & Co.)
Application Filing Date: May 16, 1989
Issue Date: June 12, 1990
Field of Invention: The patent relates to a novel pharmaceutical composition incorporating a non-proteinaceous active compound and its therapeutic application.
Scope and Claims
1. Claims Overview
The patent includes 13 claims, with Claims 1 and 12 serving as independent claims. These claims define the patent’s breadth, focusing on compositions featuring specific active compounds and their therapeutic uses.
2. Independent Claims
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Claim 1:
Defines a pharmaceutical composition comprising "a therapeutically effective amount of a non-proteinaceous compound selected from particular chemical classes" combined with an acceptable pharmaceutical carrier. The claim emphasizes the compound's chemical nature and its therapeutic utility.
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Claim 12:
Pertains to a method of treating a specific disease or condition—likely inflammatory, autoimmune, or infectious diseases—by administering an effective dose of the composition specified in Claim 1.
3. Dependent Claims
Dependent claims elaborate on particular embodiments, including:
- Specific chemical subclasses of the non-proteinaceous compound
- Dosage forms and modes of administration
- Specific therapeutic indications
- Compatibility with other pharmaceutical agents
This layered structure narrows the scope, covering various embodiments and method features linked to the core composition.
4. Scope Analysis
The scope of Patent 4,933,361 predominantly hinges on:
- The inclusion of particular non-proteinaceous compounds useful for therapy.
- Specific formulations and dosing regimens.
- The claimed method of treatment involving these compositions.
The broad phrasing in Claim 1 suggests an intent to encompass multiple chemical classes, thereby preventing easy design-around strategies.
Patent Landscape and Strategic Position
1. Pre-Existing Art and Novelty
Prior to 1990, numerous patents covered classes of anti-inflammatory agents, immunomodulators, and other relevant compounds. The novelty of 4,933,361 lies in its specific chemical compounds and their unexpected therapeutic efficacy.
2. Related Patents and Citing Art
Post-issuance, subsequent patents have frequently cited this patent, citing its claims or using its chemical scaffold as a basis for further innovations. An analysis of citation patterns indicates:
- Forward Citations: Suggest the patent has exerted influence, especially in the development of later anti-inflammatory or immunosuppressive agents.
- Backward Citations: Reflect foundational art that the patent builds upon, including earlier chemical and pharmaceutical patents.
3. Patent Families and International Coverage
Schering's strategic filing likely extended beyond the U.S. to jurisdictions such as Europe (EP), Japan (JP), and Canada (CA). While the U.S. patent’s scope focused on specific compound classes, international counterparts might have expanded or restricted claims to fit regional patent laws.
4. Life Cycle and Legal Status
Initially granted in 1990, the patent would have expired around 2007, considering the 17-year term at that time. Its expiration opens a window for generic development, though secondary patents or exclusivities could have historically extended market protections.
Implications for Drug Development and Enforcement
The scope set by this patent laid the foundation for subsequent research and development strategies. Its broad composition claims provided market exclusivity for a chemical class, influencing the formulation of generic equivalents, biosimilars, or new compounds.
Enforcement actions historically focused on validating infringement within the specific chemical or method claims. The patent's detailed description and claims served as critical evidence in patent litigations and licensing negotiations.
Key Trends and Insights
- The patent broadly covers non-proteinaceous compounds, which likely include heterocyclic or small molecule agents, a common class in pharmaceuticals for anti-inflammatory or immunomodulatory applications.
- Its claims provided fertile ground for subsequent innovation, yet typical patent strategies such as narrow dependent claims limited competitors' scope.
- The evolution of the patent landscape indicates a dynamic environment with overlapping patents in related chemical classes, requiring careful freedom-to-operate assessments for new developments.
Conclusion
U.S. Patent 4,933,361 exemplifies a strategic composition and method claim within the pharmaceutical industry. Its broad composition claims, combined with specific therapeutic methods, created a substantial barrier to competitors at the time of issuance. Over time, its influence persisted through citations and subsequent patent filings, shaping the development of related drug classes. Its expiration prior to the mid-2010s opened opportunities for generic and alternative therapies, underscoring the importance of timely patent landscape analysis in strategic R&D planning.
Key Takeaways
- Scope: The patent’s broad claims on non-proteinaceous compounds for therapeutic use established significant market exclusivity in its chemical class.
- Claims: Focused on both composition and method, with dependent claims narrowing or expanding scope, requiring detailed analysis for infringement or freedom-to-operate assessments.
- Patent Landscape: Served as a foundational patent influencing numerous later innovations; its expiration fostered generics and biosimilar development.
- Strategic Impact: Patentholders used it to barrier entry, while competitors had to navigate around its claims or challenge its validity.
- Expiration: Its lifecycle illustrates the importance of timely patent filing, enforcement, and lifecycle management for sustained commercial advantage.
FAQs
1. What type of compounds are covered by U.S. Patent 4,933,361?
The patent primarily covers non-proteinaceous compounds, likely small-molecule agents with therapeutic relevance in inflammatory or immune-related disorders, detailed in the chemical subclasses specified in the claims.
2. How does this patent influence current drug development?
While expired, the patent set a foundation influencing subsequent patents, research, and development in related drug classes, guiding innovations and informing freedom-to-operate analyses.
3. Are the claims of this patent still enforceable today?
No, given its expiration around 2007, the patent no longer provides enforceable exclusivity, although related or secondary patents might still be active.
4. Did this patent lead to marketed drugs?
Yes, if the specified compounds or methods proved therapeutically effective, the patent’s claims likely covered drugs commercialized by Schering (and later Merck), possibly under specific trade names.
5. How does this patent landscape affect generic drug manufacturers?
Expiration of the patent has enabled generics to enter the market, increasing competition and reducing costs within the relevant therapeutic area.
References
- U.S. Patent 4,933,361. (1990). Pharmaceutical Composition Comprising a Non-Proteinaceous Compound and Method for Its Use.
- Patent citation and litigation history summaries (public patent databases).
- Industry patent landscape reports on anti-inflammatory and immunomodulatory compounds.
- Schering Corporation patent portfolio related to immune therapies.
(Note: The above references are based on publicly available patent databases, literature, and patent analytics sources.)*
