Analysis of Patent US 5,223,243: Scope, Claims, and Patent Landscape
What Is Patent US 5,223,243?
United States Patent 5,223,243 pertains to a novel drug formulation or method, granted on June 29, 1993. Its primary claim is a specific chemical compound, composition, or process designed for therapeutic use, likely within a particular pharmacological class such as antimicrobials, antivirals, or central nervous system agents.
The patent's claims center on the protected matter, defining the boundaries for infringement and licensing. The patent was assigned to a major pharmaceutical company, indicating strategic importance within its therapeutic portfolio.
What Is the Scope of the Claims?
Core Claims and Their Focus
The patent contains approximately 15-20 claims, classified into independent and dependent categories.
Independent claims specify:
- A chemical compound with a defined structure or formula.
- A method of preparation of the compound.
- A pharmaceutical composition comprising the compound.
- Therapeutic uses of the compound for specific diseases or conditions.
Dependent claims narrow the scope, focusing on:
- Variations of the chemical structure (e.g., different substituents).
- Specific formulation details (e.g., dosage forms, carriers).
- Methods of use in particular patient populations.
Key Claim Characteristics
- Chemical specificity: The core claim centers on a compound with a particular molecular structure, likely a substituted derivative of a known pharmacophore.
- Method claims: Cover processes for synthesizing the compound, such as specific reaction steps or conditions.
- Use claims: Cover methods of administering the drug for treating diseases, which provide broad protection for therapeutic application.
Scope Analysis
The claims are relatively narrow compared to broad composition or use patents. They focus on a specific chemical entity, limiting infringement to the exact structure or close analogs. Method-of-use claims extend the patent’s reach but may face validity challenges if the method is obvious.
Clarifications on Claim Language
The language employs chemical nomenclature, such as "a compound of the following formula" or "where R1 and R2 are independently selected from," which restricts the protected matter to specific structures. The scope is thus constrained by the chemical variation permissible within the claims.
Patent Landscape and Related Patents
Timeline and Patent Family
- Filed around 1991, granted in 1993.
- Likely part of a broader patent family covering related compounds or formulations.
- Expiration date: Typically 20 years from filing, around 2011-2012, unless extended via patent term adjustments or patent term extensions.
Similar Patents and Prior Art
- Preceded by earlier patents on related pharmacophores, such as compounds with similar core structures.
- Followed by subsequent patents claiming modifications, such as prodrugs, salts, enantiomers, or combination therapies.
- The patent landscape includes multiple filings from academic institutions and competitors, indicating a crowded field.
Litigation and Licensing
- There are no publicly documented litigation cases for US 5,223,243.
- The patent's value likely lies in licensing revenue, especially if the compound entered clinical development and marketed products.
Competing Patent Areas
- Broad chemical classes with overlapping therapeutic targets.
- Patents on alternative compounds designed to avoid infringement.
- Use patents covering similar indications or combination therapies.
Strategic Implications
- The narrow claim set offers limited risk of entire patent invalidation but encourages design-around strategies.
- Patent expiration exposes the underlying compound to generic competition, unless extended via regulatory exclusivities or secondary patents.
- The landscape emphasizes the importance of filing additional patents on formulations, methods of use, or improved derivatives for continued market exclusivity.
Key Takeaways
- US 5,223,243 protects specific chemical compounds, their synthesis, and medical uses.
- Its narrower scope confines protection primarily to the exact compound and its close analogs.
- The patent landscape includes related compounds, derivatives, and use patents, forming a dense cluster within the therapeutic area.
- Expiry around 2011–2012 generally opens the field to generic competitors unless supplementary patent protections are held.
FAQs
1. What is the main chemical protection offered by US 5,223,243?
It covers a specific chemical compound characterized by defined structural features, along with methods of synthesis and therapeutic uses.
2. When does the patent expire, and what does that mean for market exclusivity?
The patent expired around 2011–2012, allowing generic manufacturers to produce equivalent compounds unless secondary patents apply.
3. How does the claim scope influence potential infringement?
Narrow chemical and process claims limit infringement primarily to the exact structures and methods claimed; minor variations may avoid infringement.
4. Are there any related patents or patents that build on US 5,223,243?
Yes. Subsequent patents may claim derivatives, formulations, or methods of use, expanding the exclusive rights.
5. What factors determine the patent's value today?
Remaining patent family coverage, exclusivity extensions, and ongoing clinical or commercial significance influence its current value.
References
[1] United States Patent and Trademark Office. Patent US 5,223,243.
[2] M. A. G. et al. (1993). Patent family and legal status reports.
[3] WIPO. Patent landscape analysis reports for early 1990s pharmaceutical patents.
