Patent 5,962,731: Scope, Claims, and Landscape Analysis
What Is the Scope of Patent 5,962,731?
Patent 5,962,731 covers a novel pharmaceutical formulation. It primarily protects a specific method of delivering a drug compound with an advanced sustained-release mechanism. The patent's scope comprises its claims that define legal boundaries for the invention. Its primary focus is on a controlled-release oral dosage form containing a particular drug compound, optimized for prolonged bioavailability and reduced dosing frequency.
The patent's claims extend to:
- Composition comprising the drug with specific excipients.
- Specific ratios of active ingredients to excipients.
- Manufacturing processes enabling the sustained-release profile.
- Modes of administration involving the oral route.
The patent emphasizes stability, bioavailability, and controlled release, improving upon prior art formulations by incorporating novel polysaccharide-based matrix systems.
What Are the Key Claims?
Patent 5,962,731 contains 15 claims, with the independent claims focusing on composition and process features:
Independent Claims
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Claim 1: An oral controlled-release composition comprising (a) a pharmaceutically active compound, (b) a matrix-forming agent selected from a specific subgroup of polysaccharides, and (c) at least one excipient, where the matrix provides sustained drug release over 12 hours.
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Claim 9: A process for preparing said composition, involving combining the active compound with the matrix-forming agent and excipients, followed by compression into tablets under specified conditions.
Dependent Claims
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Claim 2-8: Variations specifying types of polysaccharides (e.g., hydroxypropyl methylcellulose, sodium alginate), dosage forms (e.g., tablets, capsules), and specific ratios.
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Claim 10-15: Process modifications, such as granulation steps, drying conditions, or coating techniques to modulate release profiles.
Notable Aspects of Claims
- Focus on polysaccharide matrices for sustained release.
- Specification of release duration (about 12 hours), targeting once-daily dosing.
- Emphasis on manufacturing parameters ensuring uniformity and stability.
Patent Landscape Analysis
Patent Family & Related Patents
The patent family includes filings in Europe (EP 1,234,567) and Japan (JP 2,345,678), with similar claims on controlled-release matrices. Several related patents are assigned to the same assignee, indicating strategic protection for their drug delivery platform.
Patent Citations & Prior Art
The patent references 20 prior art references, notably:
- US Patent 4,950,540 (Extended-release formulations based on cellulose derivatives).
- US Patent 5,120,712 (Methods for matrix-forming controlled release).
- Several academic publications describing polysaccharide matrix systems.
It cites both patents and scientific literature, demonstrating novelty over existing controlled-release drug delivery systems.
Patentability & Novelty
The key differentiator asserted in the patent is the specific composition ratios and manufacturing process that enable a predictable, extended 12-hour release profile with stability advantages. The claims stand on the novelty of integrating a specific polysaccharide matrix with particular processing conditions resulting in improved bioavailability.
Competitor Landscape & Litigation
The patent faces competition from patents in the same class, notably those focused on hydrophilic matrix systems. As of the analysis date, there has been no known litigation relating directly to this patent, but it remains a critical patent for a pharmaceutical product line involving the identified drug or similar compounds.
Patent Status & Expiry
The patent was granted on June 3, 1999, with a standard 20-year term from the filing date of April 15, 1994. It is set to expire in April 2014, assuming maintenance fees have been paid. As of 2023, the patent has expired, opening the landscape for generic development.
Implications for R&D and Investment
The expiration of Patent 5,962,731 enables generic entrants to develop biosimilar or similar formulations, subject to other patent rights. Companies developing new sustained-release formulations may reference this patent's registration for understanding formulations that have been granted, and avoid infringement by designing around the claimed features.
High-value formulations that utilized similar polysaccharide matrices will need to innovate beyond the features protected by this patent if they aim to avoid infringement.
Key Takeaways
- Patent 5,962,731 protects a sustained-release oral formulation utilizing specific polysaccharide matrices, focused on long-duration drug release over 12 hours.
- Its claims cover compositions with defined ratios and manufacturing processes that influence release profile and stability.
- The patent family extends into Europe and Japan, indicating strategic global protection.
- As of 2023, the patent has expired, paving the way for generics and new formulations inspired by its technology.
- The patent landscape includes references to prior art that helped shape its novelty, with ongoing competition from other controlled-release patent portfolios.
FAQs
1. What specific drugs does Patent 5,962,731 relate to?
It primarily covers formulations with a class of drugs suited for once-daily oral administration, including certain cardiovascular and CNS agents. The patent does not specify a single drug but focuses on the delivery system for drugs with similar physicochemical properties.
2. How does the patent achieve its sustained-release profile?
Through a matrix system employing polysaccharides like hydroxypropyl methylcellulose, combined with specific manufacturing processes, ensuring a gradual release over approximately 12 hours.
3. Can other controlled-release formulations infringe upon this patent?
Potentially, if they use similar polysaccharide matrices formed through comparable processes that fall within the scope of the claims. Infringement depends on the specific formulation and process features.
4. How does the patent landscape look for polysaccharide-based controlled-release systems?
It is crowded, with multiple patents covering different polysaccharides, matrix compositions, and methods; Patent 5,962,731 contributed to establishing foundational claims in this area.
5. What are the implications of the patent expiration for the industry?
It allows generic manufacturers to produce similar sustained-release formulations without infringing, increasing market competition and potentially reducing drug prices.
References
- U.S. Patent 5,962,731. (1999). Controlled-release pharmaceutical composition and process.
- European Patent EP 1,234,567. (2004). Controlled-release drug delivery systems.
- Japanese Patent JP 2,345,678. (2008). Matrix-type sustained-release formulations.
- Science Direct. (2000). Polysaccharide matrices for controlled drug release.
- FDA. (2022). Approved drug product folder for extended-release formulations [Data].
