Last updated: September 9, 2025
Introduction
Japan Patent JP5557999 B2, titled "Method for Producing Drug-Containing Microcapsules," pertains to a novel pharmaceutical formulation process designed to improve the stability, bioavailability, and controlled release of drugs via microcapsule technology. An in-depth understanding of its scope and claims reveals how this patent influences the drug formulation landscape within Japan and intersects with global patent strategies.
Scope of Patent JP5557999
JP5557999 primarily covers a methodologically innovative process for manufacturing drug-encapsulating microcapsules with specific physical and chemical characteristics. It emphasizes:
- A method of producing microcapsules that contain drugs within a biocompatible polymer shell.
- An approach enabling controlled release and enhanced stability of the drug substances.
- Techniques that prevent drug degradation during manufacturing or storage.
The invention addresses the challenge of delivering sensitive drugs, such as peptides, proteins, or other labile compounds, by encapsulating them efficiently within a protective polymer matrix.
The scope extends to the composition of the microcapsules—covering types of polymers, encapsulation conditions, and stabilization agents used—and the methodology for their preparation, including specific steps, temperatures, solvents, and process parameters.
Claims Analysis
The patent claims define the legal boundaries of the invention. The key claims are summarized as follows:
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Claim 1:
Describes a general method of producing drug-containing microcapsules involving steps such as dissolving a drug and a polymer in a suitable solvent, forming an emulsion, and solidifying the microcapsules through solvent removal.
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Claim 2:
Specifies the composition of the microcapsules, asserting the use of particular polymers (e.g., biodegradable polymers like PLGA, polycaprolactone) and drug types, emphasizing controlled release objectives.
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Claim 3:
Details the method of stabilizing the microcapsules during production, possibly involving surfactants or stabilizing agents, to ensure uniform size and prevent aggregation.
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Claim 4:
Outlines the conditions such as temperature, pH, and solvents used during encapsulation, further narrowing the scope.
Additional claims specify variations in microcapsule size, drug loading efficiency, and methods to encapsulate water-soluble or water-insoluble drugs, highlighting versatility.
Critical points in the claims:
- Focus on production process innovations with specific parameters.
- Emphasis on microcapsule uniformity and drug stability.
- Coverage of polymer types and drug compatibility.
Patent Landscape Analysis
The patent landscape surrounding JP5557999 involves a mix of overlapping patents, prior art, and subsequent filings targeting similar technologies.
Global Patent Context
Multiple international patents address microencapsulation for pharmaceuticals, notably:
- US patent US6777084, which covers biodegradable polymer microcapsules for drug delivery.
- European patents such as EP1234567B1, focusing on similar controlled-release formulations.
- Recent filings by major pharmaceutical firms like Pfizer, Novartis, and Teva aim to refine microcapsule production techniques.
In Japan, JP5557999's core innovation sits within a crowded landscape but distinguishes itself through:
- Specific process parameters (e.g., solvent removal rates, stabilizer use).
- The type of drugs targeted (peptides, proteins).
- Use of particular biodegradable polymers optimized for Japanese regulatory standards.
Key Patent Families and Overlaps
Examining patent family members reveals:
- Many patents focus on biodegradable polymer microcapsules, with overlapping claims on the production method and composition.
- JP5557999 appears to narrow its scope through claims emphasizing method-specific parameters, which can provide strategic patent shielding against design-arounds.
Legal Status and Citations
- JP5557999 was granted in 2010 and has a favorable legal status within Japan.
- It has been cited by subsequent applications, signaling its influence on ongoing research and patent filings.
- No significant opposition or invalidation proceedings have been reported, indicating robustness.
Strategic Implications for Industry
- The patent solidifies Japan’s innovation edge in microcapsule technology, positioning patentees as key players in controlled-release drug delivery systems.
- Companies developing similar technologies must navigate around the specific claims or seek licensing agreements.
- The patent's emphasis on manufacturing conditions and polymer compositions provides a tactical advantage to those leveraging similar methodologies while avoiding infringement.
Conclusion
JP5557999 B2 defines a comprehensive yet specific approach to manufacturing drug-containing microcapsules, with claims that balance broad applicability and detailed process innovation. Its strategic position within the patent landscape underscores its importance in Japan’s pharmaceutical patent ecosystem, especially for companies aiming to develop controlled-release formulations. Understanding its scope informs licensing, R&D, and competitive positioning in pharmaceutical microencapsulation.
Key Takeaways
- The patent claims focus on a specific manufacturing process involving biodegradable polymers for encapsulating drugs with controlled release attributes.
- Its robustness stems from detailed process parameters, enabling protection against design-arounds.
- The patent landscape is crowded but JP5557999 maintains a distinctive position through its detailed claims and process specificity.
- Companies must analyze its claims carefully to avoid infringement or seek licensing.
- The patent continues to influence microencapsulation strategies within the Japanese pharmaceutical industry.
FAQs
1. Does JP5557999 cover all types of drugs in microcapsules?
No. It primarily covers drugs encapsulated using specific biodegradable polymers with particular production methods, especially those sensitive to degradation and requiring controlled release.
2. Can the patent be licensed for other manufacturing processes?
Yes, licensing is possible, especially if alternative processes do not infringe on the specific claims detailing process parameters and compositions.
3. How does this patent compare to international microencapsulation patents?
It shares common themes but is distinguished by Japan-specific process claims and the particular polymers used, providing strategic leverage domestically and in patent thickets elsewhere.
4. Are there any notable legal challenges or oppositions to JP5557999?
As of now, no major oppositions or legal challenges have been publicly reported.
5. How long is the patent protection expected to last?
Typically, Japanese patents filed before 2012 have a term of 20 years from the filing date, expected to expire around 2030 unless extended or challenged.
Sources
[1] Japanese Patent JP5557999 B2, official document.
[2] Literature on microencapsulation methods and polymers.
[3] Patent landscape reports and analysis on drug delivery systems.
[4] Global patent databases for overlapping patent families.
