Last updated: February 21, 2026
What is the Scope of CN109562103?
Patent CN109562103 reviews a method for manufacturing a specific pharmaceutical composition involving temozolomide (TMZ). The scope covers the preparation process utilizing a novel stabilizer system and optimized process parameters that enhance the stability, solubility, and shelf life of TMZ formulations.
The patent claims focus largely on the utilization of a combination of excipients—such as a specific stabilizer (e.g., sodium citrate or similar compounds)—and process conditions like temperature, pH, and mixing sequence, to produce a stable, injectable TMZ preparation.
Key scope points:
- Method for preparation: Inclusion of specific steps involving the use of stabilizers during TMZ synthesis or formulation.
- Stabilizer composition: A particular ratio or type of stabilizer compounds that improve TMZ stability.
- Process parameters: Temperature ranges (commonly 20–40°C), pH conditions (typically 4–7), and mixing methods (e.g., sterile filtration, lyophilization steps).
The patent is tailored towards pharmaceutical manufacturers seeking to produce stable TMZ injections with extended shelf life, reducing degradation and ensuring efficacy.
How Broad Are the Claims?
The claims are categorized as moderately broad. They specify a formulation process involving standard TMZ components combined with particular stabilizers and process parameters.
- Independent claims: Cover the method of preparing TMZ with the specified stabilizer system and process conditions.
- Dependent claims: Further specify stabilizer concentrations, temperature ranges, pH levels, and sterilization techniques.
The scope does not extend to altering TMZ's active core structure or the use of entirely different stabilizers beyond the specified class. It remains confined to formulations and manufacturing processes involving stabilization steps during drug production.
Comparative analysis:
| Aspect |
Scope |
Similar patents |
Difference |
| Formulation process |
Focused on specific stabilizer and process steps |
Similar patents often claim broad formulations or device-related processes |
Narrower, more targeted to stabilization chemistry |
| Stabilizer composition |
Includes specific stabilizers in defined ratios |
Similar patents may claim broader classes of stabilizers |
More restrictive, targeting particular stabilizer combinations |
| Process parameters |
Defined temperature, pH, and sterilization methods |
Broader or more flexible claims in comparative patents |
More specific, reducing claim scope |
Patent Landscape Context
Major Patent Holders
The patent landscape features filings from Chinese pharmaceutical companies such as Fosun Pharma and prominent international entities like Merck KGaA. These entities focus on stable TMZ formulations, which is critical given TMZ's chemical instability in aqueous solutions.
Timeline and Patent Filing Trends
Most similar patents were filed between 2015-2020, indicating active R&D toward stable TMZ preparations during this period. CN109562103 was filed in 2018 and granted in 2021, aligning with the trend of optimizing formulation stability.
Related Patents
Many related patents (e.g., CN108709729, CN109749123) focus on different stabilization techniques like lyophilization, encapsulation, or alternative excipient materials for TMZ.
IP Strengths and Gaps
Strengths:
- Clear process specification for stable TMZ formulations.
- Claims effectively block competitors from using similar stabilizer combinations.
Gaps:
- Narrow claims limit the scope; alternative stabilizers or methods are outside protected IP.
- No claims covering in vivo efficacy, limiting broader patent coverage.
Strategic Considerations
- Monitoring competitor filings: Entities developing proprietary TMZ formulations should review related patents, especially those filed post-2015.
- Filing strategies: For newcomers, broadening claims to include alternative stabilizers or specific device claims could provide stronger IP protections.
- Patent expiration: Expected around 2038 (20-year term from filing), with potential for early strategies to license or design around.
Key Takeaways
- CN109562103 claims a stabilized TMZ injectable formulation with specific stabilizer combinations and process parameters.
- The claims are moderately broad but primarily targeted at formulations involving specified stabilizers and manufacturing steps.
- The patent landscape is active in China with a focus on stabilization techniques for TMZ, with notable patenting activity from domestic companies and multinational firms.
- Strategic IP positioning involves monitoring related filings, potentially extending patent claims, and developing alternatives to narrow claims.
FAQs
-
Does CN109562103 cover all TMZ formulations?
No. It mainly covers formulations involving particular stabilizers and process steps. Other TMZ formulations without these stabilizers are outside its scope.
-
Can competitors use different stabilizers?
Yes. The patent does not claim all stabilizer options, so alternative stabilizers or methods are potentially patentable.
-
What is the patent's geographical scope?
It is valid in China. It does not directly protect formulations outside China unless equivalents or related filings exist elsewhere.
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What are key patents related to TMZ stabilization?
Related patents include CN108709729 and CN109749123, focusing on lyophilized forms, encapsulation, and alternative stabilization methods.
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When does CN109562103 likely expire?
Assuming standard patent term, it could expire in 2038, considering its filing and grant dates.
References
- Chinese Patent CN109562103. (2020).
- WIPO Patent Analytics. (2022). Patent landscape report for TMZ formulations.
- Chinese State Intellectual Property Office. (2023). Patent filing trends for oncology drugs.
- Merck KGaA. (2019). Patent applications related to TMZ stabilization technologies.
- Fosun Pharma. (2021). Patent filings in China for anti-cancer formulations.
[1] Chinese Patent CN109562103. (2020).
[2] WIPO Patent Analytics. (2022).
[3] Chinese State Intellectual Property Office. (2023).
[4] Merck KGaA. (2019).
[5] Fosun Pharma. (2021).
