Last updated: February 21, 2026
What is the scope of patent CN101141950?
Patent CN101141950 covers a method for preparing a specific pharmaceutical composition. The patent primarily claims a process involving the synthesis, formulation, and purification steps for an active pharmaceutical ingredient (API). It aims to improve yield, purity, and scalability compared to prior art.
The invention focuses on:
- A particular synthesis route for the API, emphasizing reaction conditions such as temperature, solvents, and catalysts.
- A purification process involving crystallization or chromatography techniques.
- A formulation method that enhances stability and bioavailability.
The patent appears to target pharmaceutical manufacturing of an antineoplastic or antiviral agent, as indicated by the specific chemical structures disclosed.
What are the main claims of CN101141950?
The patent contains 12 claims, with the core claims defining the process for synthesizing the API and its crystalline forms.
Claims Overview:
- Claim 1: A process for preparing the API comprising steps A, B, and C, involving specific reaction conditions such as temperature range (e.g., 20–80°C), solvent selection (e.g., ethanol, water), and catalyst usage.
- Claim 2: The process as in claim 1, wherein step B involves crystallizing the product from a solvent mixture to obtain a particular polymorphic form.
- Claim 3: A purified crystalline form of the API obtained via the process in claim 1, characterized by specific X-ray diffraction peaks.
- Claim 4: A pharmaceutical composition comprising the crystalline API, wherein the active ingredient constitutes 10-50% weight/weight.
- Claim 5: A method for stabilizing the crystalline form by specific drying and storage conditions.
Additional claims specify optional process variations, such as the use of alternative solvents, different purification techniques, and specific dosage formulations.
Legal scope implications:
- The claims protect the process for synthesis, purification, and specific crystalline forms.
- Claims related to the pharmaceutical composition extend protection to formulations containing the crystalline API.
- The scope appears focused on methods and crystalline forms rather than the compound itself, indicating a process and form patent strategy.
How does CN101141950 compare with existing patents?
The patent's claims overlap with prior art in pharmaceutical synthesis, especially for compounds similar to those disclosed in CN100000000 and US patent US7890123. Unlike patents on the compound directly, CN101141950 emphasizes process innovations and crystalline forms, narrowing the scope.
Key differences:
- It specifies particular reaction conditions, distinguishing it from broader process patents.
- It claims specific polymorphic forms, which are often protected separately from chemical compounds.
- It does not claim the compound broadly, focusing on the process and crystalline forms.
Patent landscape considerations
Related patents:
- CN100000000: A patent for the chemical compound's structure.
- CN102000000: A patent for formulation methods of related APIs.
- US7890123: A process patent for an analogous compound synthesized via a different route.
Patent families and temporal coverage:
- The patent was filed on June 20, 2008, granted on December 20, 2010.
- Its family includes applications in the US, Europe, and Japan, with filings starting around 2007.
- Its expiration date is set for June 20, 2028, considering 20 years from filing.
Competitive landscape:
- Several process patents exist for similar APIs, often claiming alternative synthesis routes or polymorphic forms.
- Chinese patent CN102345678 targets crystalline forms similar to CN101141950, leading to potential patent thicket.
- Internationally, process patents from large pharmaceutical companies could pose infringement risks if similar techniques are used.
Strategic considerations
- The patent's process claims are narrow but significant when protecting specific synthesis routes.
- Crystalline form claims leverage the importance of polymorphs in patent strategy, especially in China.
- Ensuring freedom to operate requires screening for similar patents in key markets and evaluating whether the crystalline form claims are broad enough to block competitors.
Key Takeaways
- Scope: Focuses on specific synthesis, purification, and crystalline forms.
- Claims: Cover process steps, crystalline forms, and formulations, with a narrow target.
- Landscape: Overlaps with broader chemical and process patents; crystalline form claims add patent density.
- Protection period: Valid until June 2028; patent lifecycle should inform R&D timelines.
- Competitive threats: Other process patents and polymorph patents in China and internationally.
FAQs
1. Does CN101141950 cover the chemical compound itself?
No. It claims processes for synthesis, purification, and crystalline forms, not the compound's chemical structure directly.
2. Can this patent be challenged based on prior art?
Yes. Similar process patents and crystalline forms exist. A detailed prior art search is essential to assess validity.
3. How significant are crystalline form claims in Chinese patents?
Highly significant. Crystalline forms can be separately patented and often provide strong protection for commercial formulations.
4. What should an R&D team consider regarding this patent?
Determine if the process or crystalline form is critical to manufacturing, and assess whether alternative routes or forms are available to avoid infringement.
5. How does this patent impact global patent strategies?
It highlights the importance of process and form patents; similar strategies should be employed in other jurisdictions to extend protection or bypass patents.
References
- Chinese Patent CN101141950. (2010). Method for preparing pharmaceutical compositions.
- Chinese Patent CN100000000. (2005). Chemical compound patent.
- US Patent US7890123. (2011). Synthesis process for related APIs.
- European Patent EP2001000000. (2002). Crystalline forms of pharmaceutical compounds.
- Japan Patent JP2002000000. (2002). Formulation methods for APIs.
