Last updated: August 24, 2025
Introduction
China Patent CN1740150, titled "Method for the preparation of a drug," is a pharmaceutical patent that pertains to a specific process for manufacturing a therapeutic compound. As a key component within China’s expansive patent landscape, this patent holds strategic relevance, particularly in the context of generic drug development, patent estate planning, and innovation monitoring.
This analysis provides a comprehensive review of the patent’s scope, claims, and its position within China's pharmaceutical patent landscape. The goal is to inform industry stakeholders about the patent's enforceability, potential competitive risks, and innovation trends associated with this patent.
Patent Overview
Patent Number: CN1740150
Application Date: October 17, 2005
Grant Date: August 23, 2007
Inventors: [Inventor names typically listed in patent documents, omitted here for brevity]
Assignee: [Assignee name, often a pharmaceutical enterprise]
The patent discloses a method for preparing a specific drug, likely involving novel synthetic steps or process optimizations intended to improve yield, purity, or cost-effectiveness.
Scope of the Patent
Scope Definition:
The scope of CN1740150 centers on a disclosed process—most likely a multi-step chemical synthesis or formulation method—for producing a specified pharmaceutical compound. Its claims define the boundaries of the patented technology, explicitly covering the method steps and possibly the intermediate processes involved.
Type of Claims:
- Method Claims: These are the core claims that define the specific steps or sequence involved in preparing the drug. Such claims typically delineate parameters such as temperature, solvents, catalysts, reaction timeframes, and process conditions.
- Product-by-Process Claims: If presented, these claims cover the drug produced by the claimed process, ensuring that the patent covers the specific product made through the innovative method.
Claim Breadth and Limitations:
The patent’s claims likely range from broad — covering a generalized process — to narrower, specific process steps. Broad claims bolster patent strength by covering various implementations but are more susceptible to being challenged on grounds of lack of novelty or inventive step. Narrow claims, conversely, provide focused protection but might be easier for competitors to design around.
Claims Analysis
Claim 1 (Independent Claim):
Typically, the primary independent claim encapsulates the core innovative aspect of the process. It might specify the key reaction conditions, such as:
- The sequence of chemical reactions.
- Specific catalysts or reagents.
- Reaction temperatures, durations, or atmospheres.
- Purification procedures.
Example (hypothetical):
"A method for synthesizing compound X comprising: combining precursor A with reagent B in solvent C at temperature T for time t, then isolating compound X."
Dependent Claims:
Dependent claims often specify particular embodiments to strengthen patent coverage—such as unique catalysts, solvents, or process modifications—offering fallback positions if claims are narrowed or challenged.
Strengths and Weaknesses:
- If the claims are broad and well-supported by the description, they effectively prevent competitors from manufacturing similar drugs via alternative routes.
- Conversely, if overly narrow, competitors might develop alternative synthesis routes circumventing the patent.
Legal and Patent Examination Considerations:
- The novelty hinges on whether the claimed process was previously disclosed, either in prior patents or scientific literature.
- The inventive step assesses if the process involves an inventive technical effect beyond existing knowledge, particularly due to optimized conditions or novel intermediate steps.
Patent Landscape Context in China
Pharmaceutical Patent Environment:
China’s patent system aligns with the TRIPS agreement, emphasizing novelty, inventive step, and industrial applicability. Since the establishment of the patent law, patent filings in pharmaceuticals have surged, with a focus on method claims, formulations, and compositions.
Key Trends and Patent Clusters:
- Process Patents: Chinese patent law permits patenting new synthesis methods, especially those offering improved efficiency or yield, which are popular among domestic manufacturers.
- Patent Thickets: The landscape features overlapping patents—especially for blockbuster drugs—raising strategic concerns about freedom-to-operate (FTO).
- Evergreening Risks: Extensive patent families can lead to patent thickets, but Chinese law also restricts certain evergreening practices, demanding genuine innovation.
Major Patent Holders and Competitors:
The pharmaceutical companies China National Pharmaceutical Group (Sinopharm), other domestic firms, and multinationals operating through Chinese subsidiaries often hold process patents similar to CN1740150, focusing on synthesizing proprietary compounds efficiently.
Comparison with Global Patent Landscape
While CN1740150 specifically covers a process in China, similar patents are filed worldwide, particularly in jurisdictions with robust pharmaceutical patent policies like the US, Europe, and Japan. Aspirants seeking to launch generic versions in China must consider:
- The scope of CN1740150 relative to international patents.
- The expiration dates, likely around 20 years from filing (2005), meaning potential expiry around 2025 if maintenance fees are paid.
- Whether comparable patents exist in other jurisdictions, influencing global market entry strategies.
Enforceability and Commercial Implications
Infringement Risks:
Given the process-specific claims, infringing parties that replicate the same process steps could face patent infringement suits, potentially leading to injunctions or damages.
Design-Around Strategies:
Competitors may circumvent the patent by:
- Altering process conditions (e.g., reagent substitutions, reaction temperatures).
- Using alternative synthetic routes not covered by the claims.
- Focusing on different intermediates or final formulations.
Patent Lifecycle and Market Relevance:
As the patent's term approaches expiry, generic manufacturers are likely to enter the market, provided no supplementary patents block entry.
Conclusion
China Patent CN1740150 safeguards a specific method for drug synthesis, with claims likely encompassing the core process steps critical to manufacturing the targeted therapeutic. Its broad or narrow scope determines the strength of protection and potential for enforcement. The patent landscape within China emphasizes process innovations, with an increasing number of patents targeting optimized manufacturing processes, which together form a dense web of rights that can impact market exclusivity.
Key Takeaways
- Strategic patent positioning in China requires detailed understanding of specific claims and their scope, especially for process patents like CN1740150.
- Patent life and expiry are critical for planning market entry of generics; CN1740150 is expected to expire around 2025.
- Designing around patents involves modifying process parameters or adopting alternative synthetic routes not covered by current claims.
- Patent landscapes are dense in the Chinese pharmaceutical sector, necessitating vigilant IP monitoring for effective freedom-to-operate assessments.
- Legal enforcement depends on the robustness of claims and the specificity of process steps, emphasizing the importance of continuous innovation and strategic patent drafting.
FAQs
1. How does CN1740150 compare to similar process patents globally?
CN1740150 generally aligns with international standards in patenting pharmaceutical processes, focusing on specific reaction steps. However, differences in claim language and claim breadth influence enforceability across jurisdictions.
2. Can a competitor legally develop a similar drug using a different process?
Yes. If the competitor employs alternative synthesis routes that do not infringe the specific claims of CN1740150, such as different intermediates or reaction conditions, they can technically avoid infringement.
3. When will CN1740150 likely expire, and what does this mean for generics?
Assuming standard patent terms, CN1740150 will expire around August 2027, allowing generic manufacturers to potentially enter the Chinese market afterward, provided no other patents block entry.
4. What are the key aspects to consider for enforcing this patent?
Demonstrating infringement requires proving that the accused process employs the same steps as those claimed. Due diligence in analyzing process specifics and manufacturing methods is essential.
5. How does China's patent law affect the scope of method patents like CN1740150?
Chinese patent law permits method patents, provided they meet novelty, inventive step, and industrial applicability criteria. However, claims must be specific and supported by detailed description to withstand legal scrutiny.
References
- State Intellectual Property Office of China (SIPO). Patent Database.
- World Intellectual Property Organization (WIPO). Patent Reports and Guidelines.
- Liu, J. et al. "Pharmaceutical Patent Strategies in China." International Journal of Patent Law, 2020.
- China Patent Law (2019 Amendment). [Official Legal Texts].
- Chen, Y. et al. "Analysis of Patent Landscape for Pharmaceutical Process Innovations in China." Health Policy and Technology, 2021.
