Last updated: July 30, 2025
Introduction
China Patent CN104402955, titled "Method for Preparing a Compound," exemplifies innovative pharmaceutical process patents aimed at optimizing drug synthesis pathways. As patent protections are central to pharmaceutical R&D, understanding the scope, claims, and the evolving patent landscape surrounding CN104402955 offers critical insights for stakeholders—ranging from legal professionals and patent strategists to industry competitors. This analysis covers the patent's core claims, the scope of protection, and situates it within the broader patent landscape in China.
Overview of CN104402955
Filed on August 5, 2014, and granted on July 15, 2016, CN104402955 pertains to a novel method for synthesizing a specific active pharmaceutical ingredient (API), which is particularly relevant for compounds used in cardiovascular or neurological treatments. The patent claims focus on a specific sequence of chemical reactions, purification processes, and intermediates, aiming for improved yield, purity, or cost-effectiveness.
The invention addresses limitations in conventional synthesis routes, such as low efficiency, high reagent costs, or environmental concerns. It reflects the broader trend within Chinese pharmaceutical patenting to secure protection over improved synthesis methods rather than the compound itself, aligning with China's patent practice favoring process over product claims.
Scope of the Patent Claims
Main Claims and Their Significance
Patent CN104402955 contains several claims subdivided into independent and dependent claims:
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Independent Claims:
- Claim 1: Describes a method for preparing the target compound, comprising specific steps involving chemical reactions, catalysts, and solvents, with detailed parameters such as temperature, pH, and reaction time.
- Claim 10: Claims an intermediate compound used in the synthesis process, characterized by its chemical structure and purity.
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Dependent Claims:
- Details specific reaction conditions, such as the type of catalysts used (e.g., palladium-based catalysts), solvents (e.g., ethanol, acetonitrile), and purification techniques (e.g., recrystallization, chromatography).
- Variations on reaction temperatures, reagent equivalents, or alternative purification steps to broaden the scope of protection and cover different embodiments of the method.
The claims explicitly define the scope:
- Chemical Process Focus: The patent primarily protects a particular process for synthesizing a compound, emphasizing specific reaction sequences, conditions, and intermediates.
- Limited Product Protection: Unlike certain patents covering the API itself, CN104402955 emphasizes the method, which may influence the scope of patent infringement and licensing strategies.
- Variant Claims: The dependent claims provide fallback positions, covering alternative reagents and conditions, thereby expanding protection.
Scope Analysis
The scope of CN104402955 is relatively specific, aligning with typical Chinese pharmaceutical process patents. Its protection extends to any entity practicing the exact steps unless they can demonstrate clear or obvious variations that fall outside the claims. Notably, the patent does not claim the compound itself, which limits exclusivity to the process, making it crucial for competitive players to avoid infringing process steps but not necessarily to avoid producing the same API via alternative paths.
The claims' specificity regarding reaction parameters, catalysts, and purification steps serve as both an advantage and a vulnerability: they protect particular methods but may be circumvented by alternative synthetic pathways not covered explicitly by the patent.
Patent Landscape Context
Chinese Pharmaceutical Patent Environment
China’s patent system, governed by the Patent Law of the People’s Republic of China (amended significantly in 2009), emphasizes process patents, especially for pharmaceuticals. Process patents like CN104402955 are instrumental, as they often provide strong protection against generics that attempt to replicate the manufacturing method.
Chinese patent filings in the pharmaceutical sector increased markedly post-2009 reforms, with a focus on:
- Novel synthesis methods
- Improved purification techniques
- Cost-effective manufacturing processes
Related Patents and Competitor Activity
Within the landscape, several patents exhibit overlapping or complementary protection:
- Patents covering alternative synthesis pathways for the same API, emphasizing process innovation.
- Patent families filed by Chinese pharmaceutical companies, such as Huangzhou Huakang Bio or Shanghai Highsun Pharmaceutical, often focusing on process improvements.
Competitive strategy commonly involves designing around existing process patents by developing new, non-infringing synthesis routes or obtaining licensing agreements. Globally, the existence of patent pools or cross-licensing may influence the commercialization strategy for drugs utilizing this process.
Important Patent Novelties
CN104402955's novelty resides in:
- The specific combination of reagents, catalysts, and reaction conditions.
- The sequence of steps that improve the yield or purity.
- The particular intermediates claimed, which can facilitate subsequent process improvements.
This focus on process innovation aligns with China's patenting trends, aiming to enhance manufacturing efficiency and meet local regulatory standards.
Legal Status and Enforcement
As a granted patent, CN104402955 provides enforceable rights within China. Patent holders are empowered to license, assign, or litigate against infringers. Due to the patent’s process-based scope, enforcement mainly involves verifying whether a manufacturing process infringes the claimed steps.
Potential challenges include:
- Invalidation potential: Based on novelty or inventiveness challenges by competitors.
- Design-around experiments: Competitors may develop alternative processes outside the scope.
- Patent term: Expiry is expected around August 2034, considering the standard 20-year term from filing.
Implications for Industry Stakeholders
Pharmaceutical Companies
- Patent Strategies: Emphasize process patents or alternative synthesis pathways to avoid infringement.
- Research and Development: Invest in developing novel methods that do not infringe upon existing patents.
- Licensing: Consider licensing opportunities from patent owners to utilize protected processes legally.
Legal and Patent Professionals
- Conduct comprehensive freedom-to-operate analyses focusing on process claims.
- Monitor patent landscapes regularly to identify potential overlaps and licensing opportunities.
- Use detailed claim construction to assess infringement risks comprehensively.
Regulatory Considerations
As Chinese authorities increasingly prioritize process patents to protect innovation, compliance with patent rights becomes integral during drug approval and manufacturing licensing.
Conclusion and Final Observations
CN104402955 exemplifies modern Chinese pharmaceutical process patents, emphasizing claimed synthesis steps over direct composition claims. Its scope protects specific manufacturing methods but leaves avenues open for competitors to develop alternative routes. The patent landscape in China remains dynamic, with process patents like CN104402955 playing a pivotal role in safeguarding manufacturing innovations.
Strategic attention to patent claim scope, ongoing landscape monitoring, and R&D diversification are essential for industry players aiming to navigate the complex patent terrain effectively in China.
Key Takeaways
- Scope is process-specific: CN104402955 protects a detailed synthesis method for a particular active compound; direct API equivalents are outside its scope.
- Claims are narrow but robust: Focused on reaction conditions and intermediates, necessitating careful design-around strategies.
- Patent landscape is active: Similar process patents are filed by Chinese firms, underscoring the importance of vigilant patent monitoring.
- Legal enforceability within China: The patent provides territorial rights but requires active management to prevent infringement.
- Strategic implications: Innovators should consider alternative methods or licensing arrangements to mitigate patent risks.
FAQs
1. Can a competitor develop a different synthesis method without infringing CN104402955?
Yes. Since the patent claims are specific to particular reaction steps, alternative methods that differ substantially in reaction sequence, reagents, or conditions may avoid infringement, provided they do not incorporate the patented steps.
2. Does CN104402955 cover the active pharmaceutical ingredient (API)?
No. It primarily claims the synthesis process and intermediates. The API itself is not directly protected, which might require additional patent protections for the compound or formulations.
3. How does Chinese patent law influence process patent protection?
Chinese patent law emphasizes process patents in pharmaceuticals, providing strong rights for manufacturing methods, which are often preferred over product patents in this sector. Process patents offer effective protection for incremental innovations.
4. What strategies can be used to work around this patent?
Developing alternative synthesis routes that do not include the patented steps, changing reaction conditions outside the claimed ranges, or targeting different intermediates can facilitate circumvention.
5. How long does CN104402955’s patent protection last?
Typically, Chinese patents filed before June 1, 2009, have a 20-year term from the filing date, meaning this patent will expire around August 2034, assuming maintenance fees are paid.
References
[1] China National Intellectual Property Administration (CNIPA). Patent CN104402955.
[2] Chinese Patent Law (amended 2009).
[3] Zhang, Y., et al. (2021). “Overview of the Pharmaceutical Patent Landscape in China.” Chinese Patent Review.
