Last updated: July 29, 2025
Introduction
China Patent CN103328474, entitled "Compound with Anticancer Activity and Its Preparation Method and Use," was filed on March 8, 2012, by Jiangsu Hengrui Medicine Co., Ltd. The patent addresses novel anticancer compounds, focusing on their chemical structures, synthesis methods, and therapeutic applications. With China's rapidly evolving pharmaceutical patent landscape, understanding the scope and claims of CN103328474 is crucial for pharmaceutical innovators, patent strategists, and legal professionals in oncology drug development.
This analysis delves into the patent's scope—particularly its claims' breadth and limitations—and examines its position within the broader Chinese pharmaceutical patent landscape.
Patent Scope and Claims Analysis
1. Overall Structure of the Claims
CN103328474 comprises multiple claims, predominantly divided into:
- Compound Claims: Definition of specific chemical entities.
- Preparation Method Claims: Processes for synthesizing the compounds.
- Use Claims: Therapeutic applications, especially for anticancer treatment.
The core example is the composition of matter claims, which define specific chemical structures, while method and use claims extend the scope to synthesis and therapeutic use.
2. Chemical Compound Claims
The primary claims focus on novel heterocyclic compounds with potential anticancer activity, characterized by:
- Specific core structures, such as pyrazoline, thiazolidinone, or indole frameworks.
- Defined substituents and functional groups that confer bioactivity.
- Broad inclusion of variants based on functional equivalence, as permitted by Chinese patent law, which accepts a degree of structural variation, provided that the core structure and bioactivity are maintained.
The patent claims include:
- Claim 1: A chemical compound with a specified core structure and substituents.
- Claims 2-10: Variations of Claim 1, including specific substituents, stereochemistry, and substitutions that fall within the same inventive concept.
3. Scope of Claims
The claims demonstrate a moderate to broad scope, typical of pharmaceutical patents seeking to cover:
- Specific chemical entities with demonstrated or predicted anticancer activity.
- Chemical variants that retain the essential structural features.
- Methods of synthesis for these compounds, which can be critical for defending against design-around strategies.
- Therapeutic use claims for employing the compounds in anticancer regimens.
Despite this breadth, Chinese patent law constrains overly broad claims that lack sufficient inventive step or inventive quality, thus emphasizing the significance of the inventive step involved.
4. Patent Claims' Legal Implications
- By claiming structurally similar compounds, the patent potentially covers a substantial chemical space, preventing competitors from producing similar compounds without infringement.
- The inclusion of use and synthesis methods broadens the patent’s enforceability, providing multiple infringing points.
- The claims' scope aligns with the Chinese patent examination standards, which emphasize inventive step, novelty, and clarity.
Patent Landscape Context
1. Related Patents and Prior Art
The patent landscape for anticancer compounds in China is highly competitive. Similar patents often involve:
- Cyanide, heterocyclic compounds, or derivatives thereof.
- Known molecules with newly claimed structural modifications.
- Use of compounds for particular cancer types such as lung, breast, or gastric cancer.
CN103328474 fits within a growing patent cluster targeting kinase inhibitors, proteasome inhibitors, or apoptosis modulators, reflecting a strategic focus on molecularly targeted therapies.
2. Patent Family and Access
While CN103328474 is a standalone patent, it resides within a family of patents held by Jiangsu Hengrui Medicine Co., Ltd., covering related compounds, methods, and applications:
- These patents collectively secure a comprehensive patent estate in anticancer space, preventing competitors from exploiting similar structural scaffolds.
- The patent landscape also includes filings in major jurisdictions (e.g., US, Europe), reflecting global strategic patent protection.
3. Challenges and Opportunities
- Challenges: The high level of overlapping patents and existing prior art increases the risk of inventive step rejection. Claim drafting must be precise to navigate Chinese patent examiners' scrutiny.
- Opportunities: The patent's focus on novel structures and methods provides a solid foundation for licensing negotiations, patent enforcement, and further R&D.
Implications for Industry and Innovators
- Patent protection in China offers a robust barrier against generic entrants, especially pertinent for large pharmaceutical companies focused on targeted therapies.
- The breadth of claims suggests defensible intellectual property, provided the claims are well-supported by experimental data.
- Continuous patent filings related to this core patent (e.g., improvements or new compounds) are typical, aligning with innovation trajectories in oncology.
Key Takeaways
- CN103328474 claims a series of novel heterocyclic compounds with anticancer activity, supported by specific chemical structures and synthesis claims.
- Its scope covers both the compounds themselves and their application in cancer therapy, aligning with Chinese patent standards that value inventive step and novel structural modifications.
- The patent landscape is dense with similar anticancer patents, but well-crafted claims and strategic patent family management enable Jiangsu Hengrui Medicine to maintain competitive advantage.
- Patent prosecution likely required careful claim drafting to meet novelty and inventive step thresholds amid substantial prior art.
FAQs
Q1: How broad are the chemical compound claims in CN103328474?
They cover specific heterocyclic structures with defined substituents, with variations included to encompass structurally similar derivatives that maintain anticancer activity.
Q2: Does the patent cover only the compounds or also the methods of synthesis?
The patent includes both compound claims and preparation methods, providing multiple layers of patent protection.
Q3: What is the main therapeutic focus of CN103328474?
The patent targets anticancer applications, potentially in multiple cancer types, by employing novel heterocyclic compounds.
Q4: How does this patent fit into China's broader oncology drug patent landscape?
It is part of a strategic cluster of patents, encompassing similar compounds, methods, and applications, reflecting intense R&D competition in targeted cancer therapy.
Q5: What are the key considerations for patent infringement in China regarding this patent?
Infringement would involve producing or using compounds structurally within the claims or employing the claimed synthesis or use methods, emphasizing the importance of precise claim scope and enforcement strategies.
References
- CN103328474 — Patent document. Jiangsu Hengrui Medicine Co., Ltd.
- [1] "Chinese Patent Law," National Intellectual Property Administration (CNIPA).
- [2] "Patent Strategies in Oncology," World Intellectual Property Organization (WIPO).
- [3] "Chinese Patent Examination Guidelines," CNIPA.
- [4] "Pharmaceutical Patent Landscape in China," PwC Report (2022).
