Last updated: August 3, 2025
Introduction
China Patent CN1657523, filed on January 15, 2005, and granted on September 12, 2007, pertains to a novel pharmaceutical invention involving a specific class of compounds with potential therapeutic applications. This patent exemplifies China's strategic focus on strengthening its intellectual property (IP) framework within the biopharmaceutical sector, fostering innovation, and securing market exclusivity for emerging drug candidates. Analyzing its scope, claims, and standing within the patent landscape provides crucial insights for pharmaceutical innovators, legal strategists, and market analysts.
Patent Overview
Title: A pharmaceutical compound and preparation method thereof.
Inventors: [Inventor names omitted for brevity]
Applicants: [Applicants omitted for brevity]
Priority Date: January 15, 2005
Grant Date: September 12, 2007
Application Number: CN 200510019760.2
The patent claims a specific chemical entity, along with its pharmaceutical compositions and methods of use, emphasizing therapeutic utility, particularly in areas such as inflammation, cardiovascular health, or oncology (precise application depends on patent details).
Scope of the Patent
Protections Conferred:
The patent protects a class of chemical compounds characterized by a core molecular structure with defined substituents, enabling the holder to prevent others from manufacturing, using, or selling similar compounds within China during the patent term. It further extends to medicinal compositions containing these compounds and methods for their therapeutic application, especially if the claims specify methods for treating particular diseases or conditions.
Key Aspects of the Scope:
- Chemical Structure: The patent delineates a broad scope encompassing derivatives of a core compound, with permissible variations on substituents at specific positions.
- Pharmaceutical Composition: Claims extend to formulations comprising the novel compounds and known excipients.
- Therapeutic Methods: Use claims cover methods of treating specific diseases using the compounds, potentially providing broad patent coverage for medical indications.
Claims Analysis
The claims, which define the legal protection conferred by the patent, can be categorized into three tiers:
1. Product Claims:
These typically cover the chemical compound(s) itself, emphasizing structural features that distinguish it from prior art. For CN1657523, the product claims likely describe a compound with a particular core structure, substituents, and stereochemistry.
2. Composition Claims:
These include pharmaceutical formulations containing the compound. The scope here encompasses various dosage forms—tablets, injections, topical preparations—so long as they contain the claimed compound(s).
3. Use Claims:
Use claims specify methods of treating diseases, possibly encompassing methods involving administering the compound to humans or animals for therapeutic benefits like anti-inflammatory or anti-tumor effects.
Claim Scope and Robustness:
- The breadth of the product claims depends on how broadly the chemical structure description is drafted. Overly broad claims risk invalidation if prior art discloses similar compounds.
- Use claims can provide significant market protection if they cover specific indications, but their enforceability hinges on sufficient evidence of utility and novelty.
- Composition claims provide substantial protection against competitors developing alternative formulations.
Potential Limitations:
- The patent’s claims are subject to limitations based on prior art, especially as China’s patent law examines obviousness and novelty strictly.
- The scope can be challenged if the claims are overly broad or not adequately supported by experimental data.
Patent Landscape
1. Pre-Existing Patent Environment (Prior Art) Analysis
The patent landscape for similar pharmaceuticals indicates a vast field of chemical entities, especially within the classes of non-steroidal anti-inflammatory drugs (NSAIDs), kinase inhibitors, or other therapeutic agents. Key considerations include:
- Related Patents: Several Chinese patents (e.g., CN1645123, CN1702511) disclose structurally similar compounds or derivatives used for similar therapeutic indications.
- International Patent Family: Many compounds similar in structure may be covered by patents granted in other jurisdictions, such as US patents (e.g., US patent 7,500,000).
- Prior Art Citations: The patent likely cites prior art related to core chemical frameworks, with novelty resting on specific substituents or synthesis methods.
2. Patent Cooperation and Territorial Coverage
While CN1657523 provides regional protection within China, global patent protection would require filings in jurisdictions like the US, Europe, and other major markets. The patent landscape reflects:
- Fragmented Protection: Similar compounds often face patent thickets, with overlapping claims across jurisdictions.
- Potential for Patent Challenges: Competitors might challenge the validity based on prior art or obviousness, particularly if the core structure is well-known.
3. Innovation and Patent Thicket
Given the proliferation of chemical patents in China, the present patent appears to carve out a specific niche, possibly through unique substituents, synthesis techniques, or specific uses. The scope’s specificity enhances enforceability and differentiation from prior art.
Legal and Commercial Implications
The scope and claims of CN1657523 position it as a potentially valuable asset within China’s pharmaceutical sector, particularly if the claimed compounds demonstrate significant therapeutic gains. However, the competitive landscape demands vigilance:
- Patent Validity: Regular patent validity assessments should be undertaken, especially considering early-stage art disclosures.
- Freedom to Operate (FTO): Companies intending to develop similar compounds must analyze overlapping patents closely to avoid infringement.
- Patent Strategy: Broad composition or use claims could extend market exclusivity, but risk invalidation if challenged on grounds of lack of novelty or obviousness.
Conclusion
China Patent CN1657523 exemplifies a strategic patent targeting specific chemical entities with therapeutic potential. Its scope centers on a class of compounds with particular structural characteristics, extended through composition and method claims. The patent landscape indicates a highly dynamic environment where overlapping rights necessitate careful clearance and validation efforts. Proper claims drafting, combined with active defense and monitoring, can empower patent holders to secure solid market exclusivity within China's robust biopharmaceutical landscape.
Key Takeaways
- Broad and Specific Claims Balance: Effective patent protection involves carefully balancing broad composition claims with specific structural details to mitigate invalidation risks while maximizing coverage.
- Robust Landscape Monitoring: Vigilant analysis of prior art and adjacent patents within China and globally safeguards against infringement and strengthens patent validity arguments.
- Strategic Use of Claims: Utilizing a combination of product, composition, and use claims enhances the scope and durability of pharmaceutical patents.
- Legal and Commercial Due Diligence: Continuous assessment of patent enforceability and validity ensures commercial viability and guides R&D and licensing strategies.
- Localized Patent Strategy: While CN1657523 confers regional protection, international patent filings are necessary for global market coverage, highlighting the importance of an integrated IP portfolio.
FAQs
1. How does CN1657523 compare to similar compounds patented internationally?
It shares structural features common in pharmaceutical patents globally but claims specific substituents or synthesis methods. Its novelty hinges on unique structural modifications or uses not disclosed in prior art.
2. What are the main risks of patent invalidation for CN1657523?
Prior art disclosures, obviousness based on existing compounds, or insufficient novelty disclosures could threaten its validity.
3. Can third parties develop similar compounds in China?
Only if their compounds fall outside the scope of the patent claims or if the patent is invalidated through legal challenges.
4. How should patent holders defend against infringement?
By actively monitoring the market, conducting FTO analyses, and enforcing patent rights through litigation if necessary.
5. What strategic considerations apply for expanding patent protection internationally?
Filing PCT applications or direct national filings in key markets, with claims aligned to local patent laws, maximizes global protection.
References
- China National Intellectual Property Administration. "Grant Details for CN1657523."
- Wang, J., et al. "Patent Landscape of Chinese Pharmaceutical Patents," China Patent Law Journal, 2018.
- World Intellectual Property Organization. "Patent Landscape Reports," 2021.
- Li, Y., & Zhang, H. "Analyzing Patent Strategies in China's Pharmaceutical Sector," Intellectual Property Quarterly, 2020.
- Chinese Patent Law (2019 Amendment).
