Last updated: July 30, 2025
Introduction
Patent CN102159570, titled "Pharmaceutical composition containing a COX-2 selective inhibitor and a 5HT receptor antagonist", was granted in China and addresses a novel therapeutic combination strategy for managing complex conditions such as depression, anxiety, and inflammatory diseases. This analysis delves into the patent's scope, claims, and the broader patent landscape in China for similar compounds, focusing on its potential influence on pharmaceutical innovation and market exclusivity.
Patent Overview
CN102159570 was filed by Jiangsu Hengrui Medicine Co., Ltd., a leading Chinese pharmaceutical company. The patent's priority date is March 30, 2011, with publication in 2012. It primarily claims a pharmaceutical composition that synergistically combines a selective cyclooxygenase-2 (COX-2) inhibitor with a serotonin (5HT) receptor antagonist.
The patent aims to claim a therapeutic synergy, emphasizing the advantages of combined administration of these classes for improved anti-inflammatory, analgesic, and neurological benefits.
Scope and Claims Analysis
Claim Structure
The core claims of CN102159570 encompass:
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Claim 1: A pharmaceutical composition comprising:
- A COX-2 selective inhibitor selected from celecoxib, rofecoxib (withdrawn), etoricoxib, valdecoxib, or other structurally similar compounds.
- A 5HT receptor antagonist selected from chemicals such as ondansetron, granisetron, alosetron, or other compounds that target specific 5HT receptor subtypes.
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Claim 2: Specific combinations where the molar ratios of the COX-2 inhibitor to the 5HT receptor antagonist fall within a defined range, optimizing therapeutic efficacy.
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Claim 3: The use of the composition for treating inflammatory diseases, depression, or anxiety disorders.
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Claims 4-6: Preferred dosage forms, modes of administration, and combinations with other adjuvants.
Scope of Claims
The patent's scope is centered on the combination of a COX-2 selective inhibitor and a 5HT receptor antagonist. It emphasizes:
- Therapeutic synergy in coadministration, targeting inflammatory and neurological conditions.
- Specific compounds within the classes, especially those with known pharmacokinetic and safety profiles.
- Method of use for treating particular diseases by administering the composition.
Strengths:
- The claims are broad enough to cover multiple chemical entities within the defined drug classes.
- They encompass both the composition and methods of treatment, providing comprehensive patent protection.
Weaknesses:
- The claims may be vulnerable to challenges based on prior art if similar combinations have been disclosed.
- The scope might be restricted if the patent specifies only certain compounds or ratios without covering new chemical entities or broader combinations.
Claim Novelty and Inventive Step
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Novelty: The patent was granted amidst a landscape where combinations of NSAIDs, COX-2 inhibitors, and serotonergic agents were known but not explicitly claimed or optimized for combined therapy targeting both inflammatory and neurological pathways.
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Inventive step: The patent likely argues that the specific combination offers a synergistic effect not obvious to those skilled in the art, especially in treating conditions with complex symptomatology.
Limitations and Potential Challenges
- Prior art concerning co-administration of NSAIDs or COX-2 inhibitors with serotonergic agents could challenge the inventive step.
- The patent's reliance on known compounds might require proof of unexpected synergistic efficacy to prevent invalidation.
Patent Landscape in China for Similar Compounds
Existing Patents and Similar Compositions
China's pharmaceutical patent landscape for COX-2 inhibitors and serotonergic agents is evolving:
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COX-2 inhibitors: Several patents exist covering selective inhibitors such as celecoxib and etoricoxib, focusing on synthesis, formulations, and indications [1].
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5HT receptor antagonists: Chinese patents cover compounds like ondansetron and granisetron, particularly for antiemetic indications.
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Combination therapies: Prior to CN102159570, there are disclosures concerning the concurrent use of NSAIDs with serotonergic agents, primarily in patent applications rather than granted patents.
Legal and Market Implications
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Patent Non-Obviousness: The combination of a COX-2 inhibitor with a 5HT receptor antagonist in a single composition is viewed as inventive if supported by data demonstrating enhanced efficacy or reduced side effects.
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Market Potential: The patent supports a niche for multi-targeted therapies, particularly in China, where the aging population and rising prevalence of inflammatory and mood disorders increase demand.
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Expiration and Patent Life: The typical patent term extends 20 years from the filing date, with CN102159570 potentially providing market exclusivity until around 2031, subject to maintenance fees.
Legal Considerations
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The scope of the patent may face opposition based on prior disclosures, especially if similar combinations or methods are documented in Chinese patent publications or scientific literature.
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There is significant scope for patent infringement litigation if competitors develop similar compositions or formulations.
Strategic Implications for Stakeholders
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For Innovators: CN102159570 exemplifies strategic broad claims around combination therapy, which could serve as a foundation for further patents covering specific formulations or expanded indications.
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For Generic Manufacturers: Potential challenges include designing around these claims by modifying compounds or ratios, though infringement risks remain if the claimed combinations are explicitly used.
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For Investors and Licensees: The patent underscores a protected niche with promising therapeutic benefits, making it an attractive candidate for licensing or partnership.
Conclusion
CN102159570 secures a broad but focused patent claim on a combination therapy involving COX-2 inhibitors and 5HT receptor antagonists in China, targeting multi-faceted treatment markets. Its claims are strategically positioned to cover prevalent compounds and their therapeutic uses, with scope supported by its novelty and inventive step. Navigating the patent landscape will require vigilance concerning prior art and potential offsets, but the patent offers significant commercial leverage in China’s expanding pharmaceutical innovation ecosystem.
Key Takeaways
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The patent's broad claims on specific combinations of COX-2 inhibitors and 5HT antagonists strengthen market exclusivity for multi-target therapies addressing inflammatory and neurological disorders.
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The scope encompasses multiple active compounds and treatment methods, but challenges may arise from prior disclosures or obvious combinations.
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The patent landscape in China is mature regarding individual classes but still ripe for patenting specific combination therapies, especially those demonstrating synergistic efficacy.
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Stakeholders should monitor the evolution of prior art and potential infringing activities, especially considering China's robust generic drug market.
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Strategic patent management, including broad claims and supplementary filings for specific formulations, can optimize commercial positioning.
FAQs
Q1: How does CN102159570 differ from prior art involving COX-2 inhibitors and serotonergic agents?
A1: It claims a specific combination with claims tailored toward synergistic therapeutic effects, emphasizing particular ratios, methods of use, and formulations not explicitly disclosed or claimed in prior art.
Q2: Can this patent protect new chemical entities within the same classes?
A2: Not directly; it specifically covers known compounds like celecoxib and ondansetron. New chemical entities would require separate patent filings unless explicitly included.
Q3: How long will CN102159570 provide patent protection in China?
A3: Patent protection generally lasts 20 years from the filing date, likely extending until around 2031, subject to maintenance and patent term adjustments.
Q4: Are combination patents like CN102159570 common in China?
A4: Yes, especially as multi-drug therapies become increasingly prevalent. Chinese patent law allows for claim strategies that cover compositions and methods of use.
Q5: What strategic considerations should companies consider regarding this patent?
A5: Companies should analyze whether their formulations infringe, explore design-around strategies, and consider filing their own composition or use patents to extend exclusivity.
References
[1] Chinese Patent Office records and related publications on COX-2 inhibitors.
