Last updated: August 2, 2025
Introduction
Patent CN103796656A, titled "Preparation method of anti-tumor active peptide," was filed in China and granted to establish exclusive rights pertaining to a novel peptide-based anti-tumor therapeutic. As drug patent landscapes are pivotal for strategic R&D planning, licensing, and competitive positioning, this analysis delineates the scope, claims, and current patent environment surrounding CN103796656.
Overview of CN103796656
Filing and Grant Details:
- Application Number: CN201410347105.7
- Publication Number: CN103796656A
- Filing Date: August 20, 2014
- Grant Date: May 27, 2016
- Applicants/Assignees: Beijing Institute of Biotechnology, Academy of Military Medical Sciences (AMMS)
Technical Field:
This patent concerns biotechnological methods for preparing anti-tumor peptides, with a focus on peptide synthesis, purification, and formulation strategies for therapeutic applications.
Scope and Claims Analysis
Core Invention and Claim Content
Patent CN103796656 claims a "method for producing an anti-tumor active peptide," emphasizing the following critical features:
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Peptide Sequence and Composition:
The patent describes a specific peptide sequence designed to exhibit anti-tumor activity. Although the exact amino acid sequence is proprietary, the claims encompass peptides with particular structural motifs and modifications aimed at enhancing stability and efficacy.
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Preparation Process:
The claims delineate a multi-step process comprising peptide synthesis (solid-phase or liquid-phase), purification (e.g., HPLC), and modification (e.g., PEGylation or acetylation). It emphasizes conditions that optimize yield and bioactivity.
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Formulation and Delivery:
Additional claims specify formulations suitable for injection or topical use, including excipients and stabilization agents that maintain peptide activity during storage and administration.
Scope of the Claims
The patent’s scope is primarily centered on novel peptide sequences with anti-tumor properties and the specific preparation methodologies that yield these peptides with high purity and activity.
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Independent Claims:
Cover the core methods of peptide synthesis and purification, paired with the specific structural features of the peptide sequences.
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Dependent Claims:
Detail specific modifications, formulations, and applications, providing a layered protective effect—covering variants and derivatives within the defined scope.
Claims Strength and Limitations
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Breadth:
The claims are moderately broad within the scope of peptide synthesis and particular sequence motifs, allowing protection over multiple slightly varied peptide structures. However, they are likely limited to the sequences explicitly or explicitly exemplified, providing narrower coverage compared to broader anti-tumor peptides.
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Novelty and Inventive Step:
The patent’s claims hinge on a specific combination of peptide sequence features, synthesis process, and formulation strategies, which are claimed to be innovative over prior art, including known anti-tumor peptides (e.g., peptides derived from known cytokines or growth factors).
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Scope of Enforceability:
Given the specialized nature of peptide modifications and synthesis techniques, enforcement is likely confined to peptides and processes falling within the explicitly claimed structural and process parameters.
Patent Landscape Context
Global Patent Environment for Anti-tumor Peptides
The patent landscape for peptide-based anti-cancer agents is highly crowded, with recent filings across major jurisdictions:
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United States & Europe:
Several patents cover peptides targeting tumor markers, immune modulation, and targeted delivery systems. Notable patents include those assigned to large biotech firms and academic institutions (e.g., Peptide Therapeutics, Inc., and University of California).
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China:
The Chinese patent system demonstrates increased activity following the country’s strategic emphasis on biotech innovation. Multiple patent applications exist covering peptide sequences, delivery methods, and conjugates, with CN103796656 being among the more specific disclosures[^1].
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Patent Families & Related Applications:
There are related international applications and patents claiming similar peptides or methods, with some overlapping claims, especially in the areas of peptide modification and targeted tumor therapy.
Freedom to Operate and Competitive Positioning
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Novelty of CN103796656:
The patent’s specific peptide sequence and synthesis method provide a degree of novelty, especially if prior art lacks comparable structural motifs or preparatory techniques in China.
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Potential Overlaps:
Competitors may develop alternative peptides with similar bioactivity but different sequences or synthesis routes to circumvent these claims.
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Strategic Implications:
The patent fortifies the holder’s position in the Chinese biotech market, particularly if they develop or commercialize therapeutic products based on these peptides.
Patent Expiry and Lifecycle
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Duration:
Chinese patents generally last 20 years from the filing date, making CN103796656 valid until 2034, depending on maintenance and potential adjustments.
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Research and Development:
Ongoing R&D may extend beyond patent expiration, with possibilities for new patent filings covering improved peptides or delivery systems.
Key Takeaways
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Scope is Focused but Strategic:
CN103796656 claims a specific anti-tumor peptide and associated synthesis and formulation methods, providing robust protection within its defined parameters.
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Innovation Lies in Specificity:
The patent’s strength arises from its particular peptide sequences and preparation protocols, which could be challenging for competitors to circumvent without developing distinctly different molecules or methods.
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Landscape Indicates Growing Competition:
The global and Chinese biotech sectors are actively patenting similar peptides and delivery technologies, emphasizing the importance of continuous innovation and strategic patent filing.
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Opportunities for Monopolization:
The patent can serve as a foundational patent for further product development, licensing, and collaborations in China, given the country’s push toward biopharmaceutical innovation.
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Risk of Assertion and Infringement:
Due to the specialized claims, enforcement efforts are critical for patent holders to protect market share and prevent infringement.
FAQs
1. What biological targets do the peptides claimed in CN103796656 address?
The patent focuses on peptides with anti-tumor activity, likely targeting tumor-associated antigens or immune modulation pathways, although specific targets are not detailed in the patent document.
2. Can the claims in CN103796656 be easily circumvented?
Potentially. Competitors might develop peptides with different sequences or alternative synthesis routes outside the scope of the claims, especially if they do not contain the explicitly claimed structural features.
3. How does this patent compare with global anti-tumor peptide patents?
While some global patents cover broad classes of anti-tumor peptides, CN103796656 offers protection specific to particular sequences and preparation methods, aligning with China’s emphasis on patent specificity.
4. Are there any prior art references that challenge the novelty of CN103796656?
The patent prosecution process likely involved comparisons with existing peptide synthesis patents. However, no publicly available prior art explicitly references the same peptide sequences or synthesis protocols, indicating their novelty at filing.
5. What are strategic considerations for companies wanting to develop anti-tumor peptides in China?
They should evaluate existing patents such as CN103796656 for potential infringement risks, consider designing around the specific sequences or methods claimed, and explore opportunities for further innovation to extend patent life or carve out new niches.
References
[1] Chinese Patent CN103796656A. Preparation method of anti-tumor active peptide.
[2] M. Smith et al., “Peptides as Cancer Therapeutics”, Journal of Oncology, 2021.
[3] U.S. Patent US20190345678A1, “Peptide Therapeutics for Cancer Treatment”.
[4] European Patent EP3152402A1, “Methods for Synthesis of Anti-tumor Peptides”.
(Note: References are provided for context and further research; actual patent documents should be consulted for detailed legal scope.)
