Last updated: February 21, 2026
What Does Patent CN103957888 Cover and How Broad Are Its Claims?
Patent CN103957888, filed by Shanghai Henlius Biotech, Inc. and granted in 2015, claims a monoclonal antibody composition targeting human epidermal growth factor receptor 2 (HER2). The patent primarily protects a specific antibody structure, its methods of production, and uses in treatment.
Scope of the Patent
Claims Overview
The patent contains 16 claims, with main emphasis on:
- A monoclonal antibody or fragment thereof with specific variable region sequences.
- The antibody's specificity for HER2.
- Methods of producing the antibody.
- Use of the antibody in HER2-positive cancers.
Key Claims
- Claim 1: Monoclonal antibody with the amino acid sequences of the variable heavy and light chains defined in the patent, capable of binding HER2.
- Claims 2–4: Variants with specific modifications or fragments maintaining HER2 binding.
- Claims 5–8: Methods for producing the antibody via recombinant DNA techniques.
- Claims 9–12: Use in treating HER2-positive cancers.
- Claims 13–16: Pharmaceutical compositions containing the antibody.
Patent Scope
The claims focus on a specific antibody sequence, closely aligned with trastuzumab (Herceptin), but with distinct sequence variations, establishing a narrow or medium scope around particular antibody variants and production techniques.
How Does the Patent Landscape Look for HER2-Targeted Antibodies in China?
Major Patent Holders
- Shanghai Henlius Biotech: Claims ownership of CN103957888, with subsequent patents expanding on their antibody variants.
- Existing Biosimilar Developers: Companies like BeiGene, Zai Lab, and Hansoh Pharma have filed patents relating to HER2 antibodies, some overlapping in target indications.
Key Patents and Similar Patents
| Patent Number |
Holder |
Filing Year |
Title / Focus |
Scope |
| CN103957888 |
Henlius |
2014 |
HER2-specific monoclonal antibody |
Sequence-specific antibody similar to trastuzumab |
| CN106413157 |
BeiGene |
2016 |
Bi-specific HER2 antibodies |
Broader scope including bi-specifics |
| CN106562679 |
Zai Lab |
2017 |
HER2 antibody conjugates |
Focus on antibody-drug conjugates (ADCs) |
The Chinese patent landscape concerning HER2 antibodies shows competitive activity, especially in biosimilar development. Many patents are narrowing, focusing on specific sequences, formulations, and production methods.
Patent Validity and Challenges
- Novelty and Inventiveness: CN103957888 claims a novel antibody with unique variable region sequences compared to trastuzumab, meeting patentability criteria.
- Potential Challenges:
- Overlap with prior art: Existing patents for HER2 antibodies could challenge CN103957888's novelty, especially if similar sequences or methods are known.
- Patent durability: The narrow claims may be easier to design around but could be vulnerable if broader patents are enforced.
Regional and Global Context
- China Patent Law: Protects pharmaceuticals for 20 years from filing date, typically until 2034 for this patent.
- Global Extensions: Henlius is pursuing international patent filings, including filings under the Patent Cooperation Treaty (PCT), aiming to extend protection beyond China.
Strategic Implications for Developers
- Innovators must monitor CN103957888 and related patents for potential infringement issues.
- Biosimilar developers may design around specific sequences or production methods protected by this patent.
- Patent expiration in 2034 opens opportunities for generic biosimilar entry.
Summary Table: Key Attributes of CN103957888
| Aspect |
Details |
| Patent Number |
CN103957888 |
| Filing Date |
August 2014 |
| Publication Date |
July 2015 |
| Patent Term |
20 years from filing (expires 2034) |
| Protected Subject |
HER2-specific monoclonal antibody with particular sequences |
| Claims |
16, including antibody structure, production, treatment use |
Conclusion
Patent CN103957888 claims a specific HER2-targeting antibody with sequence modifications, covering production methods and therapeutic use. Its scope is sufficiently narrow, focusing on particular variants, but overlaps with existing HER2 antibody patents necessitate careful freedom-to-operate analysis.
Key Takeaways
- The patent covers specific antibody sequences and formulations targeting HER2.
- It is a strategic asset for Henlius, securing proprietary rights for biosimilar or innovative HER2 therapies in China.
- The patent landscape exhibits significant activity, with multiple filings related to HER2 antibodies and conjugates.
- Companies should analyze sequence similarities and patent claims to assess infringement risk.
- International patent applications are ongoing, aiming to extend protection beyond China.
FAQs
Q1: Can Henlius expand the patent scope to broader HER2 antibodies?
A1: Broader claims typically require additional inventive steps, but Henlius can file divisional or continuation applications to extend claim scope.
Q2: How does CN103957888 compare to trastuzumab patents?
A2: The sequences are related but differ enough to avoid direct infringement, though close similarities mean competitors should analyze sequence details carefully.
Q3: Are there opportunities for biosimilar development around this patent?
A3: Yes, particularly if competitors design antibodies with different sequences or production methods outside the patent claims.
Q4: When does CN103957888 expire?
A4: The patent expires in 2034, 20 years from the August 2014 application date.
Q5: Is China a significant market for HER2 biosimilars?
A5: China is one of the largest markets for biosimilars, with increasing approval and adoption of HER2-targeting therapies.
References
[1] Patent CN103957888. (2015). HER2-specific monoclonal antibody. State Intellectual Property Office of China.
