Last updated: February 19, 2026
Patent KR102162587, granted in South Korea on October 21, 2019, to Celltrion, Inc., covers an antibody-drug conjugate (ADC) composition. The patent's claims are primarily focused on specific antibody-drug conjugates and their therapeutic applications, particularly in oncology. This analysis details the patent's core claims, its scope, and its position within the broader ADC patent landscape.
What is the Core Invention Protected by KR102162587?
The central invention of KR102162587 is a specific antibody-drug conjugate (ADC). This ADC is characterized by an antibody that targets a particular antigen and a cytotoxic payload linked to the antibody via a cleavable linker. The patent claims define the precise chemical structure of these components and their combination.
What Specific ADC Structures are Claimed?
The patent's claims detail the chemical entities and their structural relationships. Key aspects of the claimed ADC structures include:
- Antibody Component: The patent specifies antibodies that bind to certain cell surface antigens. While the exact target antigen is defined in the claims, the scope extends to antibodies with specific binding affinities and characteristics. For instance, certain claims might define antibodies that bind to a particular receptor with a dissociation constant (Kd) below a specified threshold.
- Cytotoxic Payload: The patent claims a range of cytotoxic agents that can be conjugated. These are typically small molecules designed to kill cancer cells. The specific payloads are often chosen for their potency and ability to be effectively linked.
- Linker: A critical element of the ADC is the linker that connects the antibody to the payload. KR102162587 claims specific linker chemistries, often designed to be stable in circulation and cleavable within the target cell. This cleavage is typically triggered by intracellular conditions such as pH or enzymatic activity, releasing the cytotoxic drug into the cancer cell. Examples of linker types include disulfide linkers or acid-labile linkers.
- Conjugation Ratio: The patent may also define the drug-to-antibody ratio (DAR), which is the average number of drug molecules attached to each antibody molecule. Different DAR values can impact efficacy, pharmacokinetics, and toxicity, and specific ranges are often claimed.
What Therapeutic Applications are Covered?
The patent's claims extend to the use of the claimed ADC compositions for treating various diseases, predominantly cancers. The therapeutic applications are based on the antigen targeted by the antibody.
- Oncological Indications: Claims typically cover the treatment of solid tumors and hematological malignancies. Specific cancer types may be enumerated in the claims, or the claims may be broader, covering any cancer expressing the targeted antigen. Examples could include breast cancer, lung cancer, ovarian cancer, or leukemia.
- Treatment Regimens: The patent may also describe specific dosage regimens, administration routes, and combinations with other therapeutic agents. This includes the amount of ADC to be administered and the frequency of administration.
What is the Legal and Technical Scope of the Patent?
The scope of KR102162587 is defined by its claims, which delineate the boundaries of patent protection. Understanding this scope is crucial for assessing freedom to operate and potential infringement.
What are the Key Independent Claims?
Independent claims are the broadest claims in a patent and define the core invention without reference to other claims. For KR102162587, independent claims likely cover:
- Claim 1: A specific antibody-drug conjugate chemical structure. This claim defines the ADC by its antibody, linker, and payload. It is the most critical claim for defining the protected composition.
- Claim X: A pharmaceutical composition comprising the ADC from Claim 1 and a pharmaceutically acceptable carrier. This claim covers the formulation of the ADC for therapeutic use.
- Claim Y: A method of treating a disease, such as cancer, comprising administering a therapeutically effective amount of the ADC from Claim 1 to a subject in need thereof. This claim covers the therapeutic use of the ADC.
What are the Dependent Claims?
Dependent claims narrow the scope of the independent claims by adding further limitations or specifications. These claims provide fallback positions and protect specific embodiments of the invention. Examples include:
- Claims on specific antibody sequences: Defining antibodies based on their amino acid sequences.
- Claims on specific linker chemistries: Limiting the linker to a particular type or cleavage mechanism.
- Claims on specific payloads: Specifying the cytotoxic agent.
- Claims on specific antigen targets: Narrowing the antibody's target to a particular cell surface marker.
- Claims on specific cancer types or treatment methods: Further restricting the therapeutic application.
What are the Territorial Limitations?
KR102162587 is a granted patent in South Korea. This means its protection is legally enforceable only within the territory of the Republic of Korea. It does not provide protection in other countries unless corresponding patent applications have been filed and granted in those jurisdictions.
What is the Patent Landscape for Antibody-Drug Conjugates (ADCs)?
The ADC patent landscape is highly competitive and characterized by innovation across antibody engineering, linker technology, payload development, and novel therapeutic targets. KR102162587 exists within this dynamic environment.
Who are the Major Players in ADC Patenting?
Several pharmaceutical and biotechnology companies hold significant patent portfolios in the ADC space. These include:
- Gilead Sciences (formerly Immunomedics): With sacituzumab govitecan (Trodelvy).
- Seagen (now part of Pfizer): With a history of developing ADCs like adagrasib (Adcetris) and polatuzumab vedotin (Polivy).
- Daiichi Sankyo: A major innovator with its proprietary ADC technology platform (e.g., Enhertu).
- Genentech/Roche: A long-standing presence in antibody development and oncology.
- AbbVie: Actively developing ADCs.
- Merck: Investing in ADC technology.
- Moderna: Exploring mRNA-based ADC approaches.
Celltrion, the assignee of KR102162587, is also a significant player, particularly known for its biosimil and novel biologic development.
What are the Key Technological Trends in ADC Patents?
Current trends in ADC patenting reflect advancements in the field:
- Novel Linker Technologies: Development of more stable, cleavable, and site-specific linkers to improve therapeutic index and reduce off-target toxicity.
- Advanced Payload Chemistries: Introduction of new classes of highly potent cytotoxic agents, including DNA-damaging agents, microtubule inhibitors, and others.
- Next-Generation Antibody Engineering: Patents covering antibody fragments, bispecific antibodies, and antibodies with modified effector functions for enhanced targeting or payload delivery.
- Site-Specific Conjugation: Technologies that precisely attach the drug payload to specific sites on the antibody, leading to homogeneous ADCs with improved pharmacokinetics and efficacy.
- Novel Target Antigens: Identification and patenting of new cell surface antigens that are highly expressed on specific cancer cells but minimally expressed on healthy tissues.
- Combination Therapies: Patents covering the use of ADCs in combination with other cancer treatments, such as immunotherapies or chemotherapy.
- Manufacturing Processes: Patents related to the efficient and scalable manufacturing of ADCs, including upstream (antibody production) and downstream (conjugation) processes.
How Does KR102162587 Compare to Other ADC Patents?
The novelty and inventiveness of KR102162587 are assessed relative to the prior art. Its patentability hinges on whether the claimed ADC structures and their uses were previously known or obvious.
- Differentiation: Celltrion's patent likely differentiates itself through specific antibody sequences, unique linker designs, particular payloads, or novel combinations thereof.
- Prior Art: The scope of protection granted by KR102162587 is limited by existing patents and published literature covering similar ADCs. Examination during the patent prosecution process would have involved comparing the claims against this prior art. For example, if a similar ADC targeting the same antigen with a comparable linker and payload was already disclosed, the claims would have been narrowed to retain patentability.
- Freedom to Operate (FTO): Companies developing ADCs need to conduct FTO analyses to ensure their products do not infringe on existing patents like KR102162587. This involves scrutinizing the claims of relevant patents and assessing whether the new product falls within their scope.
What are the Implications for R&D and Investment?
The existence and scope of KR102162587 have direct implications for research and development strategies and investment decisions within the pharmaceutical industry.
R&D Strategy Considerations:
- Target Antigen Selection: If KR102162587 covers ADCs targeting a specific antigen, companies planning to develop ADCs against that same antigen must carefully review the patent's claims. They may need to design ADCs that bind to a different epitope, use a distinct linker/payload combination, or develop a non-infringing antibody.
- Linker and Payload Innovation: The patent's claims on linker chemistry and payloads can guide R&D efforts. Companies may focus on developing novel linker technologies or payloads that fall outside the scope of existing patents, thereby creating their own intellectual property.
- Combination Approaches: Exploring therapeutic combinations that utilize ADCs not covered by this patent, or combinations where this patent's ADC is a component, could be a strategic avenue.
Investment Decision Factors:
- Competitive Landscape: For investors, understanding the patent landscape, including patents like KR102162587, is crucial for assessing the competitive intensity and potential market entry barriers for new ADC products.
- Infringement Risk: Companies holding patents like KR102162587 have the right to sue for infringement. Investors need to evaluate the risk of such litigation for companies developing competing products.
- Unmet Medical Needs: Investment decisions are also guided by identifying therapeutic areas with significant unmet medical needs that can be addressed by novel ADC therapies, potentially sidestepping existing patent claims.
- Licensing Opportunities: Patents can represent opportunities for licensing agreements, providing revenue streams for patent holders and access to technology for licensees.
Key Takeaways
- Patent KR102162587, held by Celltrion, Inc., protects specific antibody-drug conjugate (ADC) compositions, their pharmaceutical formulations, and methods of treatment, primarily for cancer.
- The patent claims define the ADC by its antibody component, cytotoxic payload, and the linker connecting them, with specific structural and functional limitations.
- The scope of protection is limited to the Republic of Korea, delineating where legal enforcement is possible.
- The ADC patent landscape is dynamic and competitive, featuring major pharmaceutical and biotechnology companies and focusing on innovations in linker technology, payloads, antibody engineering, and novel targets.
- Understanding the claims and scope of KR102162587 is essential for R&D strategy, freedom-to-operate analyses, and informed investment decisions in the ADC field.
Frequently Asked Questions
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Does KR102162587 cover all antibody-drug conjugates?
No, KR102162587 covers only specific antibody-drug conjugate compositions as defined by its claims, including particular antibodies, linkers, and payloads, and their therapeutic uses. It does not broadly cover the entire field of ADCs.
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Can a company manufacture an ADC in South Korea if it targets the same antigen as the one claimed in KR102162587?
Manufacturing an ADC in South Korea that falls within the scope of the claims of KR102162587 would likely constitute infringement. Companies must conduct a freedom-to-operate analysis to determine if their specific ADC composition and use are covered by the patent claims.
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What is the expiration date of patent KR102162587?
The expiration date of a South Korean patent is generally 20 years from the filing date, subject to patent term extensions for certain pharmaceutical patents. The exact expiration date requires reference to the patent's filing date and any applicable extensions.
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How does the linker chemistry described in KR102162587 compare to other ADC linker technologies?
The specific linker chemistry claimed in KR102162587 is defined by the patent. A comparison would involve analyzing its cleavability, stability, and conjugation site relative to other published or patented linker technologies, such as those employed by competitors like Seagen or Daiichi Sankyo.
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If a company develops an ADC with a similar but not identical structure, could it still infringe KR102162587?
Yes, infringement can occur through literal infringement, where the accused product falls directly within the patent claims, or through the doctrine of equivalents, where a product is substantially the same in function, way, and result, even if not identical. A detailed infringement analysis would be necessary.
Citations
[1] Celltrion, Inc. (2019, October 21). Antibody-drug conjugate composition and method of preparation thereof. KR Patent 102162587.
