CDH17: The New Golden Target for Gastrointestinal Tumor ADCs

Following HER2, PD-1, and CLDN18.2, CDH17 (Cadherin-17), with its advantages of high tumor targeting and favorable endocytosis properties, has emerged as a key emerging target for innovative pharmaceutical companies in 2026. As a critical transmembrane glycoprotein of gastrointestinal epithelial cells, CDH17 exhibits specific high expression in colorectal, gastric, and pancreatic cancers; notably, its expression rate approaches 100% in colorectal cancer^[1]. Due to its high tumor targeting and excellent endocytosis properties, CDH17 is regarded by the industry as one of the most promising "golden targets" in the field of gastrointestinal tumors, attracting accelerated layout from innovative pharmaceutical companies worldwide. 

Capital Accurately Bets on Differentiation: Three Major Technical Routes Racing Ahead

As the clinical value of the target is gradually validated, the primary market continues to increase its investment in differentiated CDH17 pipelines. Funds are primarily flowing into three differentiated technical routes: dual-target ADCs, TCE bispecific antibodies, and CAR-T therapies. This differentiated pipeline competition forces pharmaceutical companies to conduct precise, domain-specific antibody screening, making fragmented recombinant CDH17 proteins an essential requirement for preclinical R&D. 

Overview of a selection of Core Financing and 2026 Progress in the CDH17 Track 

ADCs Lead the Track, Epitope Selection Becomes Key to Winning

According to incomplete statistics, there are currently 89 CDH17 drugs and 342 R&D pipelines globally. The track has bifurcated into two mainstream routes: ADCs and dual-target ADCs primarily select EC1-4 to achieve highly efficient killing, whereas TCEs and CAR-T therapies mostly target EC5-7 to inhibit tumor metastasis. Both routes require precise epitope screening and validation, which makes high-quality fragmented proteins an indispensable raw material for building differentiated pipeline barriers. 

Overview of the Competitive Landscape in the CDH17 Track

As the world's first CDH17 ADC to publish clinical data, AMT-676 demonstrated clear anti-tumor activity, with an objective response rate (ORR) of 18.4% (23/125) and a disease control rate (DCR) as high as 91.1% (114/125). In the ADC drug track, the core advantages of the CDH17 target are primarily reflected in two aspects:

• Precise and highly efficient targeting strategy: Most ADC pipelines precisely lock onto the membrane-distal regions of EC1-2/EC3-4. Epitopes in this area are fully exposed, which not only provides high antibody binding affinity but also induces rapid endocytosis, ensuring a sufficient amount of toxin enters the interior of the cell.
• Overcoming tumor heterogeneity: Addressing the high heterogeneity of solid tumors, the small molecule toxins released by ADC drugs exhibit a "bystander effect," capable of penetrating cell membranes to kill surrounding tumor cells with low antigen expression. 
  

Mechanism of action of CDH17 antibody-drug conjugates^[1] 

Flexible Combinations from Single to Multiple Domains: Full-Domain CDH17 Tool Proteins
Facing the complex seven-domain structure of CDH17 and the differentiated target requirements of various technical routes, KACTUS, leveraging its mature recombinant protein expression platform, has launched a series of fully human CDH17 fragmented proteins, providing robust foundational support for gastrointestinal tumor drug R&D.

Full-Domain Coverage, Refined Fragmented Product Matrix

• Single-domain proteins: We offer independent Domain 1-7 monomers, which serve as ideal tools for refined epitope mapping and specificity validation. 
  
• Multi-domain combinations: We have launched various combination formats such as Domain 1-2, Domain 3-4, and Domain 5-7 to maximally restore the native spatial conformation of the protein on the cell surface, ensuring that the screened antibodies possess higher affinity and functionality. 

Ultra-Low Endotoxin, Meeting Stringent Experimental Standards

• High purity: Removes impurity interference, ensuring the accuracy of binding activity data. 
  
• Low toxicity: Suitable for endotoxin-sensitive cell culture and in vivo efficacy evaluations, accelerating the IND application process. 
  

Product List

References

[1] Wang R, Fang P, Chen X, et al. Overcoming multidrug resistance in gastrointestinal cancers with a CDH17-targeted ADC conjugated to a DNA topoisomerase inhibitor. Cell Rep Med. 2025;6(7):102213. doi:10.1016/j.xcrm.2025.102213