CLDN18 (Zolbetuximab Biosimilar) Recombinant Monoclonal Antibody

This recombinant monoclonal antibody is developed as a research-grade biosimilar to Zolbetuximab, targeting claudin-18 isoform 2 (CLDN18.2), a tight junction protein that is normally restricted to gastric epithelial cells. CLDN18.2 plays a critical role in maintaining epithelial barrier integrity and cellular polarity. This protein exhibits aberrant expression in various malignancies, particularly gastric and gastroesophageal junction adenocarcinomas, where it becomes accessible on the cell surface of tumor cells while remaining largely absent in normal tissues outside the stomach. This restricted expression pattern makes CLDN18.2 an attractive target for cancer research and therapeutic development.

Zolbetuximab is a chimeric monoclonal antibody, with its variable region derived from mice and its constant region from human IgG1. Zolbetuximab is a first-in-class therapeutic agent that has demonstrated clinical efficacy in CLDN18.2-positive gastric and gastroesophageal cancers through antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity mechanisms. This biosimilar antibody serves as a valuable research tool for investigating CLDN18.2 biology, exploring tumor-selective targeting strategies, and studying mechanisms of antibody-mediated tumor cell killing in gastrointestinal cancers and other CLDN18.2-expressing malignancies.