Claudin 18.2 monoclonal antibodies are a promising class of therapeutic agents targeting the Claudin 18.2 protein, a tight junction protein that is highly expressed in various cancers, including gastric, pancreatic, and ovarian cancers. In normal tissues, Claudin 18.2 is predominantly expressed in differentiated gastric mucosal cells, but its upregulation in tumor cells makes it an attractive target for cancer therapy. These monoclonal antibodies, such as Zolbetuximab, work by binding specifically to the extracellular domain of Claudin 18.2, inducing antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) to kill cancer cells.