Tarextumab (OMP-59R5) is a fully human IgG2 monoclonal antibody designed to selectively target and inhibit the signaling of Notch2 and Notch3 receptors. preclinical and clinical studies have demonstrated that inhibition of the Notch2/3 pathway with chemotherapeutic agents is efficacious across a broad spectrum of epithelial tumors, including breast, lung, ovarian, and pancreatic cancers, thereby establishing Tarextumab as a promising candidate for oncological research and development.