XB033

XB033 is an antibody-drug conjugate (ADC) being developed by Exelixis for the treatment of various cancers. It consists of a monoclonal antibody targeting Interleukin-13 receptor subunit alpha-2 (IL-13Rα2) conjugated to a topoisomerase I inhibitor payload. IL-13Rα2 is a tumor-associated antigen that is frequently overexpressed in several solid tumors, including glioblastoma, colorectal cancer, and melanoma, while showing limited expression in normal tissues. By targeting this receptor, XB033 is designed to deliver its cytotoxic payload directly to malignant cells, where it induces DNA damage and subsequent apoptosis. The drug is currently in preclinical development, with an Investigational New Drug (IND) filing anticipated in 2026.