Petosemtamab

Disease progression and treatment resistance in colorectal and other cancers are driven by a subset of cells within the tumor that have stem-cell-like properties and long-term tumorigenic potential. These stem-cell-like cells express the leucine-rich G repeat-containing protein-coupled receptor 5 (LGR5) and have characteristics similar to tissue-resident stem cells in normal adult tissues such as the colon. Organoid models of murine and human colorectal and other cancers contain LGR5-expressing (LGR5+) stem-cell-like cells and can be used to investigate the underlying mechanisms of cancer development, progression, therapy vulnerability, and resistance. Petosemtamab employs three distinct mechanisms of action: EGFR ligand blocking, EGFR receptor internalization and degradation in LGR5+ cells, and Fc-mediated activation of the innate immune system by antibody-dependent cellular phagocytosis (ADCP) and enhanced antibody-dependent cellular cytotoxicity (ADCC).