ES004: Potential Best-in-Class Monoclonal Antibody Targeting SIRPα
ES004 is a potential best-in-class monoclonal antibody targeting pan-allele signal-regulatory protein alpha (SIRPα).
SIRPα is an inhibitory receptor expressed mainly on myeloid cells and dendritic cells. Binding of CD47 to SIRPα delivers a “don't eat me” signal to suppress phagocytosis.Tumor cells frequently overexpress CD47 to evade immunosurveillance. To overcome this issue, ES004 stimulates potent macrophage-mediated phagocytosis against multiple tumor cells by blocking SIRPα. Unlike agents targeting CD47, targeting SIRPα is designed to avoid anemia, thrombocytopenia and antigen sink and improve the therapeutic window.