NKTR and Ewing sarcoma: Among them, Luo et al. showed that combination therapy with an IL-15 agonist NKTR-255 and a CD47 blockade magrolimab enhanced chimeric antigen receptor (CAR)-NK cytotoxicity and macrophage phagocytic activity along with decreased primary tumor growth and prolonged animal survival in PDX-based Ewing sarcoma (ES) xenograft mouse models [192].