"Giant" CAR T cells huCART19-IL18 target CD19 and secrete interleukin-18 (IL18), which enhances their persistence and antitumor activity[1]. The therapy was tested in a phase I trial in patients with relapsed B-cell acute lymphoblastic leukemia (B-ALL)[1]. Data on its promising results were presented at the annual meeting of the American Society of Hematology[1]. IL18 supports the immune system by recruiting additional immune cells and protecting CAR T cells from attack[1]. No new safety issues have been reported in addition to the known side effects of CAR T therapy, such as cytokine release syndrome and neurotoxicity, which have been successfully managed[1]. Analysis of patient blood samples showed strong evidence of a high response rate due to the addition of IL18[1]. This is the first case of testing cytokine-boosted CAR T cells in patients with blood cancers[1].