CD19 and precursor B-cell acute lymphoblastic leukemia: Very recently, while this paper was in preparation, a new study showed that, in 33 childhood and young adult B-ALL patients with prior mCD19 CAR exposure (CD19+ relapse, n = 15; B-cell recovery, n = 16; no response to prior CAR-T cells, n = 2), the overall response rate at 1 month after humanized CD19 CAR-T cell infusion was 64% [10].