In phase II ELIANA trial of Novartis’s tisagenlecleucel, which is a synthetic bio-immune product of anti-CD19 CAR T-cells, at least 61 of 75 pediatric and young adult B-ALL patients (81%) achieved CR and 15 of the responders (24.6%) went on to develop the antigen-negative or partially negative relapse [11]. The gene discussed is CD19; the disease is precursor B-cell acute lymphoblastic leukemia.