The ‘double tumor-associated antigen targeting’ strategy (i.e., targeting two instead of one tumor-associated antigen) has demonstrated its power in generating durable tumor remission; for instance, concomitant expression of CARs targeting CD19/CD20 (28), CD19/CD22 (26), or CD19/CD123 (27) on T cells creates better therapeutic response than pooling T cells carrying either CAR together. The gene discussed is CD19; the disease is neoplasm.