Blinatumomab (Blincyto®, CD3 × B lymphocyte antigen CD19) was the first bsAb to be ratified by the US Food and Drug Administration (FDA) for the treatment of relapsed or refractory acute lymphoblastic leukemia (AML) in 2014 (10, 11). The gene discussed is CD19; the disease is acute lymphoblastic leukemia.