Blinatumomab: Bridging the Gap in Adult Relapsed/Refractory B-Cell Acute Lymphoblastic Leukemia

Adult patients with acute lymphoblastic leukemia who relapse after frontline therapy have extremely poor outcomes despite advances in chemotherapy and hematopoietic stem cell transplantation. Blinatumomab is a first-in-class bispecific T-cell engager that links T cells to tumor cells leading to T-cell activation and tumor cell lysis. In December 2014, the Food and Drug Administration approved blinatumomab for treatment of relapsed or refractory Philadelphia chromosome-negative precursor B-cell acute lymphoblastic leukemia. In a phase II trial, blinatumomab produced response rates of 43%, and 40% of patients achieving a complete remission proceeded to hematopoietic stem cell transplantation. Early use of blinatumomab was complicated with adverse effects, including cytokine release syndrome and neurotoxicity. Management strategies, including dexamethasone premedication and 2-step dose escalation during the first cycle of blinatumomab, have decreased the incidence and severity of these adverse effects. Blinatumomab currently is being studied for other B-cell malignancies and has the potential to benefit many patients with CD19+ malignancies in the future.