Leukemia is the most common childhood malignancy and cause of pediatric cancer death. Significant advances in the cure rates of B-cell acute lymphoblastic leukemia (B-ALL) and T-cell acute lymphoblastic leukemia (T-ALL) have been achieved; however, patients with refractory or relapsed B-ALL or T-ALL continue to have poor outcomes. Immunotherapy is a revolutionary treatment aimed to improve survival and reduce the toxicity of chemotherapy by harnessing the patient’s own immune system to target cancer cells. Several immunotherapies have been developed including monoclonal antibodies, antibody drug conjugates, Bispecific T-cell engagers (BiTEs), and chimeric antigen receptor T-cell (CAR-T) therapy. Immunotherapy has been shown to have efficacy in relapsed acute leukemia; however, antigen escape relapse remains a challenge and the duration of effect is unknown. Nevertheless, immunotherapy holds the potential to significantly improve outcomes in relapsed pediatric acute B-ALL and T-ALL and is actively being studied in upfront therapy.

B-ALL, T-ALL, Immunotherapy, Monoclonal Antibodies, Antibody-drug Conjugates Bispecific T-Cell Engager (BiTE), Chimeric Antigen Receptor (CAR) T-Cells