Novel immunotherapies and their role in the treatment of acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) remains incurable for many adult patients. The success observed in the pediatric population with intensive combination chemotherapy regimens is not matched in older populations due to inability to tolerate treatment and biological differences in the disease. The development of immune therapies has ushered in a new much needed approach to treat ALL in the adult population as well as in the pediatric population with relapsed or refractory disease. While not heavily studied in the upfront setting, immune therapies have demonstrated astounding results in patients with minimal residual disease (MRD) and those with relapsed and refractory disease. The wide array of immunotherapy available consists of simple unconjugated monoclonal antibodies, immunotoxins or drug conjugated monoclonal antibodies, bispecific T cell engagers, and chimeric antigen receptor (CAR) T cells. In this article, we review the clinical data, efficacy, toxicity, and future direction of these therapies.