Inotuzumab ozogamicin in adult acute lymphoblastic leukemia: Development, current status, and future directions

Abstract Inotuzumab ozogamicin (InO) is an antibody‐drug conjugate approved for the treatment of relapsed/refractory B‐cell acute lymphoblastic leukemia (ALL). Several clinical trials are investigating InO in combination with low‐intensity chemotherapy or other anti‐ALL–targeted therapies in the salvage and frontline settings, notably in older adults who often cannot tolerate intensive chemotherapy and tend to have higher‐risk disease. InO is also increasingly used to bridge patients to hematopoietic stem cell transplantation (HSCT), in sequence with chimeric antigen receptor T‐cell therapy, to eliminate measurable residual disease and to prevent post‐HSCT relapse. Veno‐occlusive disease/sinusoidal obstruction syndrome is a potential complication of InO treatment, particularly when followed by HSCT. Herein, the authors review the historical development and current status of InO, strategies for mitigating the risk of InO‐related veno‐occlusive disease/sinusoidal obstruction syndrome, and future directions for InO research and clinical use.