Daniel W Lee

Immune effector cell (IEC) therapies offer durable and sustained remissions in significant numbers of patients with hematological cancers. While these unique immunotherapies have improved outcomes for pediatric and adult patients in a number of disease states, as 'living drugs,' their toxicity profiles, including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), differ markedly from conventional cancer therapeutics. At the time of article preparation, the US Food and Drug Administration (FDA) has approved tisagenlecleucel, axicabtagene ciloleucel, and brexucabtagene autoleucel, all of which are IEC therapies based on genetically modified T cells engineered to express chimeric antigen receptors (CARs), and additional products are expected to reach marketing authorization soon and to enter clinical development in due course. As IEC therapies, especially CAR T cell therapies, enter more widespread clinical use, there is a need for clear, cohesive recommendations on toxicity management, motivating the Society for Immunotherapy of Cancer (SITC) to convene an expert panel to develop a clinical practice guideline. The panel discussed the recognition and management of common toxicities in the context of IEC treatment, including baseline laboratory parameters for monitoring, timing to onset, and pharmacological interventions, ultimately forming evidence- and consensus-based recommendations to assist medical professionals in decision-making and to improve outcomes for patients.

Abstract: With immunotherapy innovations for cancer treatment, in particular chimeric antigen receptor (CAR) T cells, becoming more successful and prevalent, strategies to mitigate and manage their toxicities are required. Anti-CD19 CAR T-cell therapy has revolutionized the treatment of relapsed/refractory pediatric and adult acute lymphoblastic leukemia and refractory adult non-Hodgkin lymphoma, resulting in the expanded use of CAR T cells in multicenter trials and as US FDA-approved products. Cytokine release syndrome (CRS) and CAR-associated neurotoxicity, which can occur independently or concurrently with CRS, are two potentially life-threatening toxicities of CAR T-cell therapy. In this review, we will focus on describing the pathophysiology behind CRS, the proposed definitions of and grading systems for CRS, and innovative options for treating this potentially lethal systemic inflammatory condition. Keywords: adoptive cellular immunotherapy, CD19 CAR T cells, tocilizumab, CAR-associated neurotoxicity, Immune Effector Cell-Associated Neurotoxicity Syndrome, leukemia