Intrathecal dexamethasone as an approach for immune effector cell-associated neurotoxicity syndrome after CAR T cell therapies

Introduction . The use of T-lymphocytes with a chimeric antigen receptor (Chimeric Antigen Receptor T-Cells, CAR T) has shown its effectiveness in the treatment of relapsed/refractory forms of B-cell acute lymphoblastic leukemia (B-ALL) with CNS involvement. A formidable complication of this treatment is immune effector cell-associated neurotoxicity syndrome (ICANS). Aim : to present clinical observations of patients with ICANS in whom, along with systemic administration of dexamethasone and anakinra, a therapeutic effect was achieved by intrathecal administration of dexamethasone. Main Findings . In 2 patients with relapsed B-ALL, ICANS developed after infusion of autologous anti-CD19 CAR T-lymphocytes. In both cases, the concentration of interleukin-6 (IL-6) in the cerebrospinal fl uid was many times higher than that in the blood, which indicated local production of the cytokine in the CNS. In addition to therapy with intravenous dexamethasone and anakinra, intrathecal administration of dexamethasone was performed, which led to rapid improvement of the patients’ condition.