Neurotoxicity Associated with CD19-Targeted CAR-T Cell Therapies

Neurotoxicity is an important and common complication of chimeric antigen receptor-T cell therapies. Acute neurologic signs and/or symptoms occur in a significant proportion of patients treated with CD19-directed chimeric antigen receptor-T cells for B-cell malignancies. Clinical manifestations include headache, confusion, delirium, language disturbance, seizures and rarely, acute cerebral edema. Neurotoxicity is associated with cytokine release syndrome, which occurs in the setting of in-vivo chimeric antigen receptor-T cell activation and proliferation. The mechanisms that lead to neurotoxicity remain unknown, but data from patients and animal models suggest there is compromise of the blood-brain barrier, associated with high levels of cytokines in the blood and cerebrospinal fluid, as well as endothelial activation. Corticosteroids, interleukin-6-targeted therapies, and supportive care are frequently used to manage patients with neurotoxicity, but high-quality evidence of their efficacy is lacking.