Local immune effector cell-associated toxicity syndrome in CAR T-cell treated patients with autoimmune disease: an observational study

CD19-targeting chimeric antigen receptor (CAR) T-cell therapy has advanced treatment strategies for severe autoimmune diseases such as systemic lupus erythematosus (SLE), systemic sclerosis, and idiopathic inflammatory myopathy. Data regarding side-effects are mostly generated from patients with malignancies, but little is known about autoimmune disease-specific adverse events. This study aimed to describe autoimmune disease-specific adverse events that occur with CAR T-cell therapy.

In this observational study, patients of any age with autoimmune disease receiving CD19-targeting CAR T-cell therapy in two centres in Germany with a follow-up of at least 30 days were assessed for local organ-specific reactions occurring after CAR T-cell infusion. Observed reactions were documented according to localisation, time of onset, and duration, and were graded for severity (grade 1: spontaneous resolution; grade 2: glucocorticoid treatment due to symptoms lasting >1 week or presence of relevant inner organ involvement; grade 3: prolonged or new hospitalisation; grade 4: intensive care treatment). People with related lived experience were involved in the study design and implementation.