Lancet Rheumatol

New toxicity syndrome identified in CAR T-cell therapy for autoimmune diseases

May 9, 2025

Study details: This observational study examined autoimmune disease-specific adverse events associated with CD19-targeting CAR T-cell therapy. Conducted at two centers in Germany, the study included 39 patients with autoimmune diseases (20 with systemic lupus erythematosus, 13 with systemic sclerosis, and six with idiopathic inflammatory myopathy) treated between March 1, 2021, and October 31, 2024. Patients were monitored for local organ-specific reactions, termed local immune effector cell-associated toxicity syndrome (LICATS), following CAR T-cell infusion.

Results: LICATS was observed in 30 (77%) patients, with a median onset of 10 days post-infusion and a median duration of 11 days. The most commonly affected organs were the skin (35%) and kidneys (22%). Most reactions were mild (grade 1: 65%, grade 2: 30%), with only three cases requiring prolonged or new hospitalization (grade 3). All LICATS events resolved without sequelae.

Clinical impact: LICATS represents a new form of toxicity specific to autoimmune disease patients receiving CD19-targeting CAR T-cell therapy. It's characterized by self-limited, organ-specific, and generally mild reactions, occurring exclusively during the B-cell aplasia phase and involving previously affected organs. This finding underscores the importance of monitoring and managing these specific toxicities in this patient population.

Source:

Hagen M, et al. (2025, April 30). Lancet Rheumatol. Local immune effector cell-associated toxicity syndrome in CAR T-cell treated patients with autoimmune disease: an observational study. https://pubmed.ncbi.nlm.nih.gov/40318690/