In contrast, all 16 patients with various autoimmune disorders (8 with systemic lupus erythematosus, 4 with systemic sclerosis, 3 with idiopathic inflammatory myositis, and 1 with MG) who received conventional CAR‐Ts directed toward CD19 under an expanded access (“compassionate use”) protocol had severe (grade ≥ 3) neutropenia lasting median 14–16 days [17, 18]. This evidence concerns the gene CD19 and acquired idiopathic inflammatory myopathy.