CD19 and congenital rubella syndrome: ,11 Nevertheless, acute adverse events such as treatment-related severe cytokine release syndrome (CRS), neurotoxicity, as well as the development of CD19 CAR-T refractory escape variants in a significant proportion of patients treated limit their therapeutic success.12, 13, 14, 15 Moreover, CAR-T treatment beyond CD19 and B cell maturation antigen (BCMA) remains challenging, as expression of other targets in contrast to the B cell-lineage antigens is less differentiated.