The U.S. Food and Drug Administration recently approved lisocabtagene maraleucel (liso‐cel) for the treatment of CLL and small lymphocytic lymphoma (SLL); liso‐cel, a CD19 targeted CAR T‐cell therapy, is administered as equal doses of CD8 and CD4 CAR T cells.62 This evidence concerns the gene CD19 and B-cell chronic lymphocytic leukemia.