Blinatumomab, a BiTE-targeting CD3 on T cells and CD19 on B cells, has shown preclinical efficacy in CLL by inducing the autologous T-cell killing of CLL cells and exhibiting cytotoxicity against CLL cells in both R/R and treatment-naïve CLL cell lines [114]. This evidence concerns the gene CD19 and B-cell chronic lymphocytic leukemia.