First, we tested the ability of a CD20-based off-switch incorporated within the CAR to sensitize cells to rituximab and found effective depletion of BCMA TurboCAR T™ cells by complement or effector cells in vitro and in vivo in the presence of the antibody. In addition, we confirmed rapid inhibition of BCMA TurboCAR T™ cells by the protein tyrosine kinase inhibitor dasatinib, which has been shown to interfere with LCK activity. The prolonged persistence and antitumor responses seen in preclinical models along with a favorable safety profile of BCMA TurboCAR™ T cells support clinical investigation of ALLO-605 in relapsed or refractory multiple myeloma.