CD38 and neoplasm: Another strategy to reduce effects of antigenic loss on efficacy is development of CAR T cells simultaneously targeting multiple tumor antigens, such as BCMA with CD38 (58, 59), CS1 (60), or GPRC5D (49, 61, 62), as well as a novel approach of an anti-BCMA CAR with a CD38 chimeric costimulatory receptor to further drive lymphocyte activation (63), with continued studies ongoing.