In in vitro assays and in mouse xenograft models, ibrutinib enhances the killing activities of anti-CD19 CAR-T cells derived from CLL or MCL patients or normal donors, and improves CAR-T cell engraftment, tumor clearance and long-term remission in mice with xenografts of human CLL, ALL or MCL (Fraietta et al., 2016; Ruella et al., 2016). Here, CD19 is linked to B-cell chronic lymphocytic leukemia.