The combination of VTP50469 (menin inhibitor) and EPZ5676 (DOT1L inhibitor) was superior in decreasing cell viability in MLL-r leukemia cell lines sensitive to VTP50469 (MV4;11, MOLM13 and RS4;11)...Based on our preclinical in vitro findings, the co-inhibition of menin-DOT1L or menin-CDK9 is a promising approach for the treatment of MLL-r leukemia.