In NSG mice engrafted with PD AML cells harboring MLL1-r (MLL-AF9) and FLT3-TKD, combined therapy with SNDX-5613 and OTX015 for one or for 6 weeks, as compared to each drug alone, was also significantly superior in reducing the AML burden, as well as significantly improving survival of the mice, respectively (Fig. 7C, D). The gene discussed is FLT3; the disease is acute myeloid leukemia.