PK/PD study in the MOLM-13 xenograft model. (A-B) PK/PD study was conducted in the MOLM-13 xenograft model separately from the efficacy study. Single oral administration of FF-10101 at 5 mg/kg was given to mice at 15 days after intravenous injection of MOLM-13 cells. Blood and BM were sampled at 2, 4, 8, and 16 hours after administration (n = 3/each time point). Four mice were administered as the vehicle administration group and were euthanized after 16 hours. Plasma concentrations of FF-10101 at each time point were analyzed by LC/MS/MS (panel A). ERK phosphorylation levels in BM were analyzed by western blotting (panel B). Bars show mean ± SD.