KMT2A and acute lymphoblastic leukemia: However, oral administration of ABT-199 in addition to the injection of 30 mg/kg of dexamethasone and RK-20449 to the MLL-ALL recipients (Patients 4 and 11) resulted in complete elimination of hCD45+ cells in the PB (Fig. 4c), BM (Fig. 4d) and spleen (Fig. 4e).