…patient 5.02, who had a detectable D835Y mutation in ITD-alleles pre-treatment, achieved clearance of bone marrow blasts on 2000 mg of PLX3397, but subsequently relapsed with a highly resistant ITD+D835Y clone. These observations are consistent with our finding that D835V/Y mutations cause a lesser degree of resistance to PLX3397 in the absence of an ITD (Supplemental Figure 7a,b) and suggest that these mutations may retain clinical sensitivity to higher doses of PLX3397.