...received gilteritinib for treatment of R/R FLT3mut+ AML...co-mutations in DNMT3A, NPM1 and NRAS were observed...patients with MAPK pathway activating mutations (e.g. NRAS and PTPN11) had lower CRc (37.5% vs 59.5%) and poorer median survival than other patients (3.3 months vs 7.5 months) (HR 2.2- 95% CI 1.1-4.4) p value <0.01.