A total of 113 R/R AML patients were analyzed; most of them received gilteritinib as a single-agent therapy (62.8%), while the rest of the patients were treated with gilteritinib-based combinations (intensive chemotherapy (31%), hypomethylating agents 33%, venetoclax or hypomethylating and venetoclax 31%, and IDH inhibitors 5%). This evidence concerns the gene IDH1 and acute myeloid leukemia.