TPM3-NTRK1 fusion gene-positive KM12 colorectal cancer cells were highly sensitive to gilteritinib with an IC50 of <30 nM and TPM3-NTRK1 WT Ba/F3 cells were also sensitive to gilteritinib (IC50; WT, 13.3 nM). The gene discussed is NTRK1; the disease is colorectal cancer.