TAS-120 is a potent and selective inhibitor of fibroblast growth factor receptor (FGFR) isoforms, particularly FGFR1, FGFR2, and FGFR3. It is primarily developed for the treatment of cancers driven by aberrant FGFR signaling, such as certain types of cholangiocarcinoma, urothelial carcinoma, and other solid tumors with FGFR genetic alterations. Due to its ability to overcome resistance mutations that develop with earlier-generation FGFR inhibitors, TAS-120 is used in patients who have progressed on prior FGFR-targeted therapies. It is administered orally and has shown clinical activity in phase I and II trials, offering a therapeutic option for tumors with limited treatment alternatives. Its development represents a significant advancement in precision oncology, especially for patients with FGFR-fusion or FGFR-mutated cancers.