IDH1 and biliary tract neoplasm: In a randomized phase III study enrolling 230 patients with IDH1 mutated biliary tract cancer, ivosidenib, an oral inhibitor of mutated IDH1, significantly improved progression-free survival compared with the placebo (2.7 months vs. 1.4 months, hazard ratio 0.37, p < 0.0001) [61].