The phase 3 ClarIDHy trial showed that ivosidenib in CCA patients with an IDH1 mutation who progressed after 2 prior chemotherapies derived a PFS benefit of 6.9 months and median OS of 10.8 months compared with 1.4 months and 9.7 months in the placebo group [19]. Here, IDH1 is linked to cholangiocarcinoma.