Advanced cholangiocarcinoma is associated with a particular impaired survival prognosis. So far targeted therapies with relevant clinical efficacy are missing. isocitrate dehydrogenase 1 (IDH1) mutations are observed in a fraction of patients with cholangiocarcinoma. The ClarIDHy, a global, phase III, randomized, double-blind study of ivosidenib ersus placebo in patients with advanced cholangiocarcinoma with an IDH1 mutation met its primary endpoint. Therefore, ivosidenib is a promising new treatment opportunity in patients with Advanced cholangiocarcinoma harboring an IDH1 mutation.