Abou-Alfa GK, Macarulla T, Javle MM, et al. Ivosidenib in IDH1-mutant, chemotherapy-refractory cholangiocarcinoma (ClarIDHy): a multicentre, randomised, double-blind, placebo-controlled, phase 3 study. Lancet Oncol 2020; 21: 796–807—In this Article, the first sentence in the Introduction should read “Isocitrate dehydrogenase 1 (IDH1) mutations are detected in approximately 13% (range 9–20%)…” This correction has been made to the online version as of January 29, 2024.