Several targeted treatments for iCCA are being investigated.38 About 13% of patients have isocitrate dehydrogenase 1 (IDH1) mutations and about 14% of patients have fibroblast growth factor receptor (FGFR) 2 fusions.39,40 In a phase III trial, patients with an IDH1 mutation and advanced CCA who had progressed on previous therapy were randomized between ivosidenib and placebo. The gene discussed is IDH1; the disease is cholangiocarcinoma.