,64,65 In 2020, in the ClarIDHy phase 3 trial—the only completed phase 3 trial to date assessing a molecularly targeted agent in BTC—ivosidenib demonstrated clinical benefit in patients with IDH1-mutated CCA who had received up to two previous treatments for advanced disease (median OS 10.3 months, median PFS 2.7 months).12 Here, IDH1 is linked to cholangiocarcinoma.