Cholangiocarcinoma is a rare, aggressive cancer affecting the bile ducts both in and outside of the liver. Experts estimate that 8000 people in the United States are diagnosed with this cancer each year, although the actual number is likely to be higher because it can be hard to diagnose and may be misclassified as other types of cancer. Patients living with IDH1-mutated cholangiocarcinoma, especially those whose disease progresses following chemotherapy, are in urgent need of new treatment options, says Dr. Rachna Shroff, chief of gastrointestinal medical oncology at the University of Arizona Cancer Center. Ivosidenib tablets have been granted FDA approval for the treatment of adult patients with previously treated, locally advanced or metastatic cholangiocarcinoma with an IDH1 mutation, marking the first and only targeted therapy to be approved for this patient population. It was previously granted Priority Review by the FDA, which accelerated the review timeline.