IDH1 and cholangiocarcinoma: Meanwhile, a phase II trial currently underway at the National Cancer Institute is assessing the effectiveness of the PARP inhibitor olaparib in the treatment of patients with glioma, cholangiocarcinoma, or other solid tumors with IDH1 or IDH2 mutations. The primary endpoint of this trial is the overall response rate in subjects within the three tumor cohorts, with secondary goals of survival assessment, duration of response, and safety of olaparib as monotherapy [33].