This study will enroll participants with nonresectable or metastatic cholangiocarcinoma with an Isocitrate dehydrogenase protein, 1 (IDH1) mutation, who have previously received at least 1, but no more than 2, prior regimens for advanced disease. All participants will receive ivosidenib daily throughout multiple 28 day cycles. Study treatment will be administered until participant experiences unacceptable toxicity, disease progression, or other discontinuation criteria are met. Study visits will be conducted every week during Cycle 1 (Days 1, 8, 15, and 22), every other week during Cycles 2 and 3, and Day 1 of each cycle thereafter. After the last dose of treatment, participants will attend an end of treatment and a post-treatment follow-up visit, and participants will be followed to assess overall survival. Study visits may include a tumor assessment, physical exam, electrocardiogram (ECG), blood and urine analysis, and questionnaires.

Inclusion Criteria:

• Have nonresectable or metastatic cholangiocarcinoma and are not eligible for curative resection, transplantation or ablative therapies
• Have documented IDH1 gene-mutated disease from a tumor biopsy
• Have an ECOG PS score of 0 or 1
• Have an expected survival of 3 months or more
• Have at least one evaluable and measurable lesion
• Have disease progression following the most recent of 1 or 2 prior systemic regimens for advanced disease with progression on the treatment that was most recently given at a minimum, and must have received at least 1 gemcitabine- or 5-FU -containing regimen
• Have recovered from side effects associated with the prior treatment therapy
• Have adequate bone marrow function
• Have adequate hepatic (liver) and renal (kidney) function
• Women of child bearing potential must have a negative serum pregnancy test before starting study treatment, and use birth control during the study and for 90 days after the last dose of ivosidenib
• Fertile men with female partners of child bearing potential must use birth control during the study and for 90 days after the last dose of ivosidenib

Exclusion Criteria:

• Received a prior IDH inhibitor.
• Have known symptomatic brain metastases requiring steroids.
• Pregnancy, possibility of becoming pregnant during the study and breast-feeding women or woman who plans to restart breast-feeding after the study drug administration/intake.
• Are taking known strong cytochrome P450 (CYP) 3A4 inducers or sensitive CYP3A4 substrate medications with a narrow therapeutic window
• Have significant heart disease, including congestive heart failure, myocardial infarction (heart attack) unstable angina (chest pain) and/or stroke, within 6 months before starting the study
• Have a heart-rate corrected QT interval ≥450 msec or other factors that increase the risk of QT prolongation or arrhythmic events
• . Have active inflammatory gastrointestinal disease, chronic diarrhea, previous gastric resection or lap band dysphagia, short-gut syndrome, gastroparesis (paralysis of the stomach), or other conditions that limit the ingestion or gastrointestinal absorption of drugs administered orally.
• Have known medical history of progressive multifocal leukoencephalopathy (PML)

Qualified scientific and medical researchers can request access to anonymized patient-level and study-level clinical trial data.

Access can be requested for all interventional clinical studies:

• used for Marketing Authorization (MA) of medicines and new indications approved after 1 January 2014 in the European Economic Area (EEA) or the United States (US).
• where Servier is the Marketing Authorization Holder (MAH). The date of the first MA of the new medicine (or the new indication) in one of the EEA Member States will be considered for this scope.

In addition, access can be requested for all interventional clinical studies in patients:

• sponsored by Servier
• with a first patient enrolled as of 1 January 2004 onwards
• for New Chemical Entity or New Biological Entity (new pharmaceutical form excluded) for which development has been terminated before any Marketing authorization (MA) approval.

After Marketing Authorization in EEA or US if the study is used for the approval.

Researchers should register on Servier Data Portal and fill in the research proposal form. This form in four parts should be fully documented. The Research Proposal Form will not be reviewed until all mandatory fields are completed.