A Study to Evaluate the Efficacy and Safety of Pemigatinib in Participants With Advanced/Metastatic or Surgically Unresectable Cholangiocarcinoma With FGFR2 Fusion or Rearrangements After at Least 1 Prior Line of Systemic Therapy

The purpose of this study is to confirm the efficacy and safety of pemigatinib in participants with advanced/metastatic or surgically unresectable cholangiocarcinoma with FGFR2 fusion or rearrangements after at least 1 prior line of systemic therapy.

Inclusion Criteria: * Histologically or cytologically confirmed unresectable, locally advanced or metastatic cholangiocarcinoma (CCA). * Documented FGFR2 fusion or rearrangement * Documented disease progression after at least 1 prior line of systemic chemotherapy, with or without immune checkpoint inhibitors (ICI). * Life expectancy ≥ 12 weeks. * An ECOG performance status of 0 to 1. * Measurable disease by CT or MRI based on RECIST v1.1 as determined by site radiology. * Willingness to avoid pregnancy or fathering children. Exclusion Criteria: * Prior treatment with any FGFR inhibitor for any indication. * Liver cirrhosis, Child-Pugh B and C. * Known CNS metastases or history of uncontrolled seizures, except participants with treated brain metastases and no evidence of progression for =\> 4 weeks and on stable or decreasing dose of corticosteroids for management of CNS metastases for =\>1 week. * Current evidence of clinically significant corneal or retinal as confirmed by ophthalmologic examination. * History of calcium and phosphate hemostasis disorder or systemic mineral imbalance with ectopic calcification of soft tissues. * History of hypovitaminosis D requiring supraphysiologic doses (eg, 50,000 UI/week) to replenish the deficiency. * Clinically significant or uncontrolled cardiac disease or history or presence of an abnormal ECG, which, in the investigator's opinion, is clinically meaningful. * Use of strong CYP3A4 inhibitors and inducers, moderate CYP3A4 inducers, and concomitant FGFR inhibitor, investigational drug and anticancer medication other than pemigatinib. * Women who are pregnant or breastfeeding. Other protocol-defined inclusion/exclusion criteria apply.