Background & Aims: To evaluate safety and efficacy of FGFR1–3 kinase inhibitor derazantinib, in advanced intrahepatic cholangiocarcinoma (iCCA) harboring FGFR2 fusions or rearrangements ( FGFR2 F ), mutations ( FGFR2 M ), or amplifications ( FGFR2 A ), previously treated with chemotherapy. Approach & Results: Open-label, non-controlled Phase 2 trial. Patients with advanced iCCA, ≥1 prior chemotherapy, and FGFR2 F (Substudy 1) or FGFR2 M /FGFR A (Substudy 2), received once-daily oral derazantinib 300 mg until disease progression, unacceptable toxicity, consent withdrawal or investigator decision to stop. Efficacy was assessed by central radiology review using RECIST v1.1. Primary endpoints were objective response rate (ORR; Substudy 1) and 3-month progression-free survival (PFS3; Substudy 2). Other endpoints were PFS, ORR (Substudy 2), disease control rate (DCR), duration of response (DOR), and overall survival (OS). In Substudy 1, ORR and DCR were 22.3% (23/103 partial responses) and 75.7%, respectively; median (95% CI) PFS was 8.1 (5.5,8.3) months, DOR was 6.5 (4.6,9.2) months, and OS was 17.2 (12.5,22.4) months. In Substudy 2, PFS3 was 63% (27/43), ORR was 9.3% (3 partial, 1 complete response), DCR was 69.8%, and OS was 11.9 (8.4,15.9) months. There were no Grade 4 or 5 drug-related events. FGFR inhibitor class-specific toxicities included drug-related hyperphosphataemia (38%, Grade 3: 3%) and dry eye (36%). Nail disorders (10%, any grade or causality), stomatitis (5%), retinal events (5%), and palmar-plantar erythrodysesthesia (1%) were infrequent. Conclusions: In previously chemotherapy treated, FGFR-inhibitor-naïve patients with iCCA harboring FGFR2 fusions, mutations, or amplifications, derazantinib showed clinically meaningful efficacy with durable objective responses, and a manageable safety profile.