Emerging Clinical Strategies in Cholangiocarcinoma: A Review on Targeted Therapy and Immunotherapy | RISE Research

This review paper maps the rapid paradigm shift in clinical management of cholangiocarcinoma (CCA), a rare, highly heterogeneous, and aggressive biliary tract cancer with five-year survival rates below 20% that is typically diagnosed at an advanced, unresectable stage. The paper contrasts two major emerging treatment approaches: precision-targeted therapies aimed at specific molecular alterations, such as FGFR2 fusions (present in 10-16% of intrahepatic CCA cases, targetable with approved drugs like pemigatinib) and IDH1 mutations (present in 20-25% of cases, targetable with ivosidenib), which produce deep but narrow tumor responses restricted to the 15-20% of patients with these specific alterations; versus large-scale chemoimmunotherapy trials, TOPAZ-1 (durvalumab plus chemotherapy, 685 patients) and KEYNOTE-966 (pembrolizumab plus chemotherapy, 1,069 patients), which extended median overall survival to roughly 12.7-12.8 months across a broad, unselected patient population, offering durability rather than depth of response. The review identifies several structural barriers hindering further progress: the logistical difficulty of obtaining sufficient tumor tissue for genomic testing given the biliary tract's deep anatomical location, the rarity of specific molecular subgroups making trial recruitment difficult (one IDH1-inhibitor trial required 49 sites across 6 countries), and the historical practice of pooling distinct anatomical CCA subtypes (intrahepatic, perihilar, distal) into single clinical trials, which obscured meaningful differences in tumor biology and drug sensitivity. The paper also discusses pre-clinical strategies designed to penetrate CCA's notoriously dense, immunosuppressive desmoplastic stroma, a key driver of chemoresistance and post-surgical recurrence. The review concludes that improving CCA outcomes depends on overcoming acquired resistance to targeted therapies, democratizing access to comprehensive genomic profiling, and adopting adaptive, molecularly guided clinical trial designs, arguing these steps could transform CCA from a highly lethal malignancy into a more manageable chronic disease.