BLU-554 is a potent and selective inhibitor of fibroblast growth factor receptor 4 (FGFR4), primarily investigated for its role in targeted cancer therapy. It shows significant promise in treating hepatocellular carcinoma (HCC), especially in tumors driven by the activation of the FGFR4 signaling pathway, often associated with elevated levels of FGF19. By blocking FGFR4 activity, BLU-554 inhibits tumor cell proliferation and induces apoptosis, leading to reduced tumor growth in preclinical models. It has advanced into clinical trials to evaluate its efficacy and safety in patients with advanced liver cancer who have limited treatment options. Its development represents a precision medicine approach, aiming to match therapy to the molecular profile of the tumor.