Information H3B-6527 H3B-6527 is a highly selective covalent FGFR4 inhibitor with an IC50 value of Targets FGFR4 (Cell-free assay) In vitro H3B-6527 shows robust inhibition of the target kinase FGFR4 with an IC50 value of 10,000, and >10,000 nmol/L, respectively. H3B-6527 inhibits FGFR4 signaling, proliferation, and leads to apoptosis in a HCC cell line (Hepatocellular carcinoma). Treatment on Hep3B cells leads to robust activation of caspase-3/7, an apoptotic marker, in a concentration-dependent manner, indicating FGFR4 inhibition by H3B-6527 leads to cell death in HCC cell lines. H3B-6527 has the selectivity and the selective dependence on FGFR4 across cancer types. In vivo In the Hep3B human HCC xenograft mouse model, H3B-6527 shows dose-proportional plasma exposures and greater than dose-proportional tumor exposures within the dose range evaluated (30, 100, and 300 mg/kg). The H3B-6527 pharmacodynamic response as measured by CYP7A1 mRNA and pERK1/2 protein levels is dose dependent, with higher doses leading to sustained responses. Oral treatment of H3B-6527, twice daily, inhibits xenograft growth in a dose-dependent manner in nude mice, with the 300 or 100 mg/kg twice daily, significantly inhibiting tumor growth in both Hep3B subcutaneous and orthotopic xenograft model and causing tumor regressions in the subcutaneous xenograft model. Palbociclib can enhance H3B-6527 efficacy and promote tumor regression in JHH-7 model where H3B-6527 as a single agent can only lead to tumor stasis. Cell Research(from reference) Cell lines：Hep3B cells Concentrations：100 and 300 nmol/L Incubation Time：0.5, 1, 2, 4, 8, and 24 hours