FPH1 (BRD-6125) induces functional proliferation of primary human hepatocytes in vitro. Human induced pluripotent stem (iPS) cells can be differentiated toward hepatocyte-like (iHep) cells, but replication is not great, and cells typically show an immature hepatic phenotype and have limited use as a renewable source of functional human hepatocytes. FPH1 induced hepatocyte colonies were used in conjunction with FH1 (BRD-K4477) to induce a more mature phenotype. Cultures treated with both FH1 and FPH1 contained larger colonies of hepatocyte-like (iHep) cells, which showed more pronounced hepatocyte morphologies with a more mature phenotype than previously obtainable.