Bemcentinib (R428) is a selective and orally active Axl inhibitor with an IC50 of 14 nM. Bemcentinib retards cancer cell migration and invasion. Bemcentinib exhibits >100-fold selectivity for Axl versus Abl and 50- and >100-fold selectivity over TAM family kinases Mer and Tyro3, respectively, in cells. Bemcentinib blocks tumor spread and prolongs survival in models of metastatic breast cancer[1][2].