AZ 14145845, a potent and highly selective dual Mer/Axl kinase inhibitor (pIC50 = 7 nM and 7.8 nM in pAxl and pMer, respectively), demonstrates significant efficacy in reducing tumor growth in a dose-dependent manner within the Mer and Axl kinase Ba/F3 tumor xenograft model in vivo. When combined with anti-PD1 antibodies and ionizing radiation, this compound enhances survival rates in mice bearing MC38-derived tumors. Additionally, AZ 14145845 is orally bioavailable.