A soluble fusion protein comprised of the extracellular domain of the receptor tyrosine kinase (RTK) AXL (UFO) fused to a human immunoglobulin G1 (IgG1) Fc domain, with potential antineoplastic activity. Upon administration, batiraxcept selectively binds to growth arrest-specific protein 6 (GAS6), the endogenous ligand for AXL. This may inhibit GAS6/AXL-mediated signaling, which plays a key role in tumor cell proliferation, survival, invasion and metastasis, as well as immune evasion and resistance to other anticancer agents. AXL, a member of the Tyro3, AXL and Mer (TAM) family of RTKs, is overexpressed by many tumor cell types and its expression is associated with drug resistance and poor prognosis.