Here we describe the design and validation of the DN30 mAb humanized one-arm form (hOA-DN30), and present data demonstrating its robust anti-proliferative and tumor growth-inhibitory effects in multiple MET-addicted cell lines and xenograft cancer models, as well as its favorable pharmacokinetics and safety profile in non-human primates. The gene discussed is MATN3; the disease is neoplasm.