An antibody-drug conjugate (ADC) composed of a monoclonal antibody against the tumor-associated antigen (TAA) receptor tyrosine kinase-like orphan receptor 1 (ROR1) linked to an as of yet undisclosed cytotoxic agent, with potential antineoplastic activity. Upon intravenous administration, the monoclonal antibody moiety of zilovertamab vedotin targets and binds to ROR1 expressed on tumor cells. Upon binding and internalization, the cytotoxic agent is released and kills the ROR1-expressing cancer cells, through an as of yet unknown mechanism of action. ROR1, also known as neurotrophic tyrosine kinase, receptor-related 1 (NTRKR1), is expressed during embryogenesis and by certain leukemias. It plays key roles in tumor cell proliferation and survival.