An antibody drug conjugate (ADC) containing a fully human monoclonal antibody AGS-22 targeting the cell adhesion molecule nectin-4 and conjugated, via a proprietary enzyme-cleavable linker, to the cytotoxic agent monomethyl auristatin E (MMAE) (AGS-22M6E), with potential antineoplastic activity. The monoclonal antibody moiety of AGS-22M6E selectively binds to nectin-4. After internalization and proteolytic cleavage, MMAE binds to tubulin and inhibits its polymerization, which results in G2/M phase arrest and induces apoptosis in nectin-4 overexpressing tumor cells. Nectin-4, a tumor associated antigen belonging to the nectin family, is overexpressed in a variety of cancers, including breast, bladder, lung and pancreatic cancer.