An antibody-drug conjugate (ADC) composed of trastuzumab, a humanized monoclonal antibody targeting the tumor-associated antigen (TAA) epidermal growth factor receptor 2 (EGFR2; HER2; ErbB2), site-specifically conjugated, via a tumor-selective beta-glucuronide linker, to the auristatin analog and potent microtubule inhibitor monomethyl auristatin F (MMAF), with potential antineoplastic activity. Upon administration of caxmotabart entudotin, the trastuzumab moiety targets and binds to HER2 expressed on tumor cells. Upon binding, internalization and linker cleavage, MMAF is released. MMAF binds to and inhibits tubulin polymerization, which results in G2/M phase arrest and tumor cell apoptosis. HER2, a tyrosine kinase receptor, is overexpressed by many cancer cell types.