Patritumab-deruxtecan is a new-generation HER3-directed antibody–drug conjugate (U3-1402) that constitutes a immunoglobulin G1 mAb patritumab linked to a topoisomerase I Inhibitor cytotoxic payload by a tetrapeptide, cleavable linker, which is specific to a particular tumor. Here, ERBB3 is linked to neoplasm.