Duligotuzumab demonstrated superior activity compared with mono-specific EGFR- or HER3-targeting antibodies in the non-clinical FaDu SCCHN model (16), as well as in human xenograft models derived from SCCHN and NSCLC tumors with acquired resistance to EGFR inhibitors (17). Here, ERBB3 is linked to head and neck squamous cell carcinoma.