Of all treated patients, 17 (31%) achieved stable disease (SD) as best response, including one patient with SCCHN who achieved a long-lasting SD >40 weeks, one with HER2-positive metastatic breast cancer who achieved SD for approximately 32 weeks, and one trastuzumab-naive gastric cancer patient with an unconfirmed partial response at Day 53 (Cycle 2 Day 25) who subsequently experienced disease progression at Day 81 (Cycle 3 Day 25). This evidence concerns the gene ERBB2 and head and neck squamous cell carcinoma.