In the present work, we show that, consistently with previous data obtained with biotinylated anti-EGFR antibodies [7, 8], AvidinOX anchorage significantly enhances in vitro anti-tumor activity of biotinylated anti-ErbB2 antibodies Trastuzumab (bTrast) or Pertuzumab (bPert). The gene discussed is ERBB2; the disease is neoplasm.