The potential of dual targeting in the adjuvant setting is being investigated in the ongoing APHINITY trial [Study of Pertuzumab in Addition to Chemotherapy and Herceptin (Trastuzumab) as Adjuvant Therapy in Patients with HER2-Positive Primary Breast Cancer], which is comparing the dual targeting of pertuzumab plus trastuzumab with trastuzumab alone following adjuvant chemotherapy. Here, ERBB2 is linked to breast cancer.