HER2-(Ultra)Low Expressing Breast Cancer

Trastuzumab deruxtecan (T-DXd) as monotherapy is indicated for the treatment of adult patients with unresectable or metastatic HER2-low breast cancer who have received prior chemotherapy in the metastatic setting or developed disease recurrence during or within 6 months of completing adjuvant chemotherapy. Based on the extended therapeutic indication of Trastuzumab deruxtecan (Enhertu®), a new patient population will be enrolled, comprising adult patients with unresectable or metastatic HR-positive, HER2-low, or HER2-(ultra)low breast cancer who have received at least one endocrine therapy in the metastatic setting and are not considered suitable for endocrine therapy as the next line of treatment.