A study of patients receiving T-DXd (Trastuzumab Deruxtecan) for treatment of HER2+ unresectable and/or metastatic breast cancer

This study will collect real-world clinical and patient reported outcomes (PRO) and diary data from eligible patients with Human Epidermal Growth Factor Receptor 2 (HER2+) unresectable and/or metastatic Breast Cancer (mBC) receiving Trastuzumab Deruxtecan (T-DXd) in routine clinical practice.

This is a multi-center, multi-country, observational prospective study that will characterize the demographic and clinical characteristics, treatment patterns, effectiveness, tolerability and its management, and patient experience of T-DXd as second-line (2L) in the metastatic setting, or in the neoadjuvant or adjuvant setting and having developed disease recurrence during or within 6 months of completing therapy, in patients with HER2+ unresectable and/or mBC in a real-world setting. This study is planned to be conducted in several countries including but not limited to the US and Brazil and aims to enroll approximately 750 patients starting with US following the approval of T-DXd for 2L or earlier metastatic treatment. The planned duration of patient recruitment is approximately 18 months.