This study will examine trastuzumab deruxtecan (T-DXd) versus trastuzumab emtansine (T-DM1) in patients with HER2-positive primary BC who have residual invasive disease in breast or axillary lymph nodes with higher risk of recurrence, which includes patients who were inoperable at disease presentation or had pathological node-positive status after neoadjuvant therapy.~The primary objective is to compare invasive disease-free survival (IDFS) between T-DXd and T-DM1 treatment arms in this population. The key secondary objective of the study is to evaluate disease-free survival (DFS).
Patients with HER2-positive primary breast cancer (BC) who do not achieve complete response after appropriate neoadjuvant therapy are at higher risk of disease recurrence. More effective treatment options are needed for this patient population. This study will examine the efficacy and safety of trastuzumab deruxtecan (T-DXd) compared with trastuzumab emtansine (T-DM1) in high-risk patients with residual invasive breast cancer following neoadjuvant therapy.