Key clinical point: Replacing trastuzumab+taxane with trastuzumab emtansine (T-DM1) did not improve survival in high-risk human epidermal growth factor receptor 2 (HER2)-positive early breast cancer (BC).
Major finding: The risk for invasive disease-free survival was not significantly different between trastuzumab+taxane+pertuzumab and T-DM1+pertuzumab arms in the overall population (stratified hazard ratio [sHR], 0.98; 95% CI, 0.72-1.32) and the node-positive subpopulation (sHR, 0.97; 95% CI, 0.71-1.32) along with similar rates of grade 3 or higher and serious adverse events.
Study details: Findings are from the phase 3 KAITLIN study, including 1,846 patients with HER2-positive early BC who were randomly assigned to receive T-DM1+pertuzumab or trastuzumab+taxane+pertuzumab after surgery and anthracycline chemotherapy.
Disclosures: This study was supported by F. Hoffmann-La Roche Ltd. The authors declared serving as consultant, speaker, and/or receiving honorarium, funding, and travel expense from several sources. Some authors were employed and/or held stocks in various sources.
Source: Krop IE et al. J Clin Oncol. 2021 Dec 10. doi: 10.1200/JCO.21.00896 .