KATHERINE
Trastuzumab Emtansine for Residual Invasive HER2-Positive Breast Cancer
Patient / Population Intervention / Exposure Comparison Outcome
In 1,486 patients with HER2+ early breast cancer and residual invasive disease after neoadjuvant taxane + trastuzumab, adjuvant trastuzumab emtansine (T-DM1) reduced invasive disease-free survival events compared with trastuzumab.
N
1,486
Design
Open-label RCT
Endpoint
Invasive disease-free survival
Relevance
2
Result3-yr iDFS 88.3% vs 77.0% (HR 0.50). 8.4-yr OS HR 0.66.
von Minckwitz G, et al. N Engl J Med. 2019;380(7):617-628; Geyer CE, et al. N Engl J Med. 2025;392(3):249-257. 10.1056/NEJMoa1814017
Discussion & critique
Defined post-neoadjuvant escalation in HER2+ early breast cancer with residual disease as standard of care.