In the phase 3 DESTINY-Breast02 trial, #Trastuzumab deruxtecan (T-DXd) improved the PFS and OS in patients with HER2-positive metastatic breast cancer as a 3rd line of therapy after failure on TDM-1.

In this updated report of the phase III randomized trial that was presented at the SABCS2022 by Krop, 608 eligible patients with HER2positive metastatic breast cancer who progressed on at least 2 prior lines (including T-DM1) were randomized (2:1) to either T-DXd (n = 406) or a physician choice of combination therapy (TPC) of capecitabine with either trastuzumab or lapatinib (n= 202). Primary endpoint was PFS and secondary endpoints included overall survival, response rate, and safety.

Updated results showed statistically significant and clinically meaningful improvement in the PFS and OS. Median PFS was 17.8 months for patients with T-DXd versus 6.9 months for patients with TPC (HR=0.35). Additionally, median OS was 39.2 months versus 26.5 months in the T-DXd and TPC arms, respectively (HR=0.66).