ASCO 2025: Redefining First-Line Therapy in HER2+ Breast Cancer with T-DXd and Pertuzumab

In this MEDtalk, Dr. Sara Tolaney, MD, MPH, from Dana-Farber Cancer Institute, presents results from the phase 3 DESTINY-Breast 09 trial, presented at ASCO 2025. The combination of trastuzumab-deruxtecan and pertuzumab led to a significant and clinically meaningful improvement in progression-free survival, 40.7 months compared to 26.9 months with standard taxane-based therapy including trastuzumab and pertuzumab, corresponding to a hazard ratio of 0.56. The regimen was well tolerated and showed consistent benefit across patient subgroups, supporting its potential as a new first-line standard for metastatic HER2-positive breast cancer.