Trastuzumab Deruxtecan May Become New Standard of Care After ≥1 Endocrine-Based Therapy for Patients with HER2-low and -ultralow, HR+ mBC

Giuseppe Viale presented new results from the DESTINY-Breast06 trial at ESMO 2024. The results showed that 94% of locally identified HER2-low cases were confirmed by central testing, and 64% of samples classified as HER2-zero locally actually had some HER2 expression. These findings suggest that patients with even low HER2 expression may be eligible for T-DXd treatment, which has proven effective regardless of HER2-low or ultra-low status.