AstraZeneca and Daiichi Sankyo’s ENHERTU improves PFS in HER2-low

Positive high-level results from the DESTINY-Breast06 Phase III trial showed that ENHERTU or fam-trastuzumab deruxtecan-nxki,demonstrated a statistically significant and clinically meaningful improvement in progression-free survival PFS compared to standard-of-care chemotherapy in the primary trial population of patients with HR-positive, HER2-low metastatic breast cancer following one or more lines of endocrine therapy. A statistically significant and clinically meaningful improvement in PFS was also observed in the overall trial population (patients with HER2-low and HER2-ultralow (defined as IHC 0 with membrane staining; IHC greater than0less than1+) metastatic breast cancer). A prespecified subgroup analysis showed the clinically meaningful improvement was consistent between patients with HER2-low and HER2-ultralow expression. Overall survival data were not mature at the time of the analysis; however, ENHERTU showed an early trend towards an OS improvement versus standard-of-care chemotherapy in patients with HER2-low metastatic breast cancer and in the overall trial population. The trial will continue as planned to further assess OS and