AstraZeneca reports results from DESTINY-Breast06 Phase 3 trial

Positive high-level results from the DESTINY-Breast06 Phase III trial showed that Enhertu demonstrated a statistically significant and clinically meaningful improvement in progression-free survival, or 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, AstraZeneca announced. A statistically significant and clinically meaningful improvement in PFS was also observed in the overall trial population. A prespecified subgroup analysis showed the clinically meaningful improvement was consistent between patients with HER2-low and HER2-ultralow expression. Overall survival, or OS, 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 other secondary endpoints. Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca, said: “DESTINY-Breast06 shows that Enhertu could become a new standard of care for patients with HER2-low and HER2-ultralow metastatic breast cancer following one or more lines of endocrine therapy. These data underscore the potential for treatment with Enhertu across the spectrum of HR-positive breast cancer, further redefining the treatment of metastatic breast cancer.”