AstraZeneca said that high-level results from the TROPION-Breast01 Phase III trial of datopotamab deruxtecan compared to investigator’s choice of chemotherapy, which previously met the dual primary endpoint of progression-free survival, did not achieve statistical significance in the final overall survival analysis in patients with inoperable or metastatic hormone receptor -positive, HER2-low or negative breast cancer previously treated with endocrine-based therapy and at least one systemic therapy. This analysis follows the positive PFS results presented at the 2023 European Society for Medical Oncology Congress which showed datopotamab deruxtecan demonstrated a statistically significant and clinically meaningful improvement in PFS. An improvement in patient-reported outcomes was also seen. The PFS data and additional results for key secondary endpoints were published this month in the Journal of Clinical Oncology. Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca, said: “The metastatic HR-positive breast cancer treatment landscape has advanced remarkably in the last several years to the benefit of patients. Based on the TROPION-Breast01 results, there is evidence of the clinical value of datopotamab deruxtecan in this setting. We will continue discussions with regulatory authorities and apply insights from these results to our clinical development programme for datopotamab deruxtecan in breast cancer.”