Clinical Trials

AstraZeneca and Daiichi Sankyo have shared positive high-level results from the TROPION-Breast01 phase 3 trial, which showed datopotamab deruxtecan (Dato-DXd) demonstrating a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to chemotherapy in patients with inoperable or metastatic hormone receptor (HR)-positive, HER2-low or negative breast cancer.

The trial not only showed the significant improvement in PFS, but also a trend in improvement for the dual primary endpoint of overall survival (OS) compared to chemotherapy. Data for OS was not mature at the stage of interim analysis meaning the trial will continue to assess this.

The drug’s safety profile remained consistent with previous clinical trials for this indication, and no new safety signals were identified.

Susan Galbraith, executive vice president of oncology R&D at AstraZeneca, commented: “Today’s TROPION-Breast01 news is a significant development for patients with HR-positive, HER2-low or negative metastatic breast cancer whose tumours have become insensitive to endocrine therapy and who currently face poor outcomes. We are encouraged by these positive results.”

Ken Takeshita MD, global head, Oncology R&D, Daiichi Sankyo, added: “The positive topline results from TROPION-Breast01 demonstrate the potential for datopotamab deruxtecan to become an important treatment option for patients with HR-positive, HER2-low or HER2-negative breast cancer in the second-line metastatic setting. We look forward to realising the full potential of this TROP2-directed antibody drug conjugate across breast cancer subtypes through our ongoing phase 3 programme, including two trials in patients with triple-negative breast cancer.”

This data is expected to be published at an upcoming medical meeting and will be shared with the relevant health authorities.