AstraZeneca breast cancer drug shows 'significant' survival rates

Drugmaker AstraZeneca said its Enhurtu breast cancer drug had demonstrated a "statistically significant and clinically meaningful improvement" in survival a phase three trial versus chemotherapy.

AstraZeneca stated DESTINY-Breast04 met its primary endpoint, where Enhertu demonstrated "superior" PFS in previously treated patients with HR-positive HER2-low metastatic breast cancer compared to the standard-of-care chemotherapy.

The company, which is working on the drug with Japan's Daiichi Sankyo, said Enhertu prolonged survival and slowed the progression of metastatic breast cancer in women with low levels of a protein known as HER2.

Enhertu also met its key secondary endpoint of progression-free survival in patients with HER2-low metastatic breast cancer regardless of hormone receptor status and also met its key secondary endpoints of overall survival in patients with HR-positive disease and in patients regardless of hormone receptor status at interim analysis.

Susan Galbraith, AstraZeneca's executive vice-president of oncology R&D said: "Today's historic news from DESTINY-Breast04 could reshape how breast cancer is classified and treated. A HER2-directed therapy has never-before shown a benefit in patients with HER2-low metastatic breast cancer."

"These results for Enhertu are a huge step forward and could potentially expand our ability to target the full spectrum of HER2 expression, validating the need to change the way we categorise and treat breast cancer."