Results from a phase 3 trial showed that AstraZeneca’s oral camizestrant, in combination with a cyclin-dependent kinase 4/6 inhibitor, reduced the risk of disease progression or death by 56% compared to standard-of-care treatment in patients with advanced HR-positive breast cancer.
The SERENA-6 phase 3 trial evaluated switching to the camizestrant combination versus continuing standard-of-care treatment with an aromatase inhibitor (anastrozole or letrozole) in combination with a CDK4/6 inhibitor in the 1st-line treatment of patients with hormone receptor (HR)-positive, HER2-negative advanced breast cancer whose tumors have an emergent ESR1 mutation.
The camizestrant combination was also associated with a meaningful delay in time to deterioration in quality of life, where in an exploratory endpoint, the camizestrant combination reduced the risk of deterioration in global health status and quality of life by 47% compared with the aromatase inhibitor combination.
“Today’s news marks a pivotal moment in breast cancer care and redefines how we think about drug resistance in this type of breast cancer…This proactive approach exemplifies a new treatment strategy in oncology; by treating developing resistance before it causes disease progression and deterioration in quality of life, we can extend the benefit of 1st-line treatment to optimize patient outcomes,” said Nicholas Turner, MD, Ph.D., Professor of Molecular Oncology at The Institute of Cancer Research, London, and The Royal Marsden NHS Foundation Trust and co-principal investigator for the trial.
These results were presented during the Plenary Session at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting and simultaneously published in The New England Journal of Medicine.