AstraZeneca's new experimental drug, camizestrant, has shown substantial promise in reducing the risk of breast cancer progression when used as part of a treatment guided by blood tests. This was revealed in a study presented at the American Society of Clinical Oncology meeting, which involved a substantial cohort of 3,256 patients who have advanced hormone receptor-positive, HER2-negative breast cancer, according to Reuters.

The trial, focusing on a specific segment of 315 patients with ESR1 mutations, found noteworthy results. These mutations are known indicators of resistance to therapy. Patients in the trial were randomly placed into two groups: one group received camizestrant combined with a CDK4/6 inhibitor, while the other group continued with the standard breast cancer treatment. Significantly, patients on the camizestrant regimen experienced a median progression-free survival rate of 16 months, compared to just 9.2 months for those sticking with existing treatments—a 56% reduction in the risk of progression.

This study not only highlights the effectiveness of camizestrant but also underscores a new paradigm for treatment, using liquid biopsy blood tests to guide clinical decisions before tumors become detectable via conventional imaging methods. This approach represents a significant potential advancement in how advanced breast cancer can be managed and treated, offering earlier and more effective intervention options for patients.