SONIA Trial Finds No Overall Survival Benefit for First-Line CDK4/6 Inhibitors in Advanced Breast Cancer
The SONIA trial found no overall survival benefit for first-line CDK4/6 inhibitors versus second-line use in advanced HR+/HER2- breast cancer. Median survival was 47.9 vs 48.1 months, though post hoc analysis suggested benefit in premenopausal patients. First-line treatment was associated with more severe adverse events.