The FDA approved adjuvant ribociclib (Kisqali) plus an aromatase inhibitor for HR-positive, HER2-negative stage II and III early breast cancer with high recurrence risk, based on NATALEE trial data showing improved invasive disease-free survival. The combination achieved 3-year iDFS rates of 90.4% vs 87.1% with endocrine therapy alone, with benefits sustained over 44.2 months of follow-up.