FDA approves Kisqali, a CDK4/6 inhibitor by Novartis, for early-stage breast cancer, expanding its use to include stage 2 and 3 HR positive, HER2 negative patients without positive lymph nodes. Kisqali, combined with hormone therapy, aims to reduce recurrence risk by 28.5% over endocrine therapy alone, as shown in the NATALEE trial. Common side effects include low white blood cell counts and joint pain, and it is administered for three years post-surgery.