Novartis announced results of the final overall survival (OS) analysis of the Phase III MONALEESA-2 study, which evaluated Kisqali® (ribociclib) in combination with letrozole compared to placebo plus letrozole in postmenopausal women with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced or metastatic breast cancer with no prior systemic treatment for advanced disease. These data will be presented as a late-breaker oral presentation at the European Society for Medical Oncology (ESMO) Congress 2021 on September 19 (#LBA17). Kisqali in combination with letrozole met its key secondary endpoint of OS, demonstrating a statistically significant and clinically meaningful improvement in survival (median 63.9 vs. 51.4 months; HR=0.76; 95% CI: 0.63-0.93; p=0.004). The analysis found that after a median follow-up of over six and a half years, the longest for any CDK4/6 inhibitor trial to date, the improvement in the median OS was over one year. MONALEESA-2 showed that after five years, patients treated with Kisqali in combination with letrozole had more than a 50% chance of survival (52.3% vs. 43.9%; 95% CI: 46.5-57.7 vs. 38.3-49.4). In MONALEESA-2, a 12-month delay in time to chemotherapy was observed with Kisqali (median 50.6 vs. 38.9 months; HR=0.74; 95% CI: 0.61-0.91) compared to those taking letrozole alone. With this longer follow-up, no new safety signals were observed; adverse events were consistent with previously reported Phase III trial results for Kisqali.