Phase III MONALEESA-2 trial for Kisqali in HR+/HER2- breast cancer published in NEJM.- Novartis

The data show more than a 12 month increase in overall survival for Kisqali plus letrozole compared to letrozole alone, in postmenopausal women with hormone-receptor positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) advanced or metastatic breast cancer. MONALEESA-2 overall survival data were first presented at the European Society for Medical Oncology (ESMO) Congress in September 2021. The NEJM publication includes additional analyses substantiating the longest median overall survival benefit ever reported for HR+/HER2- advanced breast cancer patients, supporting the use of Kisqali combination therapy as a first-line treatment.

The NEJM publication includes the following: i.median overall survival among patients in the Kisqali plus letrozole group was over five years (63.9 months) compared to four years (51.4 months) for the placebo group (HR=0.76; 95% CI: 0.63-0.93; two-sided p=0.008). ii. Patients who received Kisqali plus letrozole as first-line therapy saw a 24% reduction in risk of death compared to those receiving letrozole alone.iii. The overall survival benefit with Kisqali plus letrozole continued to increase over time, with the survival rate of patients receiving Kisqali plus letrozole at 52.3% at five years (8.4% higher than letrozole alone) and 44.2% at six years (12.2% higher than letrozole alone).iv. Fewer patients in the Kisqali plus letrozole group received subsequent treatment with any-line CDK4/6 inhibitor therapy (34.4% for letrozole alone compared to 21.7%); the significant overall survival benefit with Kisqali plus letrozole was consistent after adjusting for subsequent treatment with any-line CDK4/6 inhibitors. v. Patients on Kisqali plus letrozole compared to those on letrozole alone experienced an additional one-year delay to subsequent chemotherapy (50.6 months compared to 38.9 months in the placebo group).vi. This study has the longest reported follow-up for any CDK4/6 inhibitor clinical trial to date with a median of 80 months, with no new safety signals emerging; adverse events were consistent with previously reported Phase III trial results for Kisqali.

See: "Overall Survival with Ribociclib plus Letrozole in Advanced Breast Cancer." Gabriel N. Hortobagyi et al. N Engl J Med 10 March 2022; 386:942-950 DOI: 10.1056/NEJMoa2114663