Theme

MONALEESA-2: Overall Survival Results

Source
Source: Hortobagyi GN, Stemmer SM, Burris HA, et al. Overall Survival with Ribociclib plus Letrozole in Advanced Breast Cancer. N Engl J Med. 2022;386:942-50. (MONALEESA-2)

First-line Ribociclib + Letrozole extends median overall survival by over 12 months in postmenopausal patients with HR+/HER2- advanced breast cancer.

Population (N=668)
Postmenopausal
HR+/HER2- Advanced Breast Cancer
No prior systemic therapy
Study Design
Phase 3 Randomized
Ribociclib + Letrozole (n=334)
vs. Placebo + Letrozole (n=334)
Follow-Up
80 Months (Median)
Longest reported follow-up for a CDK4/6 inhibitor in this setting.
Median Overall Survival
63.9 Months
+12.5 Months Benefit

vs. 51.4 months (Placebo). Significant extension beyond 5 years.

HAZARD RATIO
0.76
24% Reduction in risk of death
(95% CI, 0.63–0.93; P=0.008)
TIME TO CHEMO
50.6 mo
Delayed by ~1 year vs Placebo (38.9 mo)
(HR 0.74)

Survival Benefit Over Time (Kaplan-Meier Estimates)

Clinical Recommendation: Preferred First-Line Standard of Care

Based on the significant extension of overall survival and delay in subsequent chemotherapy, Ribociclib + Letrozole should be adopted as a standard first-line treatment for postmenopausal patients with HR+/HER2- advanced breast cancer.

AbbreviationsQuick
CDK4/6, cyclin-dependent kinases 4 and 6; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; NE, could not be estimated; PgR, progesterone receptor.
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