Theme

MONALEESA-2: First-Line Ribociclib Extension of Overall Survival Exceeds One Year

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 Clinical Trial (NCT01958021).

Advanced HR+/HER2- Breast Cancer • Median Follow-up: 6.6 Years (Longest reported for CDK4/6i)

Population
N = 668
Postmenopausal
HR+/HER2- Advanced
Design
Phase 3
Randomized, Double-blind
Placebo-controlled
Intervention
Ribociclib + Letrozole
vs. Placebo + Letrozole
(1:1 Randomization)
Follow-Up
6.6 Years
Median (80 months)

Median Overall Survival

63.9
Months
+12.5 Months Gain

vs. 51.4 Months (Placebo)
HR 0.76 (P=0.008)

Efficacy Outcomes

Survival Advantage 24% relative reduction in risk of death. Absolute improvement of 12.5 months.
Long-Term Durability At 6 years, 44.2% of Ribociclib patients estimated alive vs. 32.0% (placebo).
Delayed Chemo Median time to first chemo extended to 50.6 months (vs 38.9), preserving QoL.

Recommendation: Prioritize as Standard-of-Care

With median OS exceeding 5 years—a clinically historic benchmark—Ribociclib + Letrozole is recommended as a preferred 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.
Bibliography8
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  2. Hortobagyi GN, Stemmer SM, Burris HA, et al. Ribociclib as first-line therapy for HR-positive, advanced breast cancer. N Engl J Med 2016;375:1738-48.
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