Theme

MONALEESA-2: Overall Survival in HR+/HER2- Breast Cancer

Source
Source: Hortobagyi GN et al. Overall Survival with Ribociclib plus Letrozole in Advanced Breast Cancer. N Engl J Med. 2022;386:942-50. This publication reports results from the MONALEESA-2 phase 3 trial (NCT01958021).

Phase 3 Randomized Trial: Ribociclib + Letrozole vs. Placebo (First-Line)

Population (N=668)

Postmenopausal, HR+/HER2- Advanced Breast Cancer.

Ribociclib Arm

Ribociclib (600mg) + Letrozole. 3 weeks on / 1 week off.

Control Arm

Placebo + Letrozole. Median follow-up: 80 months.

MEDIAN OVERALL SURVIVAL
63.9 Months
+12.5 months benefit vs Placebo (51.4 mo).
Breaks the 5-year survival barrier.

Efficacy Outcomes

Relative Risk Reduction
24% Reduction
HR 0.76 (95% CI, 0.63–0.93; P=0.008)
6-Year Survival Rate
44.2% vs 32.0%
Alive at 72 months (Ribociclib vs Placebo)
Chemotherapy Delay
+11.7 Months
Delay to first subsequent chemo (HR 0.74)

Clinical Recommendation

Adopt Ribociclib + Letrozole as standard-of-care first-line treatment.

  • Significant OS benefit, breaking the 5-year barrier.
  • Substantial delay in need for cytotoxic chemotherapy.
  • Consistent safety profile with no new signals.
Standard of Care
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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