MONALEESA-2 Update

Source

Source: Hortobagyi GN, Stemmer SM, Burris HA, et al. Updated results from MONALEESA-2, a phase III trial of first-line ribociclib plus letrozole versus placebo plus letrozole in hormone receptor-positive, HER2-negative advanced breast cancer. Ann Oncol. 2018;29(7):1541-1547.

Ribociclib + Letrozole Sustains Dominant 25.3-Month PFS in First-Line Advanced Breast Cancer

Median PFS

25.3 months

vs. 16.0 months (Placebo)
+9.3 Months Gain

Study Architecture

N=668 Postmenopausal, HR+/HER2-
Phase III, Randomized (1:1)
Intervention: Ribociclib + Letrozole
Control: Placebo + Letrozole
Follow-up: 26.4 months median

Efficacy

Hazard Ratio: 0.568

43% Risk Reduction

Safety

Grade 3/4 Neutropenia

52.4%

vs. 1.2% (Placebo)

Manageable: Only 8.1% permanent discontinuation rate.

Standard First-Line Therapy

With a 9.3-month PFS advantage, Ribociclib + Letrozole is a priority regimen. Implement standard monitoring (CBC, ECG) to manage toxicity.

AbbreviationsQuick

AE, adverse event; AI, aromatase inhibitor; CI, confidence interval; ctDNA, circulating tumor DNA; ECG, electrocardiogram; ECOG PS, Eastern Cooperative Oncology Group performance status; HER2–, human epidermal growth factor receptor 2-negative; HR+, hormone receptor-positive; LFT, liver function test; NR, not reached; ORR, overall response rate; OS, overall survival; PFS, progression-free survival; QTcF, QT interval corrected by Fridericia’s formula; RECIST, Response Evaluation Criteria in Solid Tumors; RTK, receptor tyrosine kinase; TAM, tamoxifen.

Bibliography1

Hortobagyi GN, Stemmer SM, Burris HA, et al. Updated results from MONALEESA-2, a phase III trial of first-line ribociclib plus letrozole versus placebo plus letrozole in hormone receptor-positive, HER2-negative advanced breast cancer. Ann Oncol. 2018;29(7):1541-1547. (DOI: 10.1093/annonc/mdy155)