Treatment with Verzenio (abemaciclib) plus endocrine therapy for two years demonstrated a statistically significant and clinically meaningful improvement in overall survival compared to endocrine therapy alone in HR+, HER2-, node-positive, high-risk early breast cancer. The seven-year landmark analysis of monarchE reinforces two years of Verzenio plus endocrine therapy as the standard of care for this high-risk population, with sustained invasive disease-free survival and distant relapse-free survival benefits persisting beyond the treatment period.
Study Design & Population:
- monarchE was a global, randomized, open-label, two-cohort, multicenter Phase 3 clinical trial
- Enrolled 5,637 adults with HR+, HER2-, node-positive early breast cancer at high risk of recurrence across more than 600 sites in 38 countries
- Cohort 1 (n=5,120, FDA-approved population): Patients with 4+ positive nodes OR 1-3 positive nodes plus tumors ≥5 cm or Grade 3
- Cohort 2 (n=517): Patients with 1-3 positive nodes and Ki-67 score ≥20%
- Randomized 1:1 to receive Verzenio 150 mg twice daily plus standard-of-care adjuvant endocrine therapy versus endocrine therapy alone for 2 years
- Endocrine therapy continued for at least 5 years if deemed medically appropriate
- Primary endpoint: invasive disease-free survival (IDFS); overall survival was a key secondary endpoint
Key Findings:
- Verzenio plus endocrine therapy achieved statistically significant overall survival benefit in the seven-year landmark analysis
- Sustained invasive disease-free survival (IDFS) benefit maintained at seven years
- Sustained distant relapse-free survival (DRFS) benefit maintained at seven years
- Treatment effect remained consistent and durable across all endpoints
- Only adjuvant study designed to investigate a CDK4/6 inhibitor specifically in a node-positive, high-risk early breast cancer population
- All patients completed or discontinued the two-year course of Verzenio at time of analysis
Clinical Implications:
- Achieving statistically significant overall survival benefit with just two years of therapy reinforces Verzenio’s differentiated profile in high-risk HR+, HER2- early breast cancer
- Results support continued use of two years of Verzenio plus endocrine therapy as standard of care for HR+, HER2-, node-positive, high-risk early breast cancer patients
- Verzenio is the first CDK4/6 inhibitor approved to treat node-positive, high-risk early breast cancer
- NCCN recommends consideration of two years of abemaciclib (Verzenio) added to endocrine therapy as a Category 1 treatment option in the adjuvant setting
- Persistent and deepening benefit observed beyond the two-year treatment period, suggesting lasting disease control
Limitations:
- Overall safety profile unchanged and consistent with previous reports; no new safety signals identified
- Detailed results to be presented at future medical meeting and submitted for peer-reviewed publication
- Specific numerical data for overall survival benefit not disclosed in this announcement
- Results will be discussed with regulatory bodies for potential label implications
