Key clinical point: Adjuvant abemaciclib plus endocrine therapy (ET) reduced the risk for recurrence and demonstrated a favorable safety profile in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) early breast cancer (BC) at a high risk for recurrence.
Major finding: Abemaciclib+ET helped sustain the invasive disease-free survival benefit compared with only ET even at 42 months of median follow-up (hazard ratio 0.664; nominal P < .0001). Although the frequency of grade ≥3 adverse events was higher with abemaciclib+ET (49.9%) vs ET alone (16.9%), it was considered manageable and acceptable for patients with high-risk early BC.
Study details : Findings are from the phase 3, monarchE trial including 5637 patients with HR+/HER2−, node-positive, early BC who were randomly assigned to receive adjuvant ET with or without abemaciclib.
Disclosures: This study was funded by Eli Lilly. Five authors declared being employees and shareholders of Eli Lilly, and the other authors reported ties with several sources, including Eli Lilly.
Source: Johnston SRD et al on behalf of the monarchE Committee Members. Abemaciclib plus endocrine therapy for hormone receptor-positive, HER2-negative, node-positive, high-risk early breast cancer (monarchE): Results from a preplanned interim analysis of a randomised, open-label, phase 3 trial. Lancet Oncol. 2022 (Dec 6). Doi: 10.1016/S1470-2045(22)00694-5