Key clinical point: The addition of abemaciclib to endocrine therapy (ET) demonstrated robust treatment benefits regardless of menopausal status in women with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−), high-risk early breast cancer (BC).
Major finding: Abemaciclib+ET significantly improved invasive disease-free survival (iDFS; hazard ratio 0.785; nominal P = .0268 ) in postmenopausal women with HR+/HER2− BC and led to even greater iDFS improvement (hazard ratio 0.578; P < .0001) in premenopausal women. No new safety events were reported.
Study details : Findings are from an exploratory analysis of the monarchE trial including 5637 patients with HR+/HER2−, node-positive, high-risk early BC who were randomly assigned to receive standard of care ET with/without adjuvant abemaciclib, of which 43.5% and 56.4% of patients were premenopausal and postmenopausal, respectively.
Disclosures: This study was funded by Eli Lilly and Company. Four authors declared being employees and shareholders of Eli Lilly. The other authors reported ties with several sources, including Eli Lilly.
Source: Paluch-Shimon S et al, on behalf of the monarchE investigators. Efficacy and safety results by menopausal status in monarchE: adjuvant abemaciclib combined with endocrine therapy in patients with HR+, HER2−, node-positive, high-risk early breast cancer. Ther Adv Med Oncol. 2023 (Feb 3). Doi: 10.1177/17588359231151840