Pharmacist Medication Insights: Abemaciclib (Verzenio) for Breast Cancer

In October 2021, the FDA approved abemaciclib (Verzenio) in combination with endocrine therapy for the adjuvant treatment of adult patients with hormone receptor (HR)–positive, human epidermal growth factor receptor 2 (HER2)-negative, node-positive, early breast cancer at high risk of recurrence and a Ki-67 score of 20% or higher, as determined by an FDA-approved test. The FDA also approved the Ki-67 IHC MIB-1 pharmDx (Dako Omnis) assay as a companion diagnostic for selecting eligible patients for this indication of abemaciclib.

The approval was based on the results of the phase 3 monarchE (NCT03155997) trial, in which abemaciclib was evaluated among patients with HR–positive, HER2-negative, node-positive, resected, early breast cancer with clinical and pathological features consistent with a high risk of disease recurrence. Study participants were randomized 1:1 to receive 2 years of either abemaciclib plus physician’s choice of standard endocrine therapy (ET) or standard ET alone.