CDK4/6 Inhibitor
Not Enrolling
A Randomized, Open-Label, Phase 3 Study of Abemaciclib Combined With Standard Adjuvant Endocrine Therapy Versus Standard Adjuvant Endocrine Therapy Alone in Patients With High-Risk, Node-Positive, Early-Stage, Hormone-Receptor-Positive, Human Epidermal Receptor 2-Negative Breast Cancer*

NCT03155997 show modal icon
Key Inclusion Criteria
  • Hormone-receptor-positive (HR+), HER2-negative, node-positive, early-stage resected invasive breast cancer without evidence of distant metastases
  • Underwent definitive surgery of the primary breast tumor(s) within 16 months of randomization
  • Availability of tumor tissue from breast or lymph node for biomarker analysis prior to randomization
  • Pathologic axillary lymph node involvement with at least one of the following:
    • Four or more positive axillary lymph nodes
    • Tumor size of at least 5 cm
    • Grade 3 tumor defined as at least 8 points on the Bloom-Richardson grading system
    • Ki-67 index by central analysis of ≥20% on untreated breast tissue
  • Up to 12 weeks of endocrine therapy following the last nonendocrine therapy
  • Recovery (grade ≤1) from the acute effects of chemotherapy and radiotherapy, and surgical side effects following definitive breast surgery
  • Female (regardless of menopausal status) or male ≥18 years of age, or per local regulations
  • Negative blood pregnancy test and must agree to use highly effective contraceptive methods
  • Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
  • Adequate organ function
  • Able to swallow oral medications
Key Exclusion Criteria
  • Metastatic disease (including contralateral axillary lymph nodes) or lymph node-negative breast cancer
  • Inflammatory breast cancer
  • History of breast cancer (except ipsilateral ductal carcinoma in situ treated by locoregional therapy alone) ≥5 years prior to study entry
  • History of any other cancer (except nonmelanoma skin cancer or carcinoma in situ of the cervix) unless in complete remission with no therapy for a minimum of 5 years, or at low risk of recurrence if diagnosed within the last 5 years
  • Pregnant or breastfeeding
  • Previous treatment with any cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor
  • Currently receiving concurrent exogenous hormone therapy
  • Previously received endocrine therapy for breast cancer prevention
  • Serious preexisting medical conditions as judged by the investigator 
  • History of syncope of cardiovascular etiology, ventricular arrhythmia of pathological origin, or sudden cardiac arrest
  • History of venous thromboembolic event
  • Active systemic infections, or fungal or detectable viral infections requiring systemic therapy
  • Received an experimental treatment in a clinical trial within the last 30 days or 5 half-lives, whichever is longer
This clinical trial is being conducted globally. 
Abemaciclib is administered PO.
Standard adjuvant endocrine therapy is administered according to label instructions.
For information on trial enrollment, locations, and more, call 1-800-545-5979.