A Randomized, Double-Blind, Placebo-Controlled, Phase 3 Study to Compare the Efficacy of Abemaciclib Plus Fulvestrant to Placebo Plus Fulvestrant in Participants With HR+, HER2-, Advanced or Metastatic Breast Cancer Following Progression on a CDK4 & 6 Inhibitor and Endocrine Therapya
Hormone-receptor-positive (HR+), HER2-negative (HER2-) locally advanced or metastatic breast cancer
Radiologic evidence of disease progression or recurrence either:
On treatment with a cyclin-dependent kinase 4 and 6 (CDK4/6) with aromatase inhibitor (AI) as initial therapy for advanced disease, or
On/after treatment with a CDK4/6 inhibitor plus endocrine therapy (ET) administered as adjuvant therapy for early-stage breast cancer
Must be deemed appropriate for treatment with ET
If female, have a postmenopausal status by natural or surgical means or by ovarian function suppression
Measurable disease and/or nonmeasurable disease as defined by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1
Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
Adequate renal, hematologic, and hepatic organ function
Able to swallow capsules/tablets
Key Exclusion Criteria
Visceral crisis, lymphangitic spread, or leptomeningeal carcinomatosis
Symptomatic or untreated central nervous system metastasis
Received any systemic therapy between disease recurrence/progression and study screening
Received more than one line of therapy for advanced or metastatic disease
Prior chemotherapy for metastatic breast cancer (MBC)
Prior treatment with fulvestrant, any investigational estrogen receptor (ER)-directed therapy (including selective ER degraders [SERDs] and non-SERDs), any PI3K, mTOR, or AKT inhibitor
a
This clinical trial is being conducted globally.
b
Administered orally.
c
Administered intramuscularly.
For information on trial enrollment, locations, and more, call
1-800-545-5979.