Abemaciclib is indicated

• in combination with endocrine therapy (ET) (tamoxifen or an aromatase inhibitor [AI]) for the adjuvant treatment of adult patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), node-positive, early breast cancer at high risk of recurrence,
• in combination with an AI as initial endocrine-based therapy for the treatment of adult patients with HR+, HER2- advanced or metastatic breast cancer (MBC),
• in combination with fulvestrant for the treatment of adult patients with HR+, HER2- advanced or MBC with disease progression following ET, and
• as monotherapy for the treatment of adult patients with HR+, HER2- advanced or MBC with disease progression following ET and prior chemotherapy in the metastatic setting.1

Abemaciclib is an inhibitor of cyclin-dependent kinase (CDK) 4 and CDK6. These kinases are activated upon binding to D-cyclins. In estrogen receptor-positive breast cancer cell lines, cyclin D1 and CDK4/6 promote phosphorylation of the retinoblastoma protein (Rb), cell cycle progression, and cell proliferation. In vitro, continuous exposure to abemaciclib inhibited Rb phosphorylation and blocked progression from G1 into S phase of the cell cycle, resulting in senescence and apoptosis. In breast cancer xenograft models, abemaciclib dosed daily without interruption as a single agent or in combination with antiestrogens resulted in reduction of tumor size.1

Abemaciclib has not been studied in head-to-head clinical trials with other CDK 4 & 6 inhibitors.

For information on other CDK 4 and 6 inhibitors in this class, please contact the individual manufacturers of these drugs.

VERZENIO® (abemaciclib) tablets, for oral use, Lilly