abemaciclib + anastrozole

Abemaciclib + anastrozole is a combination therapy consisting of a selective CDK4/6 inhibitor (abemaciclib) and a non-steroidal aromatase inhibitor (anastrozole). Abemaciclib works by blocking the action of cyclin-dependent kinases 4 and 6, which regulate cell cycle progression from G1 to S phase, thereby inhibiting tumor cell proliferation. Anastrozole reduces estrogen production by inhibiting the aromatase enzyme, which converts androgens to estrogens. This combination therapy is used primarily for the treatment of hormone receptor-positive (HR+), HER2-negative breast cancer, including early-stage, locally advanced, and metastatic disease.