palbociclib + aromatase inhibitor

Palbociclib is an orally active, highly selective, and reversible small molecule inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6). It is used in combination with an aromatase inhibitor as initial endocrine-based therapy for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced or metastatic breast cancer. Palbociclib blocks the transition from G1 to S phase of the cell cycle by inhibiting CDK4/6-mediated phosphorylation of the retinoblastoma protein, thereby preventing cell proliferation. The combination with an aromatase inhibitor enhances anti-tumor activity by further reducing estrogen-driven signaling in HR+ breast cancer cells. This regimen was approved based on improved progression-free survival compared to aromatase inhibitor alone[1][3][5][8].

Brand names

Ibrance

Other names

palbociclib + AIpalbociclib plus aromatase inhibitor