exemestane + leuprolide + palbociclib

Exemestane + leuprolide + palbociclib is a three-drug combination regimen used primarily in the treatment of hormone receptor-positive, HER2-negative metastatic breast cancer in premenopausal women. Exemestane is a steroidal aromatase inhibitor that suppresses estrogen synthesis by irreversibly binding to the aromatase enzyme, thereby reducing estrogen levels and limiting tumor growth driven by estrogen signaling. Leuprolide is a gonadotropin-releasing hormone (GnRH) agonist that induces ovarian suppression, further lowering circulating estrogen levels in premenopausal patients. Palbociclib is an oral small molecule inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6), which blocks cell cycle progression from G1 to S phase, inhibiting proliferation of cancer cells dependent on this pathway. The combination has demonstrated improved progression-free survival compared to chemotherapy with capecitabine in clinical trials for premenopausal women with HR-positive/HER2-negative metastatic breast cancer[1][2][4][6].