Palbociclib in Metastatic Breast Cancer: Gene Polymorphism-based Study in Egyptian Patients.

Cyclin-dependent kinase (CDK) 4/6 inhibitors are a class of agents recently introduced in the clinic for the treatment of advanced hormone receptor-positive (HR+) and HER2-negative (HER2-) BC. Palbociclib, ribociclib and abemaciclib have all been approved by the US Food and Drug Administration (FDA) and the European Medicines Agency among other regulatory bodies