CDK4 and breast cancer: Additionally, ARV-471 is being explored in combination therapies with agents such as abemaciclib, ribociclib, everolimus, and Pfizer’s novel CDK-4 inhibitor (PF-07220060), expanding its potential applications for locally advanced or ER+/HER- metastatic BC (NCT06125522, NCT05573555, NCT0558127) (64).