Arvinas and Pfizer updated clinical data from a Phase 1b combination cohort evaluating vepdegestrant in combination with palbociclib. These data show that vepdegestrant plus palbociclib continue to demonstrate encouraging clinical activity in heavily pre-treated patients with a median of four lines of prior therapy with locally advanced or metastatic ER positive/human epidermal growth factor 2 – HER2 – negative breast cancer. Vepdegestrant is an investigational PROTAC ER degrader designed to harness the body’s natural protein disposal system to specifically target and degrade the estrogen receptor.