The MONALEESASIA study enrolled 88 Asian patients with HR+, HER2− advanced (locoregionally recurrent or metastatic) breast cancer...ribociclib in combination with letrozole….In good responders, higher expression levels of MAP3K8 and genes regulated by E2F were observed compared with poor responders. Conversely, in poor responders higher expression levels of TYMS, FGFR1, and cell cycle‐related genes were observed compared with good responders.