Intercepting endocrine resistance in ER+/HER2− metastatic breast cancer: Insights from the PADA-1 trial

The use of cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) in combination with endocrine therapy has transformed the first-line management of oestrogen receptor-positive, HER2-negative metastatic breast cancer (ER+/HER2- mBC). Trials such as PALOMA-2 and PALOMA-3 established that adding CDK4/6 inhibitors like palbociclib to either aromatase inhibitors (AIs) or fulvestrant significantly improves progression-free and overall survival compared with endocrine therapy alone1,2.…