In the front-line treatment of human epidermal growth factor receptor 2-positive patients, dalpiciclib with pyrotinib demonstrates promising efficacy and acceptable tolerability. A highly selective, small-molecule CDK4/6 inhibitor, palbociclib (SHR6390), was recently authorized in China for hormone receptor (HR)-positive, human epidermal growth factor receptor (HER)2-negative advanced breast cancer (ABC). Pyrotinib is an orally administered, irreversible pan-ErbB...