SHR9549

SHR9549 is an orally available, small molecule selective estrogen receptor degrader (SERD) developed by Jiangsu Hengrui Medicine (also referred to as Shanghai Hengrui Pharmaceutical). It specifically targets and binds to the estrogen receptor (ER), inducing a conformational change that promotes ER degradation and downregulation. This mechanism inhibits estrogen signaling in cancer cells, suppressing tumor growth. SHR9549 was investigated primarily for the treatment of ER-positive, HER2-negative advanced or metastatic breast cancer. The drug demonstrated potent ER degradation activity in preclinical studies but its clinical development was discontinued after a phase I trial due to dose-limiting toxicity observed in one patient[1][2][3][5].