HS-10342

HS-10342 is an orally available, small molecule drug that acts as a selective inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6). By inhibiting CDK4 and CDK6, it prevents the phosphorylation of retinoblastoma protein (Rb) during the early G1 phase of the cell cycle, thereby blocking the transition from G1 to S phase and inducing cell cycle arrest. This mechanism targets uncontrolled cellular proliferation in cancer. The drug has been primarily developed for oncology indications, including advanced solid tumors and hormone receptor-positive/HER2-negative breast cancer. It was originally developed by Shanghai Hansoh Biomedical Co. Ltd., with clinical development led by Jiangsu Hansoh Pharmaceutical[1][2][3][4][6].