SYH2043

SYH2043 is an innovative oral small molecule inhibitor that selectively targets cyclin-dependent kinases 2, 4, and 6 (CDK2/4/6). By inhibiting these kinases, SYH2043 blocks the phosphorylation of retinoblastoma protein (Rb) early in the G1 phase of the cell cycle, thereby preventing CDK-mediated transition from G1 to S phase. This mechanism disrupts cell proliferation and has demonstrated antitumor effects in preclinical studies across multiple solid tumor types. Notably, it shows efficacy in breast cancers with intrinsic or acquired resistance to existing CDK4/6 inhibitors. The drug is being developed by CSPC Pharmaceutical Group (also known as CSPC Ouyi Pharmaceutical), with clinical trials underway to evaluate its safety, tolerability, pharmacokinetics/pharmacodynamics, and preliminary antitumor activity in patients with advanced malignant tumors[1][2][5][7].