MRT-51443

MRT-51443 is a highly selective, small molecule molecular glue degrader (MGD) targeting cyclin-dependent kinase 2 (CDK2). Developed by Monte Rosa Therapeutics, it is designed to treat HR-positive/HER2-negative breast cancer by inducing the targeted degradation of CDK2, a key driver of cell cycle progression and a common resistance mechanism to CDK4/6 inhibitors. Preclinical data suggests that MRT-51443 offers superior selectivity over traditional small molecule CDK2 inhibitors and demonstrates synergistic anti-tumor activity when combined with CDK4/6 inhibitors and endocrine therapies. The program is currently in the preclinical stage, with an Investigational New Drug (IND) application expected in 2026.