MRT-048

**MRT-048** is a small-molecule molecular glue degrader developed by Monte Rosa Therapeutics, originating from research at The Institute of Cancer Research (ICR) and Cancer Research UK. It selectively targets GSPT1 (G1 to S phase transition 1), inducing its ubiquitination and proteasomal degradation by hijacking the Cullin 2 RING E3 ligase, thereby disrupting protein translation and selectively killing cancer cells, particularly those driven by Myc overexpression. Discovered as part of an initial library of protein degraders, it has demonstrated preclinical efficacy in Myc-driven models, including breast cancer, with potential to address undruggable targets like transcription factors.[1][3][5][9][12]