– Data Highlight Essential Role of GSPT1 in Sustaining Myc-induced Translational Addiction in Solid Tumors –

BOSTON, MA, USA I April 08, 2022 I Monte Rosa Therapeutics, Inc. (NASDAQ: GLUE), a biotechnology company developing novel molecular glue degrader (MGD)-based medicines, today announced preclinical data underscoring the role of GSPT1 as a key regulator of protein translation in Myc-driven tumors and highlighting MRT-2359 as a potent and selective GSPT1-directed MGD. The data will be presented in a poster presentation titled, “Identification of MRT-2359, a Potent, Selective and Orally Bioavailable GSPT1-directed Molecular Glue Degrader (MGD) for the Treatment of Cancers with Myc-induced Translational Addiction,” at the American Association for Cancer Research (AACR) Annual Meeting in New Orleans.

“Myc transcription factors are well-established drivers of human cancers, and our analyses of real-world molecular and genomic data of more than 3,000 lung cancer samples continue to underscore their role as some of the most frequently mutated, translocated and overexpressed oncogenes,” said Owen Wallace, Ph.D., Chief Scientific Officer of Monte Rosa. “To sustain uncontrolled cell proliferation and tumor growth, Myc-driven tumors hijack critical components of the translational machinery – including the translational termination factor GSPT1 – providing, in turn, a unique opportunity for therapeutic intervention. Our presentation at AACR represents the culmination of extensive and compelling preclinical in vivo data demonstrating the therapeutic potential of MRT-2359 as a potent, highly selective degrader of GSPT1. We look forward to submitting our IND for MRT-2359 in mid-2022.”

Summary of Findings
The data being presented at the AACR meeting are based on preclinical studies and analyses of real-world data derived from patient tumor samples. Findings include the following:

  • MRT-2359 induces degradation of GSPT1 and associated downregulation of N-Myc and its transcriptional output, leading to preferential anti-proliferative activity in lung cancer cell lines with high L-Myc and N-Myc mRNA expression.
  • MRT-2359, when administered orally, demonstrates anti-tumor activity in xenograft and patient-derived xenograft (PDX) models of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) with high L-Myc and/or N-Myc mRNA expression levels or neuroendocrine features.
  • MRT-2359 had limited activity in low L-Myc or N-Myc NSCLC models, further corroborating the selective vulnerability of Myc-driven tumors to GSPT1 degradation.
  • Analyses of real-world data indicate that approximately 15% of NSCLC and 70% of SCLC have high L-Myc and/or N-Myc mRNA expression.
  • Collectively, these data support the clinical development of MRT-2359 in Myc-driven solid tumors, with an initial focus on NSCLC and SCLC.

About Monte Rosa
Monte Rosa Therapeutics is a biotechnology company developing a portfolio of novel molecular glue degrader medicines. These medicines are designed to employ the body’s natural mechanisms to selectively eliminate therapeutically relevant proteins. The company has developed a proprietary protein degradation platform, called QuEEN™ (Quantitative and Engineered Elimination of Neosubstrates), that enables it to rapidly identify protein targets and molecular glue degrader, or MGD, product candidates that are designed to eliminate therapeutically relevant proteins in a highly selective manner. The company’s drug discovery platform combines diverse and proprietary chemical libraries of small molecule protein degraders with in-house proteomics, structural biology, AI/machine learning-based target selection and computational chemistry capabilities to predict and obtain protein degradation profiles. For more information, visit www.monterosatx.com

SOURCE: Monte Rosa Therapeutics