CT-173

**CT-173** is an investigational long-acting analog of peptide YY (PYY), a gut hormone that suppresses appetite, modulates gastric motility, and supports insulin secretion in response to blood glucose levels. Developed initially by Carmot Therapeutics and acquired by Roche in a $2.7 billion deal in December 2023, it showed preclinical promise in mouse models, particularly in combination with CT-388 (a GLP-1/GIP agonist), where it helped overcome weight loss plateaus and reduced post-treatment weight rebound. Roche discontinued development in July 2025, citing insufficient competitiveness and developability despite plans for Phase 1 trials.[2][4][5][6]