GLP-1–pathway agonists such as semaglutide and newer multi-agonists have transformed care for obesity and diabetes, yet developers still wrestle with durability, tissue targeting, and signal “bias.” Macrocyclization, tying part of a peptide into a ring, can shield drugs from degradation and favor bioactive shapes, but conventional chemistry can be costly and hard to apply late in development.
A research team at Sethera Therapeutics and the Bandarian Lab at the University of Utah has shown that a radical enzyme can “tie off” therapeutic peptides into compact rings without the usual leader-sequence requirements.