TY - JOUR T1 - A G Protein-Biased Ligand at the <em>μ</em>-Opioid Receptor Is Potently Analgesic with Reduced Gastrointestinal and Respiratory Dysfunction Compared with Morphine JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 708 LP - 717 DO - 10.1124/jpet.112.201616 VL - 344 IS - 3 AU - Scott M. DeWire AU - Dennis S. Yamashita AU - David H. Rominger AU - Guodong Liu AU - Conrad L. Cowan AU - Thomas M. Graczyk AU - Xiao-Tao Chen AU - Philip M. Pitis AU - Dimitar Gotchev AU - Catherine Yuan AU - Michael Koblish AU - Michael W. Lark AU - Jonathan D. Violin Y1 - 2013/03/01 UR - http://jpet.aspetjournals.org/content/344/3/708.abstract N2 - The concept of ligand bias at G protein-coupled receptors broadens the possibilities for agonist activities and provides the opportunity to develop safer, more selective therapeutics. Morphine pharmacology in β-arrestin-2 knockout mice suggested that a ligand that promotes coupling of the μ-opioid receptor (MOR) to G proteins, but not β-arrestins, would result in higher analgesic efficacy, less gastrointestinal dysfunction, and less respiratory suppression than morphine. Here we report the discovery of TRV130 ([(3-methoxythiophen-2-yl)methyl]({2-[(9R)-9-(pyridin-2-yl)-6-oxaspiro[4.5]decan-9-yl]ethyl})amine), a novel MOR G protein-biased ligand. In cell-based assays, TRV130 elicits robust G protein signaling, with potency and efficacy similar to morphine, but with far less β-arrestin recruitment and receptor internalization. In mice and rats, TRV130 is potently analgesic while causing less gastrointestinal dysfunction and respiratory suppression than morphine at equianalgesic doses. TRV130 successfully translates evidence that analgesic and adverse MOR signaling pathways are distinct into a biased ligand with differentiated pharmacology. These preclinical data suggest that TRV130 may be a safer and more tolerable therapeutic for treating severe pain. ER -