AGU654 (Compound 44) is a selective mPGES-1 inhibitor with an IC50 value of 2.9 nM against mPGES-1. By inhibiting mPGES-1, AGU654 interrupts the pathway where COX-1/2 converts arachidonic acid to prostaglandin E2 (PGE2), effectively reducing inflammatory responses, pain, and fever symptoms. In models using activated human monocyte-derived macrophages and whole blood, AGU654 selectively inhibits PGE2 production induced by bacterial endotoxins, while preserving the production of other prostaglandins. In guinea pig models, AGU654 significantly alleviates fever, inflammation, and inflammatory pain, demonstrating excellent anti-inflammatory, analgesic, and antipyretic effects. AGU654 holds promise as a new approach for researching inflammatory diseases and pain.