Microsomal Prostaglandin E2 Synthase-1 (mPGES-1), with cyclooxygenase-2 (COX-2), synthesizes PGE2, which is directly involved in signaling during inflammation, fever and pain. 5-Lipoxygenase (5-LO) initiates the synthesis of leukotrienes (LTs), which are pro-inflammatory mediators. CAY10589 is a dual inhibitor of mPGES-1 (IC50 = 1.3 μM) and 5-LO (IC50 = 1.0 μM). It effectively inhibits PGE2 and LT synthesis in both cell free and intact cell assays. CAY10589 has minor effects on COX-1 and COX-2, inhibiting these enzymes 34% and 38.8%, respectively, at 10 μM.