Imrecoxib, also known as BAP-909, a novel and selective cyclooxygenase 2 inhibitor with anti-inflammatory effect. Imrecoxib was found to inhibit COX-1 and COX-2 with IC50 value of 115+/-28 nmol/L and 18+/-4 nmol/L, respectively. Imrecoxib was shown to selectively and dose-dependently inhibit COX-2 mRNA level. Imrecoxib effectively inhibited carrageenan-induced acute inflammation at the doses of 5, 10, and 20 mg/kg i.g. and adjuvant-induced chronic inflammation at the doses of 10 and 20 mg/kg/d i.g.