Background:

Etoricoxib (MK-0663) is a non steroidal anti-inflammatory agent, acting as a selective and orally active COX-2 inhibitor, with IC50s of 1.1 μM and 116 μM for COX-2 and COX-1 in human whole blood.

Etoricoxib (MK-0663) is a selective and orally active COX-2 inhibitor, with IC50s of 1.1 μM, 116 μM and 5 μM for COX-2, COX-1 in human whole blood and purified human COX-2, respectively. Etoricoxib (MK-0663) shows inhibitory effect on PGE2 production by CHO (COX-2) cells (IC50, 79 nM), on purified human COX-2 with detergent (IC50, 4.1 μM), and on purified PGE2 production by U937 microsomes (low substrate; IC50, 12.1 μM). However, Etoricoxib (MK-0663) has little activity against COX-1 with a Ki of 167 μM[1].

Etoricoxib (MK-0663) (0.1-30 mg/kg, p.o.) dose-dependently inhibits carrageenan-induced paw edema, carrageenan-induced paw hyperalgesia, and endotoxin-induced pyresis in rats. Etoricoxib (≥10 mg/kg) completely reverses hyperalgesia response in the rat hyperalgesia model. Etoricoxib (MK-0663) (200 mg/kg/day) has no effect on urinary 51Cr excretion in rats, and nor in monkeys at 100 mg/kg/day[1]. Etoricoxib (MK-0663) (50 and 100?mg/kg) potently increases the malondialdehyde (MDA) and myeloperoxidase (MPO) levels, and decreases the total glutathione (tGSH) and glutathione reductase (GSHRd) levels in rats. Etoricoxib (MK-0663) (100?mg/kg) significantly inhibits the decrease of NO in rats[2]. Etoricoxib (MK-0663) (0.64 mg/kg, p.o.) reduces the features such as multiple plaque lesions, hyperplasia and dysplasia induced by 1,2-dimethylhydrazine dihydrochloride (DMH) in rats[3].

Reference:
[1]. Riendeau D, et al.Etoricoxib (MK-0663): preclinical profile and comparison with other agents that selectively inhibit cyclooxygenase-2. J Pharmacol Exp Ther. 2001 Feb;296(2):558-66.
[2]. Kunak CS, et al. The Effect of Etoricoxib on Hepatic Ischemia-Reperfusion Injury in Rats. Oxid Med Cell Longev. 2015;2015:598162.
[3]. Tanwar L, et al. Anti-proliferative and apoptotic effects of etoricoxib, a selective COX-2 inhibitor, on 1,2-dimethylhydrazine dihydrochloride-induced colon carcinogenesis. Asian Pac J Cancer Prev. 2010;11(5):1329-33.