GW842166X is a potent and selective cannabinoid receptor 2 (CB2) agonist with IC50 values of 63 and 91 nM for human and rat CB2, respectively.
GW842166X shows similar potency and efficacy for rat and human recombinant CB2 receptors. It has no significant agonist activity at concentrations up to 30 µM in human and rat CB1 recombinant assays[1].
GW842166X has an oral ED50 of 0.1 mg/kg in the rat FCA model of inflammatory pain and shows full reversal of hyperalgesia at 0.3 mg/kg. The blood concentrations of GW842166X in experiments are 30 nM (0.03 mg/kg), 130 nM (0.1 mg/kg), and 370 nM (0.3 mg/ kg) 1 h after dosing. After dosing for 4 days in the FCA model, no statistical difference in antihyperalgesic response is observed on day 4 relative to day 1, indicating that tolerance does not occur[1].
References:
[1]. Giblin GM, et al. Discovery of 2-[(2,4-dichlorophenyl)amino]-N-[(tetrahydro- 2H-pyran-4-yl)methyl]-4-(trifluoromethyl)- 5-pyrimidinecarboxamide, a selective CB2 receptor agonist for the treatment of inflammatory pain. J Med Chem. 2007 May 31;50(11):2597-600.