A CB2 receptor agonist and inverse agonist; greater than 100-fold selective for the CB2 (Ki = 15 nM) over the CB1 receptor (Ki = 5,000 nM); acts as an agonist at human CB2 receptors (EC50 = 118 nM) but an inverse agonist of rat and mouse CB2 receptors (EC50s = 315 and 341 nM, respectively); produces antinociception to thermal, but not mechanical, pain in rats