SB-612111 is a novel and potent human opiate receptor-like orphan receptor (ORL-1) antagonist with a high affinity for hORL-1 (Ki=0.33 nM). SB-612111 exhibits selectivity for μ-, κ- and δ-receptors with Ki values of 57.6 nM, 160.5 nM and 2109 nM, respecticely. SB-612111 effectively antagonizes the pronociceptive action of Nociceptin in an acute pain model[1].