CP 945598

CP 945598 (Otenabant) is a potent and selective cannabinoid type 1 receptor antagonist that inhibits both basal and cannabinoid agonist-mediated CB(1) receptor signaling in vitro and in vivo. CP-945598 exhibits sub-nanomolar potency at human CB1 receptors in both binding (Ki = 0.7 nM) and functional assays (Ki = 0.2 nM) in vitro. CP-945598 (Otenabant) also acutely stimulates energy expenditure in rats and decreases the respiratory quotient indicating a metabolic switch to increased fat oxidation. A phase 1 study with CP-945598 of the roles of endocannabinoids in insulin secretion and action is recruiting.