1521-009X/44/9/1536–1542$25.00 http://dx.doi.org/10.1124/dmd.116.070359 DRUG METABOLISM AND DISPOSITION Drug Metab Dispos 44:1536–1542, September 2016 Copyright ª 2016 by The American Society for Pharmacology and Experimental Therapeutics Occupancy of Nociceptin/Orphanin FQ Peptide Receptors by the Antagonist LY2940094 in Rats and Healthy Human Subjects s Eyas Raddad, Amy Chappell, Jeffery Meyer, Alan Wilson, Charles E. Ruegg, Johannes Tauscher, 1 Michael A. Statnick, Vanessa Barth, Xin Zhang, and Steven J. Verfaille Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana (E.R., A.C., C.E.R., J.T., M.A.S., V.B., X.Z., S.J.V.); Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada (J.M., A.W.) Received March 7, 2016; accepted June 6, 2016 ABSTRACT Therapeutic benefits from nociceptin opioid peptide receptor (NOP) antagonism were proposed for obesity, eating disorders, and depression. LY2940094 ([2-[4-[(2-chloro-4,4-difluoro-spiro[5H- thieno[2,3-c]pyran-7,4ʹ-piperidine]-1ʹ-yl)methyl]-3-methyl-pyrazol-1-yl]- 3-pyridyl]methanol) is a novel, orally bioavailable, potent, and selective NOP antagonist. We studied NOP receptor occupancy (RO) after single oral LY2940094 doses in rat hypothalamus and human brain by use of liquid chromatography with tandem mass spectrometry (LC-MS/MS) (LSN2810397) and positron emission tomography (PET) ([ 11 C]NOP-1A) tracers, respectively. A bolus plus constant infusion tracer protocol with PET was employed in humans at 2.5 and 26.5 hours after administration of the LY2940094 dose. The RO was calculated from the change in regional distributional volume (V T ) corrected for nondisplaceable volume using Lasson plots. The RO followed a simple E max relationship to plasma LY2940094 concentration, reaching near complete occu- pancy in both species. For rat hypothalamus, the plasma concentration at half-maximum RO (EC 50 ) was 5.8 ng/ml. In humans, LY2940094 was well tolerated and safe over the 4–40 mg dose range, and it peaked in plasma at 2 to 6 hours after a 1- to 2-hour lag, with approximate dose- proportional exposure. After 4–40 mg doses, NOP RO was similar across the prefrontal cortex, occipital cortex, putamen, and thalamus, with EC 50 of 2.94 to 3.46 ng/ml, less than 2-fold lower than in rats. Over 4–40 mg doses, LY2940094 mean plasma levels at peak and 24 hours were 7.93–102 and 1.17–14.1 ng/ml, corresponding to the cross-region average NOP RO of 73%–97% and 28%–82%, respectively. The rat EC 50 translates well to humans. LY2940094 readily penetrates the human brain, and a once-daily oral dose of 40 mg achieves sustainably high (>80%) NOP RO levels suitable for testing clinical efficacy. Introduction Nociceptin/orphanin FQ (nociceptin) is a 17-amino acid neuropeptide that acts as an endogenous ligand for the opioid-like one receptor (ORL1), also known as NOP (nociceptin opioid peptide receptor). NOP is a class A G-protein–coupled receptor (Meunier et al., 1995; Reinscheid et al., 1995), is encoded by the gene opiate receptor-like 1(OPRL1), and is widely expressed in the central nervous system and specifically in regions associated with mood disorders and obesity. Symptoms of many neuropsychiatric disorders, such as pain, anxiety, depression, anorexia, obesity, and drug abuse, are believed to be poten- tially linked to the NOP receptor (Lambert, 2008; Murphy, 2010), which suggests NOP antagonism as a potential therapeutic strategy (Gavioli and Calo, 2006; Witkin et al., 2014). Interest in the target has spurred the discovery of multiple tracers. Hostetler et al. (2013) reported the discovery of [ 18 F]MK-0911, a potent, selective, and brain-penetrant positron emission tomography (PET) tracer, which was shown to have NOP binding in monkeys and humans, and was displaceable by the potent NOP antagonist MK-5757. We have recently discovered both labeled and unlabeled NOP receptor tracers with subnanomolar binding affinities with no intrinsic activity (i.e., antagonists), high selectivity, central nervous system penetration, and low nonspecific binding (Pedregal et al., 2012). LSN2810397 [Com- pound (S)-27 in Pedregal et al., 2012; NOP K i = 0.114 nM] is an unlabeled tracer based on liquid chromatography with tandem mass spectrometry (LC-MS/MS), and [ 11 C]NOP-1A (Kimura et al., 2011; Lohith et al., 2012, 2014; Pike et al., 2011) is a labeled tracer (NOP K i = 0.15 nM) that lacks brain-penetrant radiometabolites and is suitable for This work was supported by Eli Lilly and Company. E.R., S.J.V., C.E.R., M.A.S., V.B., and X.Z. are current employees of, and have financial holdings in, Eli Lilly and Company. A.C. and J.T. were employees and had financial holdings in Eli Lilly and Company during the conduct of the studies. J.M. and A.W. received operating grant funds for this study from Eli Lilly and for other studies from GlaxoSmithKline, Bristol Myers Squibb, Lundbeck, Janssen, and SK Life Sciences in the past 5 years. J.M. has consulted to these companies, with the exception of Janssen, as well as Takeda, Sepracor, Trius, Mylan, and Teva. LY2940094 and LSN2810397 were sourced from Eli Lilly and Company. 1 Current affiliation: Takeda, Deerfield, Illinois. dx.doi.org/10.1124/dmd.116.070359. s This article has supplemental material available at dmd.aspetjournals.org. ABBREVIATIONS: AE, adverse event; CAMH, Centre for Addiction and Mental Health; C p , tracer concentration in plasma; C t , average tracer concentration in the brain; EC 50 , plasma concentration at half-maximum receptor occupancy; E max , maximum occupancy; HPLC, high-performance liquid chromatography; LC-MS/MS, liquid chromatography with tandem mass spectrometry; LY2940094, [2-[4-[(2-chloro-4,4-difluoro-spiro[5H- thieno[2,3-c]pyran-7,4ʹ-piperidine]-1ʹ-yl)methyl]-3-methyl-pyrazol-1-yl]-3-pyridyl]methanol; MRI, magnetic resonance imaging; NAD-299, (3R)-3- [di(cyclobutyl)amino]-8-fluoro-3,4-dihydro-2H-chromene-5-carboxamide; NOP, nociceptin opioid peptide receptor; PET, positron emission tomography; RO, receptor occupancy; Ro-64-6198, [(1S,3aS)-2,3,3a,4,5,6-hexahydro-1H-phenalen-1-yl]-1-phenyl-1,3,8-triazaspiro[4.5]decan-4- one; ROI, regions of interest; SB-612111, (5S,7S)-7-[[4-(2,6-dichlorophenyl)piperidin-1-yl]methyl]-1-methyl-6,7,8,9-tetrahydro-5H-benzo[7]annulen- 5-ol; TEAE, treatment-emergent adverse event; V T , PET tracer distribution volume. 1536 http://dmd.aspetjournals.org/content/suppl/2016/06/27/dmd.116.070359.DC1 Supplemental material to this article can be found at: at ASPET Journals on June 14, 2020 dmd.aspetjournals.org Downloaded from