title: Lorcaserin, a novel selective human 5-hydroxytryptamine2C agonist: in vitro and in vivo pharmacological characterization.
abstract: 5-Hydroxytryptamine (5-HT)(2C) receptor agonists hold promise for the treatment of obesity. In this study, we describe the in vitro and in vivo characteristics of lorcaserin [(1R)-8-chloro-2,3,4,5-tetrahydro-1-methyl-1H-3 benzazepine], a selective, high affinity 5-HT(2C) full agonist. Lorcaserin bound to human and rat 5-HT(2C) receptors with high affinity (K(i) = 15 +/- 1 nM, 29 +/- 7 nM, respectively), and it was a full agonist for the human 5-HT(2C) receptor in a functional inositol phosphate accumulation assay, with 18- and 104-fold selectivity over 5-HT(2A) and 5-HT(2B) receptors, respectively. Lorcaserin was also highly selective for human 5-HT(2C) over other human 5-HT receptors (5-HT(1A), 5-HT(3), 5-HT(4C), 5-HT5(5A), 5-HT(6), and 5-HT(7)), in addition to a panel of 67 other G protein-coupled receptors and ion channels. Lorcaserin did not compete for binding of ligands to serotonin, dopamine, and norepinephrine transporters, and it did not alter their function in vitro. Behavioral observations indicated that unlike the 5-HT(2A) agonist (+/-)-1-(2,5-dimethoxy-4-phenyl)-2-aminopropane, lorcaserin did not induce behavioral changes indicative of functional 5-HT(2A) agonist activity. Acutely, lorcaserin reduced food intake in rats, an effect that was reversed by pretreatment with the 5-HT(2C)-selective antagonist 6-chloro-5-methyl-1-[6-(2-methylpyridin-3-yloxy)pyridin-3-yl-carbamoyl]indoline (SB242,084) but not the 5-HT(2A) antagonist (R)-(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenylethyl)]-4-piperidine-methanol (MDL 100,907), demonstrating mediation by the 5-HT(2C) receptor. Chronic daily treatment with lorcaserin to rats maintained on a high fat diet produced dose-dependent reductions in food intake and body weight gain that were maintained during the 4-week study. Upon discontinuation, body weight returned to control levels. These data demonstrate lorcaserin to be a potent, selective, and efficacious agonist of the 5-HT(2C) receptor, with potential for the treatment of obesity.
authors.affiliation: Arena Pharmaceuticals, Inc., 6166 Nancy Ridge Dr., San Diego, CA 92121, USA. bthomsen@arenapharm.com
authors.forename: William J
authors.initials: WJ
authors.lastname: Thomsen
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Grottick
authors.forename: Frederique
authors.initials: F
authors.lastname: Menzaghi
authors.forename: Hazel
authors.initials: H
authors.lastname: Reyes-Saldana
authors.forename: Stephen
authors.initials: S
authors.lastname: Espitia
authors.forename: Diane
authors.initials: D
authors.lastname: Yuskin
authors.forename: Kevin
authors.initials: K
authors.lastname: Whelan
authors.forename: Michael
authors.initials: M
authors.lastname: Martin
authors.forename: Michael
authors.initials: M
authors.lastname: Morgan
authors.forename: Weichao
authors.initials: W
authors.lastname: Chen
authors.forename: Hussien
authors.initials: H
authors.lastname: Al-Shamma
authors.forename: Brian
authors.initials: B
authors.lastname: Smith
authors.forename: Derek
authors.initials: D
authors.lastname: Chalmers
authors.forename: Dominic
authors.initials: D
authors.lastname: Behan
mesh_terms: D000631:Aminopyridines / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001552:Benzazepines / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002460:Cell Line; D004298:Dopamine / Q000378:metabolism; D004435:Eating / Q000187:drug effects*; D005464:Fluorobenzenes / Q000494:pharmacology; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D009765:Obesity / Q000188:drug therapy / Q000503:physiopathology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044405:Receptor, Serotonin, 5-HT2C / Q000502:physiology; D011994:Recombinant Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics; D012701:Serotonin / Q000378:metabolism; D058826:Serotonin 5-HT2 Receptor Agonists; D058830:Serotonin 5-HT2 Receptor Antagonists; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D014162:Transfection
chemical_list: C107820:6-chloro-5-methyl-1-((2-(2-methylpyrid-3-yloxy)pyrid-5-yl)carbamoyl)indoline; D000631:Aminopyridines; D001552:Benzazepines; D005464:Fluorobenzenes; D007211:Indoles; D010880:Piperidines; D044405:Receptor, Serotonin, 5-HT2C; D011994:Recombinant Proteins; D058826:Serotonin 5-HT2 Receptor Agonists; D058830:Serotonin 5-HT2 Receptor Antagonists; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D012701:Serotonin; C506658:lorcaserin; C079049:volinanserin; D004298:Dopamine; D009638:Norepinephrine