title: APD791, 3-methoxy-n-(3-(1-methyl-1h-pyrazol-5-yl)-4-(2-morpholinoethoxy)phenyl)benzamide, a novel 5-hydroxytryptamine 2A receptor antagonist: pharmacological profile, pharmacokinetics, platelet activity and vascular biology.
abstract: We have evaluated the receptor pharmacology, antiplatelet activity, and vascular pharmacology of APD791 [3-methoxy-N-(3-(1-methyl-1H-pyrazol-5-yl)-4-(2-morpholinoethoxy)phenyl)benzamide] a novel 5-hydroxytryptamine 2A (5-HT(2A)) receptor antagonist. APD791 displayed high-affinity binding to membranes (K(i) = 4.9 nM) and functional inverse agonism of inositol phosphate accumulation (IC(50) = 5.2 nM) in human embryonic kidney cells stably expressing the human 5-HT(2A) receptor. In competition binding assays, APD791 was greater than 2000-fold selective for the 5-HT(2A) receptor versus 5-HT(2C) and 5-HT(2B) receptors, and was inactive when tested against a wide panel of other G-protein-coupled receptors. APD791 inhibited 5-HT-mediated amplification of ADP-stimulated human and dog platelet aggregation (IC(50) = 8.7 and 23.1 nM, respectively). Similar potency was observed for inhibition of 5-HT-stimulated DNA synthesis in rabbit aortic smooth muscle cells (IC(50) = 13 nM) and 5-HT-mediated vasoconstriction in rabbit aortic rings. Oral administration of APD791 to dogs resulted in acute (1-h) and subchronic (10-day) inhibition of 5-HT-mediated amplification of collagen-stimulated platelet aggregation in whole blood. Two active metabolites, APD791-M1 and APD791-M2, were generated upon incubation of APD791 with human liver microsomes and were also indentified in dogs after oral administration of APD791. The affinity and selectivity profiles of both metabolites were similar to APD791. These results demonstrate that APD791 is an orally available, high-affinity 5-HT(2A) receptor antagonist with potent activity on platelets and vascular smooth muscle.
authors.affiliation: Arena Pharmaceuticals, Inc., San Diego, CA 92121, USA. jadams@arenapharm.com
authors.forename: John W
authors.initials: JW
authors.lastname: Adams
authors.forename: Juan
authors.initials: J
authors.lastname: Ramirez
authors.forename: Yunqing
authors.initials: Y
authors.lastname: Shi
authors.forename: William
authors.initials: W
authors.lastname: Thomsen
authors.forename: John
authors.initials: J
authors.lastname: Frazer
authors.forename: Michael
authors.initials: M
authors.lastname: Morgan
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Edwards
authors.forename: Weichao
authors.initials: W
authors.lastname: Chen
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Teegarden
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Xiong
authors.forename: Hussien
authors.initials: H
authors.lastname: Al-Shamma
authors.forename: Dominic P
authors.initials: DP
authors.lastname: Behan
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Connolly
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D001549:Benzamides / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects* / Q000502:physiology; D002460:Cell Line; D018592:Cross-Over Studies; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D000882:Haplorhini; D006801:Humans; D008297:Male; D009025:Morpholines / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D015539:Platelet Activation / Q000187:drug effects / Q000502:physiology*; D011720:Pyrazoles / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology*; D011817:Rabbits; D051381:Rats; D044402:Receptor, Serotonin, 5-HT2A / Q000097:blood / Q000502:physiology*; D058830:Serotonin 5-HT2 Receptor Antagonists; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D013045:Species Specificity
chemical_list: C544126:APD791; D001549:Benzamides; D009025:Morpholines; D011720:Pyrazoles; D044402:Receptor, Serotonin, 5-HT2A; D058830:Serotonin 5-HT2 Receptor Antagonists; D012702:Serotonin Antagonists