Brexpiprazole I: in vitro and in vivo characterization of a novel serotonin-dopamine activity modulator.

Article Details

Citation

Maeda K, Sugino H, Akazawa H, Amada N, Shimada J, Futamura T, Yamashita H, Ito N, McQuade RD, Mork A, Pehrson AL, Hentzer M, Nielsen V, Bundgaard C, Arnt J, Stensbol TB, Kikuchi T

Brexpiprazole I: in vitro and in vivo characterization of a novel serotonin-dopamine activity modulator.

J Pharmacol Exp Ther. 2014 Sep;350(3):589-604. doi: 10.1124/jpet.114.213793. Epub 2014 Jun 19.

PubMed ID
24947465 [ View in PubMed
]
Abstract

Brexpiprazole (OPC-34712, 7-{4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one) is a novel drug candidate in clinical development for psychiatric disorders with high affinity for serotonin, dopamine, and noradrenaline receptors. In particular, it bound with high affinity (Ki < 1 nM) to human serotonin 1A (h5-HT1A)-, h5-HT2A-, long form of human D2 (hD2L)-, halpha1B-, and halpha2C-adrenergic receptors. It displayed partial agonism at h5-HT1A and hD2 receptors in cloned receptor systems and potent antagonism of h5-HT2A receptors and halpha1B/2C-adrenoceptors. Brexpiprazole also had affinity (Ki < 5 nM) for hD3-, h5-HT2B-, h5-HT7-, halpha1A-, and halpha1D-adrenergic receptors, moderate affinity for hH1 (Ki = 19 nM), and low affinity for hM1 receptors (Ki > 1000 nM). Brexpiprazole potently bound to rat 5-HT2A and D2 receptors in vivo, and ex vivo binding studies further confirmed high 5-HT1A receptor binding potency. Brexpiprazole inhibited DOI (2,5-dimethoxy-4-iodoamphetamine)-induced head twitches in rats, suggestive of 5-HT2A antagonism. Furthermore, in vivo D2 partial agonist activity of brexpiprazole was confirmed by its inhibitory effect on reserpine-induced DOPA accumulation in rats. In rat microdialysis studies, brexpiprazole slightly reduced extracellular dopamine in nucleus accumbens but not in prefrontal cortex, whereas moderate increases of the dopamine metabolites, homovanillic acid and DOPAC (3,4-dihydroxy-phenyl-acetic acid), in these areas also suggested in vivo D2 partial agonist activity. In particular, based on a lower intrinsic activity at D2 receptors and higher binding affinities for 5-HT1A/2A receptors than aripiprazole, brexpiprazole would have a favorable antipsychotic potential without D2 receptor agonist- and antagonist-related adverse effects. In conclusion, brexpiprazole is a serotonin-dopamine activity modulator with a unique pharmacology, which may offer novel treatment options across a broad spectrum of central nervous system disorders.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
Brexpiprazole5-hydroxytryptamine receptor 1AProteinHumans
Unknown
Partial agonist
Details
Brexpiprazole5-hydroxytryptamine receptor 2AProteinHumans
Unknown
Antagonist
Details
BrexpiprazoleDopamine D2 receptorProteinHumans
Unknown
Partial agonist
Details