Brexpiprazole (OPC-34712) is a partial agonist of human 5-hydroxytryptamine (5-HT) 5-HT1A and dopamine D2 receptors.

D2L:0.3 nM(Ki), 5-HT1A:0.12 nM(Ki), Noradrenaline α1B (human):0.17 nM(Ki), 5-HT2A receptor:0.47 nM(Ki), α2C-adrenoceptor:0.59 nM(Ki)

Brexpiprazole is a potent partial agonist at human 5-hydroxytryptamine (5-HT) 5-HT1A (Ki=0.12 nM) and dopamine D2L (Ki=0.3 nM) receptors, and an antagonist at 5-HT2A receptors (Ki=0.47 nM). It also shows potent antagonist activity at human noradrenergic α1B (Ki=0.17 nM) and α2Creceptors (Ki=0.59 nM). Furthermore, this drug displays moderate affinity for human D3, 5-HT2B and 5-HT7 receptors, as well as α1A, and α1D adrenergic receptors. Brexpiprazole potentiated NGF-induced neurite outgrowth in PC12 cells. It could significantly potentiate the effects of fluoxetine (or paroxetine) on neurite outgrowth[1].

Brexpiprazole is able to ameliorate PCP- 191 induced cognitive deficits in mice, via 5-HT1A receptors[2].

2.5 ng/ml of NGF(nerve growth factor) is used to study the potentiating effects of brexpiprazole on neurite outgrowth. Twenty-four hours after plating, the medium is replaced with DMEM medium containing 0.5% FBS and 1% penicillin-streptomycin with NGF (2.5 ng/ml), with or without brexpiprazole (0.001, 0.01, 0.1 or 1.0 μM). Four days after incubation with NGF (2.5 ng/ml) with or without drugs, morphometric analysis is performed on digitized images of live cells taken under phase-contrast illumination, with an inverted microscope linked to a camera. (Only for Reference)