5-HT1A Receptor (Ki = 0.12 nM); 5-HT2A Receptor (Ki = 0.47 nM); D2L Receptor (Ki = 0.3 nM); human noradrenergic α1B (Ki = 0.17 nM); human noradrenergic α2C (Ki = 0.59 nM)

In PC12 cells, breexpipromaze (0-1.0 μM, 4 days) dose-dependently promotes NGF-induced neurite outgrowth [1].

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Brexpiprazole, a novel atypical antipsychotic drug, is currently being tested in clinical trials for treatment of psychiatric disorders, such as schizophrenia and major depressive disorder. The drug is known to act through a combination of partial agonistic activity at 5-hydroxytryptamine (5-HT)1A, and dopamine D2 receptors, and antagonistic activity at 5-HT2A receptors. Accumulating evidence suggests that antipsychotic drugs act by promoting neurite outgrowth. In this study, we examined whether brexpiprazole affected neurite outgrowth in cell culture. We found that brexpiprazole significantly potentiated nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells, in a concentration dependent manner. The selective 5-HT1A receptor antagonist, WAY-100,635, was able to block the effects of brexpiprazole on neurite outgrowth, unlike the selective dopamine D2 receptor antagonist, raclopride. Furthermore, the selective 5-HT2A receptor antagonist M100907, but not DOI (5-HT2A receptor agonist), significantly potentiated NGF-induced neurite outgrowth. Moreover, xestospongin C and 2-aminoethoxydiphenyl borate (2-APB), both specific inhibitors of inositol 1,4,5-triphosphate (IP3) receptors, significantly blocked the effects of brexpiprazole. These findings suggest that brexpiprazole-induced neurite outgrowth is mediated through 5-HT1A and 5-HT2A receptors, and subsequent Ca(2+) signaling via IP3 receptors[1].

Brexpiprazole (0-0.1 mg/kg; oral; once) improves social cognition impairments in mice [2].
Brexpiprazole (7-{4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one), a novel serotonin-dopamine activity modulator, was developed to offer efficacious and tolerable therapy for different psychiatric disorders, including schizophrenia and adjunctive treatment of MDD. In this study, we investigated whether brexpiprazole could improve social recognition deficits (one of social cognition deficits) in mice, after administration of the N-methyl-d-aspartate (NMDA) receptor antagonist MK-801 (dizocilpine). Dosing with dizocilpine (0.1mg/kg) induced significant impairment of social recognition in mice. Brexpiprazole (0.01, 0.03, 0.1mg/kg, p.o.) significantly ameliorated dizocilpine-induced social recognition deficits, without sedation or a reduction of exploratory behavior. In addition, brexpiprazole alone had no effect on social recognition in untreated control mice. By contrast, neither risperidone (0.03mg/kg, p.o.) nor olanzapine (0.03mg/kg, p.o.) altered dizocilpine-induced social recognition deficits. Finally, the effect of brexpiprazole on dizocilpine-induced social recognition deficits was antagonized by WAY-100,635, a selective serotonin 5-HT1A antagonist. These results suggest that brexpiprazole could improve dizocilpine-induced social recognition deficits via 5-HT1A receptor activation in mice. Therefore, brexpiprazole may confer a beneficial effect on social cognition deficits in patients with psychiatric disorders[2].

Cell culture and quantification of neurite outgrowth [1]
PC12 cells were cultured at 37 °C, 5% CO2 in Dulbecco׳s modified Eagle׳s medium (DMEM), supplemented with 5% heat-inactivated fetal bovine serum (FBS), 10% heat-inactivated horse serum, and 1% penicillin–streptomycin. Medium was changed two to three times a week. PC12 cells were plated onto 24-well tissue culture plates coated with poly-d-lysine/laminin. Cells were plated at relatively low density (0.25×104 cells/cm2) in DMEM medium containing 0.5% FBS, 1% penicillin–streptomycin. Medium containing a minimal level of serum (0.5% FBS) was used as previously reported (Nishimura et al., 2008, Ishima et al., 2008, Ishima et al., 2012, Minase et al., 2010, Hashimoto and Ishima, 2010, Hashimoto and Ishima, 2011, Itoh et al., 2011, Ishima and Hashimoto, 2012). Previously, we examined the optimal concentration of NGF needed to induce neurite outgrowth in PC12 cells, and found that NGF (2.5, 5, 10, 20, 40 ng/ml) increased the number of cells with neurite outgrowth in a concentration-dependent manner (Nishimura et al., 2008). In this study, 2.5 ng/ml of NGF was used to study the potentiating effects of brexpiprazole on neurite outgrowth. Twenty-four hours after plating, the medium was 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), WAY-100,635 (5-HT1A receptor antagonist; 10 μM), raclopride (dopamine D2 receptor antagonist; 10 μM), DOI (5-HT2A receptor agonist; 0.1, 1.0 or 10 μM), M100,907 (5-HT2A receptor antagonist; 0.1, 1.0 or 10 μM), xestospongin C (IP3 receptor antagonist; 1.0 μM), 2-APB (IP3 receptor antagonist; 100 μM), fluoxetine (5-HT transporter inhibitor: 1.0 μM), or paroxetine (5-HT transporter inhibitor: 1.0 μM). Four days after incubation with NGF (2.5 ng/ml) with or without specified drugs, morphometric analysis was performed on digitized images of live cells taken under phase-contrast illumination, with an inverted microscope linked to a camera. Images of three fields per well were taken, with an average of 100 cells per field. Differentiated cells were counted by visual examination of the field; only cells that had at least one neurite with a length equal to the cell body diameter were counted, and were then expressed as a percentage of the total cells in the field. Counting was performed in a blinded manner.

Animal/Disease Models: Male C57BL/6NCrSlc mice, dizozepine (0.1 mg/kg)-induced social recognition deficit [2]
Doses: 0.01, 0.03 and 0.1 mg/kg
Route of Administration: Oral administration, once
Experimental Results:Significant Amelioration of dizozepine-induced social recognition deficits without sedation or reduction in exploratory behavior.

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Brexpiprazole, risperidone, olanzapine and WAY-100,635 were dissolved in 5% (w/v) gum Arabic and administered orally (p.o.), at 10 ml/kg, 1 h prior to sociability testing. Male C57BL/6NCrSlc mice aged between 4 and 5 weeks old were selected as stranger mice, while animals between 8 and 10 weeks old were used for this study.

Absorption, Distribution and Excretion
Following a single dose, the time to peak concentration (Tmax) is 4 hours, and the absolute oral bioavailability is 95%. Steady-state concentrations of birepiperazole are reached within 10 to 12 days after administration. Both Cmax and AUC increase proportionally with single and multiple once-daily doses. A high-fat diet has no significant effect on the Cmax or AUC of birepiperazole. Following a single oral dose of radiolabeled birepiperazole, approximately 25% and 46% of the radioactive material are recovered in urine and feces, respectively. Less than 1% of the unchanged birepiperazole is excreted in urine, and approximately 14% of the oral dose is excreted unchanged in feces. The volume of distribution after intravenous administration of birepiperazole is 1.56 ± 0.42 L/kg, indicating extravascular distribution.
After once-daily administration, the apparent oral clearance of biriperazole is 19.8 (±11.4) mL/h/kg.
Metabolism/Metabolites
In vitro studies have shown that biriperazole is primarily metabolized by CYP3A4 and CYP2D6. After single and multiple administrations, biriperazole and its major metabolite DM-3411 are the major circulating components. At steady state, DM-3411 accounts for 23% to 48% of the plasma biriperazole exposure (AUC). DM-3411 is considered to be pharmacologically inactive.
Biological Half-Life
After once-daily or multiple administrations, the terminal elimination half-lives of biriperazole and its major metabolite DM-3411 are 91 hours and 86 hours, respectively.

Hepatotoxicity
It has been reported that approximately 1% of patients taking bripiprazole long-term develop abnormal liver function, but the incidence is similar in the placebo or control groups. There are currently no reports of clinically significant acute liver injury caused by bripiprazole, and only a very small number of cases have been reported with the more commonly used aripiprazole. Therefore, liver injury caused by bripiprazole, even if it occurs, is certainly very rare. Probability score: E (unlikely to cause clinically significant liver injury). Pregnancy and Lactation Effects ◉ Overview of Use During Lactation There is currently no information on whether bripiprazole is excreted into breast milk. One case report indicates that bripiprazole may cause reduced lactation. A case report review found reports of bripiprazole causing lactation disorders and reduced milk production, but details are lacking. Until more data are available, alternative medications may be preferred. ◉ Effects on Breastfed Infants As of the revision date, no relevant published information was found.
◉ Effects on Lactation and Breast Milk
A woman with bipolar disorder was taking irinotecan 2 mg/day during late pregnancy. Her newborn was hospitalized in the neonatal intensive care unit (NICU) for 18 days with hypoxic-ischemic encephalopathy. During the baby's hospitalization, due to medication shortages, she reduced the irinotecan dose to 2 mg every two days. This mother had previously successfully breastfed two babies, pumping 10 times a day, producing 120 ml per day in the first week postpartum. After the baby was discharged, she restored the dose to 2 mg daily. At a follow-up outpatient visit, she could only express 30 ml per day. She then discontinued irinotecan and began a short course of metoclopramide. Ten days after discontinuing irinotecan, her milk production increased, allowing her to almost exclusively breastfeed her baby, whose weight gain was normal. Her serum prolactin levels also returned to normal. A review of adverse reaction cases reported in the U.S. Food and Drug Administration's Adverse Event Reporting System between 2015 and 2023 revealed 6 cases of "galactorrhea" and 10 cases of "nipple discharge" related to biriperazole. Other details were missing. Protein Binding: In vitro experiments showed that biriperazole binds to 99% of plasma proteins, primarily serum albumin and α1-acid glycoprotein.

[1]. Potentiation of neurite outgrowth by brexpiprazole, a novel serotonin-dopamine activity modulator: a role for serotonin 5-HT1A and 5-HT2A receptors. Eur Neuropsychopharmacol. 2015 Apr;25(4):505-11.

[2]. Improvement of dizocilpine-induced social recognition deficits in mice by brexpiprazole, a novel serotonin-dopamine activity modulator. Eur Neuropsychopharmacol. 2015 Mar;25(3):356-64.

Brepiprazole is an N-arylpiperazine compound. It is an atypical antipsychotic and a novel partial agonist of D2 dopamine and serotonin 1A receptors, known as a serotonin-dopamine activity modulator (SDAM). It has high affinity for serotonin, dopamine, and alpha-adrenergic receptors. Although structurally similar to aripiprazole, brepiprazole has different binding affinities for dopamine and serotonin receptors. Compared to aripiprazole, brepiprazole is less likely to cause partially agonist-mediated adverse reactions (such as extrapyramidal symptoms) due to its lower intrinsic activity against D2 receptors. Furthermore, it exhibits stronger antagonistic activity against 5-HT1A and 5-HT2A receptors. Brexpiprazole was first approved by the FDA on July 10, 2015. Currently, Brexpiprazole is approved for the treatment of depression, schizophrenia, and dementia-related agitation in Alzheimer's disease. It is also being investigated for the treatment of other mental illnesses, such as post-traumatic stress disorder. Brexpiprazole is an atypical antipsychotic. Brexpiprazole is an atypical antipsychotic used to treat schizophrenia and major depressive disorder. The incidence of elevated serum transaminases during Brexpiprazole treatment is low, but it has not been found to be associated with clinically significant cases of acute liver injury.

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Drug Indications
Brexpiprazole is indicated as adjunctive therapy to antidepressants for the treatment of major depressive disorder in adults. It is also indicated for the treatment of schizophrenia in patients aged 13 years and older. Brexpiprazole is also indicated for the treatment of dementia-related agitation in Alzheimer's disease; however, it is not indicated for on-demand (“prn”) treatment of this condition. Treatment of Schizophrenia.
Treatment of Schizophrenia

Mechanism of Action

Although the exact mechanism of action of iriperazole in mental disorders is not fully elucidated, its efficacy may be attributed to its partial agonistic activity against 5-HT1A and dopamine D2 receptors, as well as its antagonistic activity against 5-HT2A receptors. Iriperazole has sub-nanomolar affinity for these receptors. These therapeutic targets are associated with mental disorders such as schizophrenia and depression. The partial D2 receptor agonist effect allows the drug to stimulate D2 receptors at low dopamine levels and attenuate their activation at high dopamine levels. Partial agonistic activity against 5-HT1A receptors may be associated with improvements in memory function and cognitive abilities. Antagonistic activity against α-adrenergic receptors is also associated with schizophrenia and depression. In summary, iriperazole improved social recognition deficits in mice after dezoceppine administration, while the 5-HT1A receptor antagonist WAY-100,635 reversed the effect of iriperazole in this model. Our findings suggest that iriperazole may be a potential treatment for social cognitive impairment in patients with schizophrenia and major depressive disorder. [2]

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In summary, our findings indicate that iriperazole enhances NGF-induced neurite growth in PC12 cells by activating 5-HT1A and 5-HT2A receptors and subsequently via IP3 receptor-mediated Ca2+ signaling. Furthermore, iriperazole-induced elevation of Hsp90α protein levels also apparently plays a role in NGF-induced neurite growth. [1]

C25H28CLN3O2S

470.026723861694

469.159

913612-38-1

Brexpiprazole;913611-97-9

66884211

Typically exists as solid at room temperature

2

5

7

32

636

0

RQCIZERYSLEVFB-UHFFFAOYSA-N

InChI=1S/C25H27N3O2S.ClH/c29-25-9-7-19-6-8-20(18-22(19)26-25)30-16-2-1-11-27-12-14-28(15-13-27)23-4-3-5-24-21(23)10-17-31-24;/h3-10,17-18H,1-2,11-16H2,(H,26,29);1H

7-[4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy]-1H-quinolin-2-one;hydrochloride

Brexpiprazole dihydrochloride; Brexpiprazole hydrochloride; 913612-38-1; 7-(4-(4-(Benzo[b]thiophen-4-yl)piperazin-1-yl)butoxy)quinolin-2(1H)-one hydrochloride; 1420987-74-1; SCHEMBL1034589; RQCIZERYSLEVFB-UHFFFAOYSA-N;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)