Ileal bile acid transporter/IBAT (IC50 = 0.53 nM); IL-6; TNF-α/β

Elobixibat reduces BA reabsorption in the terminal ileum, resulting in increased BA excretion in stool and higher BA concentration in the colon, which enhances the secretion of water and electrolytes into the colon, improves intestinal motility, and eases colonic transit.[2]

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Elobixibat (formerly A3309) is a first-in-class ileal bile acid transporter (IBAT) inhibitor for treatment of chronic idiopathic constipation (CIC; syn functional constipation). CIC affects up to 25% of the general population; and up to a half are unsatisfied with current therapies. There is an unmet need for safe and effective drugs to treat CIC.Elobixibat provides a novel approach to treat chronic constipation via IBAT inhibition with enhanced delivery of bile acids to the colon. [1]

Treatment with elobixibat reduced the serum BA and increased the fecal BA concentration, and ameliorated the liver inflammation and fibrosis. It also reduced the expression of proinflammatory cytokines in the liver and MLNs, and transforming growth factor-β expression in the liver. Finally, elobixibat normalized intestinal tight junction protein level and the composition of the intestinal microbiota. Conclusion: elobixibat ameliorates NASH-related histopathology, reduces cytokine expression, and normalizes the intestinal microbial composition in MCD-fed mice, which suggests that it may represent a promising candidate for the therapy of NASH.[3]

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Both groups showed liver fat accumulation and fibrosis, with no significant differences between the two groups. However, mice with elobixibat showed fewer liver tumors. The total serum bile acid levels, including free, tauro-conjugated, glyco-conjugated, and tauro-α/β-muricholic acids in the liver, were noticeably reduced following elobixibattreatment. The proportion of gram-positive bacteria in feces was significantly lower in the group treated with elobixibat (5.4%) than in the group without elobixibat (33.7%). Conclusion: elobixibat suppressed tumor growth by inhibiting bile acid reabsorption, and decreasing total bile acid and primary bile acid levels in the serum and liver. Additionally, the presence of bile acids in the colon may have led to a significant reduction in the proportion of gram-positive bacteria, potentially resulting in decreased secondary bile acid synthesis.[2]

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Pharmacodynamic studies show that it accelerates colonic transit, increases stool frequency, loosens stool consistency and relieves constipation-related symptoms in CIC patients. These beneficial effects are maintained for a minimum of 8 consecutive weeks of treatment. With minimal absorption and low systemic bioavailability, elobixibat is generally well tolerated and may offer the added benefit of improving serum lipid profiles through bile acid depletion.[1]

Three-week-old male C57BL/6J mice were randomly divided into two groups (Fig. 1a): (1) CDHF diet + DEN (control group) and (2) CDHF diet + DEN + elobixibat (elobixibat group) groups. The mice received a single intraperitoneal injection of 25-mg/kg DEN at 3 weeks of age. Then, they were fed a standard diet until they reached 8 weeks of age. For the next 20 weeks, mice in the control group were fed a CDHF diet (60 kcal% fat), while those in the elobixibat group were fed a CDHF diet mixed with elobixibat. The animals were housed in a controlled environment (temperature 23 ± 1 °C, humidity 50 ± 10%, 12-h light/dark cycle) at the animal facility with unlimited access to food and water.[2]

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Dose setting for elobixibat[2]
Elobixibat was calculated to be 0.27 mg/kg/day. This study used animals (mean body weight of 23 g) based on the previously published data. The 50% inhibitory concentration of human IBAT is 0.53 nmol/L, and that of mouse IBAT is 0.13 nmol/L. Therefore, the inhibitory activity is four times higher in mice than in humans. The concentration of elobixibat in mice at 70% effective dose is 2.7 mg/kg; while at 50% effective dose, it is 0.27 (70% × [0.023/60])0.33 = 2.23 mg/kg; this would be 110 mg/day for a 50-kg human, 11 times the amount normally used. Therefore, we set our effective capacity at 50%: 0.27 (50%) × [0.023/60])0.33 = 0.223 mg/kg. A CDHF + elobixibat diet containing 3 mg elobixibat per kg of CDHF diet was created and used based on the mean expected body weight and expected food intake.[2]

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Elobixibat (1.2 mg/kg/day) was administered for the final 4 weeks of this period (elobixibat group). At the end of the study period, the mice were euthanized by inhalation of carbon dioxide.[2]
Doses of 0.2, 0.6, or 1.2 mg/kg of elobixibat were administered for 4 weeks, 5 days per week, by oral gavage. Both the control group and the MCD-NASH group were administered PBS on the same schedule by oral gavage. There were no clear effects of 0.2 mg/kg or 0.6 mg/kg (data not shown), but beneficial effects were observed at the 1.2 mg/kg/day dose. This concentration is 4–6 times the dosage for human. According to “Drug Interview Form of Elobixibat”, elobixibat showed strong inhibitory activity to human IBAT, which was about four times more than that of mouse IBAT. Therefore, a dose of 1.2 mg/kg/day in mice is considered equivalent to 0.3 mg/kg/day in human. We evaluated the effects of this dose on the severity of NASH, cytokine production, the intestinal microbiota, and the intestinal TJs in the mice. No diarrhea was observed during the rearing period, and there was no difference in body weight between the NASH and elobixibat groups at the end of the experiment.[2]

[1]. Elobixibat for the treatment of constipation. Expert Opin Investig Drugs. 2013 Feb; 22(2):277-84.

Elobixibat has been used in trials studying the treatment and basic science of Dyslipidemia, Constipation, Chronic Constipation, Functional Constipation, and Chronic Idiopathic Constipation.

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Drug Indication: Treatment of chronic constipation

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Elobixibat (formerly A3309) is a first-in-class ileal bile acid transporter (IBAT) inhibitor for treatment of chronic idiopathic constipation (CIC; syn functional constipation). CIC affects up to 25% of the general population; and up to a half are unsatisfied with current therapies. There is an unmet need for safe and effective drugs to treat CIC. Areas covered: The authors present: i) an overview of Phase II clinical trials of elobixibat in CIC, based on peer-reviewed literature and congress presentations and ii) an evaluation of the efficacy and mechanism of action of elobixibat in the treatment of CIC. Expert opinion: Elobixibat provides a novel approach to treat chronic constipation via IBAT inhibition with enhanced delivery of bile acids to the colon. Pharmacodynamic studies show that it accelerates colonic transit, increases stool frequency, loosens stool consistency and relieves constipation-related symptoms in CIC patients. These beneficial effects are maintained for a minimum of 8 consecutive weeks of treatment. With minimal absorption and low systemic bioavailability, elobixibat is generally well tolerated and may offer the added benefit of improving serum lipid profiles through bile acid depletion.[1]

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Elevated bile acid levels have been associated with liver tumors in fatty liver. Ileal bile acid transporter inhibitors may inhibit bile acid absorption in the distal ileum and increase bile acid levels in the colon, potentially decreasing the serum and hepatic bile acid levels. This study aimed to investigate the impact of these factors on liver tumor. Methods: C57BL/6J mice received a one-time intraperitoneal injection of 25-mg/kg diethylnitrosamine. They were fed a choline-deficient high-fat diet for 20 weeks starting from 8 weeks of age, with or without elobixiba[2]

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Recent studies have suggested that several types of toxic bile acids (BAs) are involved in the pathogenesis of non-alcoholic steatohepatitis (NASH). In the present study, we aimed to determine whether elobixibat, an ileal bile acid transporter (IBAT) inhibitor, would ameliorate NASH in mice. Methods: C57BL/6N mice were fed a methionine and choline-deficient (MCD) to induce NASH or standard diet as control for 8 weeks (n = 5 per group). The MCD diet-fed mice were administered elobixibat 5 days a week for 4 weeks by gavage (n = 5). The effects of the treatments on liver histopathology, proinflammatory cytokine concentrations, intestinal epithelial tight junctions, and the intestinal microbial composition were then assessed.[3]

C36H47N3O8S2

713.9037

713.28

1633824-78-8

Elobixibat;439087-18-0

121494007

White to off-white solid powder

4

10

16

49

1140

1

S1(C2=CC(=C(C=C2N(C2C=CC=CC=2)CC(CCCC)(CCCC)C1)SC)OCC(N[C@@H](C(NCC(=O)O)=O)C1C=CC=CC=1)=O)(=O)=O.O

VARDBGNECHECBX-MDYNBEAQSA-N

InChI=1S/C36H45N3O7S2.H2O/c1-4-6-18-36(19-7-5-2)24-39(27-16-12-9-13-17-27)28-20-30(47-3)29(21-31(28)48(44,45)25-36)46-23-32(40)38-34(26-14-10-8-11-15-26)35(43)37-22-33(41)42;/h8-17,20-21,34H,4-7,18-19,22-25H2,1-3H3,(H,37,43)(H,38,40)(H,41,42);1H2/t34-;/m1./s1

2-[[(2R)-2-[[2-[(3,3-dibutyl-7-methylsulfanyl-1,1-dioxo-5-phenyl-2,4-dihydro-1λ6,5-benzothiazepin-8-yl)oxy]acetyl]amino]-2-phenylacetyl]amino]acetic acid;hydrate

elobixibat hydrate; Elobixibat monohydrate; Elobixibat hydrate [MI]; C8YTS56FNG; UNII-C8YTS56FNG; 1633824-78-8; Elobixibat hydrate (JAN); Glycine, (2R)-N-(2-((3,3-dibutyl-2,3,4,5-tetrahydro-7-(methylthio)-1,1-dioxido-5-phenyl-1,5-benzothiazepin-8-yl)oxy)acetyl)-2-phenylglycyl-, hydrate (1:1);

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.)