H+/K+-ATPase (IC50 = 19 nM)

Vonoprazan (0.1 nM-10 μM; 30 minutes) activates porcine gastric H+, K+-ATPase in a concentration-dependent manner [2]. Vonoprazan does not block Na+,K+-ATPase activity, even at doses 500 times greater than the IC50 values for gastric H+,K+-ATPase activity[2].

Rats' baseline and 2-deoxy-D-glucose (200 mg/kg; sc)-stimulated stomach acid production is totally inhibited by vonoprazan (1-4 mg/kg; po) at a dose of 4 mg/kg[2].

Proton Potassium Adenosine Triphosphatase (H+,K+-ATPase) Inhibitory Activity Test [1]
Accordinpg to the method of Wallmark et al., a gastric mucosal membrane microsomal fraction was prepared from the stomach of swine. First, the stomach was removed, washed with tap water, and immersed in 3 mol/L brine, and the surface of the mucosal membrane was wiped with a paper towel. The gastric mucosal membrane was detached, chopped, and homogenized in a 0.25 mol/L saccharose solution (pH 6.8) containing 1 mmol/L EDTA and 10 mmol/L tris-hydrochloric acid using polytron (Kinematica). The obtained homogenate was centrifuged at 20000g for 30 min and the supernatant was centrifuged at 100000g for 90 min. The precipitate was suspended in 0.25 mol/L saccharose solution, superimposed on a 0.25 mol/L saccharose solution containing 7.5% Ficoll, and centrifuged at 100000g for 5 h. The fraction containing the interface between the both layers was recovered, and centrifugally washed with 0.25 mol/L saccharose solution. The obtained microsomal fraction was used as a proton, potassium adenosine triphosphatase standard product. To 40 μL of a 50 mmol/L HEPES-Tris buffer (5 mmol/L magnesium chloride, 10 mmol/L potassium chloride, 10 μmol/L valinomycin, pH 6.5) containing 2.5 μg/mL (based on the protein concentration) of the enzyme standard product was added a test compound (5 μL) dissolved in a 10% aqueous dimethyl sulfoxide solution, and the mixture was incubated at 37 °C for 30 min. The enzyme reaction was started by adding 5 μL of a 2 mmol/L adenosine triphosphate Tris salt solution (50 mmol/L HEPES-Tris buffer (5 mmol/L magnesium chloride, pH 6.5)). The enzyme reaction was carried out at 37 °C for 20 min, and 15 μL of a malachite green solution (0.12% malachite green solution in sulfuric acid (2.5 mol/L), 7.5% ammonium molybdate, and 11% Tween 20 were mixed at a ratio of 100:25:2) was added to quench the reaction. After the mixture was allowed to stand at room temperature for 15 min, the resulting reaction product of inorganic phosphorus with malachite green was colorimetrically determined at a wavelength of 610 nm. In addition, the amount of the inorganic phosphoric acid in the reaction solution free of potassium chloride was measured in the same manner, which was subtracted from the inorganic phosphoric acid amount in the presence of potassium chloride to determine the H+,K+-ATPase activity. The inhibitory rate (%) was determined from the activity value of the control and the activity values of various concentrations of the test compound, and the 50% inhibitory concentration (IC50) of the H+,K+-ATPase activity was determined.

Animal/Disease Models: Male 7- or 8weeks old SD (Sprague-Dawley) rat[2]
Doses: 0.5 mg/kg, 1 mg/kg, 2 mg/kg, 4 mg/kg
Route of Administration: Oral administration
Experimental Results: Inhibited basal gastric acid secretion in a dose-dependent manner.

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Inhibiton of Histamine-Stimulated Acid Secretion in Anesthetized Rats (iv) [1]
Seven-week-old male Jcl:Sprague Dawley (SD) rats were used. The animals were fasted for 24 h but had free access to water before the experiment. The pylorus was ligated after anesthetization with urethane (1.2 g/kg, ip), and the abdomen was closed. Drugs and the vehicle were given intravenously just after the pylorus ligation. Three minutes later, histamine·2HCl (30 mg/kg per 10 mL) was injected subcutaneously. Three hours after histamine administration, the rats were sacrificed by CO2 asphyxiation and the stomachs were removed. The gastric contents were collected and centrifuged at 3000 rpm for 10 min. The volume of each sample was measured and the acid concentration was determined by automatic titration to pH 7.0 with 0.1 mol/L NaOH, and the total acid output during the 3 h period (μequiv/(3 h)) was calculated.

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Histamine-Stimulated Acid Secretion in Heidenhain Pouch Dogs [1]
Drugs and the vehicle were given orally (0.2 mL/kg) to the dogs in a blind manner. Histamine·2HCl (30 μg/kg) was injected subcutaneously 1 day before and 1, 3, 6, 24, and 48 h after drugs and the vehicle administration. The gastric juice from the pouch was collected continuously for three consecutive 30 min periods after each dosing with histamine·2HCl. The volume of gastric juice was measured, and the acid concentration was determined by automatic titration to pH 7.0 with 0.1 mol/L NaOH solution. The total acid output during the 90 min period (μequiv/(90 min)) from each time was calculated and expressed as a percentage of the predosing value measured 1 day before the administration.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No information is available on the clinical use of vonoprazan during breastfeeding. Because of liver damage that occurred in nursing rodents, the manufacturer recommends that nursing mothers should pump and discard human milk while taking and for 2 days after the last dose. An alternate drug may be preferred.

◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.

◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
In healthy subjects, the plasma protein binding of vonoprazan ranges from 85% to 88%. At plasma concentrations between 0.1 and 10 mcg/mL, the plasma protein binding of vonoprazan is independent of concentration.

[1]. Discovery of a novel pyrrole derivative 1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine fumarate (TAK-438) as a potassium-competitive acid blocker (P-CAB). J Med Chem, 2012, 55(9), 4446-4456.

[2]. 1-[5-(2-Fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine monofumarate (TAK-438), a novel and potent potassium-competitive acid blocker for the treatment of acid-related diseases. J Pharmacol Exp Ther, 2010, 335(1), 231-238.

[3]. Role of Vonoprazan in Helicobacter pylori Eradication Therapy in Japan. Front Pharmacol. 2019 Jan 15;9:1560.

Vonoprazan Fumarate is the fumarate salt form of vonoprazan, a pyrrole derivative and reversible potassium-competitive acid blocker (P-CAB), with potential antacid activity. Upon administration, vonoprazan specifically and competitively binds to the gastric hydrogen-potassium ATPase (H+/K+ ATPase) proton pump at or, more likely, near its potassium ion (K+) binding site and sterically inhibits K+ binding. This blocks the activation of the H+/K+ ATPase by K+, inhibits the proton pump and prevents gastric acid secretion, thereby lowering gastric acid levels.
See also: Vonoprazan (has active moiety); Amoxicillin; clarithromycin; vonoprazan fumarate (component of); Amoxicillin; vonoprazan fumarate (component of).

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In our pursuit of developing a novel and potent potassium-competitive acid blocker (P-CAB), we synthesized pyrrole derivatives focusing on compounds with low log D and high ligand-lipophilicity efficiency (LLE) values. Among the compounds synthesized, the compound 13e exhibited potent H(+),K(+)-ATPase inhibitory activity and potent gastric acid secretion inhibitory action in vivo. Its maximum efficacy was more potent and its duration of action was much longer than those of proton pump inhibitors (PPIs). Therefore, compound 13e (1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine fumarate, TAK-438) was selected as a drug candidate for the treatment of gastroesophageal reflux disease (GERD), peptic ulcer, and other acid-related diseases. [1]

C17H16FN3O2S

345.3912

345.094

C, 59.12; H, 4.67; F, 5.50; N, 12.17; O, 9.26; S, 9.28

881681-00-1

Vonoprazan Fumarate;881681-01-2;Vonoprazan hydrochloride;1957202-44-6

45375887

White to off-white solid powder

1.3±0.1 g/cm3

530.3±60.0 °C at 760 mmHg

274.5±32.9 °C

0.0±1.4 mmHg at 25°C

1.622

2.74

3

9

7

32

629

0

CNCC1=CN(C(=C1)C2=CC=CC=C2F)S(=O)(=O)C3=CN=CC=C3.C(=C/C(=O)O)\C(=O)O

ROGSHYHKHPCCJW-WLHGVMLRSA-N

InChI=1S/C17H16FN3O2S.C4H4O4/c1-19-10-13-9-17(15-6-2-3-7-16(15)18)21(12-13)24(22,23)14-5-4-8-20-11-14;5-3(6)1-2-4(7)8/h2-9,11-12,19H,10H2,1H3;1-2H,(H,5,6)(H,7,8)/b;2-1+

(E)-but-2-enedioic acid;1-[5-(2-fluorophenyl)-1-pyridin-3-ylsulfonylpyrrol-3-yl]-N-methylmethanamine

Vonoprazan; 881681-00-1; TAK-438 free base; Vonoprazan [INN]; Vonoprazan free base; UNII-1R5L3J156G; Vonoprazan [USAN]; 1R5L3J156G;

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)

DMSO : ~100 mg/mL (~289.53 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (7.24 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (7.24 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (7.24 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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