Absorption, Distribution and Excretion
Maximum plasma concentrations of cilazaprilat are reached within two hours after administration of cilazapril.
Cilazaprilat is eliminated unchanged by the kidneys. The total urinary recovery of cilazaprilat after intravenous administration of 2.5 mg is 91%.
Total clearance is 12.3 L/h and renal clearance is 10.8 L/h. The total urinary recovery of cilazaprilat following the oral administration of 2.5 mg cilazapril is 52.6%.

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Biological Half-Life
Half-lives for the periods 1 to 4 hours and 1 to 7 days after the intravenous administration of 2.5 mg cilazaprilat are 0.90 and 46.2 hours respectively.

Protein Binding
Maximum ACE inhibition is greater than 90% after 1 to 5 mg cilazapril. Maximum ACE inhibition is 70 to 80% after 0.5 mg cilazapril. Dose proportionality is observed following the administration of 1 to 5 mg cilazapril. Apparent non-proportionality is observed at 0.5 mg reflective of the binding to ACE. The higher doses of cilazapril are associated with longer duration of maximum ACE inhibition.

J Pharmacol Sci.2004 Jan;94(1):67-72;Life Sci.1999;64(3):PL27-39.

Cilazapril is a pyridazinodiazepine resulting from the formal condensation of the carboxy group of cilazaprilat with ethanol. It is a drug used in the treatment of hypertension and heart failure. It has a role as a prodrug, an antihypertensive agent and an EC 3.4.15.1 (peptidyl-dipeptidase A) inhibitor. It is an ethyl ester, a pyridazinodiazepine and a dicarboxylic acid monoester. It is functionally related to a Cilazaprilat.
Cilazapril is an ACE inhibtor class drug used in the treatment of hypertension and heart failure. It belongs to the angiotensin-converting enzyme inhibitors (ACE inhibitors) class of drugs. It is a prodrug that is hydrolyzed after absorption to its main metabolite cilazaprilat. It is branded as Inhibace in Canada and other countries, Vascace and Dynorm in a number of European countries, among many other names. None of these varieties are available in the United States.
Cilazapril Monohydrate is a pyridazine angiotensin-converting enzyme (ACE) inhibitor with antihypertensive activity. As a prodrug, cilazapril is rapidly metabolized in the liver to cilazaprilat; cilazaprilat competitively binds to and inhibits ACE, thereby blocking the conversion of angiotensin I to angiotensin II. This prevents the potent vasoconstrictive actions of angiotensin II, resulting in vasodilation. Cilazaprilat also decreases angiotensin II-induced aldosterone secretion by the adrenal cortex, which leads to an increase in sodium excretion and subsequently increases water outflow.
Cilazapril Anhydrous is the anhydrous form of the pyridazine angiotensin-converting enzyme (ACE) inhibitor cilazapril with antihypertensive activity. As a prodrug cilazapril is rapidly metabolized in the liver to cilazaprilat; cilazaprilat competitively binds to and inhibits ACE, thereby blocking the conversion of angiotensin I to angiotensin II. This prevents the potent vasoconstrictive actions of angiotensin II, resulting in vasodilation. Cilazaprilat also decreases angiotensin II-induced aldosterone secretion by the adrenal cortex, which leads to an increase in sodium excretion and subsequently increases water outflow.
One of the ANGIOTENSIN-CONVERTING ENZYME INHIBITORS (ACE inhibitors) used for hypertension. It is a prodrug that is hydrolyzed after absorption to its main metabolite cilazaprilat.

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Drug Indication
Cilazapril is an ACE inhibtor class drug used in the treatment of hypertension and heart failure.
FDA Label

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Mechanism of Action
Cilazapril is a pyridazine ACE inhibitor. It competes with angiotensin I for binding at the angiotensin-converting enzyme, blocking the conversion of angiotensin I to angiotensin II. As angiotensin II is a vasoconstrictor and a negative feedback mediator for renin activity, lower angiotensin II levels results in a decrease in blood pressure, an increase in renin activity, and stimulation of baroreceptor reflex mechanisms. Kininase II, an enzyme which degrades the vasodilator bradykinin, is identical to ACE and may also be inhibited.

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Pharmacodynamics
Cilazapril inhibits the production angiotensin II. By doing so, it decreases sodium and water reabsorption (via aldosterone) and it decreases vasoconstriction. The combined effect of this is a decrease in vascular resistance, and therefore, blood pressure. The absolute bioavailability of cilazaprilat after oral administration of cilazapril is 57% based on urinary recovery data. (The absolute bioavailability of cilazaprilat after oral administration of cilazaprilat is 19%.) Ingestion of food immediately before the administration of cilazapril reduces the average peak plasma concentration of cilazaprilat by 29%, delays the peak by one hour and reduces the bioavailability of cilazaprilat by 14%. These pharmacokinetic changes have little influence on plasma ACE inhibition.

C22H31N3O5

417.5

417.226

88768-40-5

Cilazapril monohydrate;92077-78-6

56330

Typically exists as solid at room temperature

1.26g/cm3

598.1ºC at 760 mmHg

95-97ºC

315.5ºC

3.73E-15mmHg at 25°C

1.591

1.862

2

7

9

30

608

3

C([C@@H]1CCCN2CCC[C@@H](C(N12)=O)N[C@H](C(=O)OCC)CCC1C=CC=CC=1)(=O)O

HHHKFGXWKKUNCY-FHWLQOOXSA-N

InChI=1S/C22H31N3O5/c1-2-30-22(29)18(13-12-16-8-4-3-5-9-16)23-17-10-6-14-24-15-7-11-19(21(27)28)25(24)20(17)26/h3-5,8-9,17-19,23H,2,6-7,10-15H2,1H3,(H,27,28)/t17-,18-,19-/m0/s1

(4S,7S)-7-[[(2S)-1-ethoxy-1-oxo-4-phenylbutan-2-yl]amino]-6-oxo-1,2,3,4,7,8,9,10-octahydropyridazino[1,2-a]diazepine-4-carboxylic acid

Ro 31 2848 Ro 31-2848 Ro 312848 Ro-31-2848 Ro312848Cilazapril Vascace Cilazaprilum UNII-8Q9454114Q

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.)