Identification
NamePemirolast
Accession NumberDB00885  (APRD00394)
TypeSmall Molecule
GroupsApproved
Description

Pemirolast potassium is a slightly yellow powder that is soluble in water. It is a mast cell stabilizer that acts as an antiallergic agent. As an ophthalmic aqueous sterile solution, pemirolast is used for the prevention of itching of the eyes caused by allergies such as hay fever, and allergic conjunctivitis. Pemirolast is potentially useful for prophylaxis of pulmonary hypersensitivity reactions to drugs such as paclitaxel.

Structure
Thumb
Synonyms
Pemirolast
Pemirolastum
Pemirox
External IDs BMY 26517 / DE 068 / TBX
Product Ingredients
IngredientUNIICASInChI KeyDetails
Pemirolast potassium497A17OUUE 100299-08-9NMMVKSMGBDRONO-UHFFFAOYSA-NDetails
Approved Prescription ProductsNot Available
Approved Generic Prescription ProductsNot Available
Approved Over the Counter ProductsNot Available
Unapproved/Other Products Not Available
International Brands
NameCompany
AlamastSanten Pharmaceutical Co.
AlegysalSanten Pharmaceutical Co.
Brand mixturesNot Available
Categories
UNII2C09NV773M
CAS number69372-19-6
WeightAverage: 228.2101
Monoisotopic: 228.075958908
Chemical FormulaC10H8N6O
InChI KeyHIANJWSAHKJQTH-UHFFFAOYSA-N
InChI
InChI=1S/C10H8N6O/c1-6-3-2-4-16-9(6)11-5-7(10(16)17)8-12-14-15-13-8/h2-5H,1H3,(H,12,13,14,15)
IUPAC Name
9-methyl-3-(2H-1,2,3,4-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one
SMILES
CC1=CC=CN2C(=O)C(=CN=C12)C1=NNN=N1
Pharmacology
Indication

For the prevention of itching of the eyes caused by allergies such as hay fever, and allergic conjunctivitis

Structured Indications Not Available
Pharmacodynamics

Pemirolast is used for the prophylactic treatment of itching of the eye associated with allergic conjunctivitis. Pemirolast potassium is a mast cell stabilizer that inhibits the in vivo Type I immediate hypersensitivity reaction. Pemirolast inhibits the antigen-induced release of inflammatory mediators (e.g., histamine, leukotriene C4, D4, E4) from human mast cells. Allergic reactions lead to cell-degranulation and the release of histamine (and other chemical mediators) from the mast cell or basophil. Once released, histamine can react with local or widespread tissues through histamine receptors. Histamine, acting on H1-receptors, produces pruritis and vasodilatation (allowing blood fluids to enter the area to cause swelling). Pemirolast is a histamine H1 antagonist. It competes with histamine for the normal H1-receptor sites on effector cells of blood vessels to provide effective, temporary relief of watery and itchy eyes.

Mechanism of action

Pemirolast binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Pemirolast has also been observed to inhibit antigen-stimulated calcium ion influx into mast cells through the blockage of calcium channels. Pemirolast inhibits the chemotaxis of eosinophils into ocular tissue, and prevents inflammatory mediator release from human eosinophils.

Related Articles
AbsorptionNot Available
Volume of distributionNot Available
Protein bindingNot Available
Metabolism

Hepatic (Ophthalmic)

Route of elimination

Following topical administration, about 10-15% of the dose was excreted unchanged in the urine.

Half life

4.5 hours (Ophthalmic)

ClearanceNot Available
ToxicityNot Available
Affected organisms
  • Humans and other mammals
PathwaysNot Available
Pharmacogenomic Effects/ADRs Not Available
Interactions
Drug Interactions
DrugInteractionDrug group
2,5-Dimethoxy-4-ethylamphetamine2,5-Dimethoxy-4-ethylamphetamine may decrease the sedative activities of Pemirolast.Experimental, Illicit
3,4-Methylenedioxyamphetamine3,4-Methylenedioxyamphetamine may decrease the sedative activities of Pemirolast.Experimental, Illicit
3,4-Methylenedioxymethamphetamine3,4-Methylenedioxymethamphetamine may decrease the sedative activities of Pemirolast.Experimental, Illicit
4-Bromo-2,5-dimethoxyamphetamine4-Bromo-2,5-dimethoxyamphetamine may decrease the sedative activities of Pemirolast.Experimental, Illicit
AmphetamineAmphetamine may decrease the sedative activities of Pemirolast.Approved, Illicit
BenzphetamineBenzphetamine may decrease the sedative activities of Pemirolast.Approved, Illicit
Benzylpenicilloyl PolylysinePemirolast may decrease effectiveness of Benzylpenicilloyl Polylysine as a diagnostic agent.Approved
BetahistineThe therapeutic efficacy of Betahistine can be decreased when used in combination with Pemirolast.Approved
ChlorphentermineChlorphentermine may decrease the sedative activities of Pemirolast.Illicit, Withdrawn
DextroamphetamineDextroamphetamine may decrease the sedative activities of Pemirolast.Approved, Illicit
DiethylpropionDiethylpropion may decrease the sedative activities of Pemirolast.Approved, Illicit
HyaluronidaseThe therapeutic efficacy of Hyaluronidase can be decreased when used in combination with Pemirolast.Approved, Investigational
HydroxyamphetamineHydroxyamphetamine hydrobromide may decrease the sedative activities of Pemirolast.Approved
LisdexamfetamineLisdexamfetamine may decrease the sedative activities of Pemirolast.Approved, Investigational
MephedroneMephedrone may decrease the sedative activities of Pemirolast.Investigational
MephentermineMephentermine may decrease the sedative activities of Pemirolast.Approved
MethamphetamineMethamphetamine may decrease the sedative activities of Pemirolast.Approved, Illicit
MMDAMMDA may decrease the sedative activities of Pemirolast.Experimental, Illicit
PhenterminePhentermine may decrease the sedative activities of Pemirolast.Approved, Illicit
PseudoephedrinePseudoephedrine may decrease the sedative activities of Pemirolast.Approved
RitobegronRitobegron may decrease the sedative activities of Pemirolast.Investigational
Food InteractionsNot Available
References
Synthesis Reference

Graziano Castaldi, "Process for the preparation of high purity pemirolast." U.S. Patent US20030032805, issued February 13, 2003.

US20030032805
General References
  1. Tinkelman DG, Berkowitz RB: A pilot study of pemirolast in patients with seasonal allergic rhinitis. Ann Allergy. 1991 Feb;66(2):162-5. [PubMed:1994787 ]
External Links
ATC CodesNot Available
AHFS CodesNot Available
PDB EntriesNot Available
FDA labelDownload (372 KB)
MSDSNot Available
Clinical Trials
Clinical Trials
PhaseStatusPurposeConditionsCount
1CompletedNot AvailableHealthy Volunteers1
Pharmacoeconomics
Manufacturers
  • Santen inc
Packagers
Dosage formsNot Available
Prices
Unit descriptionCostUnit
Alamast 0.1% drops11.39USD ml
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Patents
Patent NumberPediatric ExtensionApprovedExpires (estimated)
US5034230 No1994-07-022011-07-02Us
Properties
StateSolid
Experimental Properties
PropertyValueSource
logP0Not Available
Predicted Properties
PropertyValueSource
Water Solubility0.462 mg/mLALOGPS
logP0.13ALOGPS
logP1.46ChemAxon
logS-2.7ALOGPS
pKa (Strongest Acidic)5.8ChemAxon
pKa (Strongest Basic)-1.4ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count5ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area87.13 Å2ChemAxon
Rotatable Bond Count1ChemAxon
Refractivity63.35 m3·mol-1ChemAxon
Polarizability21.96 Å3ChemAxon
Number of Rings3ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted ADMET features
PropertyValueProbability
Human Intestinal Absorption+1.0
Blood Brain Barrier+0.9766
Caco-2 permeable+0.6032
P-glycoprotein substrateNon-substrate0.6874
P-glycoprotein inhibitor INon-inhibitor0.7029
P-glycoprotein inhibitor IINon-inhibitor0.9336
Renal organic cation transporterNon-inhibitor0.8165
CYP450 2C9 substrateNon-substrate0.7256
CYP450 2D6 substrateNon-substrate0.8314
CYP450 3A4 substrateSubstrate0.5485
CYP450 1A2 substrateInhibitor0.874
CYP450 2C9 inhibitorNon-inhibitor0.8783
CYP450 2D6 inhibitorNon-inhibitor0.8729
CYP450 2C19 inhibitorNon-inhibitor0.8134
CYP450 3A4 inhibitorNon-inhibitor0.543
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.5112
Ames testAMES toxic0.5453
CarcinogenicityNon-carcinogens0.8916
BiodegradationNot ready biodegradable0.9965
Rat acute toxicity2.3619 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9391
hERG inhibition (predictor II)Non-inhibitor0.8932
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397 )
Spectra
Mass Spec (NIST)Not Available
SpectraNot Available
Taxonomy
DescriptionThis compound belongs to the class of chemical entities known as pyridopyrimidines. These are compounds containing a pyridopyrimidine, which consists of a pyridine fused to a pyrimidine. Pyridine is 6-membered ring consisting of five carbon atoms and a nitrogen atom. Pyrimidine is a 6-membered ring consisting of four carbon atoms and two nitrogen centers at the 1- and 3- ring positions.
KingdomChemical entities
Super ClassOrganic compounds
ClassOrganoheterocyclic compounds
Sub ClassPyridopyrimidines
Direct ParentPyridopyrimidines
Alternative ParentsPyrimidones / Methylpyridines / Tetrazoles / Heteroaromatic compounds / Lactams / Azacyclic compounds / Organopnictogen compounds / Organooxygen compounds / Organonitrogen compounds / Organic oxides
SubstituentsPyridopyrimidine / Pyrimidone / Methylpyridine / Pyridine / Pyrimidine / Azole / Tetrazole / Heteroaromatic compound / Lactam / Azacycle
Molecular FrameworkAromatic heteropolycyclic compounds
External DescriptorsNot Available
Drug created on June 13, 2005 07:24 / Updated on July 18, 2017 16:54