Clopidogrel is a prodrug which is converted into active metabolite by cytochrome P450 isoenzyme, CYP2C19. Numerous polymorphisms of CYP2C19 are reported, and a strong link exists between loss-of-function (LOF) or gain-of-function polymorphisms, clopidogrel metabolism, and clinical outcome. Hence, a fully automated point-of-care CYP2C19 genotyping assay is more likely to bring personalized antip...

OBJECTIVE The aim of the present study was to investigate whether the genetic polymorphism of CYP2C19 plays a role in susceptibility to bronchial asthma. SUBJECTS AND METHODS 104 healthy individuals who visited our hospital, including hospital staff, and 97 patients with bronchial asthma (62 atopic and 35 nonatopic) participated in this study. CYPC19*2 and CYP21C9*3 alleles were detected by u...

AIMS To examine the relationship between proguanil metabolism and the number of mutations in CYP2C19 by comparing the CYP2C19 genotype and proguanil phenotype of 10 subjects. METHODS Partial clearance and urinary metabolic ratio data were obtained from a previous study of 10 subjects [5]. Analysis of CYP2C19 genotypes was performed using PCR amplification followed by restriction endonuclease ...

AIMS The aim was to explore the role of CYP2C19 polymorphism in short-term rabeprazole-based triple therapy against Helicobacter pylori infection. METHODS Patients with H. pylori infection were tested for CYP2C19 genotype as poor metabolizers (PMs) or extensive metabolizers (EMs, homozygous EM or heterozygous EM) and given rabeprazole for 7 days. Antibiotics (clarithromycin and amoxicillin) w...

Cytochrome P4502C19 (CYP2C19) is an important drug-metabolizing enzyme involved in the biotransformation of, for example, proton pump inhibitors and antidepressants. Several in vivo studies have shown that the CYP2C19 activity is inhibited by oral contraceptives, which can cause important drug interactions. The underlying molecular mechanism has been suggested to be competitive inhibition. Howe...

Cytochrome P450s (CYPs) are responsible for approximately 75% of the phase Idependent drug metabolism. Several important polymorphisms in these enzymes are known to significantly affect the individual drug response. CYP2C9 and CYP2C19 are polymorphically expressed CYP family members which are responsible for the metabolism of many different clinically important drugs, e.g. anticoagulants, antid...

BACKGROUND Despite the proven clinical effect of oral antiplatelet drugs, a considerable number of patients do not have an adequate response to clopidogrel. The aim of our study was to determine the influence of CYP2C19*2 loss-of-function variant allele on clopidogrel responsiveness in patients with carotid artery stenosis. METHODS One hundred and twelve patients with carotid artery stenosis ...

Background Patients with hepatic diseases are treated with numerous drugs metabolized by cytochrome P450. Objective To evaluate the frequencies of CYP2C19 variant alleles (*2, *3, and *17), genotypes, and phenotypes, and the relationship between the frequency of these alleles and the underlying hepatic diseases among patients with advanced liver diseases who were candidates for liver transpla...

Genetic variation in the cytochrome P450 2C19 (CYP2C19) gene has been documented gradually as the determinant conversion and variability in the antiplatelet effect of clopidogrel. The aims of this study were to determine the prevalence of clinically relevant allele variants (CYP2C19*2, CYP2C19*3, and CYP2C19*17) in a Thai study population, and finally determine whether the allele distributes an...

Clopidogrel is an inhibitor of platelet-aggregation used in the prevention of secondary stroke. The molecule is activated by the cytochrome P450 2C19 (CYP2C19) enzyme. The frequent CYP2C19*2 point mutation causes loss of enzyme function, a decreased (heterozygous form) or blocked (homozygous form) formation of the active molecule. Thus, for a patient harboring a mutated allele, clopidogrel does...