CYP2C19 UM

BACKGROUND: Venlafaxine (VEN) is a commonly utilized medication for alleviating depression and anxiety disorders. The presence of genetic polymorphisms gives rise to considerable variations in plasma concentrations across different phenotypes. This divergence in phenotypic responses leads to notable differences in both the efficacy and tolerance of the drug. PURPOSE: A physiologically based pharmacokinetic (PBPK) model for VEN and its metabolite O-desmethylvenlafaxine (ODV) to predict the impact of CYP2D6 and CYP2C19 gene polymorphisms on VEN pharmacokinetics (PK)...

Introduction: Preventing side effects is important to ensure optimal psychopharmacotherapy and therapeutic adherence among psychiatric patients. Obtaining the pharmacogenetic profile of CYP2C19 and CYP2D6 can play an important role in this. When the genotype-predicted phenotype shifts because of the use of co-medication, this is called phenoconversion. The aim was to study the influence of the pharmacogenetic (PGx) profile and phenoconversion on side effects experienced by psychiatric patients. Methods: A retrospective cohort study was performed using data from 117 patients from a psychiatric outpatient clinic...

BACKGROUND: In patients with invasive fungal infection (IFI), the steady-state serum trough concentration ( C min ) of voriconazole (VCZ) is highly variable and can lead to treatment failure ( C min < 0.5 mg/L) and toxicity ( C min ≥ 5.0 mg/L). However, It remains challenging to determine the ideal maintenance dose to achieve the desired C min level quickly. AIMS: This randomized, prospective observational single-center study aimed to identify factors affecting VCZ- C min and maintenance dose and create an algorithmic model to predict the necessary maintenance dose...

Objective: To investigate the relationship between genetic polymorphisms of cytochrome P450 2C19 (CYP2C19) and the efficacy of Helicobacter pylori (Hp) eradication therapy in children. Methods: The retrospective cohort study was conducted on 125 children with gastroscopy and positive rapid urease test (RUT) from September 2016 to December 2018 who presented to the Children's Hospital of Zhejiang University School of Medicine due to gastrointestinal symptoms including nausea, vomiting, abdominal pain, bloating, acid reflux, heartburn, chest pain, vomiting blood and melena...

Background Cytochrome P450 system is implicated in vascular pathologies, including stroke. Besides its role as a drug metabolizer, it also plays an important role in the metabolism of several endogenous substances like fatty acids, arachidonic acid, etc., which have pro-inflammatory effects. On the other hand, leptin and adiponectin are two of the most common adipose tissue-derived cytokines (adipokines), which are pro-inflammatory and anti-inflammatory in nature, respectively. Both of them are implicated in the pathogenesis of stroke...

In humans, omeprazole is metabolised by cytochrome P450 (CYP450) CYP2C19 and CYP3A4 with differences in CYP2C19 genotypes leading to variable response to therapy. Despite a wide use of omeprazole in horses with evidence of variable therapeutic efficiency, information regarding enzymatic metabolism is not currently available. This study aims to describe the in vitro kinetics of omeprazole metabolism and determine which enzyme(s) are responsible for omeprazole metabolism in horses. Omeprazole (0-800 uM) was incubated with liver microsomes and a panel of equine recombinant CYP450s (eq-rCYP)...

BACKGROUND: It is essential to investigate the prevalence of CYP2C19 alleles that affect drug metabolism. This study measures the allelic and genotypic frequencies of CYP2C19 loss-of-function (LoF) alleles CYP2C19∗2, CYP2C19∗3, and gain-of-function (GoF) alleles CYP2C19∗17 in the general population. METHODOLOGY: The study involved 300 healthy subjects between the ages of 18 and 85 recruited by simple random sampling. Allele-specific touchdown PCR was employed to identify the various alleles...

The CYP2C19 gene, located in the CYP2C cluster, encodes the major drug metabolism enzyme CYP2C19. This gene is highly polymorphic and no-function ( CYP2C19*2 and CYP2C19 * 3 ), reduced function ( CYP2C19*9) and increased function ( CYP2C19*1 7) star alleles (haplotypes) are commonly used to predict CYP2C19 metabolic phenotypes. CYP2C19*17 and the genotype-predicted rapid (RM) and ultrarapid (UM) CYP2C19 metabolic phenotypes are absent or rare in several Native American populations. However, discordance between genotype-predicted and pharmacokinetically determined CYP2C19 phenotypes in Native American cohorts have been reported...

Pharmacogenetics has potential for optimizing use of psychotropics. CYP2D6 and CYP2C19 are two clinically relevant pharmacogenes in the prescribing of antidepressants. Using cases recruited from the Understanding Drug Reactions Using Genomic Sequencing (UDRUGS) study, we aimed to evaluate the clinical utility of genotyping CYP2D6 and CYP2C19 in antidepressant response. Genomic and clinical data for patients who were prescribed antidepressants for mental health disorders, and experienced adverse reactions (ADRs) or ineffectiveness, were extracted for analysis...

AIM: Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) remains the standard of care. CYP2C19 genetic polymorphisms cause variable Clopidogrel bioactivation. Increased function (CYP2C19*17) allele carriers (rapid metabolizers (RM) or ultrarapid metabolizers (UM)), are Clopidogrel hyper-responders, hence more susceptible to Clopidogrel related bleeding. Since current guidelines recommend against routine genotyping following PCI, data on the clinical utility of CYP2C19*17 genotype guided strategy are sparce...

BACKGROUND: The international drug agencies annotate pharmacogenes for many years. Pharmacogenetic testing is thus far only established in few settings, assuming that only few patients are actually affected by drug-gene interactions. METHODS: 108 hospitalized patients with major depressive disorder were genotyped for CYP1A2 , CYP2B6 , CYP2C8 , CYP2C9 , CYP2C19 , CYP2D6 , CYP3A4 , CYP3A5 , NAT2 , DPYD ; VKORC1 and TMTP . RESULTS: We found 583 (mean 5...

Background: This study used therapeutic drug monitoring (TDM) and CYP2C19 gene polymorphism analysis to explore the efficacy and safety of different doses of voriconazole (VCZ) for the clinical treatment of pediatric patients, with the aim of providing guidelines for individualized antifungal therapy in children. Methods: Our study enrolled 94 children with 253 VCZ concentrations. The genotyping of CYP2C19 was performed by polymerase chain reaction (PCR)-pyrosequencing...

BACKGROUND: The clinical impact of the functional CYP2C19 and CYP2D6 gene variants on antidepressant treatment in people with depression is not well studied. Here, we evaluate the utility of pharmacogenetic (PGx) testing in psychiatry by investigating the association between the phenotype status of the cytochrome P450 (CYP) 2C19/2D6 enzymes and the one-year risks of clinical outcomes in patients with depression with incident new-use of (es)citalopram, sertraline, or fluoxetine. METHODS: This study is a population-based cohort study of 17,297 individuals who were born between 1981 and 2005 with a depression diagnosis between 1996 and 2012...

WHAT IS KNOWN AND OBJECTIVE: For patients after percutaneous coronary interventions (PCI), clopidogrel combined with aspirin is a conventional dual antiplatelet therapy (DAPT) method. Because the genetic polymorphism of CYP2C19 gene leads to clopidogrel resistance, guidelines for antiplatelet recommendations in CYP2C19 of ultrarapid metabolizers (UM), extended metabolizers (EM) and poor metabolizers (PM) are clear. However, there is no clear recommendation as to whether ticagrelor or double dose clopidogrel is the best antiplatelet regimen for CYP2C19 of intermediate metabolizers (IM)...

The Dutch Pharmacogenetics Working Group (DPWG) guideline presented here, presents the gene-drug interaction between the genes CYP2C19 and CYP2D6 and antidepressants of the selective serotonin reuptake inhibitor type (SSRIs). Both genes' genotypes are translated into predicted normal metabolizer (NM), intermediate metabolizer (IM), poor metabolizer (PM), or ultra-rapid metabolizer (UM). Evidence-based dose recommendations were obtained, based on a structured analysis of published literature. In CYP2C19 PM patients, escitalopram dose should not exceed 50% of the normal maximum dose...

Many factors have been described to contribute to voriconazole (VCZ) interpatient variability in plasma concentrations, especially CYP2C19 genetic variability. In 2014, Hicks et al. presented data describing the correlation between VCZ plasma concentrations and CYP2C19 diplotypes in immunocompromised pediatric patients and utilized pharmacokinetic modeling to extrapolate a more suitable VCZ dose for each CYP2C19 diplotype. In 2017, in our hospital, a clinical protocol was developed for individualization of VCZ in immunocompromised patients based on preemptive genotyping of CYP2C19 and dosing proposed by Hicks et al...

OBJECTIVE: The objective of the present study was to estimate the frequency of CYP2C19 cytochrome variants *1, *2, *3 and *17 among Helicobacter pylori carriers from Manaus, Amazonas state, who were treated at Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD). METHODS: From the 78 recruited individuals who underwent upper gastrointestinal endoscopy with biopsy and histopathological test, 50 tested positive for H. pylori. Peripheral blood was collected from this group and CYP2C19 *2, *3 and *17 alleles were genotyped using qPCR...

OBJECTIVE: To study the use of CYP2C19 genotyping to guide P2Y12 inhibitor selection to maximize efficacy, and attenuate risk in appropriate patients who underwent PCI for CAD. METHODS: We performed a retrospective analysis of 868 patients with CAD who received CYP2C19 genotyping after PCI and changed P2Y12 inhibitor based on the results. Patients were divided into two groups based on clopidogrel metabolizer status. Group I: Intermediate (IM) and poor metabolizers (PM)...

BACKGROUND: Methadone use for the management of opioid dependency during pregnancy is commonplace. Methadone levels are altered during pregnancy due to changes in maternal physiology. Despite this, a paucity of data exist regarding the most appropriate optimal dosing regimens during pregnancy. METHODS: This study applied a pharmacokinetic modeling approach to examine gestational changes in R- and S-methadone concentrations in maternal plasma and fetal (cord) blood...

The antidiabetic drug gliclazide is partly metabolized by CYP2C19, the main enzyme involved in omeprazole metabolism. The aim of the study was to explore the interaction between omeprazole and gliclazide in relation to CYP2C19 phenotype using physiologically based pharmacokinetic (PBPK) modeling approach. Developed PBPK models were verified using in vivo pharmacokinetic profiles obtained from a clinical trial on omeprazole-gliclazide interaction in healthy volunteers, CYP2C19 normal/rapid/ultrarapid metabolizers (NM/RM/UM)...