CYP2C19 Gene Polymorphisms Research Articles

Association of cytochrome P450 CYP2C9 (rs1057910) gene polymorphism and ibuprofen response in preterm neonates diagnosed with patent ductus arteriosus

Background Patent ductus arteriosus (PDA) closure is one of the most significant changes necessary to transition to extrauterine life. The failure of closure in preterm infants has been associated with a variety of complications. Aim and objectives This study aim to investigate the correlation between cytochrome P450 CYP2C9 gene polymorphism and the response to ibuprofen treatment in preterm neonates with PDA. Subjects and methods This prospective study was conducted on 64 preterm neonates with patent ductus arteriosus (hsPDA). The neonates were treated with ibuprofen and diagnosed using clinical and echocardiographic examinations. The study was carried out at the Neonatal Intensive Care Unit (NICU), Pediatric Department, Kasr Alainy and ElMounira Pediatric Hospitals, Cairo University, in June 2018. Results A statistically significant difference in respiratory rate was observed between both groups ( p = 0.047). Additionally, there was a significant difference in the duration of treatment with ibuprofen ( p = 0.021). Treatment with ibuprofen had no impact on renal function parameters. The platelet count decreased after treatment with no statistical difference. Conclusion Use of Oral ibuprofen is a highly effective treatment for HsPDA in preterm neonates, demonstrating a remarkable success rate of 92.2% and fewer adverse effects. Whilst no correlation between the CYP2C9 (rs1057910) gene polymorphism and the efficacy of oral ibuprofen response, Other factors affecting the response of oral ibuprofen and subsequent PDA closure include gestational age, birth weight, Apgar score at 5 min, ductal diameter, RDS, and sepsis.

Characteristics and predictors of cardiovascular events related to CYP2C19 gene polymorphisms following acute coronary syndrome.

Cardiovascular events prognosis based on CYP2C19 gene polymorphisms had many applications in clinical practice. Assessed characteristics and predictive performance of cardiovascular events in acute coronary syndrome patients with CYP2C19 gene polymorphisms. The patients were analyzed for CYP2C19 gene polymorphisms by real-time polymerase chain reaction (PCR). The PCR worked with primers around the mutant, as well as two fluorescent probes, one specific for the normal allele and the other for the mutant allele, and cardiovascular events were followed at 3 months and 6 months. Patients with CYP2C19 gene polymorphism accounted for 48.6% of which CYP2C19 *1/*2 genotype had the highest proportion (31.7%). The normal metabolizer phenotype was the majority (51.4%), and the *1 allele proportion accounted for the most (72.2%). Patients with type 2 diabetes (HR: 3.082, 95% CI: 1.652-5.747, p < 0.001) and ST-segment elevation myocardial infarction (HR: 2.874, 95% CI: 1.528-5.404, p = 0.001) were independent prognostic factors for cardiovascular events at 90 days. Type 2 diabetes was an independent prognostic factor for cardiovascular events at 180 days (HR: 3.714, 95% CI: 1.557-8.862, p = 0.003). The CYP2C19 gene polymorphism was an independent prognostic factor of cardiovascular events at 90 days (HR: 1.965, 95% CI: 1.012-3.814, p = 0.046). However, at 180 days of analysis, the association between the CYP2C19 gene polymorphism was not significant (HR: 2.234, 95% CI: 0.862-5.789, p = 0.098). CYP2C19 gene polymorphism was an independent prognostic factor of cardiovascular events 90 days after acute coronary syndrome.

The relationship between CYP2C9 gene polymorphisms and azilsartan metabolism in vitro

ABSTRACT Background The gene polymorphisms of the CYP2C9, as well as the substrate specificity of the enzyme, result in different clearances for different substrates by CYP2C9 variants. Research designand methods The CYP2C9 wild type and 38 CYP2C9 variants, expressed in insectmicrosomes, were incubated with azilsartan. The resulting metabolite,O-desethyl azilsartan, was determined by HPLC-MS/MS. The enzyme kineticparameters of the 38 variants were calculated and compared with the wild type.Subsequently, we selected CYP2C9*1, *2, and *3 as target proteins for molecular docking with azilsartan to elucidate the mechanisms underlying changes in enzyme function. Results Compared with CYP2C9*1, three variants (CYP2C9*29, *39, and *49) exhibited markedlyincreased CLint values (from 170%-275%, *p < 0.05), whereas 28 variants exhibited significantly decreased CLint values (from 3-63%,*p < 0.05). The molecular docking results showed that the binding energy of CYP2C9*2 and *3 was lower than that of the wild type. Conclusion Thisassessment revealed the effect of CYP2C9 gene polymorphisms on azilsartan metabolism, establishing a theoretical basis for further in-vivo studies and clinical applications. This study will help expand the database of CYP2C9 gene-drug pairs and identify appropriate treatment strategies for azilsartan, contributing to the field of precision medicine.

The prognostic difference study on the individualized clopidogrel administration in Hmong and Dong patients based on the CYP2C19 gene polymorphism after percutaneous coronary intervention.

This study explored the distribution characteristics of CYP2C19 gene polymorphism among Hmong and Dong patients in the Qiandongnan region of Guizhou province after percutaneous coronary intervention (PCI). The aim was to assess the clinical impact of individualized clopidogrel administration based on CYP2C19 genotypes. A total of 208 patients were classified into ultra-fast, fast, intermediate, and slow metabolic groups. They were randomly assigned to clopidogrel individualized administration (IA) or conventional treatment (CA) groups. Patients were followed for 6 months to evaluate major adverse cardiovascular events (MACE) and adverse reactions. The CYP2C19 genotype distribution was in Hardy-Weinberg equilibrium, showing consistency in the population. While no significant ethnic differences were found in genotype and metabolic distribution, allele distribution varied, with Hmong patients exhibiting a higher proportion of CYP2C19*1 alleles than Dong patients. Following individualized administration, the IA group demonstrated lower incidences of non-fatal myocardial infarction and emergency revascularization compared to the CA group. Bleeding events were higher in the IA group, but the total MACE incidence was lower. No statistical difference in MACE and adverse drug reactions (ADR) was observed in the CA group across metabolic types, but MACE incidence was higher in intermediate and slow metabolic groups. In the IA group, no significant difference in MACE was noted among metabolic types, but ADR incidence varied significantly, particularly in dyspnea. The study highlighted significant CYP2C19 allele distribution differences between Hmong and Dong patients post-PCI in Qiandongnan. Patients with slow metabolic profiles demonstrated higher MACE incidence with conventional clopidogrel dosage, whereas CYP2C19-guided therapy reduced MACE without increasing bleeding risk. These findings supported clinical individualized clopidogrel administration in post-PCI patients in the Qiandongnan region, contributing to rational clopidogrel use.

The Impact of CYP 2C9 rs1799853 and rs1057910 Polymorphism on Plasma Losartan Metabolic Ratio in a Sample of Iraqi Hypertensive Patients

Background: The challenge associated with interindividual diversity in CYP2C9 enzyme activity is primarily related to genetic variations among individuals. Polymorphisms in the CYP2C9 gene can lead to different enzyme activity, affecting how individuals metabolize drugs. The understanding of interindividual diversity in CYP2C9 enzyme activity has implications for personalized medicine. Objective: To examine the impact of CYP2C9 gene polymorphisms (rs1799853 and rs1057910) on the losartan metabolism in Iraqi hypertensive patients. Methods: This prospective interventional study was conducted on a sample of hypertension patients from Babylon governorate, Iraq. All patients received 100 mg of losartan once daily. After 4 weeks, blood samples were obtained for genetic analysis and measuring losartan and its carboxylic acid (LCA) metabolite levels. The plasma losartan-to-LCA ratio is used as an indirect determinant of CYP2C9 activity within CYP2C9 SNP genotypes. Results: Two major allelic polymorphisms, CYP2C9 rs1799853 (T allele 15.5%) on exon 3 and rs1057910 (C allele 8.5%) on exon 7, have been identified among the patients. Plasma losartan/E3174 metabolic ratio was significantly higher in patients with a CT genotype of rs1799853 SNP (1.65) than in patients with a CC wild-type genotype (1.03). The losartan/E3174 metabolic ratio in heterozygous mutant AC genotypes of rs1057910 (1.18) was also higher than in those with wild-type AA genotypes (1.15); however, these differences are not statistically significant. Conclusions: The rs1799853 SNP variant, but not the rs1057910 SNP variant, significantly impacts CYP2C9 metabolic activity. The plasma losartan/E3174 metabolic ratio appears to be a practical and reliable measure for CYP2C9 activity.

Clinical analysis of dual enhanced antiplatelet therapy after cerebrovascular intervention for reducing the risk of cerebral infarction recurrence

To investigate the clinical assessment of dual-enhanced antiplatelet therapy after cerebrovascular intervention to reduce the risk of cerebral infarction recurrence, and to provide a reference for the prevention and treatment of cerebral infarction recurrence risk. 202 patients with cerebral infarction who underwent cerebrovascular intervention in Tianjin Fifth Central Hospital from January 2018 to October 2022 were selected as study subjects. The patients were divided into a treatment group (n=104) based on randomized controlled single-blind method with 61 males and 43 females with a mean age of (62.33±2.57) years old and a control group (n=98) with 56 males and 42 females with a mean age of (62.49±2.36) years old. The control group was given aspirin mono-antiplatelet therapy, and the treatment group was given clopidogrel doublet augmented antiplatelet therapy on the basis of the control group, and both groups continued the treatment for 2 months. Platelet counts, coagulation indexes and inflammatory factors were compared between the two groups before and after treatment, and the America National Institutes of Health Stroke Scale (NIHSS) score was used to assess the neurological functions of the two groups before and after treatment, and the recurrence of cerebral infarction in the two groups was counted within 6 months after treatment. In addition, the patients in the treatment group were divided into the cerebral infarction recurrence group and the cerebral infarction non-recurrence group according to whether they had cerebral infarction recurrence within 6 months after treatment, and the clinical data of the patients in the treatment group were collected to analyze the influencing factors of the dual-enhancement antiplatelet therapy for the recurrence of cerebral infarction in patients with cerebral infarction after cerebral vascular intervention by multifactorial logistic regression. The results showed that after treatment, patients in the treatment group had an international normalized ratio (INR) of (1.76±0.38), a platelet activation rate of (39.52±4.79)%, a platelet aggregation rate of (48.54±5.21)%, a tumor necrosis factor-alpha (TNF-alpha) of (28.37±4.47)ng/L, an interleukin 6 (IL-6) of (24.77±3.52)ng/L, a high-sensitivity C-reactive protein (hs-CRP) of (7.39±1.53)mg/L and an NIHSS score of (6.11±1.39) were lower than those of the control group (2.32±0.41), (44.81±6.37)%, (51.39±5.58)%, (39.66±4.51) ng/L, (29.25±4.04) ng/L, (9.03±1.78) mg/L and (9.93±1.46) points (all P<0.05). At 6-month follow-up of all patients, cerebral infarction recurred in 16 (15.38%) patients in the treatment group and in 33 (33.67%) patients in the control group (χ2=9.185, P<0.05). Kaplan-Meier results showed a statistically significant difference in the rate of recurrence without cerebral infarction in the treatment group compared with the control group(LogRank χ2=4.595,P<0.05). Logistic regression analysis showed that smoking history, cervical vascular plaque, post-treatment NIHSS score, post-treatment stenosis score, post-treatment INR, post-treatment hs-CRP and CYP2C19 gene polymorphism were independent influences on the recurrence of cerebral infarction in cerebral infarction patients with cerebral vascular interventions followed by doublet augmentation of antiplatelet therapy (all P<0.05). In conclusion, dual-enhanced antiplatelet therapy may be an effective measure to reduce the risk of cerebral infarction recurrence after cerebrovascular intervention in patients with cerebral infarction, but it is still influenced by more factors.

The Influence of Genetic Polymorphisms on Warfarin Dosage Requirements in Cardiac Valve Surgery Patients

Aim: Warfarin, a widely prescribed anticoagulant, exhibits considerable variability in patient response, making its clinical use challenging due to a narrow therapeutic window. This study aimed to evaluate the prevalence of CYP2C9 and VKORC1 gene polymorphisms in a cohort of 87 Turkish patients who underwent cardiac valve surgery and received warfarin therapy, as well as to assess their impact on warfarin dosage requirements. Methods: The frequencies of CYP2C9 and VKORC1 polymorphisms were analyzed, and patients were stratified based on the presence or absence of mutations affecting warfarin dosing. Results: Revealed that patients carrying at least one CYP2C9 or VKORC1 polymorphism required a significantly lower weekly warfarin dose to achieve the optimal international normalized ratio (INR). Conclusion: This study highlights the critical role of genetic factors in determining warfarin dosage and supports the integration of pharmacogenetic testing into clinical practice to personalize warfarin therapy. Such an approach has the potential to enhance treatment outcomes and minimize the risk of adverse events. Further research involving larger sample sizes and diverse patient populations is warranted to validate these findings and refine the current understanding of the genetic determinants of warfarin dosing.

Analysis of the effect of CYP2C19 gene properties on the anti-platelet aggregation of clopidogrel after carotid artery stenting under network pharmacology

Antiplatelet therapy is an important factor influencing the postterm patency rate of carotid artery stenting (CAS). Clopidogrel is a platelet aggregation inhibitor mediated by the adenosine diphosphate receptor and is affected by CYP2C19 gene polymorphisms in vivo. When the CYP2C19 gene has a nonfunctional mutation, the activity of the encoded enzyme will be weakened or lost, which directly affects the metabolism of clopidogrel and ultimately weakens its antiplatelet aggregation ability. Therefore, based on network pharmacology, analyzing the influence of CYP2C19 gene polymorphisms on the antiplatelet therapeutic effect of clopidogrel after CAS is highly important for the formulation of individualized clinical drug regimens. The effect of the CYP2C19 gene polymorphism on the antiplatelet aggregation of clopidogrel after CAS was analyzed based on network pharmacology. A total of 100 patients with ischemic cerebrovascular disease who were confirmed by the neurology department and required CAS treatment were studied. CYP2C19 genotyping was performed on all patients via a gene chip. All patients were classified into the wild-type (WT) group (*1/*1), heterozygous mutation (HTM) group (CYP2C19*1/*2, CYP2C19*1/*3), and homozygous mutation (HMM) group (CYP2C19*2/*2, CYP2C19*2/*3, and CYP2C19*3/*3). High-performance liquid chromatography (HPLC) with tandem mass spectrometry (MS/MS) was used to detect the blood concentration of clopidogrel and the plasma clopidogrel clearance (CL) rate in different groups of patients before and after clopidogrel treatment. The platelet aggregation rate of patients with different genotypes was measured by turbidimetry. The incidences of clopidogrel resistance (CR) and stent thrombosis in different groups after three months of treatment were analyzed. The results showed that among the different CYP2C19 genotypes, patients from the HTM group accounted for the most patients, while patients from the HTM group accounted for the least patients. Similarly, the clopidogrel CL of patients in the HMM group was lower than that of patients in the WT group and HTM group (P < 0.01). The platelet inhibition rate of patients in the HMM group was evidently inferior to that of patients in the WT group and HTM group (P < 0.01). The incidence of CR and stent thrombosis in the WT group was notably lower than that in the HTM and HMM groups (P < 0.01). These results indicate that the CYP2C19 gene can affect CR occurrence and stent thrombosis after CAS by influencing clopidogrel metabolism and platelet count.

Frequency of CYP2C19, P2RY12, ITGB3, ITGA2, and eNOS3 gene polymorphism in patients with myocardial infarction

The aim of the study was to assess the distribution of polymorphic variants G681A (*2) of the CYP2C19 gene, H1/H2 of the P2RY12 gene, T1565C of the ITGB3 gene, C807T of the ITGA2 gene, and T786C of the eNOS3 gene in the population of the Grodno region, and to study their associations with myocardial infarction (MI). The study of the population consists of 493 people, including 400 patients with MI aged 31 to 74 years and 93 people of the control group aged 32 to 60 years. Research data (clinical and genotyping performed by polymerase chain reaction) were analyzed using STATISTICA 10.0 software. The prevalence of carriage of genotypes associated with high residual platelet reactivity and variability in response to dual antiplatelet therapy among patients with MI was 25.2 % for the G681A polymorphic locus of the CYP2C19 gene (GA + AA), and for the H1/H2 polymorphic locus of the P2RY12 gene (H1/H2 + H2/H2) – 40.0 %, for the C807T polymorphic locus of the ITGA2 gene (CT + TT) – 65.8, for the T1565C polymorphic locus of the ITGB3 gene (TC + CC) – 25.5, for the polymorphic locus T786C of the eNOS gene (TC + CC) – 69.2 %. Among the individuals of the control group, the frequency of occurrence of these genotypes was 18.3, 46.2, 60.2, 37.6, 48.4 %, respectively. In patients with MI, compared to the control group, the TT genotype of the eNOS gene was less common (χ2 = 13.6, p = 0.0002), the CC genotype of the eNOS gene (χ2 = 5.4, p = 0.02) and the allele 786C of the eNOS gene (χ2 = 15.1, p = 0.0001) were more often detected. The carriage of the 786C allele of the eNOS gene increased the risk of MI in the studied population (OR = 2.0, 95 % CI: 1.41‒2.82, p = 0.0001). Gender differences were not found in the distribution of genotypes and alleles within the studied groups. There were no differences in carriage by the number of combinations of minor alleles between the control group and patients with MI. The most common combinations of minor alleles in both groups were comparable.

Effect on emergence from anesthesia following induction with diazepam and its association with CYP2C9, CYP2C19 and CYP3A4 gene polymorphisms

Introduction &amp; Objectives: Benzodiazepines are commonly used as adjuvants to IV anesthetic agents. Diazepam dosage varies widely depending on the desired endpoints. The rationale behind such inter-individual variability in drug responses has been attributed to genetically determined alterations in the enzyme activities. We assessed the emergence time in patients after induction of anesthesia with two different doses of diazepam and evaluated if any correlation exists between the emergence time and genetic polymorphism in drug metabolizers CYP2C19, CYP2C9, and CYP3A4 genes. Methodology: The study was conducted on randomly selected adult patients scheduled for elective surgery between 40-60 y of age with predefined inclusion and exclusion criteria. The patients were distributed into 2 groups, with group 1 receiving 0.2 mg/kg and group 2 given 0.3 mg/kg diazepam. Wake-up time after surgery was determined after a standardized verbal command played by a tape-recorder. Three ml blood in Ethylenediaminetetraacetic acid (EDTA) was collected before administering anesthesia. Results: Wake-up time between 8-18 min did not vary between the two groups. Comparatively persons having 2C19 2 took longer time to wake-up but this association was not statistically significant. However, CYP2C9 2 and 2 C9 3 and CYP3A4 genotypes had no influence on wake-up time. Conclusion: The pilot study suggests the emergence time from diazepam is longer in patients having 2C19 2 which confers slow-metabolizer phenotype. However, this study needs to be replicated in larger sample size to arrive at definitive conclusions before clinical applications. Abbreviations: BDZ- benzodiazepine; EDTA- Ethylenediaminetetraacetic acid; GA-General Anesthesia Key words: Diazepam; Emergence; Gene Polymorphism; Pharmacogenetics Citation: Mittal T, Badhe VK, Badhe DSD, Ahluwalia P, Mitta Bl, Mittal R. Effect on emergence from anesthesia following induction with diazepam and its association with CYP2C9, CYP2C19 and CYP3A4 gene polymorphisms. Anaesth. pain intensive care 2024;28(1):126-138. DOI: 10.35975/apic.v28i1.2380 Received: July 20, 2023; Reviewed: December 07, 2023; Accepted: December 07, 2023

Defining light transmission aggregometry cutoff values for clopidogrel and aspirin resistance in flow diversion treatment of intracranial aneurysms.

Concern about thromboembolic events after flow diversion (FD) warrants dual antiplatelet therapy for 3 to 6 months. Platelet function tests are routinely performed prior to the procedure to detect clopidogrel responsiveness, as resistance is associated with CYP2C19 gene polymorphisms. This study aimed to identify optimal cutoff values in light transmission aggregometry (LTA) for clopidogrel and aspirin as predictive indicators of thromboembolic complications. The authors conducted a retrospective analysis of aneurysms treated with FD between 2013 and 2023 at a single academic institution. Patients with LTA data for adenosine diphosphate (ADP) and arachidonic acid (ARA) were included, excluding those with aborted procedures. Receiver operating characteristic curves were plotted for ADP and ARA assays to determine optimal cutoff values. A total of 442 patients harboring 552 aneurysms treated in 485 procedures were selected for this analysis. Complete and near-complete aneurysm occlusion on the last radiological follow-up was achieved in 81.8% of aneurysms in a median last imaging follow-up of 13.9 months. A good functional outcome (modified Rankin Scale score ≤ 2) was achieved in 96.3% of patients on the last follow-up. Thromboembolic complications occurred in 4.9% of procedures, and intracranial hemorrhagic complications in 1.9%. For the ADP assay, a value ≥ 40% reached a sensitivity of 82.1% and a specificity of 42.9% with a positive likelihood ratio (LR) of 1.50. For the ARA assay, a value ≥ 13.5% reached a sensitivity of 82.1% and a specificity of 45.6% with a positive LR of 1.51. This study analyzed the largest FD-treated cohort in which optimal LTA platelet function thresholds for clopidogrel were evaluated and is the first to assess LTA values for aspirin. The authors found that values ≥ 40% for clopidogrel and ≥ 13.5% for aspirin were optimal for predicting thromboembolic complications after FD in treating aneurysms.

The Influence of CYP2C19 Gene Polymorphism on Selective Serotonin Reuptake Inhibitors In Patients with Major Depressive Disorder: A Pharmacogenetic Prospecting Approach

Major Depressive Disorder (MDD) is a chronic disorder characterized by at least a two-week-long major depressive episode. Selective Serotonin Reuptake Inhibitors (SSRIs) remain the primary prescribed antidepressants to treat MDD. However, SSRIs themselves are found to be ineffective in some individuals or may even lead to adverse side effects. These variable responses have been linked to the drug being metabolized by CYP2C19, which exhibited various polymorphisms. Understanding how gene polymorphism affects drug metabolism is essential since these insights can revolutionize clinical practice, allowing for more precise and personalized treatment approaches that optimize efficacy while minimizing side effects. This issue is particularly pertinent in Indonesia, where research in this area lags behind the pressing need for such studies. In this review, the impact of CYP2C19 polymorphism on the effectiveness of SSRI class drugs, namely citalopram, escitalopram, and sertraline, are explored. Nine relevant articles related to the topic have been studied in Japan, China, Turkey, Russia, Scandinavia, and Australia. The results concluded that CYP2C19 polymorphism can influence the metabolism of SSRIs (citalopram, escitalopram, and sertraline) due to its variability in enzyme activities, which includes both loss-of-function (*2, *3) and gain-of-function (*17) polymorphisms. Consequently, these genetic variations can lead to significant changes in drug efficacy and safety changes within individual patients. This review sheds light on the importance of considering genetic factors when prescribing SSRIs for MDD in the future treatment strategies.

Genetic variability in stroke patients: CYP2C19 polymorphisms unraveled

ObjectiveTo study the distribution characteristics of CYP2C19 polymorphisms in patients suffering from stroke in Han Chinese patients.MethodPCR and DNA microarray chip technology were used to detect the CYP2C19 genotype of 549 patients with stroke, and the genotype, allele frequency and metabolic type of patients with different sexes, ages and types of infarctions and the independent risk factors for clopidogrel resistance were analyzed.ResultsSix genotypes were detected in these 549 patients. A total of 233 (42.44%) patients had the heterozygous allele *1/*2, which was the most prevalent, followed by the homozygous wild-type allele *1/*1 (191, 34.79%). A total of 30 (5.46%) patients possessed the heterozygous allele *1/*3, and 65 (11.84%) patients had the homozygous mutant allele *2/*2. Twenty-nine (5.28%) patients had the compound heterozygous mutant allele *2/*3, and only 1 patient had the homozygous mutant allele *3/*3. The distribution of genotypes, alleles, and metabolic types did not change significantly (P > 0.05) by sex, age, or type of stroke. In addition, no independent risk factors for clopidogrel resistance were found in this analysis.ConclusionThe distribution of CYP2C19 genotypes, allele frequencies, and metabolic types in patients with stroke in Han Chinese patients were not correlated with sex, age, or infarction type. The possibilities of hyperglycemia, hypercholesterolemia, hypertriglyceridemia, hypo-HDL-cholesterolemia, hyper-LDL-cholesterolemia and high blood pressure were not statistically associated with CYP2C19 genotypes. CYP2C19 gene polymorphism detection is recommended for patients who are available, and during treatment, the CYP2C19 genotype can be used to guide personalized precise medication use in patients with stroke.

Distribution of CYP2D6 and CYP2C19 gene polymorphisms in Han and Uygur populations with breast cancer in Xinjiang, China.

The aim of this study was to investigate the frequency distribution of the cytochrome P450 (CYP450) enzymes, CYP2D6 and CYP2C19, and the form of tamoxifen metabolisation in premenopausal patients with breast cancer in the Han and Uygur ethnic groups of Xinjiang to guide rational clinical drug use. A total of 125 Han patients and 121 Uygur patients with premenopausal hormone-receptor-positive breast cancer treated at the Xinjiang Uygur Autonomous Region Cancer Hospital between 1 June 2011 and 1 December 2013 were selected. The common mutation sites in CYP450 were analysed using TaqMan® minor groove binder technology. Genetic testing was performed to determine other metabolic types of tamoxifen, and the genotypes and metabolic types were compared using a Chi-squared test. Between the Han and Uygur groups, there were significant differences in the frequencies of the CYP2D6 (*10/*10) and CYP2C19 (*1/*1) genotypes, with P-values of 0.002 and 0.015, respectively. Genotypes of CYP2D6 (*1/*1), CYP2D6 (*1/*5), CYP2D6 (*5/*5), CYP2D6 (*5/*10) and CYP2C19 (*3/*3) were expressed in the two patient groups, and the difference was not statistically significant (P > 0.05). In the Han patients, the proportions of extensive, intermediate and poor metabolisers of tamoxifen were 72, 24 and 4%, respectively, whereas those in the Uygur patients were 76.9, 17.4 and 5.7%, respectively, with no significant difference (P > 0.05). In conclusion, There were partial differences in the CYP2D6 and CYP2C19 gene polymorphisms of CYP450 between the Han and Uygur patients with premenopausal breast cancer, but there was no significant difference between the CYP2D6 and CYP2C19 phenotypes. Further research is needed to determine the relationship between the enzyme genetic differences of CYP450 and the pharmacokinetics and efficacy of tamoxifen. Although there were some differences in genotypes, these did not result in differences in the predicted tamoxifen metabolisation phenotype between the Han and Uygur patients with breast cancer. Therefore, the doses should be adjusted according to the individual genotype data.

CYP2C19 gene variants and major depressive disorder: integrative review

Major depressive disorder (MDD) is a multifactorial condition common in the general population, treated with different antidepressants. Several genes are involved in the metabolism of these antidepressants, including CYP2C19. Consequently, functional polymorphisms in these genes affect these drugs' metabolism. Through an integrative review, this research aimed to verify the CYP2C19 gene polymorphisms' influence on antidepressant metabolism, evaluate their frequency in patients affected by MDD, verify clinical and demographic characteristics of studied populations, and identify possible associations of this gene with MDD. The database used to search for articles was Biblioteca Virtual em Saúde - BVS, and four articles were selected. Polymorphisms in the CYP2C19 gene may contribute to the metabolism of some antidepressants, such as citalopram, but not others, such as venlafaxine and sertraline. Interestingly, the drug sertraline can influence the levels of lipid profile parameters. In addition, some polymorphisms may be relatively frequent depending on the populations, such as Asians. No CYP2C19 polymorphisms associated with MDD development were observed.

Personalized approach to outpatient management of patients taking tamoxifen by gynecologists

BACKGROUND: 30% of women with luminal breast cancer receiving adjuvant tamoxifen experience disease recurrence within 15 years. This demonstrates the wide variability in clinical response to tamoxifen. Both nongenetic (age, gender, body mass index, duration of drug use) and genetic factors have been described to influence the high variability of response to tamoxifen. Differences in the genes encoding the enzymes CYP2D6, CYP2C, and CYP3A (CYP2D6*4, CYP3A5*3, CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP2C19*3) and the ABCB1 gene (C3435T) may also be the main factors of susceptibility to the occurrence of undesirable effects when taking tamoxifen, which in turn may lead to decreased patient adherence to therapy.&#x0D; AIM: The aim of this study was to create a concept and an algorithm for a personalized approach to outpatient management of patients taking tamoxifen by a gynecologist in connection with the carriage of polymorphisms of cytochrome P450 and drug transporter genes.&#x0D; MATERIALS AND METHODS: In 2017–2018, the outpatient records of 230 patients with breast cancer were analyzed retrospectively. A single-stage pharmacogenetic study of 120 women with stage I–III luminal breast cancer taking tamoxifen was conducted prospectively for the presence of cytochrome P450 gene polymorphisms using the polymerase chain reaction method and assessing associations with adverse drug reactions, and 54 patients were interviewed after five-year follow-up to assess adherence and satisfaction with medical supervision.&#x0D; RESULTS: The likelihood of developing endometrial hyperplasia has been shown to increase while taking tamoxifen with increasing average age, body mass index, duration of tamoxifen use, and postmenopause. Significant associations have been identified between the carriage of the CYP2D6, CYP2C9, CYP2C19, CYP3A5, and ABCB1 gene polymorphisms and the development of adverse drug reactions. Predictive models have been developed to determine the risk of adverse drug reactions. All studied adverse drug reactions associated with various genetic polymorphisms predominated in the group of patients who stopped taking tamoxifen due to poor intolerance. Gynecologists regularly observed 57.4% of patients. Moreover, the higher the adherence to therapy was, the higher was the regularity of observation by a gynecologist.&#x0D; CONCLUSIONS: A plan for outpatient management of patients receiving adjuvant endocrine therapy with tamoxifen by a gynecologist has been developed.

Effects of the EM CYP2C19 type and MDR1 3435CC gene on Helicobacter pylori eradication rate in patients with duodenal ulcer by the four-drug regimen of rabeprazole, bismuth, tetracycline, and tinidazole

Background: The MDR1 genotype and the CYP2C19 phenotype determine how much PPI is absorbed from the gut and how much is processed in the liver. Objective: To assess the impact of CYP2C19 and MDR1 C3435T gene polymorphisms on the efficiency of H. pylori eradication treatment with a 4-drug regimen of rabeprazole, bismuth, tetracycline, and tinidazole (RBTT) in patients with duodenal ulcers. Methods: The study was conducted at Can Tho University of Medicine and Pharmacy. Gene polymorphisms for CYP2C19 and MDR1 C3435T were detected through a blood test. The RBTT 4-drug regimen was used to eradicate H. pylori. Results: The success rate of the RBTT regimen for eradicating H. pylori in female patients with the CYP2C19 EM phenotype + MDR1 3435CC genotype was 20.0% lower than the rate of 91.7% for the group without both phenotype and genotype (p = 0.01, OR = 0.02, 95%CI: 0.00–0.45). Conclusion: Compared to the group lacking both phenotypes and genotypes, female patients with the CYP2C19 EM phenotype + MDR1 3435CC genotype had a lower rate of H. pylori eradication by RBTT regimen.

Aiming for precision: CYP2C19 gene polymorphism and clopidogrel resistance in patients with peripheral artery disease

Aiming for precision: CYP2C19 gene polymorphism and clopidogrel resistance in patients with peripheral artery disease

Physiologically Based Pharmacokinetic Modeling to Unravel the Drug-gene Interactions of Venlafaxine: Based on Activity Score-dependent Metabolism by CYP2D6 and CYP2C19 Polymorphisms.

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. 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). The parent-metabolite PBPK models for VEN and ODV were developed using PK-Sim® and MoBi®. Leveraging prior research, derived and implemented CYP2D6 and CYP2C19 activity score (AS)-dependent metabolism to simulate exposure in the drug-gene interactions (DGIs) scenarios. The model's performance was evaluated by comparing predicted and observed values of plasma concentration-time (PCT) curves and PK parameters values. In the base models, 91.1%, 94.8%, and 94.6% of the predicted plasma concentrations for VEN, ODV, and VEN + ODV, respectively, fell within a twofold error range of the corresponding observed concentrations. For DGI scenarios, these values were 81.4% and 85% for VEN and ODV, respectively. Comparing CYP2D6 AS = 2 (normal metabolizers, NM) populations to AS = 0 (poor metabolizers, PM), 0.25, 0.5, 0.75, 1.0 (intermediate metabolizers, IM), 1.25, 1.5 (NM), and 3.0 (ultrarapid metabolizers, UM) populations in CYP2C19 AS = 2.0 group, the predicted DGI AUC0-96h ratios for VEN were 3.65, 3.09, 2.60, 2.18, 1.84, 1.56, 1.34, 0.61, and for ODV, they were 0.17, 0.35, 0.51, 0.64, 0.75, 0.83, 0.90, 1.11, and the results were similar in other CYP2C19 groups. It should be noted that PK differences in CYP2C19 phenotypes were not similar across different CYP2D6 groups. In clinical practice, the impact of genotyping on the in vivo disposition process of VEN should be considered to ensure the safety and efficacy of treatment.

Factors Influencing Plasma Concentrations of Valproic Acid in Pediatric Patients With Epilepsy and the Clinical Significance of CYP2C9 Genotypes in Personalized Valproic Acid Therapy.

The aim of this study was to investigate the factors affecting plasma valproic acid (VPA) concentration in pediatric patients with epilepsy and the clinical significance of CYP2C9 gene polymorphisms in personalized dosing using therapeutic drug monitoring and pharmacogenetic testing. The medical records of children with epilepsy who underwent therapeutic drug monitoring at our institution between July 2022 and July 2023 and met the inclusion criteria were reviewed. Statistical analysis was performed to determine whether age, sex, blood ammonia, liver function, kidney function, and other characteristics affected the concentration-to-dose ratio of VPA (CDRV) in these patients. To investigate the effect of CYP2C9 polymorphisms on CDRV, DNA samples were collected from patients and the CYP2C9 genotypes were identified using real-time quantitative PCR. The mean age of 208 pediatric patients with epilepsy was 5.50 ± 3.50 years. Among these patients, 182 had the CYP2C9 *1/*1 genotype, with a mean CDRV (mcg.kg/mL.mg) of 2.64 ± 1.46, 24 had the CYP2C9 *1/*3 genotype, with a mean CDRV of 3.28 ± 1.74, and 2 had the CYP2C9 *3/*3 genotype, with a mean CDRV of 6.46 ± 3.33. There were statistical differences among these 3 genotypes ( P < 0.05). The CDRV in these patients were significantly influenced by age, aspartate aminotransferase, total bilirubin, direct bilirubin, globulin, albumin/globulin ratio, prealbumin, creatinine, and CYP2C9 polymorphisms. In addition, multivariate linear regression analysis identified total bilirubin, direct bilirubin, and CYP2C9 polymorphisms as independent risk factors for high CDRV. Liver problems and mutations in the CYP2C9 gene increase VPA levels. This underscores the importance of considering these factors when prescribing VPA to children with epilepsy, thereby enhancing the safety and efficacy of the therapy.