Репозиторий Университета

© 2019, Springer Nature B.V. The objective of this study was to determine the impact of polymorphism of CYP3A subfamily isoenzymes (allelic variants of CYP3A4*22 and CYP3A5*3) on the efficacy clopidogrel in patients with an acute coronary syndrome (ACS), who have undergone percutaneous coronary intervention (PCI). Platelet activity was determined on a VerifyNow P2Y12 test system in 81 patients with ACS aged 37–91 who had PCI. The activity of CYP3A4/5 was expressed as the ratio of the concentrations of cortisol and 6β-hydroxycortisol was performed by using high performance liquid chromatography. Genotyping was performed by using real-time polymerase real-time chain reaction. The frequencies for the CYP3A5 gene, rs 776746, were identified as follows: 77 (95.1%)—CC, 4 (4.9%)—CT; the allele frequencies by loci for the CYP3A4, rs rs35599367, were as follows: 78 (96.3%)—GG, 3 (3.7%)—AG. There was no statistically significant genotype-dependent difference between the presence of a minor T and G alleles and the presence of clopidogrel resistance (OR 3.53; 95% CI 0.46–26.94; p = 0.233 and p = 0.443, respectively). The average level of the metabolic relationship (6β-hydroxycortisol/cortisol) between the clopidogrel-resistant group and the normal platelet reactivity group was not statistically significantly different: 3.3 ± 2.8 versus 3.2 ± 3.2; p = 0.947. So, the activity of CYP3A4/5 was not related to platelet aggregation rates in this model. Genotyping and phenotyping CYP3A4\CYP3A5 does not predict the antiplatelet effect of clopidogrel. More extensive research is required to establish their clinical relevance.

© 2018 2018 Walter de Gruyter GmbH, Berlin/Boston. The aim was to study seven polymorphic markers of genes encoding proteins involved in the absorption, metabolism and pharmacokinetics of clopidogrel among patients with an acute coronary syndrome (ACS), who have undergone percutaneous coronary intervention (PCI). Eighty-one ACS and PCI patients older than 18 years and treated with dual antiplatelet therapy were enrolled in the study. Platelet function testing and ABCB1, CYP2C19, CYP3A5 and CYP4F2 genotyping were performed. The predictive role of categorical variables, such as genotypes (carriers and non-carriers of polymorphism), on platelet reactivity (platelet reactivity units [PRU] platelet inhibition [PI]) was assessed by logistic regression (for categorical outcomes) and linear regression (for continuous outcomes) analysis. A p-value<0.05 was considered significant. The allele frequencies were estimated by gene counting, and Hardy-Weinberg equilibrium was tested using the chi-square test. Regarding clopidogrel response, 62 patients (76.5%) were clopidogrel responders and 19 were non-responders (23.5%). Mean PRU value and the percentage of platelet inhibition were 170.0±50.9 PRU and 28.6±19.9%, respectively. The effects of the CYP2C19∗2 polymorphisms on PRU (166.0±50.8 vs. 190.7±48.2, p<0.038) and PI (30.6±20.0 vs. 18.1±16.3, p<0.013) were observed, and the rates of high platelet reactivity (HPR) were lower in CYP2C19∗1/∗1 than those in CYP2C19∗1/∗2+CYP2C19∗2/∗2 (16.2% vs. 53.8% p<0.0067). In comparison, no significant difference in PRU value and PI was observed at <5 days between the rest of polymorphisms (p>0.05). Based on the logistic regression analysis, CYP2C19∗2 (OR: 4.365, CI: 1.25-17.67, p=0.022) was an independent predictor of HPR at <5 days, as was the stent diameter (OR: 0.219, CI: 0.002-0.229, p=0.049). The remaining polymorphisms had no influence. The reactivity of the on-clopidogrel platelet in the early phase of ACS is influenced primarily by the CYP2C19 polymorphisms. We believe that the findings of the present study could supply additional evidence regarding the clinical appropriateness of the CYP2C19 genetic testing for designing suitable antiplatelet therapy in the early phase of ACS.

© 2018 Walter de Gruyter GmbH, Berlin/Boston. The focus of the study is to determine the prevalence of CYP2C19 alleles, associated with the risk of changes in the pharmacological response to clopidogrel and proton pump inhibitors in patients with acute coronary syndrome (ACS) and gastric ulcer from Russian and Yakut ethnic groups. The research included 411 patients with ACS (143 Russians and 268 Yakuts) and 204 patients with histologically confirmed gastric ulcer (63 Russians and 141 Yakuts). Genotyping of 681G>A and 636G>A polymorphisms was performed by using polymerase real-time chain reaction. In both ethnic groups, Hardy-Weinberg equilibrium was followed in a distribution of alleles and genotypes in the population (p>0.05). The 681A allele frequency in the Yakut ethnic group was higher than in the Russian group: 17.53% vs. 8.39% (p=0.001). No statistically significant difference was found in the frequency of 636A in Yakuts and Russians with ACS: 3.92% vs. 3.50% (p=0.840). While comparing the frequency distribution of alleles 681A (13.49% vs. 14.54%, p=0.878) and 636A (7.94% vs. 7.80%, p=1) in patients with a gastric ulcer from Russian and Yakut ethnic groups, no significant difference was found in carrier frequency. The results of the present study may be helpful for developing guidelines for CYPC19 genotype-directed antiplatelet therapy for Yakut and Russian patients.

© 2018, Stolichnaya Izdatelskaya Kompaniya. The aim of the review is presenting the possibilities and perspectives of the third generation of thienopyridine P2Y12 receptor inhibitor prasugrel in the treatment of patients with acute coronary syndrome (ACS). The main pathogenetic stage of ACS is intracoronary thrombosis, which develops on the surface of a damaged atherosclerotic plaque. The use of acetylsalicylic acid with addition of the second antiplatelet agent, so-called dual antiplatelet therapy, is a standard component in the treatment of any type of ACS, regardless of reperfusion and the selected treatment strategy. Due to some limitations in the use of clopidogrel as the second component of dual antiplatelet therapy, the possibility of prasugrel or ticagrelor usage should be considered in patients with ACS with percutaneous coronary intervention (PCI). Prasugrel therapy is associated with better clinical outcomes as compared with clopidogrel therapy in moderate or high-risk patients who undergo PCI. Because of higher bleeding risk and the lack of clinical benefits in special subgroups of patients, prasugrel must not be used in patients with a stroke or transient ischemic attack in the past. If, after a thorough individual benefit-risk assessment a decision is in favor of prescribing prasugrel to the patient older than 75 years or with a small body weight the maintenance dose of prasugrel is to be reduced by half. Real clinical practice data has shown that with following these recommendations prasugrel demonstrates optimal efficacy, safety, and even more significant impact on the prognosis than this in clinical trials. Prasugrel is able to reduce significantly the incidence of cardiovascular events such as cardiovascular death, myocardial infarction and stroke in patients with ACS who undergo PCI.

© 2018, Silicea-Poligraf. All rights reserved. Aim. To compare antiplatelet activeness of the original clopidogrel and its generic, and to evaluate the routine practice of antiplatelet drugs intake by clinically stable patients aiming prevention of atherothrombosis. Material and methods. Total number of patients that have been taking clopidogrel: 186, of those at outpatient stage 54 on original clopidogrel, the rest 132 on generic. Adenosindiphosphate-induced activeness was measured in two groups (n=57) taking consequently Plavix and Clapitax before replacement of the drug and 14 days after. Results. At interchange of the drug in group 1 (Clapitax to Plavix) and group 2 (Plavix to Clapitax) the grade of achieved effect remained, and in group 2 it showed additional non-significant decrease. Adverse events related to antiplatelet therapy were not registered. At in-patient stage, 117 patients had an interchange of the drug (incl. several times) of original clopidogrel to its various generics (n=65), and vice versa (n=52), that was related to a range of routine reasons, of those patient and relatives preferences, specifics of drug supply in a clinic. Conclusion. The found equal residual reactivity of the platelets after Clapitax and Plavix intake in two groups witness on therapeutical equivalence of the drugs.