Influence of CYP2C19*2 gene variant on therapeutic response during clopidogrel treatment in patients with carotid artery stenosis

Uvod: I pored dokazanog kliničkog efekta oralne antiagregacijske terapije, značajan broj pacijenata nema adekvatan odgovor na primenjeni klopidogrel. Cilj naše studije je bio da se utvrdi uticaj prisutne CYP2C19*2 varijante gena na terapijski odgovor u toku primene klopidogrela kod pacijenata sa stenozom karotidne arterije. Metode: U jednogodišnju prospektivnu studiju uključeno je 112 pacijenata sa stenozom karotidne arterije kod kojih je izvršena endarterektomija. Posle operativnog zahvata, pacijenti su primali 75 mg dnevno klopidogrela u trajanju od najmanje mesec dana. Svi ispitanici su praćeni od momenta prijema. Za CYP2C19 genotipizaciju korišćen je TaqMan test. Uticaj CYP2C19*2 alela na trombocitnu reaktivnost ispitivan je primenom multiple-electrode aggregometry (MEA). Rezultati: Rezultati genotipizacije su pokazali da su 82 (73,2%) ispitanika homozigoti za wild-type, 29 (25,9%) heterozigoti za CYP2C19*2 alel, dok je 1 (0,9%) bio homozigot za CYP2C19*2. Nakon 24 sata, u grupi sa wild-type genotipom 29,3% ispitanika dali su odgovor na klopidogrel, a u grupi sa CYP2C19*2 varijantom gena 10% ispitanika. U grupi sa wild-type genotipom, 74,4% ispitanika su imali terapijski odgovor nakon 7 dana, odnosno 82,9% nakon 30 dana od primene klopidogrela. U grupi sa CYP2C19*2 alelom broj ispitanika sa terapijskim odgovorom raste do 46,7% nakon 7 dana, odnosno do 53,3% nakon 30 dana od primene klopidogrela. Rizik za slab odgovor je veći kod nosilaca CYP2C19*2 alela u odnosu na nenosioce (wild-type) (OR 4,250, 95% CI 1 .695 -10.658 , P lt 0,01). Zaključak: CYP2C19*2 varijanta gena značajno utiče na terapijski odgovor u toku primene klopidogrela kod bolesnika sa stenozom karotidne arterije kod kojih je izvršena endarterektomija.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 undergoing endarterectomy were included in this one-year prospective study. All of them received clopidogrel (75 mg daily) for at least 30 days after the intervention. They were followed from the moment of hospital admission. CYP2C19*2 genotyping was performed by TaqMan Assay. The influence of c Yp 2C 19*2 variant allele on clopidogrel platelet reactivity was determined using multiple-electrode aggregometry (MEA). Results: Genotyping results showed that 82 (73.2% ) patients were homozygous for wild type, 29 (25.9%) were heterozygous for the CYP2C19*2 allele and 1 (0.9%) was CYP2C19*2 homozygous. After 24 hours, among those with the wild type 29.3% were clopidogrel responders, and in those with the CYP2C19*2 alleles 10%. In the wild type group, 74.4% were clopidogrel responders after 7 days of taking the drug; 82.9% after 30 days of clopidogrel introduction, respectively. In patients with the CYP2C19*2 alleles the number of responders increased up to 46.7% after 7 days; 53.3% after 30 days of taking the drug, respectively. The risk for being a low-responder is higher for the patients heterozygous for the c Yp 2C 19*2 allele vs. wildtype (OR 4.250, 95% CI 1.695 -10.658 , P lt 0.01). Conclusions: The CYP2C19*2 loss-of-function variant allele has significant influence on clopidogrel response in patients with carotid artery stenosis undergoing endarterectomy

Analysis of the association of the CYP2C19 variants with the effects of clopidogrel therapy in patients underwent to carotid endarterectomy

Introduction. Despite proven clinical effect of clopidogrel, a considerable number of patients do not have an adequate response to this type of medication. Problems during therapy occur in the form of resistance, which is present in 11% of patients or bleeding that occurs in about 9% of patients. Pharmacogenomics studies demonstrated that variants of the CYP2C19 gene significantly influence the interindividual heterogenity of the clopidogrel response. The American Heart Association, US Food and Drug Administration and the European Medicines Agency, cite the CYP2C19 gene as a significant factor which influences patients response to clopidogrel. Further, it has been shown that the contribution of genetic and non-genetic factors affecting clopidogrel therapy may vary between patients from different populations, which justifies conducting population-specific studies. The aim. The aim of our study was to examine the significance of the CYP2C19*2 and the CYP2C19*17 variants in the individual response to clopidogrel, in Serbian patients. Methods. The study involved 108 patients with carotid artery stenosis who underwent endarterectomy and received clopidogrel for at least 30 days after the intervention. Also, 120 patients with myocardial infarction receiving clopidogrel after PCI (percutaneous coronary intervention) were included. Commercial tests were used for standard laboratory testing. Allelic discrimination was performed after Sanger sequencing. Results were analysed using statistical tests. Results. In patients undergoing endarterectomy CYP2C19*2 carriers had a higher risk for being clopidogrel low-responder in comparison with non-carriers (1.250, 95% CI 1.695–1.658, P<0.01). In the group of patients undergoing PCI, risk for reinfarction in patients who were carriers of CYP2C19*2 was higher compared to patients with wild type genotype (OR 5.355, 95% CI 0.955-31.08; P=0.038). Variant CYP2C19*17 showed no association with variations in response to clopidogrel therapy. Conclusion. The CYP2C19*2 variant shows significant association with a poor response to clopidogrel and it should be considered when planning therapy.XXIII Congress of the Cardiology society of Serbia, October 21-23, 2021, Belgrade, Serbia

Influence of Cyp2c19∗2 Gene Variant on Therapeutic Response during Clopidogrel Treatment in Patients with Carotid Artery Stenosis

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 undergoing endarterectomy were included in this one-year prospective study. All of them received clopidogrel (75 mg daily) for at least 30 days after the intervention. They were followed from the moment of hospital admission. CYP2C19*2 genotyping was performed by TaqMan Assay. The influence of CYP2C19*2 variant allele on clopidogrel platelet reactivity was determined using multiple-electrode aggregometry (MEA). Results: Genotyping results showed that 82 (73.2%) patients were homozygous for wild type, 29 (25.9%) were heterozygous for the CYP2C19*2 allele and 1 (0.9%) was CYP2C19*2 homozygous. After 24 hours, among those with the wild type 29.3% were clopidogrel responders, and in those with the CYP2C19*2 alleles 10%. In the wild type group, 74.4% were clopidogrel responders after 7 days of taking the drug; 82.9% after 30 days of clopidogrel introduction, respectively. In patients with the CYP2C19*2 alleles the number of responders increased up to 46.7% after 7 days; 53.3% after 30 days of taking the drug, respectively. The risk for being a low-responder is higher for the patients heterozygous for the CYP2C19*2 allele vs. wild type (OR 4.250, 95% CI 1.695-10.658, P lt 0.01). Conclusions: The CYP2C19*2 loss-of-function variant allele has significant influence on clopidogrel response in patients with carotid artery stenosis undergoing endarterectomy

Clopidogrel High On-Treatment Platelet Reactivity in Patients with Carotid Artery Stenosis Undergoing Endarterectomy. A Pilot Study

Objectives: A considerable number of patients do not achieve an adequate response to clopidogrel. Our study aimed to evaluate genetic and non-genetic factors as possible risks for clopidogrel high on-treatment platelet reactivity (HTPR) in patients (n=112) with carotid artery stenosis undergoing endarterectomy (CEA). Methods: Using multiple-electrode impedance aggregometry (MEA) the antiplatelet effectiveness of clopidogrel was measured after 24 h, 7 and 30 days of clopidogrel treatment, which was introduced after elective CEA at a dose of 75 mg daily, for at least 30 days. Results: HTPR was observed among 25% patients after clopidogrel therapy for 30 days. Further analysis showed that 53.3% of patients carrying the CYP2C19*2 gene variant had clopidogrel-HTPR, while in the wild type group there were 14.6% (p lt 0.001). Multivariate logistic regression analysis identified the CYP2C19*2 variant allele (OR 4.384; 95% CI 1.296-14.833, p=0.017) and high total cholesterol level (OR 2.090; 95% CI 1.263-3.459, p=0.004) as the only independent risk factors for clopidogrel-HTPR. Conclusion: The CYP2C19*2 gene variant and high total cholesterol level were major factors for clopidogrel-HTPR in patients with carotid artery stenosis undergoing CEA

Clopidogrel High On-Treatment Platelet Reactivity in Patients with Carotid Artery Stenosis Undergoing Endarterectomy. A Pilot Study

Objectives: A considerable number of patients do not achieve an adequate response to clopidogrel. Our study aimed to evaluate genetic and non-genetic factors as possible risks for clopidogrel high on-treatment platelet reactivity (HTPR) in patients (n=112) with carotid artery stenosis undergoing endarterectomy (CEA). Methods: Using multiple-electrode impedance aggregometry (MEA) the antiplatelet effectiveness of clopidogrel was measured after 24 h, 7 and 30 days of clopidogrel treatment, which was introduced after elective CEA at a dose of 75 mg daily, for at least 30 days. Results: HTPR was observed among 25% patients after clopidogrel therapy for 30 days. Further analysis showed that 53.3% of patients carrying the CYP2C19*2 gene variant had clopidogrel-HTPR, while in the wild type group there were 14.6% (p lt 0.001). Multivariate logistic regression analysis identified the CYP2C19*2 variant allele (OR 4.384; 95% CI 1.296-14.833, p=0.017) and high total cholesterol level (OR 2.090; 95% CI 1.263-3.459, p=0.004) as the only independent risk factors for clopidogrel-HTPR. Conclusion: The CYP2C19*2 gene variant and high total cholesterol level were major factors for clopidogrel-HTPR in patients with carotid artery stenosis undergoing CEA

Risk factors for clopidogrel high on-treatment platelet reactivity in patients with carotid artery stenosis undergoing endarterectomy

Objectives: A considerable number of patients do not achieve an adequate response to clopidogrel. Our study aimed to evaluate genetic and non-genetic factors as possible risks for clopidogrel high on-treatment platelet reactivity (HTPR) in patients (n=112) with carotid artery stenosis undergoing endarterectomy (CEA). Methods: Using multiple-electrode impedance aggregometry (MEA) the antiplatelet effectiveness of clopidogrel was measured after 24 h, 7 and 30 days of clopidogrel treatment, which was introduced after elective CEA at a dose of 75 mg daily, for at least 30 days. Results: HTPR was observed among 25% patients after clopidogrel therapy for 30 days. Further analysis showed that 53.3% of patients carrying the CYP2C19*2 gene variant had clopidogrel-HTPR, while in the wild type group there were 14.6% (p lt 0.001). Multivariate logistic regression analysis identified the CYP2C19*2 variant allele (OR 4.384; 95% CI 1.296-14.833, p=0.017) and high total cholesterol level (OR 2.090; 95% CI 1.263-3.459, p=0.004) as the only independent risk factors for clopidogrel-HTPR. Conclusion: The CYP2C19*2 gene variant and high total cholesterol level were major factors for clopidogrel-HTPR in patients with carotid artery stenosis undergoing CEA