Enhanced active metabolite generation and platelet inhibition with prasugrel compared to clopidogrel regardless of genotype in thienopyridine metabolic pathways

2013 ◽  
Vol 110 (12) ◽  
pp. 1223-1231 ◽  
Author(s):  
Dominick J. Angiolillo ◽  
Jose L. Ferreiro ◽  
Joseph A. Jakubowski ◽  
Kenneth J. Winters ◽  
Mark B. Effron ◽  
...  
Keyword(s):  
Genetic Variants ◽  
Active Metabolite ◽  
Platelet Reactivity ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
Reactivity Index ◽  
Coronary Syndrome ◽  
Metabolite Generation ◽  
Artery Disease ◽  
The Impact

SummaryClopidogrel response varies according to the presence of genetic polymorphisms. The CYP2C19*2 allele has been associated with impaired response; conflicting results have been reported for CYP2C19*17, ABCB1, and PON1 genotypes. We assessed the impact of CYP2C19, PON1, and ABCB1 polymorphisms on clopidogrel and prasugrel pharmacodynamic (PD) and pharmacokinetic (PK) parameters. Aspirin-treated patients (N=194) with coronary artery disease from two independent, prospective, randomised, multi-centre studies comparing clopidogrel (75 mg) and prasugrel (10 mg) were genotyped and classified by predicted CYP2C19 metaboliser phenotype (ultra metabolisers [UM] = *17 carriers; extensive metabolisers [EM] = *1/1 homozygotes; reduced metabolisers [RM] = *2 carriers). ABCB1 T/T and C/T polymorphisms and PON1 A/A, A/G and G/G polymorphisms were also genotyped. PD parameters were assessed using VerifyNow® P2Y12 and vasodilator stimulated phosphoprotein (VASP) expressed as platelet reactivity index (PRI) after 14 days of maintenance dosing. Clopidogrel and prasugrel active metabolite (AM) exposure was calculated in a cohort of 96 patients. For clopidogrel, genetic variants in CYP2C19, but not ABCB1 or PON1, affected PK and PD. For prasugrel, none of the measured genetic variants affected PK or PD. Compared with clopidogrel, platelet inhibition with prasugrel was greater even in the CYP2C19 UM phenotype. Prasugrel generated more AM and achieved greater platelet inhibition than clopidogrel irrespective of CYP2C19, ABCB1, and PON1 polymorphisms. The lack of effect from genetic variants on prasugrel AM generation or antiplatelet activity is consistent with previous studies in healthy volunteers and is consistent with improved efficacy in acute coronary syndrome patients managed with percutaneous coronary intervention.

scholarly journals Validation of a New ELISA-Based Vasodilator-Associated Stimulated Phosphoprotein Phosphorylation Assay to Assess Platelet Reactivity Index in a Chinese Population

2017 ◽  
Vol 24 (3) ◽  
pp. 452-461 ◽  
Author(s):  
Peng Ding ◽  
Yujie Wei ◽  
Nana Chen ◽  
Huiliang Liu
Keyword(s):  
Acute Coronary Syndrome ◽  
Healthy Volunteers ◽  
Chinese Population ◽  
Platelet Reactivity ◽  
Adenosine Diphosphate ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
Reactivity Index ◽  
Enzyme Linked Immunosorbent Assay ◽  
Coronary Syndrome

The level of platelet reactivity during P2Y12-adenosine diphosphate receptor antagonist is associated with ischemic and bleeding risks following percutaneous coronary intervention in acute coronary syndrome. Determining platelet reactivity inhibition may be valuable for confirming effective platelet inhibition for individual patients and identifying patients at risk of bleeding. The enzyme-linked immunosorbent assay (ELISA)-based vasodilator-stimulated phosphoprotein (VASP) assay offers unique advantages over other methods and has not been used in the Chinese population. We enrolled 10 healthy volunteers and 54 patients with acute coronary syndrome. The volunteers received no treatment, and patients were administered a loading dose of clopidogrel or ticagrelor. The platelet reactivity index (PRI) was measured using flow cytometry (FC)-VASP and ELISA-VASP at baseline and 8-hour postloading dose. Blood samples of healthy volunteers and clopidogrel- or ticagrelor-treated patients were frozen and stored for 1, 2, and 4 weeks after initial activation. All frozen samples were tested using ELISA-VASP. The PRI assessed by FC-VASP and ELISA-VASP correlated well showing a high degree of consistency in identifying high or low on-treatment platelet reactivity. No significant time-dependent changes in PRI results were observed in frozen samples stored up to 4 weeks compared to nonfrozen samples. The PRI of ticagrelor-treated patients was lower than that of clopidogrel-treated patients. The ELISA-VASP effectively assesses the PRI, and results obtained from frozen specimens are unaffected by storage and shipment prior to assay. Ticagrelor was superior to clopidogrel in decreasing the PRI.

Early determination of clopidogrel responsiveness by platelet reactivity index identifies patients at risk for cardiovascular events after myocardial infarction

2011 ◽  
Vol 106 (07) ◽  
pp. 141-148 ◽  
Author(s):  
Andreas Schäfer ◽  
Ulrike Flierl ◽  
Jürgen Kössler ◽  
Nora Seydelmann ◽  
Anna Kobsar ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Platelet Reactivity ◽  
Density Lipoprotein ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
Systematic Evaluation ◽  
Reactivity Index ◽  
Operating Characteristics ◽  
Patients At Risk ◽  
Acute Mi

SummaryWhile acute myocardial infarction (MI) is associated with impaired clopidogrel responsiveness, systematic evaluation is lacking due to the inability of functional aggregation-based assays to analyse clopidogrel responsiveness in the presence of glycoprotein IIb/IIIa inhibitors. Using the P2Y12-specific, non-aggregation-based platelet-reactivity-index (PRI) we assessed clopidogrel responsiveness in patients with acute MI. Clopidogrel responsiveness was determined 24 hours (h) after loading with 600 mg clopidogrel in 54 patients with acute MI admitted for coronary intervention. A PRI > 50% was considered as suboptimal inhibition. Overall response in MI patients was suboptimal with a median PRI of 58%. Diabetes, low high-density lipoprotein and pre-hospital clopidogrel loading were associated with impaired clopidogrel responsiveness. Patients loaded at first medical contact had a significantly weaker platelet inhibition by clopidogrel after 24 h (PRI 63%) compared to those loaded peri-interventionally (PRI 54%, p=0.014). Clinical outcome was assessed as a combination of cardiac death, non-fatal MI, stent thrombosis, ischaemic stroke, and urgent target vessel revascularisation after 12 months. The pre-selected cut-off of PRI ≤ 50% yielded a sensitivity of 87% at a specificity of 26%, whereas a PRI ≤ 57% determined by receiver-operating characteristics (ROC)-analysis yielded a sensitivity of 80% at a specificity of 56% (event rate: PRI ≤ 57%: 12.0%; PRI > 57%: 41.4%, p=0.0136). In conclusion, PRI detects clopidogrel responsiveness in acute MI patients requiring glycoprotein IIb/IIIa antagonism; and impaired clopidogrel responsiveness predisposes to clinical events. Pre-hospital clopidogrel loading was associated with impaired response and more adverse events challenging the concept of earliest oral clopidogrel loading in MI patients.

Potent P2Y12 receptor inhibitors in patients with acute coronary syndrome

2013 ◽  
Vol 33 (01) ◽  
pp. 9-15 ◽  
Author(s):  
M. Orban ◽  
S. Massberg ◽  
D. Sibbing
Keyword(s):  
Acute Coronary Syndrome ◽  
Large Scale ◽  
Platelet Reactivity ◽  
Blood Platelets ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
P2y12 Receptor ◽  
Onset Of Action ◽  
Thrombotic Risk ◽  
Coronary Syndrome

SummaryBlood platelets are highly activated in the setting of an acute coronary syndrome (ACS). This fact mandates the need for potent platelet inhibition in ACS patients and especially in patients undergoing a percutaneous coronary intervention (PCI). The 2nd generation thienopyridine clopidogrel has been the standard of treatment in the past. Due to its pharmacological properties including a delayed onset of action, a large response variability and an insufficient antiplatelet action in some patients (low responsiveness or high on-treatment platelet reactivity), there was a need to develop, to study and to introduce more potent agents with a fast, reliable and potent antiplatelet action. With the 3rd generation thienopyridine prasugrel and with ticagrelor two potent agents for antiplatelet treatment of ACS patients are available now. Both drugs have demonstrated their superiority compared to clopidogrel in terms of thrombotic risk reduction in large-scale randomized trials. However, for these agents and in line with the expectations towards a more potent anti platelet treatment regimen, a higher risk for bleeding was observed for prasugrel and ticagrelor. Further on, the new anti platelet agents have their own and characteristic contraindications and numerous issues to be considered in clinical practice.This review aims to provide an overview on the state of the art P2Y12 receptor directed inhibition in ACS patients with a focus on patients undergoing a coronary stenting procedure.

Diurnal Variability of On-Treatment Platelet Reactivity in Clopidogrel versus Prasugrel Treated Acute Coronary Syndrome Patients: A Pre-Specified TROPICAL-ACS Sub-Study

2019 ◽  
Vol 119 (04) ◽  
pp. 660-667 ◽  
Author(s):  
Matthias Freynhofer ◽  
Ralph Hein-Rothweiler ◽  
Paul Haller ◽  
Daniel Aradi ◽  
Döme Dézsi ◽  
...  
Keyword(s):  
Acute Coronary Syndrome ◽  
Platelet Reactivity ◽  
Adenosine Diphosphate ◽  
Coronary Intervention ◽  
Early Morning ◽  
Platelet Inhibition ◽  
Control Group ◽  
Diurnal Variability ◽  
Coronary Syndrome ◽  
Adp Receptor

AbstractLong-term evidence supports a clustering of cardiovascular events in the early morning and smaller mechanistic studies in aspirin-treated patients have shown increased platelet reactivity at the end of the dosing interval. Comparative pharmacodynamic analyses for different adenosine diphosphate (ADP) receptor inhibitors in percutaneous coronary intervention-treated acute coronary syndrome (ACS) patients are lacking and this pre-specified analysis from the randomized Testing Responsiveness To Platelet Inhibition On Chronic Antiplatelet Treatment For Acute Coronary Syndromes (TROPICAL-ACS) trial aimed for the first time at investigating diurnal variability of on-treatment platelet reactivity in clopidogrel versus prasugrel treated patients. TROPICAL-ACS randomized 2,610 ACS patients to either treatment with prasugrel (control group) or to a platelet function testing-guided de-escalation of anti-platelet treatment with a switch to clopidogrel (guided de-escalation group). This study design enabled a diurnal comparison of on-prasugrel versus on-clopidogrel treatment platelet reactivity under steady-state conditions. For 2,526 patients (97%), both the exact time of blood sampling and the ADP-induced platelet aggregation value (in units, Multiplate analyser) were available. Platelet reactivity in patients on clopidogrel (n = 1,265) was higher and subject to significant diurnal variability (p = 0.019) with a peaking of platelet reactivity in the early morning (5–10 a.m.). In prasugrel-treated patients (n = 1,261), there was no sign for diurnal variability (p = 0.174) or a peaking of platelet reactivity in the morning. The potent ADP receptor inhibitor prasugrel is not subject to diurnal variability while we observed a significant diurnal variability of on-clopidogrel platelet reactivity. The clinical impact of this observation may differ for patients with and without an adequate response to clopidogrel treatment and the issue of diurnal variability of platelet reactivity in ACS patients warrants further investigation.

scholarly journals Impact of Intravenous P2Y12-Receptor Inhibition with Cangrelor in Patients Presenting with Acute Coronary Syndrome and Cardiogenic Shock – a Case Series

2017 ◽  
Vol 42 (4) ◽  
pp. 1336-1341 ◽  
Author(s):  
Michal Droppa ◽  
Oliver Borst ◽  
Dominik Rath ◽  
Karin Müller ◽  
Meinrad Gawaz ◽  
...  
Keyword(s):  
Cardiogenic Shock ◽  
Platelet Reactivity ◽  
Case Series ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
P2y12 Receptor ◽  
Cardiac Events ◽  
Coronary Syndrome ◽  
Multiple Electrode Aggregometry ◽  
Single Center Experience

Background/Aims: Patients with acute coronary syndromes (ACS) presenting with cardiogenic shock (CS) are at particular risk for death and adverse cardiac events. Impaired effects and absorption of oral P2Y12-receptor inhibitors due to decreased organ hypoperfusion or hypothermia and challenges regarding oral administration contribute to this risk. We report a single center experience regarding the use of intravenous P2Y12-receptor inhibitor cangrelor in patients with CS treated with percutaneous coronary intervention (PCI). Methods: Twelve patients with ACS and CS undergoing PCI, not pretreated with oral P2Y12-receptor inhibitors, were treated with cangrelor. Platelet inhibition was assessed by multiple electrode aggregometry (MEA) before and after PCI, immediately and 2 hours after stopping the cangrelor infusion. Results: Nine patients recovered from their cardiogenic shock, 3 patients died. Platelet reactivity decreased from 65.9 (SD 41.0) U before PCI to 15.8 (SD 10.8) U after PCI, 13.4 (SD 7.7) U at the end of infusion and 33.8 (SD 19.9) 2 hours after stopping the cangrelor infusion. There was no non-responder under cangrelor infusion (MEA < 46 U). Conclusions: Due to its favorable PK/PD profile, cangrelor overcomes problems with reduced absorption and effects of oral P2Y12-receptor inhibitors and should be considered for periprocedural treatment of patients with CS.

Ticagrelor vs prasugrel one-month maintenance therapy: Impact on platelet reactivity and bleeding events

2014 ◽  
Vol 112 (09) ◽  
pp. 551-557 ◽  
Author(s):  
Katerina Stavrou ◽  
Ioanna Koniari ◽  
Vassilios Gkizas ◽  
Angelos Perperis ◽  
Kosmas Kontoprias ◽  
...  
Keyword(s):  
Propensity Score ◽  
Platelet Reactivity ◽  
Academic Research ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
Bleeding Events ◽  
Clinical Trial Registration ◽  
Propensity Score Model ◽  
Coronary Syndrome

SummaryPlatelet reactivity (PR) and bleeding events following therapy with ticagrelor vs prasugrel have not been adequately studied. We aimed to compare PR and bleeding events in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) while on ticagrelor vs prasugrel for one month. Consecutive patients who were discharged either on ticagrelor 90 mg bid maintenance dose (MD) or prasugrel 10 mg MD were invited for PR assessment (VerifyNow, in PRU) at one month. High PR (HPR) was defined as >208 PRU. Bleeding events [Bleeding Academic Research Consortium (BARC) classification] were monitored. Out of 937 screened patients, 512 were analysed, 278 under ticagrelor MD and 234 under prasugrel MD. PR at 30 days (C-statistic of the propensity score model 0.63, 0.58–0.67 95% CI, p<0.001) was lower when on ticagrelor compared with prasugrel (33.3, 95% CI 29.3–37.3 vs 84.6, 95% CI 73.6–95.6, p<0.001). In the analysed population more BARC type 1 bleeding events were observed with ticagrelor compared to prasugrel (36.7% vs 28.2%, p=0.047). In 221 propensity score matched pairs, BARC type 1 bleeding rate was marginally higher in ticagrelor vs prasugrel treated patients (35.7% vs 27.1%, p=0.05). BARC type ≥2 events did not differ between groups 5 (2.3%) vs 5 (2.3%). HPR rate was higher for prasugrel-treated patients (5.4% vs 0%, p<0.001). In conclusion, in patients with ACS undergoing PCI, ticagrelor MD produces a significantly higher platelet inhibition compared to prasugrel MD. This pharmacodynamic difference might be associated with more nuisance bleeding events with ticagrelor use.Clinical Trial Registration ClinicalTrials.gov Identifier: NCT01774955.

Impact of Reticulated Platelets on the Antiplatelet Effect of the Intravenous P2Y12-Receptor Inhibitor Cangrelor

2018 ◽  
Vol 118 (02) ◽  
pp. 362-368 ◽  
Author(s):  
Christian Stratz ◽  
Thomas Nührenberg ◽  
Christian Valina ◽  
Nikolaus Löffelhardt ◽  
Kambis Mashayekhi ◽  
...  
Keyword(s):  
Platelet Reactivity ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
P2y12 Receptor ◽  
Elective Percutaneous Coronary Intervention ◽  
Reticulated Platelets ◽  
Impedance Aggregometry ◽  
Percutaneous Coronary ◽  
The Impact ◽  
Receptor Inhibitor

Background Reticulated platelets are associated with impaired antiplatelet response to irreversibly acting P2Y12-receptor inhibitors. However, the impact of reticluated platelets (RP) on the reversibly acting injectable P2Y12-receptor inhibitor cangrelor is unknown. Thus, this study sought to investigate the influence of RP on cangrelor and transitioning strategies to oral P2Y12-receptor inhibitors. Methods This study randomized 110 patients undergoing elective percutaneous coronary intervention with use of cangrelor to different oral transitioning strategies loading with prasugrel 60 mg or ticagrelor 180 mg at the start of cangrelor (n = 45 each) or loading with clopidogrel 600 mg after discontinuation of cangrelor (n = 20). ADP-induced platelet reactivity was assessed by impedance aggregometry. Reticulated platelets were analysed by an automated whole blood flow cytometry and described as immature platelet count. Results There was no correlation of reticulated platelets and ADP-induced platelet reactivity in patients under treatment with cangrelor (r = 0.06, p = 0.47). This finding was consistent in all three transitioning strategies. On day 1 following treatment with cangrelor, the correlation of reticulated platelets and platelet reactivity was detectable again in patients receiving thienopyridines but not ticagrelor (all patients r = 0.37, p < 0.001; clopidogrel: r = 0.59, p = 0.01; prasugrel: r = 0.47, p < 0.001; ticagrelor r = 0.22, p = 0.13). Conclusion Platelet inhibition is not influenced by levels of reticulated platelets during infusion of cangrelor independent of oral P2Y12-receptor inhibitor transitioning strategy. These findings underline the potency of cangrelor as immediate and reversibly acting P2Y12-receptor inhibitor.

The ABCB1, CYP2C19, CYP3A5 and CYP4F2 genetic polymorphisms and platelet reactivity in the early phases of acute coronary syndromes

2018 ◽  
Vol 33 (3) ◽  
pp. 109-118 ◽  
Author(s):  
Karin B. Mirzaev ◽  
Eric Rytkin ◽  
Kristina A. Ryzhikova ◽  
Elena A. Grishina ◽  
Zhannet A. Sozaeva ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Antiplatelet Therapy ◽  
Early Phase ◽  
Platelet Reactivity ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
Categorical Variables ◽  
P Value ◽  
Coronary Syndrome ◽  
Significant Difference

Abstract Background 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). Methods 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. Results 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. Conclusions 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.

Transferring from clopidogrel loading dose to prasugrel loading dose in acute coronary syndrome patients

2014 ◽  
Vol 112 (08) ◽  
pp. 311-322 ◽  
Author(s):  
Jorge F. Saucedo ◽  
Tracy E. Cardillo ◽  
Joseph A. Jakubowski ◽  
Carsten Henneges ◽  
Mark B. Effron ◽  
...  
Keyword(s):  
Acute Coronary Syndrome ◽  
Platelet Reactivity ◽  
Coronary Intervention ◽  
Loading Dose ◽  
Coronary Syndrome ◽  
Percutaneous Coronary ◽  
Significant Difference ◽  
High Prevalence ◽  
The Impact ◽  
Time Point

SummaryHigh on-treatment platelet reactivity (HPR) has been identified as an independent risk factor for ischaemic events. The randomised, doubleblind, TRIPLET trial included a pre-defined comparison of HPR in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) following a placebo/600-mg clopidogrel loading dose (LD) immediately before a subsequent prasugrel 60-mg or 30-mg LD. Platelet reactivity was assessed using the VerifyNow® P2Y12 assay (P2Y12 Reaction Units, PRU) within 24 hours (h) following the placebo/clopidogrel LD (immediately prior to prasugrel LD), and at 2, 6, 24, 72 h following prasugrel LDs. The impact of CYP2C19 predicted metaboliser phenotype (extensive metaboliser [EM] and reduced metabolisers [RM]) on HPR status was also assessed. HPR (PRU ≥240) following the clopidogrel LD (prior to the prasugrel LD) was 58.5% in the combined clopidogrel LD groups. No significant difference was noted when stratified by time between the clopidogrel and prasugrel LDs (≤6 hs vs >6 h). At 6 h following the 2nd loading dose in the combined prasugrel LD groups, HPR was 7.1%, with 0% HPR by 72 h. There was no significant effect of CYP2C19 genotype on pharmacodynamic (PD) response following either prasugrel LD treatments at any time point, regardless of whether it was preceded by a clopidogrel 600-mg LD. In conclusion, in this study, patients with ACS intended for PCI showed a high prevalence of HPR after clopidogrel 600-mg LD regardless of metaboliser status. When prasugrel LD was added, HPR decreased substantially by 6 h, and was not seen by 72 h.

scholarly journals The effect of CYP2C19 gene polymorphisms on the pharmacokinetics and pharmacodynamics of prasugrel 5-mg, prasugrel 10-mg and clopidogrel 75-mg in patients with coronary artery disease

2014 ◽  
Vol 112 (09) ◽  
pp. 589-597 ◽  
Author(s):  
Thomas Bergmeijer ◽  
Udaya Tantry ◽  
Jurrien ten Berg ◽  
Dominick Angiolillo ◽  
Stefan James ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Active Metabolite ◽  
Light Transmission ◽  
Platelet Reactivity ◽  
Stable Coronary Artery Disease ◽  
Geometric Mean ◽  
Reactivity Index ◽  
Cyp2c19 Genotype ◽  
Artery Disease

Summary CYP2C19 genotype has been shown to impact response to clopidogrel 75-mg but not prasugrel 10-mg. Here, we assessed effects of CYP2C19 metaboliser status on pharmacokinetics (PK) and pharmacodynamic (PD) responses to prasugrel 5-mg and 10-mg and clopidogrel 75-mg using data from two PK/PD studies in stable coronary artery disease (CAD) patients (GENERATIONS and FEATHER). Active metabolite concentrations (area under the curve, AUC[0-tlast]), maximum platelet aggregation (MPA) measured by light transmission aggregometry, vasodilator- stimulated phosphoprotein platelet reactivity index, and VerifyNow P2Y12-platelet reaction units (VN-PRU) were analysed by CYP2C19-predicted phenotype (extensive metaboliser [EM; N=154], *2-*8 non-carriers, vs reduced metaboliser [RM; N=41],*2-*8 carriers/* 17 non-carriers). AUC(0-tlast) was unaffected by metaboliser status for prasugrel 5-mg and 10-mg (geometric mean EM/RM ratios 1.00, 95% confidence interval [CI]: 0.86,1.17, p>0.99; and 0.97, 95% CI:0.85,1.12, p=0.71, respectively), but was lower among RMs receiving clopidogrel 75-mg (1.37, 95% CI:1.14,1.65, p<0.001). Platelet reactivity was not significantly affected by CYP2C19 metaboliser status for prasugrel 5-mg, or for prasugrel 10-mg by MPA and VNPRU, but for clopidogrel 75-mg was significantly higher in reduced metabolisers (all measures p<0.01). Prasugrel 10-mg showed greater antiplatelet effects vs clopidogrel 75-mg (all comparisons p<0.001). Prasugrel 5-mg showed greater antiplatelet effects vs clopidogrel 75-mg in RMs (all p<0.001), and comparable effects in EMs (all p≥0.37). In contrast to clopidogrel, prasugrel active metabolite PK was not influenced by CYP2C19 genotype. Antiplatelet effect for prasugrel 10-mg was greater irrespective of metaboliser status and for prasugrel 5-mg was greater for RMs and comparable for EMs as compared to clopidogrel 75-mg.

Sign in / Sign up

Export Citation Format

Share Document