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Background: Various antiplatelet drugs are used following Acute Coronary Syndromes (ACS). Of them, adenosine diphosphate receptor P2Y12 inhibitors clopidogrel, prasugrel and ticagrelor are currently used for post-ACS long-term treatment. Although they act on the same receptor, they differ in pharmacodynamics and pharmacokinetics. Several enzymes and transporters involved in the metabolism of P2Y12 inhibitors show genetic variability with functional impact. This includes Pglycoprotein, carboxylesterase 1 and, most notably, CYP2C19 that is important in clopidogrel activation. Common gain-of-function or loss-of-function alleles of CYP2C19 gene are associated with lower or higher platelet reactivity that may impact clinical outcomes of clopidogrel treatment. Prasugrel is considered to be less dependent on CYP2C19 variability as it is also metabolized by other CYP450 isoforms. Some studies, however, showed the relevance of CYP2C19 variants for platelet reactivity during prasugrel treatment as well. Ticagrelor is metabolized mainly by CYP3A4, which does not show functionally relevant genetic variability. Its concentrations may be modified by the variants of Pglycoprotein gene ABCB1. While no substantial difference between the clinical efficacy of prasugrel and ticagrelor has been documented, both of them have been shown to be superior to clopidogrel in post-ACS treatment. This can be partially explained by lower variability at each step of their metabolism. It is probable that factors influencing the pharmacokinetics of both drugs, including genetic factors, may predict the clinical efficacy of antiplatelet treatment in personalized medicine., Conclusion: We summarize the pharmacokinetics and pharmacogenetics of P2Y12 inhibitors with respect to their clinical effects in post-myocardial infarction treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Early outcomes of patients in the PRAGUE-18 (Comparison of Prasugrel and Ticagrelor in the Treatment of Acute Myocardial Infarction) study did not find any significant differences between 2 potent P2Y 12 inhibitors., Objectives: The 1-year follow-up of the PRAGUE-18 study focused on: 1) a comparison of efficacy and safety between prasugrel and ticagrelor; and 2) the risk of major ischemic events related to an economically motivated post-discharge switch to clopidogrel., Methods: A total of 1,230 patients with acute myocardial infarction (MI) treated with primary percutaneous coronary intervention were randomized to prasugrel or ticagrelor with an intended treatment duration of 12 months. The combined endpoint was cardiovascular death, MI, or stroke at 1 year. Because patients had to cover the costs of study medication after hospital discharge, some patients decided to switch to clopidogrel., Results: The endpoint occurred in 6.6% of prasugrel patients and in 5.7% of ticagrelor patients (hazard ratio: 1.167; 95% confidence interval: 0.742 to 1.835; p = 0.503). No significant differences were found in: cardiovascular death (3.3% vs. 3.0%; p = 0.769), MI (3.0% vs. 2.5%; p = 0.611), stroke (1.1% vs. 0.7%; p = 0.423), all-cause death (4.7% vs. 4.2%; p = 0.654), definite stent thrombosis (1.1% vs. 1.5%; p = 0.535), all bleeding (10.9% vs. 11.1%; p = 0.999), and TIMI (Thrombolysis In Myocardial Infarction) major bleeding (0.9% vs. 0.7%; p = 0.754). The percentage of patients who switched to clopidogrel for economic reasons was 34.1% (n = 216) for prasugrel and 44.4% (n = 265) for ticagrelor (p = 0.003). Patients who were economically motivated to switch to clopidogrel had (compared with patients who continued the study medications) a lower risk of major cardiovascular events; however, they also had lower ischemic risk., Conclusions: Prasugrel and ticagrelor are similarly effective during the first year after MI. Economically motivated early post-discharge switches to clopidogrel were not associated with an increased risk of ischemic events. (Comparison of Prasugrel and Ticagrelor in the Treatment of Acute Myocardial Infarction [PRAGUE-18]; NCT02808767)., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Whether ticagrelor in chronic coronary syndrome patients undergoing complex percutaneous coronary intervention (PCI) can prevent cardiovascular events is unknown. The authors sought to evaluate outcomes of complex PCI and the efficacy of ticagrelor vs clopidogrel in stable patients randomized in the ALPHEUS (Assessment of Loading with the P2Y 12 inhibitor ticagrelor or clopidogrel to Halt ischemic Events in patients Undergoing elective coronary Stenting) trial. All PCI procedures were blindly reviewed and classified as complex if they had at least 1 of the following criteria: stent length >60 mm, 2-stent bifurcation, left main, bypass graft, chronic total occlusion, use of atherectomy or guiding catheter extensions, multiwire technique, multiple stents. The primary endpoint was a composite of type 4a or b myocardial infarction (MI) and major myocardial injury during the 48 hours after PCI. We compared the event rates according to the presence or not of complex PCI criteria and evaluated the interaction with ticagrelor or clopidogrel. Among the 1,866 patients randomized, 910 PCI (48.3%) were classified as complex PCI. The primary endpoint was more frequent in complex PCI (45.6% vs 26.6%; P < 0.001) driven by higher rates of type 4 MI and angiographic complications (12.2% vs 4.8 %; P < 0.001 and 19.3% vs 8.6%; P < 0.05, respectively). The composite of death, MI, and stroke at 48 hours (12.7% vs 5.1 %; P < 0.05) and at 30 days (13.4% vs 5.3%; P < 0.05) was more frequent in complex PCI. No interaction was found between PCI complexity and the randomized treatment for the primary endpoint (P interaction = 0.47) nor the secondary endpoints. In chronic coronary syndrome, patients undergoing a complex PCI have higher rates of periprocedural and cardiovascular events that are not reduced by ticagrelor as compared with clopidogrel. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: No randomized head-to-head comparison of the efficacy and safety of ticagrelor and prasugrel has been published in the 7 years since the higher efficacy of these newer P2Y12 inhibitors were first demonstrated relative to clopidogrel.Methods: This academic study was designed to compare the efficacy and safety of prasugrel and ticagrelor in acute myocardial infarction treated with primary or immediate percutaneous coronary intervention. A total of 1230 patients were randomly assigned across 14 sites to either prasugrel or ticagrelor, which was initiated before percutaneous coronary intervention. Nearly 4% were in cardiogenic shock, and 5.2% were on mechanical ventilation. The primary end point was defined as death, reinfarction, urgent target vessel revascularization, stroke, or serious bleeding requiring transfusion or prolonging hospitalization at 7 days (to reflect primarily the in-hospital phase). This analysis presents data from the first 30 days (key secondary end point). The total follow-up will be 1 year for all patients and will be completed in 2017.Results: The study was prematurely terminated for futility. The occurrence of the primary end point did not differ between groups receiving prasugrel and ticagrelor (4.0% and 4.1%, respectively; odds ratio, 0.98; 95% confidence interval, 0.55-1.73; P=0.939). No significant difference was found in any of the components of the primary end point. The occurrence of key secondary end point within 30 days, composed of cardiovascular death, nonfatal myocardial infarction, or stroke, did not show any significant difference between prasugrel and ticagrelor (2.7% and 2.5%, respectively; odds ratio, 1.06; 95% confidence interval, 0.53-2.15; P=0.864).Conclusions: This head-to-head comparison of prasugrel and ticagrelor does not support the hypothesis that one is more effective or safer than the other in preventing ischemic and bleeding events in the acute phase of myocardial infarction treated with a primary percutaneous coronary intervention strategy. The observed rates of major outcomes were similar but with broad confidence intervals around the estimates. These interesting observations need to be confirmed in a larger trial.Clinical Trial Registration: URL: http://www.ClinicalTrials.gov. Unique identifier: NCT02808767. [ABSTRACT FROM AUTHOR]

Drug-eluting stents (DES) are the recommended stents for primary percutaneous coronary intervention (PCI). This study aimed to determine why interventional cardiologists used non-DES and how it influenced patient prognoses. The efficacy and safety outcomes of the different stents were also compared in patients treated with either prasugrel or ticagrelor. Of the PRAGUE-18 study patients, 749 (67.4%) were treated with DES, 296 (26.6%) with bare-metal stents (BMS), and 66 (5.9%) with bioabsorbable vascular scaffold/stents (BVS) between 2013 and 2016. Cardiogenic shock at presentation, left main coronary artery disease, especially as the culprit lesion, and right coronary artery stenosis were the reasons for selecting a BMS. The incidence of the primary composite net-clinical endpoint (EP) (death, nonfatal myocardial infarction, stroke, serious bleeding, or revascularization) at seven days was 2.5% vs. 6.3% and 3.0% in the DES, vs. with BMS and BVS, respectively (HR 2.7; 95% CI 1.419–5.15, p = 0.002 for BMS vs. DES and 1.25 (0.29–5.39) p = 0.76 for BVS vs. DES). Patients with BMS were at higher risk of death at 30 days (HR 2.20; 95% CI 1.01–4.76; for BMS vs. DES, p = 0.045) and at one year (HR 2.1; 95% CI 1.19–3.69; p = 0.01); they also had a higher composite of cardiac death, reinfarction, and stroke (HR 1.66; 95% CI 1.0–2.74; p = 0.047) at one year. BMS were associated with a significantly higher rate of primary EP whether treated with prasugrel or ticagrelor. In conclusion, patients with the highest initial risk profile were preferably treated with BMS over BVS. BMS were associated with a significantly higher rate of cardiovascular events whether treated with prasugrel or ticagrelor. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prognostic significance of diabetes mellitus (DM) in patients with high risk acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (pPCI) in the era of potent antithrombotics. Methods: Data from 1230 ST-segment elevation myocardial infarction (STEMI) patients enrolled in the PRAGUE-18 (prasugrel vs. ticagrelor in pPCI) study were analyzed. Ischemic and bleeding event rates were calculated for patients with and without diabetes. The independent impact of diabetes on outcomes was evaluated after adjustment for outcome predictors. Results: The prevalence of DM was 20% (N = 250). Diabetics were older and more often female. They were more likely to have hypertension, hyperlipoproteinemia, multivessel coronary disease and left main disease, and be obese. The primary net-clinical endpoint (EP) containing death, spontaneous nonfatal MI, stroke, severe bleeding, and revascularization at day 7 occurred in 6.1% of patients with, and in 3.5% of patients without DM (HR 1.8; 95% CI 0.978–3.315; p = 0.055). At one year, the key secondary endpoint defined as cardiovascular death, spontaneous MI, or stroke occurred in 8.8% with, and 5.5% without DM (HR 1.621; 95% CI 0.987–2.661; p = 0.054). In those with DM the risk of total one-year mortality (6.8% vs. 3.9% (HR 1.773; 95% CI 1.001–3.141; p = 0.047)) and the risk of nonfatal reinfarction (4.8% vs. 2.2% (HR 2.177; 95% CI 1.077–4.398; p = 0.026)) were significantly higher compared to in those without DM. There was no risk of major bleeding associated with DM (HR 0.861; 95% CI 0.554–1.339; p = 0.506). In the multivariate analysis, diabetes was independently associated with the one-year risk of reinfarction (HR 2.176; 95% Confidence Interval, 1.055–4.489; p = 0.035). Conclusion: Despite best practices STEMI treatment, diabetes is still associated with significantly worse prognoses, which highlights the importance of further improvements in the management of this high-risk population. [ABSTRACT FROM AUTHOR]