Platelet inhibition with ticagrelor versus clopidogrel in Hispanic patients with stable coronary artery disease with or without diabetes mellitus

Antiplatelet efficacy of ticagrelor versus clopidogrel in Mediterranean patients with diabetes mellitus and chronic coronary syndromes: A crossover pharmacodynamic investigation

Introduction

Patients with diabetes mellitus (DM) have augmented platelet reactivity and diminished responsiveness to clopidogrel. Ticagrelor, a more potent P2Y12 inhibitor, is clinically superior to clopidogrel in acute coronary syndromes, although its role in chronic coronary syndromes (CCS) is still the subject of debate. The aim of this investigation was to compare the pharmacodynamic effectiveness of ticagrelor and clopidogrel in Mediterranean DM patients with CCS.

Materials and methods

In this prospective, randomized, crossover study, patients (n = 20) were randomized (1:1) to receive, on top of aspirin therapy, either ticagrelor 180 mg loading dose (LD)/90 mg maintenance dose (MD) b.i.d. or clopidogrel 600 mg LD/75 mg MD o.d. for 1 week in a crossover fashion with a 2–4 week washout period between regimens. Platelet function measurements were performed at 4 timepoints in each period (baseline, 2 h and 24 h after LD, and 1 week), including light transmission aggregometry (LTA, primary endpoint), VASP assay, Multiplate and VerifyNow P2Y12.

Results

The ticagrelor LD achieved greater platelet inhibitory effect than clopidogrel LD, assessed with LTA (20 μM ADP as agonist), at 2 h (34.9 ± 3.9% vs. 63.6 ± 3.9%; p < 0.001) and 24 h (39.4 ± 3.5% vs. 52.3 ± 3.8%; p = 0.014). After 1 week of therapy, platelet reactivity was again significantly inferior with ticagrelor compared to clopidogrel (30.7 ± 3.0% vs. 54.3 ± 3.0%; p < 0.001). The results were consistent with the other platelet function assays employed.

Conclusion

In Mediterranean patients with DM and CCS, ticagrelor provides a more potent antiplatelet effect than clopidogrel after the LD and during the maintenance phase of therapy.

Clinical trial registration

[ClinicalTrials.gov], identifier [NCT02457130].

Physiologically-Based Pharmacokinetic-Pharmacodynamics Model Characterizing CYP2C19 Polymorphisms to Predict Clopidogrel Pharmacokinetics and Its Anti-Platelet Aggregation Effect Following Oral Administration to Coronary Artery Disease Patients With or Without Diabetes

Background and Objective: Clopidogrel (CLOP) is commonly used in coronary artery disease (CAD) patients with or without diabetes (DM), but these patients often suffer CLOP resistance, especially those with diabetes. This study was aimed to develop a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to describe the pharmacokinetics and pharmacodynamics of clopidogrel active metabolite (CLOP-AM) in CAD patients with or without DM.

Methods: The PBPK-PD model was first established and validated in healthy subjects and then in CAD patients with or without DM. The influences of CYP2C19, CYP2C9, CYP3A4, carboxylesterase 1 (CES1), gastrointestinal transit rates (K_t,i) and platelets response to CLOP-AM (k_irre) on predicted pharmacokinetics and pharmacodynamics were investigated, followed with their individual and integrated effects on CLOP-AM pharmacokinetics due to changes in DM status.

Results: Most predictions fell within 0.5–2.0 folds of observations, indicating successful predictions. Sensitivity analysis showed that contributions of interested factors to pharmacodynamics were CES1> k_irre> K_t,i> CYP2C19 > CYP3A4> CYP2C9. Mimicked analysis showed that the decreased exposure of CLOP-AM by DM was mainly attributed to increased CES1 activity, followed by decreased CYP2C19 activity.

Conclusion: The pharmacokinetics and pharmacodynamics of CLOP-AM were successfully predicted using the developed PBPK-PD model. Clopidogrel resistance by DM was the integrated effects of altered K_t,i, CYP2C19, CYP3A4, CES1 and k_irre.

Antithrombotic Therapy for Atherosclerotic Cardiovascular Disease Risk Mitigation in Patients With Coronary Artery Disease and Diabetes Mellitus

Patients with diabetes mellitus (DM) are characterized by enhanced thrombotic risk attributed to multiple mechanisms including hyperreactive platelets, hypercoagulable status, and endothelial dysfunction. As such, they are more prone to atherosclerotic cardiovascular events than patients without DM, both before and after coronary artery disease (CAD) is established. In patients with DM without established CAD, primary prevention with aspirin is not routinely advocated because of its increased risk of major bleeding that largely offsets its ischemic benefit. In patients with DM with established CAD, secondary prevention with antiplatelet drugs is an asset of pharmacological strategies aimed at reducing the risk of atherosclerotic cardiovascular events and their adverse prognostic consequences. Such antithrombotic strategies include single antiplatelet therapy (eg, with aspirin or a P2Y₁₂ inhibitor), dual antiplatelet therapy (eg, aspirin combined with a P2Y₁₂ inhibitor), and dual-pathway inhibition (eg, aspirin combined with the vascular dose of the direct oral anticoagulant rivaroxaban) for patients with chronic ischemic heart disease, acute coronary syndromes, and those undergoing percutaneous coronary intervention. Because of their increased risk of thrombotic complications, patients with DM commonly achieve enhanced absolute benefit from more potent antithrombotic approaches compared with those without DM, which most often occurs at the expense of increased bleeding. Nevertheless, studies have shown that when excluding individuals at high risk for bleeding, the net clinical benefit favors the use of intensified long-term antithrombotic therapy in patients with DM and CAD. Several studies are ongoing to establish the role of novel antithrombotic strategies and drug formulations in maximizing the net benefit of antithrombotic therapy for patients with DM. The scope of this review article is to provide an overview of current and evolving antithrombotic strategies for primary and secondary prevention of atherosclerotic cardiovascular events in patients with CAD and DM.

Impact of Diabetes Mellitus and Chronic Kidney Disease on Cardiovascular Outcomes and Platelet P2Y12 Receptor Antagonist Effects in Patients With Acute Coronary Syndromes: Insights From the PLATO Trial

Background

There are limited data on how the combination of diabetes mellitus (DM) and chronic kidney disease (CKD) affects cardiovascular outcomes as well as response to different P2Y₁₂ receptor antagonists, which represented the aim of the present investigation.

Methods and Results

In this post hoc analysis of the PLATO (Platelet Inhibition and Patient Outcomes) trial, which randomized acute coronary syndrome patients to ticagrelor versus clopidogrel, patients (n=15 108) with available DM and CKD status were classified into 4 groups: DM+/CKD+ (n=1058), DM+/CKD− (n=2748), DM−/CKD+ (n=2160), and DM−/CKD− (n=9142). The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or stroke at 12 months. The primary safety end point was PLATO major bleeding. DM+/CKD+ patients had a higher incidence of the primary end point compared with DM−/CKD− patients (23.3% versus 7.1%; adjusted hazard ratio 2.22; 95% CI 1.88–2.63; P<0.001). Patients with DM+/CKD− and DM−/CKD+ had an intermediate risk profile. The same trend was shown for the individual components of the primary end point and for major bleeding. Compared with clopidogrel, ticagrelor reduced the incidence of the primary end point consistently across subgroups (P‐interaction=0.264), but with an increased absolute risk reduction in DM+/CKD+. The effects on major bleeding were also consistent across subgroups (P‐interaction=0.288).

Conclusions

In acute coronary syndrome patients, a gradient of risk was observed according to the presence or absence of DM and CKD, with patients having both risk factors at the highest risk. Although the ischemic benefit of ticagrelor over clopidogrel was consistent in all subgroups, the absolute risk reduction was greatest in patients with both DM and CKD.

Clinical Trial Registration

URL: http://www.clinicatrials.gov. Unique identifier: NCT00391872.

Platelet Inhibition with Ticagrelor versus Clopidogrel in Diabetic Patients after Percutaneous Coronary Intervention for Chronic Coronary Syndromes

BACKGROUND

 Clopidogrel is currently the only P2Y₁₂ inhibitor with class I recommendation in patients after percutaneous coronary intervention (PCI) for chronic coronary syndromes (CCS). Diabetic patients have reduced therapeutic response to clopidogrel.

PURPOSE

 This study assessed the antiplatelet effect of ticagrelor versus clopidogrel in diabetic patients after recent PCI for CCS.

METHODS

 Eligible patients were randomly assigned to receive ticagrelor 90 mg twice daily or clopidogrel 75 mg once daily, in addition to aspirin 100 mg once daily for 15 days. P2Y₁₂ reaction unit (PRU) and percent inhibition were measured by VerifyNow P2Y₁₂ assay. High on-treatment platelet reactivity (HOPR) was defined as PRU > 208. Bleeding was assessed by the Platelet Inhibition and Patient Outcomes criteria. Cardiac ischemic events were evaluated as adverse events.

RESULTS

 The baseline characteristics of the patients (n = 39) were well balanced between the two groups. Both before and 2 to 4 hours after the final study dose on day 15, PRU was lower (41.3 ± 35.8 vs. 192.6 ± 49.5, p < 0.001; 36.6 ± 25.8 vs. 187.6 ± 70.9, p < 0.001), percent inhibition was higher (83.0% [70.5%, 96.0%] vs. 16.0% [0%, 25.0%], p < 0.001; 85.0% [76.0%, 96.5%] vs. 25.0% [0%, 39.0%], p < 0.001), and HOPR occurred less frequently (0% [0/20] vs. 26.3% [5/19], p = 0.020; 0% [0/20] vs. 31.6% [6/19], p = 0.008) in the ticagrelor group (n = 20) compared with the clopidogrel group (n = 19). No major or minor bleeding, or serious adverse events occurred in both groups.

CONCLUSION

 Ticagrelor achieved greater peak and trough platelet inhibition than did clopidogrel in diabetic patients after recent PCI for CCS, which suggests the potential use of ticagrelor in this clinical setting.

Ticagrelor Versus Prasugrel for the Treatment of Patients with Type 2 Diabetes Mellitus Following Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

INTRODUCTION

Antiplatelet therapy is very important following percutaneous coronary intervention (PCI). New generation P2Y₁₂ inhibitors (ticagrelor and prasugrel) might potentially replace clopidogrel for the treatment of post-interventional acute coronary syndrome (ACS). In this analysis, we aimed to systematically compare the post-interventional clinical outcomes and bleeding events observed with ticagrelor versus prasugrel in patients with type 2 diabetes mellitus (T2DM).

METHODS

EMBASE, MEDLINE, the Cochrane Central Register of Controlled Trials, and www.ClinicalTrials.gov were carefully searched for publications comparing the post-coronary interventional outcomes following ticagrelor versus prasugrel use in patients with T2DM. Adverse clinical outcomes and bleeding events were considered as the endpoints. Statistical analysis was carried out by the Revman software (version 5.3). Odds ratios (OR) and 95% confidence intervals (CI) were used to represent the data during subgroup analysis.

RESULTS

A total of 2004 participants with T2DM were included in this analysis. Following PCI, mortality (OR 1.00, 95% CI 0.57-1.76; P = 0.99, I² = 19%), myocardial infarction (OR 0.86, 95% CI 0.42-1.75; P = 0.67, I² = 0%), major adverse cardiac events (OR 0.73, 95% CI 0.42-1.27; P = 0.27, I² = 0%), and stroke (OR 0.72, 95% CI 0.20-2.59; P = 0.61, I² = 0%) were not significantly different between ticagrelor and prasugrel. In addition, total bleeding events (OR 0.87, 95% CI 0.55-1.40; P = 0.58, I² = 6%), Thrombolysis in Myocardial Infarction (TIMI) defined minor bleeding (OR 2.39, 95% CI 0.58-9.91; P = 0.23, I² = 0%), TIMI defined major bleeding (OR 1.42, 95% CI 0.27-7.45; P = 0.68, I² = 0%), bleeding defined according to the Bleeding Academic Research Consortium (BARC) major bleeding (OR 0.55, 95% CI 0.22-1.36; P = 0.20, I² = 0%), BARC minor bleeding (OR 1.44, 95% CI 0.52-3.99; P = 0.48, I² = 0%), and total minimal bleeding (OR 3.12, 95% CI 0.55-17.59; P = 0.20, I² = 0%) were also not significantly different.

CONCLUSION

Ticagrelor and prasugrel were not associated with significantly different adverse clinical outcomes and bleeding events in these patients with T2DM. Therefore, both antiplatelet agents might safely be used in patients with T2DM following coronary intervention. However, this head-to-head comparison still remains a major challenge which should be resolved in larger clinical trials.

Antithrombotic potency of ticagrelor versus clopidogrel in type-2 diabetic patients with cardiovascular disease

Type-2 Diabetes Mellitus [T2DM] is associated with increased platelet reactivity and hypo-response to antiplatelet drugs. Ticagrelor, with its faster and more potent antiplatelet effects, was shown to reduce adverse events more than clopidogrel in the overall CAD patient population of PLATO trial, but the benefits did not reach statistical significance in the T2DM subgroup. To better understand these findings, we compared the antithrombotic effects of ticagrelor versus with clopidogrel in T2DM patients with cardiovascular disease. In a randomized, 2 treatment-sequence, crossover-design, T2DM patients (n=20, 57±8 years, 60% male) received a loading-dose [LD] plus one week of daily-therapy [DT] of clopidogrel or ticagrelor. Treatment effects were assessed by measuring thrombus formation (Badimon Chamber) and platelet aggregation (Multiple Electrode Aggregometry (MEA) Analyzer and VerifyNow®) at 2- and 6-hour post-LD and on Day-7 of DT, in comparison with pre-treatment baseline. After 2 weeks of washout, patients switched to the second treatment under identical testing conditions. Ticagrelor significantly reduced thrombus formation versus baseline at 2- and 6-hour post-LD and Day-7 of DT (33%, 40% and 31%, respectively, p<0.01 for all) whereas thrombus reductions with clopidogrel were much lower and significant only at 6-hour post-LD (16%, 20% and 17%, respectively). Antithrombotic effect of ticagrelor at 6-hour was significantly stronger than clopidogrel (p<0.05). Platelet aggregation (MEA and VerifyNow®) was inhibited by both treatments but effects of ticagrelor were significantly stronger at each time-point. Ticagrelor exhibits a faster and more potent antithrombotic effect than clopidogrel in T2DM patients with cardiovascular disease, supporting its use in this population.

Clinical Trial Registration: Unique Identifier: NCT01823510.

Supplementary Material to this article is available online at www.thrombosis-online.com.

The clinical efficacy and safety evaluation of ticagrelor for acute coronary syndrome in general ACS patients and diabetic patients: A systematic review and meta-analysis

Objective

In this study, a systematic evaluation was conducted to estimate the efficacy and safety of ticagrelor for treating acute coronary syndrome (ACS) in general ACS patients and a diabetes mellitus (DM) group.

Methods

A search of PubMed, Cochrane Central Register of Controlled Trials, Web of Science, CNKI databases was conducted to analyze relevant randomized controlled trails (RCTs) of ticagrelor treating ACS during 2007 to 2015. Article screening, quality accessing and data extracting was independently undertaken by two reviewers. A meta-analysis was performed to clarify the efficacy and safety of ticagrelor in general ACS patients, and a meta-regression analysis was taken to demonstrate the efficacy and safety of ticagrelor in DM patients compared with general ACS patients.

Result

Twenty-two studies with 35004 participants were included. The meta-analysis result implicated that ticagrelor could: 1) reduce the incidence of the composite endpoint [OR = 0.83, 95%CI (0.77, 0.90), P<0.00001] and the incidence of myocardial infarction [OR = 0.81, 95%CI (0.74, 0.89), P = 0.0001]; 2) not statistically reduce the incidence of cardiovascular death, the incidence of stroke and the incidence of bleeding events; 3) increase the incidence of dyspnea [OR = 1.90, 95%CI (1.73, 2.08), P<0.00001] compared with clopidogrel. Meanwhile, compared with prasugrel, ticagrelor could 1) reduce the platelet reactivity of patients at maintenance dose [MD = -44.59, 95%CI (-59.16, -30.02), P<0.00001]; 2) not statistically reduce the incidence of cardiovascular death, the platelet reactivity of patients 6 hours or 8 hours after administration, or the incidence of bleeding events; 3) induce the incidence of dyspnea [OR = 13.99, 95%CI (2.58, 75.92), P = 0.002]. Furthermore, the result of meta-regression analysis implicated that there was a positive correlation between DM patients and the platelet reactivity of patients 6 hours and 8 hours after administration, but there was no obvious correlation between DM patients and general ACS patients in other endpoints.

Conclusion

Ticagrelor could reduce the incidence of composite endpoint of cardiovascular death, myocardial infarction and stroke as well as platelet reactivity in DM patients with ACS, while not increasing the risk of bleeding. Because there are differences in platelet reactivity between DM patients and general ACS patients, we suggest that caution is needed when using ticagrelor in clinical applications.

Randomized Trial Comparing the Effects of Ticagrelor Versus Clopidogrel on Myocardial Perfusion in Patients With Coronary Artery Disease

Background

Ticagrelor is a P2Y₁₂ receptor inhibitor used in acute coronary syndromes to reduce platelet activity and to decrease thrombus formation. Ticagrelor is associated with a reduction in mortality incremental to that observed with clopidogrel, potentially related to its non–antiplatelet effects. Evidence from animal models indicates that ticagrelor potentiates adenosine‐induced myocardial blood flow (MBF) increases. We investigated MBF at rest and during adenosine‐induced hyperemia in patients with stable coronary artery disease treated with ticagrelor versus clopidogrel.

Methods and Results

This randomized double‐blinded crossover study included 22 patients who received therapeutic interventions of ticagrelor 90 mg orally twice a day for 10 days and clopidogrel 75 mg orally once a day for 10 days, with a washout period of at least 10 days between the treatments. Global and regional MBF and myocardial flow reserve were measured using rubidium 82 positron emission tomography/computed tomography at baseline and during intermediate‐ and high‐dose adenosine. Global MBF was significantly greater with ticagrelor versus clopidogrel (1.28±0.55 versus 1.13±0.47 mL/min per gram, P=0.002) at intermediate‐dose adenosine and not different at baseline (0.65±0.19 versus 0.60±0.15 mL/min per gram, P=0.084) and at high‐dose adenosine (1.64±0.40 versus 1.61±0.19 mL/min per gram, P=0.53). In regions with impaired myocardial flow reserve (<2.5), MBF was greater with ticagrelor compared with clopidogrel during intermediate and high doses of adenosine (P<0.0001), whereas the differences were not significant at baseline.

Conclusions

Ticagrelor potentiates global and regional adenosine‐induced MBF increases in patients with stable coronary artery disease. This effect may contribute to the incremental mortality benefit compared with clopidogrel.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01894789.

Impact of Diabetes Mellitus on the Pharmacodynamic Effects of Ticagrelor Versus Clopidogrel in Troponin-Negative Acute Coronary Syndrome Patients Undergoing Ad Hoc Percutaneous Coronary Intervention

Background

Diabetes mellitus (DM) is associated with enhanced platelet reactivity and impaired response to oral antiplatelet therapy, including clopidogrel. This post hoc analysis investigated the pharmacodynamic effects of ticagrelor versus clopidogrel loading dose (LD) in troponin‐negative acute coronary syndrome patients with or without DM undergoing percutaneous coronary intervention in the Ad Hoc PCI study.

Methods and Results

Patients randomized (1:1) to receive ticagrelor 180 mg LD or clopidogrel 600 mg LD were assessed by diabetic status. Platelet reactivity (P2Y₁₂ reaction units [PRU] on VerifyNow^® assay) was measured pre‐LD, at 0.5, 2, and 8 hours post‐LD, and at the end of the percutaneous coronary intervention. The primary endpoint was PRU levels 2 hours post‐LD; secondary endpoints included rates of high on‐treatment platelet reactivity (PRU≥208). Of 100 randomized patients, 51 received ticagrelor (DM, n=20; non‐DM, n=31) and 49 clopidogrel (DM, n=16; non‐DM, n=33). At 2 hours post‐LD, mean (SD) PRU levels in DM patients were 130.1 (111.7) with ticagrelor versus 287.6 (71.9) with clopidogrel (mean [95%CI] difference −157.5 [−225.3, −89.8]; P<0.001); in non‐DM patients, they were 75.3 (75.7) versus 243.0 (72.4) (mean difference −167.7 [−207.1, −128.3]; P<0.001). High on‐treatment platelet reactivity rates at 2 hours post‐LD were also significantly (P<0.001) reduced with ticagrelor versus clopidogrel in DM and non‐DM patients. Between‐treatment differences for PRU and high on‐treatment platelet reactivity were not significant at earlier time points but were at 8 hours post‐LD (P<0.001).

Conclusions

Compared with clopidogrel, ticagrelor achieved faster, enhanced platelet inhibition and reduced high on‐treatment platelet reactivity rates, in DM and non‐DM patients.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01603082.

Consistent platelet inhibition with ticagrelor 60 mg twice-daily following myocardial infarction regardless of diabetes status

Diabetes increases cardiovascular risk and reduces pharmacodynamic response to some oral antiplatelet drugs. This study aimed to determine whether ticagrelor 60 mg twice daily (bid) provided potent and consistent platelet inhibition in patients with vs without diabetes in the PEGASUS-TIMI 54 platelet function substudy. Out of 180 patients studied, 58 patients were randomised to and had received at least four weeks of ticagrelor 60 mg bid, with 20 (34 %) having diabetes, 58 patients received ticagrelor 90 mg bid, with 12 (21 %) having diabetes, and 64 patients received placebo, with 18 (28 %) having diabetes. Blood was sampled pre- and 2 hours post-maintenance dose. In patients treated with ticagrelor 60 mg bid, on-treatment platelet reactivity to ADP, as determined by light transmission aggregometry (LTA), VerifyNow and VASP, was similar in patients with vs without diabetes (LTA post-dose, ADP 20 µM: 29 ± 14 vs 34 ± 10 %, respectively; p = 0.19). A consistent inhibitory effect of ticagrelor 60 mg bid was observed pre- and post-dose regardless of diabetes status, even in insulin-treated patients. Patients with diabetes did not have an increased incidence of high platelet reactivity in either ticagrelor group. Platelet reactivity was similar in patients with diabetes treated with ticagrelor 60 mg vs 90 mg bid. Pharmacokinetics of ticagrelor were not affected by diabetes status. In conclusion, ticagrelor 60 mg bid is equally effective at reducing platelet reactivity in patients with and without diabetes, yielding a consistently high level of platelet inhibition regardless of diabetes status.

Pharmacodynamic Comparison of Prasugrel Versus Ticagrelor in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease: The OPTIMUS (Optimizing Antiplatelet Therapy in Diabetes Mellitus)-4 Study

BACKGROUND

Patients with diabetes mellitus (DM) are at increased risk of atherothrombotic events, underscoring the importance of effective platelet inhibiting therapies. Prasugrel and ticagrelor reduce thrombotic complications to a greater extent than clopidogrel. Subgroup analyses of pivotal clinical trials testing prasugrel and ticagrelor versus clopidogrel showed DM patients to have benefits that were consistent with the overall trial populations, although the magnitude of the ischemic risk reduction appeared to be enhanced with prasugrel. Whether these findings may be attributed to differences in the pharmacodynamic profiles of these drugs in DM patients remains poorly explored and represented the aim of this study.

METHODS

In this prospective, randomized, double-blind, double-dummy, crossover pharmacodynamic study, aspirin-treated DM patients (n=50) with coronary artery disease were randomly assigned to receive prasugrel (60 mg loading dose [LD]/10 mg maintenance dose once daily) or ticagrelor (180 mg LD/90 mg maintenance dose twice daily) for 1 week. Pharmacodynamic assessments were conducted using 4 different assays, including VerifyNow P2Y12, vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate, which allowed us to explore ADP- and non-ADP-induced (arachidonic acid-, collagen-, thrombin receptor-activating, peptide-induced) platelet signaling pathways. The acute (baseline, 30 minutes, and 2 hours post-LD) and maintenance (1 week) effects of therapy were assessed. The primary end point of the study was the comparison of P2Y12 reaction units determined by VerifyNow P2Y12 at 1 week between prasugrel and ticagrelor.

RESULTS

ADP- and non-ADP-induced measures of platelet reactivity reduced significantly with both prasugrel and ticagrelor LD and maintenance dose. P2Y12 reaction units defined by VerifyNow were similar between prasugrel and ticagrelor at 30 minutes and 2 hours post-LD. At 1 week, P2Y12 reaction units were significantly lower with ticagrelor than with prasugrel (52 [32-72] versus 83 [63-103]; least-square means difference: -31; 95% confidence interval, -57 to -4; P=0.022; primary end point). Pharmacodynamic assessments measured by vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate were similar between prasugrel and ticagrelor at each time point, including at 1 week. Rates of high on-treatment platelet reactivity were similar between groups with all assays at all time points.

CONCLUSIONS

In DM patients with coronary artery disease, ticagrelor exerts similar or greater inhibition of ADP-induced platelet reactivity in comparison with prasugrel in the acute and chronic phases of treatment, whereas the inhibition of measures of non-ADP-induced platelet reactivity was not significantly different between the 2 agents.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01852214.