Eva C. Jensen

Long-Term Use of Ticagrelor in Patients with Prior Myocardial Infarction.

BACKGROUND The potential benefit of dual antiplatelet therapy beyond 1 year after a myocardial infarction has not been established. We investigated the efficacy and safety of ticagrelor, a P2Y12 receptor antagonist with established efficacy after an acute coronary syndrome, in this context. METHODS We randomly assigned, in a double-blind 1:1:1 fashion, 21,162 patients who had had a myocardial infarction 1 to 3 years earlier to ticagrelor at a dose of 90 mg twice daily, ticagrelor at a dose of 60 mg twice daily, or placebo. All the patients were to receive low-dose aspirin and were followed for a median of 33 months. The primary efficacy end point was the composite of cardiovascular death, myocardial infarction, or stroke. The primary safety end point was Thrombolysis in Myocardial Infarction (TIMI) major bleeding. RESULTS The two ticagrelor doses each reduced, as compared with placebo, the rate of the primary efficacy end point, with Kaplan-Meier rates at 3 years of 7.85% in the group that received 90 mg of ticagrelor twice daily, 7.77% in the group that received 60 mg of ticagrelor twice daily, and 9.04% in the placebo group (hazard ratio for 90 mg of ticagrelor vs. placebo, 0.85; 95% confidence interval [CI], 0.75 to 0.96; P=0.008; hazard ratio for 60 mg of ticagrelor vs. placebo, 0.84; 95% CI, 0.74 to 0.95; P=0.004). Rates of TIMI major bleeding were higher with ticagrelor (2.60% with 90 mg and 2.30% with 60 mg) than with placebo (1.06%) (P<0.001 for each dose vs. placebo); the rates of intracranial hemorrhage or fatal bleeding in the three groups were 0.63%, 0.71%, and 0.60%, respectively. CONCLUSIONS In patients with a myocardial infarction more than 1 year previously, treatment with ticagrelor significantly reduced the risk of cardiovascular death, myocardial infarction, or stroke and increased the risk of major bleeding. (Funded by AstraZeneca; PEGASUS-TIMI 54 ClinicalTrials.gov number, NCT01225562.).

Oral direct thrombin inhibitor AZD0837 for the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation: a randomized dose-guiding, safety, and tolerability study of four doses of AZD0837 vs. vitamin K antagonists

Aims Oral anticoagulation with vitamin K antagonists (VKAs) for stroke prevention in atrial fibrillation (AF) is effective but has significant limitations. AZD0837, a new oral anticoagulant, is a prodrug converted to a selective and reversible direct thrombin inhibitor (AR-H067637). We report from a Phase II randomized, dose-guiding study (NCT00684307) to assess safety, tolerability, pharmacokinetics, and pharmacodynamics of extended-release AZD0837 in patients with AF. Methods and results Atrial fibrillation patients (n = 955) with ≥1 additional risk factor for stroke were randomized to receive AZD0837 (150, 300, or 450 mg once daily or 200 mg twice daily) or VKA (international normalized ratio 2–3, target 2.5) for 3–9 months. Approximately 30% of patients were naïve to VKA treatment. Total bleeding events were similar or lower in all AZD0837 groups (5.3–14.7%, mean exposure 138–145 days) vs. VKA (14.5%, mean exposure 161 days), with fewer clinically relevant bleeding events on AZD0837 150 and 300 mg once daily. Adverse events were similar between treatment groups; with AZD0837, the most common were gastrointestinal disorders (e.g. diarrhoea, flatulence, or nausea). d-Dimer, used as a biomarker of thrombogenesis, decreased in all groups in VKA-naïve subjects with treatment, whereas in VKA pre-treated patients, d-dimer levels started low and remained low in all groups. As expected, only a few strokes or systemic embolic events occurred. In the AZD0837 groups, mean S-creatinine increased by ∼10% from baseline and returned to baseline following treatment cessation. The frequency of serum alanine aminotransferase ≥3× upper limit of normal was similar for AZD0837 and VKA. Conclusion AZD0837 was generally well tolerated at all doses tested. AZD0837 treatment at an exposure corresponding to the 300 mg od dose in this study provides similar suppression of thrombogenesis at a potentially lower bleeding risk compared with dose-adjusted VKA. This study is registered with ClinicalTrials.gov, number NCT00684307.

Design and rationale for the Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin–Thrombolysis in Myocardial Infarction 54 (PEGASUS-TIMI 54) trial

BACKGROUND P2Y12 receptor antagonist therapy is recommended in addition to ASA for up to 1 year after acute coronary syndrome to reduce ischemic events. In contrast, the benefit of long-term dual antiplatelet therapy beyond 1 year remains unclear. Ticagrelor is a potent, reversibly binding P2Y12 receptor-antagonist that has been shown to be superior to clopidogrel in patients with acute coronary syndromes for up to 1 year. STUDY DESIGN PEGASUS-TIMI 54 is a randomized, double-blind, placebo-controlled, multinational clinical trial designed to evaluate the efficacy and safety of ticagrelor in addition to aspirin (75-150 mg) for the prevention of major adverse cardiovascular events in patients with a history of myocardial infarction and risk factors. Patients with a history of spontaneous myocardial infarction within 1 to 3 years are randomized in a 1:1:1 fashion to ticagrelor 90 mg twice daily, ticagrelor 60 mg twice daily, or matching placebo, all with low dose ASA, until the end of the study. The primary endpoint is a composite of cardiovascular death, myocardial infarction, or stroke. Recruitment began in October 2010 and completed in April 2013 with a sample size of over 21,000 patients. The trial is planned to continue until the latest of either 1,360 adjudicated primary end points are accrued or the last patient randomized has been followed for at least 12 months. CONCLUSIONS PEGASUS-TIMI 54 is investigating whether the addition of intensive antiplatelet therapy with ticagrelor to low-dose aspirin reduces major adverse cardiovascular events in high-risk patients with a history of myocardial infarction.

Ischaemic risk and efficacy of ticagrelor in relation to time from P2Y12 inhibitor withdrawal in patients with prior myocardial infarction: insights from PEGASUS-TIMI 54

AIMS Ticagrelor reduced major adverse cardiovascular event (MACE) by 15-16% in patients with prior myocardial infarction (MI) in PEGASUS-TIMI 54. We hypothesized that patients who recently discontinued P2Y12 inhibition, even years after MI, may be at particular risk of MACE and may derive particular benefit from continuation or reinitiation of therapy. METHODS AND RESULTS Patients in PEGASUS-TIMI 54 were categorized by time from last P2Y12 inhibitor (days: ≤30, >30-360, >360). The risk of MACE and the efficacy of ticagrelor were compared across categories. In the placebo arm, patients who more recently stopped P2Y12 inhibitor therapy had a greater number of risk factors but still had a higher risk of MACE after multivariable adjustment [≤30 days, hazard ratio (HR)adj 1.47, 95% confidence interval (CI) 1.12-1.93, P = 0.0051; 30 days-1 year, HRadj 1.28, 95% CI 0.98-1.67, P = 0.073] compared with those who stopped >1 year prior (P-trend = 0.0097). The benefit of ticagrelor depended on the time from last dose, with HRs (95% CI) for ticagrelor (pooled doses) vs. placebo of 0.73 (0.61-0.87), 0.86 (0.71-1.04), and 1.01 (0.80-1.27), respectively, by category (P-trend for interaction < 0.001). The benefit in those ≤30 days of stopping was similar regardless of time from MI (<2 years, HR 0.73, 95% CI 0.60-0.89 vs. ≥2 years, HR 0.71, 95% CI 0.50-1.00). CONCLUSION The benefit of ticagrelor for long-term secondary prevention in patients with prior MI and at least one additional risk factor appeared more marked in patients continuing on or re-starting after only a brief interruption of P2Y12 inhibition, when compared with patients who had proved themselves stable more than 2 years from their MI and off P2Y12 inhibitor therapy for more than a year. The increase in bleeding events with ticagrelor was similar regardless of this time interval. For clinicians considering a strategy of prolonged P2Y12 inhibitor therapy in high-risk patients, these data suggest greater benefit in the continuation of such therapy without interruption after MI, rather than re-initiating such therapy in patients who have remained stable for an extended period. Future analyses may help to clarify further the profile of post-MI patients most likely to benefit from uninterrupted dual antiplatelet therapy. CLINICAL TRIAL REGISTRATION INFORMATION http://www.clinicaltrials.gov NCT01225562.

Safety and tolerability of an immediate-release formulation of theoral direct thrombin inhibitor AZD0837 in the prevention of stroke and systemic embolism in patients with atrial fibrillation

AZD0837 is an investigational oral anticoagulant which is converted to the active form, AR-H067637, a selective direct thrombin inhibitor. The present study, a multicentre, randomised, parallel-group, dose-guiding study, assessed the safety and tolerability of an immediate-release formulation of AZD0837 compared with dose-adjusted warfarin in the prevention of stroke and systemic embolic events in atrial fibrillation (AF) patients. Two hundred fifty AF patients with at least one additional risk factor for stroke were randomised to receive either immediate-release AZD0837 (150mg twice daily [bid] or 350mg bid, blinded treatment) or dose-adjusted warfarin (international normalised ratio 2.0-3.0, open treatment) for three months. The safety and tolerability of 150mg bid AZD0837 appeared to be as good as that of warfarin. Total bleeding events were six with 150mg bid AZD0837, 15 with 350mg bid AZD0837 and eight with warfarin. Alanine aminotransferase elevations (>3xupper limit of normal) were infrequent, without apparent differences between treatment groups. A numerically higher incidence of serious adverse events was observed with 350mg bid AZD0837 compared with 150mg bid, with six of 13 being cardiac related, all with different diagnoses. An increase in mean serum creatinine of approximately 10% was observed in both AZD0837 groups, which returned to baseline after completion of therapy. There were no strokes, transient ischaemic attacks or cerebral haemorrhages with any of the treatments. In conclusion, the safety and tolerability of 150mg bid immediate-release AZD0837 appeared to be as good as that of dose-adjusted warfarin. However, larger studies will be needed to define the safety profile of AZD0837.

Efficacy and safety of ticagrelor for long-term secondary prevention of atherothrombotic events in relation to renal function: insights from the PEGASUS-TIMI 54 trial

AIMS We evaluated the relationship of renal function and ischaemic and bleeding risk as well as the efficacy and safety of ticagrelor in stable patients with prior myocardial infarction (MI). METHODS AND RESULTS Patients with a history of MI 1-3 years prior from PEGASUS-TIMI 54 were stratified based on estimated glomerular filtration rate (eGFR), with <60 mL/min/1.73 m(2) pre-specified for analysis of the effect of ticagrelor on the primary efficacy composite of cardiovascular death, MI, or stroke (major adverse cardiovascular events, MACE) and the primary safety endpoint of TIMI major bleeding. Of 20 898 patients, those with eGFR <60 (N = 4849, 23.2%) had a greater risk of MACE at 3 years relative to those without, which remained significant after multivariable adjustment (hazard ratio, HRadj 1.54, 95% confidence interval, CI 1.27-1.85, P < 0.001). The relative risk reduction in MACE with ticagrelor was similar in those with eGFR <60 (ticagrelor pooled vs. placebo: HR 0.81; 95% CI 0.68-0.96) vs. ≥60 (HR 0.88; 95% CI 0.77-1.00, Pinteraction = 0.44). However, due to the greater absolute risk in the former group, the absolute risk reduction with ticagrelor was higher: 2.7 vs. 0.63%. Bleeding tended to occur more frequently in patients with renal dysfunction. The absolute increase in TIMI major bleeding with ticagrelor was similar in those with and without eGFR <60 (1.19 vs. 1.43%), whereas the excess of minor bleeding tended to be more pronounced (1.93 vs. 0.69%). CONCLUSION In patients with a history of MI, patients with renal dysfunction are at increased risk of MACE and consequently experience a particularly robust absolute risk reduction with long-term treatment with ticagrelor.

Prevention of Stroke with Ticagrelor in Patients with Prior Myocardial Infarction: Insights from PEGASUS-TIMI 54 (Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis in Myocardial Infarction 54).

Background: In the PEGASUS-TIMI 54 trial (Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis in Myocardial Infarction 54), ticagrelor reduced the risk of major adverse cardiovascular events when added to low-dose aspirin in stable patients with prior myocardial infarction, resulting in the approval of ticagrelor 60 mg twice daily for long-term secondary prevention. We investigated the incidence of stroke, outcomes after stroke, and the efficacy of ticagrelor focusing on the approved 60 mg twice daily dose for reducing stroke in this population. Methods: Patients were followed for a median of 33 months. Stroke events were adjudicated by a central committee. Data from similar trials were combined using meta-analysis. Results: Of 14 112 patients randomly assigned to placebo or ticagrelor 60 mg, 213 experienced a stroke; 85% of these strokes were ischemic. A total of 18% of strokes were fatal and another 15% led to either moderate or severe disability at 30 days. Ticagrelor significantly reduced the risk of stroke (hazard ratio, 0.75; 95% confidence interval, 0.57–0.98; P=0.034), driven by a reduction in ischemic stroke (hazard ratio, 0.76; 95% confidence interval, 0.56–1.02). Hemorrhagic stroke occurred in 9 patients on placebo and 8 patients on ticagrelor. A meta-analysis across 4 placebo-controlled trials of more intensive antiplatelet therapy in 44 816 patients with coronary disease confirmed a marked reduction in ischemic stroke (hazard ratio, 0.66; 95% confidence interval, 0.54–0.81; P=0.0001). Conclusions: High-risk patients with prior myocardial infarction are at risk for stroke, approximately one-third of which are fatal or lead to moderate-to-severe disability. The addition of ticagrelor 60 mg twice daily significantly reduced this risk without an excess of hemorrhagic stroke but with more major bleeding. In high-risk patients with coronary disease, more intensive antiplatelet therapy should be considered not only to reduce the risk of coronary events, but also of stroke. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique Identifier: NCT01225562.

Exposure- response for biomarkers of anticoagulant effects by the oral direct thrombin inhibitor AZD0837 in patients with atrial fibrillation.

AIMS AZD0837 is a novel oral anticoagulant investigated in clinical studies for stroke prevention in patients with atrial fibrillation (AF). It is bioconverted to its active form, AR-H067637, a potent, specific and reversible thrombin inhibitor. The effects on coagulation biomarkers were correlated with the pharmacokinetic (PK) exposure of AR-H067637 to guide selection of the effective dose regimen for a confirmatory efficacy study in AF patients. METHODS Blood samples were obtained from 601 AF patients randomized to one of four doses of AZD0837 (blinded treatment) or dose-adjusted vitamin K antagonists (VKA, open treatment) for 3-9 months. A pharmacodynamic model was developed to describe the time course of the AR-H067637 exposure dependent effects and the effect of VKA on fibrin D-dimer. The thrombin generation measured ex vivo in venous plasma was also investigated. RESULTS The PK exposure of AR-H067637 was stable with an interindividual variability of 33% and no or minor influence of patient demographics or comedications. For AZD0837, D-dimer levels decreased with more rapid onset than for VKA. The decrease in D-dimer levels correlated with steady-state plasma concentrations (C(ss)) of AR-H067637, with a maximum decrease of baseline D-dimer levels estimated to approximately 60% for both AZD0837 and VKA therapy. The effect on thrombin generation correlated closely with the plasma concentration of AR-H067637. CONCLUSIONS The effects on thrombin generation and fibrin D-dimer levels correlated with the plasma concentration of its active form and provided comparable effects to well-controlled VKA therapy at an exposure at least corresponding to the 300 mg once daily dose of AZD0837.