vorapaxar and Myocardial-Infarction

Acute Coronary Syndrome (ACS) is a term that describes pathologies related to myocardial ischemia, and is comprised of unstable angina, non-ST elevation myocardial infarction, and ST elevation myocardial infarction. Urgent management of ACS is typically necessary to prevent future morbidity and mortality. Current medical recommendations of ACS management involve use of dual antiplatelet therapy, typically with aspirin and clopidogrel. However, newer therapies are being designed and researched to improve outcomes for patients with ACS. Vorapaxar is a novel antiplatelet therapy that inhibits thrombin-mediated platelet aggregation to prevent recurrence of ischemic events. It has been Food and Drug Administration approved for reduction of thrombotic cardiovascular events in patients with a history of MI or peripheral arterial disease with concomitant use of clopidogrel and/or aspirin, based upon the findings of the TRA 2°P-TIMI 50 trial. However, Vorapaxar was also found to have a significantly increased risk of bleeding, which must be considered when administering this drug. Based upon further subgroup analysis of both the TRA 2°P-TIMI 50 trial and TRACER trial, Vorapaxar was found to be potentially beneficial in patients with peripheral artery disease, coronary artery bypass grafting, and ischemic stroke. There are current trials in progress that are further evaluating the use of Vorapaxar in those conditions, and future research and trials are necessary to fully determine the utility of this drug.

Topics: Acute Coronary Syndrome; Aspirin; Clopidogrel; Humans; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Receptors, Proteinase-Activated; Stroke; Treatment Outcome

In spite of treatment with the current standard of care antiplatelet regimens including dual antiplatelet therapy, recurrence rates of ischemic events remain elevated for high-risk patients with atherosclerotic disease. This may be in part attributed to the fact that other key platelet activation pathways remain uninhibited and can thus continue to trigger platelet activation and lead to thrombotic complications. Thrombin is a powerful inducer of platelet activation and mediates its effects directly on platelets through protease activator receptors (PARs), particularly the PAR-1 subtype, making PAR-1 inhibition an attractive approach for reducing atherothrombotic events. These observations have led to the development of several PAR-1 antagonists. Vorapaxar is a direct inhibitor of PAR-1 and the only agent of this class approved for the prevention of recurrent ischemic events in patients with prior myocardial infarction or peripheral artery disease. In the present manuscript, we present a review of the pathophysiologic role of thrombin on thrombotic complications, the impact of vorapaxar on outcomes, including the most recent updates deriving from clinical trials, as well as future perspectives in the field.

Topics: Atherosclerosis; Humans; Lactones; Myocardial Infarction; Myocardial Ischemia; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Secondary Prevention; Thrombin; Thrombosis

Despite the use of therapies recommended in practice guidelines for secondary prevention in patients with atherosclerotic coronary artery disease, the residual risk for cardiovascular events remains high. Some of the residual risk is believed to result from incomplete platelet inhibition with current therapy. Vorapaxar is a first-in-class, novel antiplatelet agent that acts by antagonizing the PAR-1 receptor, inhibiting thrombin-mediated platelet activation. Vorapaxar was recently approved by the Food and Drug Administration for secondary prevention of cardiovascular events in patients with a history of myocardial infarction or peripheral artery disease who do not have a history of transient ischemic attack or stroke. We review the data from two key phase III cardiovascular outcome trials with vorapaxar: TRACER and TRA 2P-TIMI 50. We will focus on identifying the key patient populations that should be identified for treatment, highlight practical clinical issues when prescribing vorapaxar, and review unanswered questions. Vorapaxar should be considered in patients at high risk for recurrent ischemic events and low risk of bleeding.

Topics: Animals; Blood Platelets; Coronary Artery Disease; Hemorrhage; Humans; Lactones; Myocardial Infarction; Patient Selection; Plaque, Atherosclerotic; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Recurrence; Risk Assessment; Risk Factors; Secondary Prevention; Signal Transduction; Treatment Outcome

To review the pharmacology, efficacy, and safety of vorapaxar, a protease activator receptor-1 (PAR-1) antagonist, in the management of atherosclerotic diseases.. Peer-reviewed clinical trials and review articles were identified from MEDLINE and Current Content database (both 1966 to December 31, 2014) using the search terms vorapaxar and protease activator receptor antagonist.. A total of 30 clinical studies were identified (16 clinical trials, including subanalyses, 14 related to pharmacology, pharmacokinetics, and pharmacodynamics and drug interactions).. Two phase III clinical trials with vorapaxar have been published. In patients with non-ST segment elevation myocardial infarction (MI), vorapaxar failed to significantly reduce the primary efficacy end point (composite of cardiovascular death, MI, stroke, recurrent ischemia with hospitalization, and urgent coronary revascularization). Conversely, in a study of secondary prevention for patients with cardiovascular disease, the composite end point of cardiovascular death, MI, or stroke was significantly reduced. In both trials, the safety end points of major/minor bleeding were increased compared with placebo. In the secondary prevention trial, an increased incidence of intracranial hemorrhage led to the exclusion of patients with a prior history of stroke.. Vorapaxar is approved for use with aspirin and/or clopidogrel in the secondary prevention of cardiovascular events in stable patients with peripheral arterial disease or a history of MI. However, the addition of vorapaxar to other antiplatelets can significantly increase the risk of bleeding. It is, therefore, essential to balance the need for further reduction of risk of thrombotic event with patient's individual bleeding risk.

Topics: Atherosclerosis; Cardiovascular Diseases; Clinical Trials, Phase III as Topic; Hemorrhage; Humans; Lactones; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Risk; Secondary Prevention; Stroke; Treatment Outcome

Antiplatelet therapies play a central role in reducing the risk of cardiovascular events such as myocardial infarction and stroke. While aspirin, a cyclo-oxygenase-1 inhibitor has been the cornerstone of antithrombotic treatment for several decades, P2Y12 receptor inhibitors cangrelor, clopidogrel, prasugrel, and ticagrelor and protease-activated receptor-1 antagonist vorapaxar, have emerged as additional therapies to reduce the risk of recurrent cardiovascular events in high-risk patients. Recent clinical trials evaluating the role of these agents and major society guideline updates for use of antiplatelet therapies for secondary prevention of cardiovascular events will be examined. The latest studies regarding the appropriate duration of dual antiplatelet therapy after percutaneous coronary intervention will be presented. The current state of genetic and platelet function testing will be reviewed.

Topics: Genetic Testing; Humans; Lactones; Myocardial Infarction; Platelet Aggregation Inhibitors; Purinergic P2Y Receptor Antagonists; Pyridines; Receptors, Purinergic P2Y12; Stroke

Atherothrombosis and its clinical manifestations are among the leading causes of death in the developed world. The current standard-of-care antiplatelet therapy for the treatment of such events comprises aspirin and a thienopyridine or ticagrelor. However, recurrent ischemic events due to residual cardiovascular risk are a common phenomenon in these patients. It is believed that this residual risk is caused, at least in part, by thrombin, which signals through protease-activated receptors (PARs) and especially PAR-1. Thus, PAR-1 antagonism could represent an effective approach in the treatment of atherothrombotic disease. In this context, two potent and selective agents have been developed, vorapaxar and atopaxar. However, only vorapaxar has completed phase 3 clinical trials. In the present review, the main pharmacodynamic and pharmacokinetic properties of the PAR-1 antagonists are briefly described and the latest clinical data on vorapaxar are presented.

Topics: Clinical Trials as Topic; Coronary Artery Bypass; Drug Therapy, Combination; Hemorrhage; Humans; Imines; Lactones; Myocardial Infarction; Percutaneous Coronary Intervention; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Receptors, Thrombin; Stents; Stroke; Thrombosis

Vorapaxar (Zontivity®) is a first-in-class, potent and orally-active protease-activated receptor 1 (PAR-1) antagonist that blocks thrombin-mediated platelet activation without interfering with thrombin-mediated fibrin deposition. The long-term efficacy of once-daily vorapaxar added to standard antiplatelet therapy (aspirin with or without clopidogrel) in the secondary prevention of atherothrombotic events in patients with a history of myocardial infarction (MI), ischaemic stroke or peripheral arterial disease was investigated in the large, multinational TRA 2°P-TIMI 50 trial. Compared with placebo, vorapaxar significantly reduced the risk of the composite endpoints of cardiovascular (CV) death, MI or stroke, and CV death, MI, stroke or urgent coronary revascularization in the overall trial population. Vorapaxar also significantly reduced the risk of these composite endpoints in the subgroup of patients with prior MI (the largest qualifying disease cohort) and the subset of post-MI patients with no history of stroke or transient ischaemic attack (TIA). Vorapaxar significantly increased the risk of GUSTO moderate and/or severe bleeding in the overall trial population and all key subgroups (including post-MI patients with no history of stroke or TIA). Vorapaxar also significantly increased the risk of intracranial haemorrhage (ICH) in the overall trial population and the subgroup of patients with prior stroke, but not the subgroup of post-MI patients or the subset of post-MI patients with no history of stroke or TIA. Based on these results, vorapaxar has been approved in the EU as an adjunctive treatment for the secondary prevention of atherothrombotic events in patients with prior MI who do not have a history of stroke, TIA or ICH.

Topics: Clinical Trials as Topic; Humans; Lactones; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Secondary Prevention; Stroke; Thrombosis

Acute myocardial infarction (AMI) is generally attributed to coronary atherothrombotic disease. Platelet activation is essential for thrombus formation and is thus an important target for pharmacological intervention to prevent and treat AMI. Despite contemporary treatment with dual antiplatelet therapy, including acetylsalicylic acid and adenosine diphosphate receptor antagonists, patients with prior AMI remain at increased risk of future thrombotic events. This has stimulated the search for more potent antithrombotic agents. Among these is the oral protease-activated receptor-1 antagonist vorapaxar, which represents a new oral antiplatelet agent to reduce thrombotic risk in patients with atherothrombotic disease. The TRACER and the TRA 2°P-TIMI 50 trials concluded that vorapaxar in addition to standard therapy reduced ischemic adverse cardiac events. A remarkable benefit was observed in patients with stable atherosclerotic disease, particularly those with a previous history of AMI. Although favorable effects were seen in reduction of adverse cardiac events, this was associated with excess major and intracranial bleeding, particularly in patients at high risk of bleeding and those with a history of stroke or transient ischemic attack. Currently, the lack of a reliable individualized risk stratification tool to assess patients for thrombotic and bleeding tendencies in order to identify those who might gain most net clinical benefit has led to limited use of vorapaxar in clinical practice. Vorapaxar may find a niche as an adjunct to standard care in patients at high risk of thrombotic events and who are at low risk of bleeding.

Topics: Animals; Hemorrhage; Humans; Lactones; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Thrombosis

The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, dosage and administration, cost, and place in therapy of vorapaxar in the secondary prevention of atherosclerotic events are reviewed.. Vorapaxar is a highly selective, reversible antagonist of protease-activated receptor-1 expressed on platelets. Vorapaxar competitively inhibits thrombin from activating the receptor, thereby decreasing platelet aggregation. Vorapaxar is rapidly absorbed and distributed, with peak plasma levels being reached within 60-90 minutes. Vorapaxar's effective half-life is three to four days and its terminal elimination half-life is eight days. Vorapaxar sulfate 2.5 mg (equivalent to 2.08 mg of vorapaxar) orally daily without a loading dose was clinically effective for the secondary prevention of ischemic events in patients with a history of myocardial infarction (MI) or with peripheral arterial disease (PAD) without a history of stroke. Phase II and III trials of vorapaxar given with aspirin or a thienopyridine or both demonstrated a reduction in the primary endpoint of cardiovascular death, MI, and stroke in patients with a history of MI or coronary artery disease and PAD. Patients with a history of stroke were found to have an increased rate of intracranial hemorrhage (ICH), which led to a boxed warning placed on vorapaxar's labeling to warn of the increased risk for bleeding in patients with a history of stroke.. Vorapaxar is a novel antiplatelet agent that has demonstrated efficacy in reducing atherosclerotic events in patients with a history of MI or PAD without a history of stroke, transient ischemic attack, or ICH when taken in combination with aspirin and clopidogrel.

Topics: Aspirin; Clopidogrel; Drug Interactions; Drug Therapy, Combination; Half-Life; Hemorrhage; Humans; Lactones; Myocardial Infarction; Myocardial Ischemia; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Receptor, PAR-1; Secondary Prevention; Stroke; Thrombosis; Ticlopidine

Platelet activation with subsequent aggregation is a complex process leading to thrombus formation, which remains a key component for atherothrombotic manifestations, in particular myocardial infarction. Therefore, antiplatelet therapies are pivotal for the treatment of these patients. Current oral antiplatelet therapies used for secondary prevention of ischemic recurrences include aspirin and adenosine diphosphate P2Y12 platelet-receptor antagonists. However, despite these therapies, patients who have experienced a myocardial infarction remain at risk for ischemic recurrences. Therefore, more aggressive secondary prevention measures have been an area of research, including identifying additional targets modulating platelet-activation and -aggregation processes. Among these, thrombin-mediated platelet activation via protease-activated receptors (PARs) has been subject to extensive clinical investigation. Several PAR-1 receptor antagonists have been developed. However, vorapaxar is the only one that has completed large-scale clinical investigation. The present manuscript will provide an overview on the role of thrombin-mediated signaling, the impact of PAR-1 blockade with vorapaxar on ischemic and bleeding outcomes, and the potential role for vorapaxar in clinical practice.

Topics: Animals; Blood Platelets; Hemorrhage; Humans; Lactones; Molecular Targeted Therapy; Myocardial Infarction; Platelet Aggregation; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Risk Factors; Secondary Prevention; Signal Transduction; Treatment Outcome

Vorapaxar [Zontivity(®) (US)], an orally active protease-activated receptor-1 (PAR-1) receptor antagonist, has been developed by Merck & Co for the reduction of thrombotic cardiovascular events in patients with a history of myocardial infarction (MI) or peripheral arterial disease (PAD). Vorapaxar has received its first global approval for this indication in the US. This article summarizes the milestones in the development of vorapaxar leading to this first approval for the reduction of thrombotic cardiovascular events in patients with a prior MI or PAD.

Topics: Drug Approval; Humans; Lactones; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1

Ischemic heart disease remains the number one cause of death in the world despite advances in invasive and pharmacologic therapies. An ongoing area of research is the central role of platelets in atherothrombosis. Many therapeutic strategies have been developed over the last few decades affecting different platelet receptors to alter platelet-mediated thrombosis including targeting the receptors for thromboxane A(2), adenosine diphosphate, and fibrinogen. However, despite the use of pharmacologic agents directed at these pathways, residual morbidity and mortality still exist. Therefore, identifying agents that more favorably balance a reduction in ischemic events while minimizing bleeding events is an ongoing mission. Thrombin is known to be the most potent stimulant of platelet-mediated thrombosis whose action on the platelet is through a family of receptors known as the protease-activated receptors (PARs). Activation through the PAR-1 receptor, in particular, results in an early and intense response by the platelet to thrombin, and it is the primary thrombin receptor on platelets, thus making it a potentially desirable target for therapy. Most recently, two PAR-1 antagonists, atopaxar and vorapaxar, have been tested in clinical trials. Generally, the results show a reduction in ischemic event rates, but an increase in bleeding event rates. This article will summarize the current state of the literature and consider the role these drugs might play in the future for the prevention of ischemic heart disease events.

Topics: Acute Coronary Syndrome; Blood Platelets; Coronary Artery Disease; Hemorrhage; Humans; Imines; Lactones; Myocardial Infarction; Platelet Activation; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Thrombin; Treatment Outcome

Thrombin receptor antagonists blocking protease-activated receptor-1 (PAR-1) on platelets represent a new class of oral antiplatelet agents for patients with atherothrombotic disease manifestations.. We investigated the safety and efficacy of PAR-1 antagonists in patients with coronary artery disease (CAD).. Randomized, placebo-controlled trials of the PAR-1 antagonists atopaxar or vorapaxar in CAD patients were identified. The primary safety endpoint was the composite of Thrombolysis In Myocardial Infarction (TIMI) clinically significant bleeding. The primary efficacy endpoint was the composite of death, myocardial infarction (MI) or stroke.. A total of 41 647 patients from eight trials were included. PAR-1 antagonists were associated with higher risks of TIMI clinically significant (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.39-1.57, P < 0.001), major (OR 1.46, 95% CI 1.28-1.67, P < 0.001) and minor (OR 1.67, 95% CI 1.40-2.00, P < 0.001) bleeding than placebo in the fixed-effects model. PAR-1 antagonists reduced the composite of death, MI or stroke as compared with placebo (OR 0.87, 95% CI 0.81-0.92, P < 0.001), driven by a lower risk of MI (OR 0.85, 95% CI 0.78-0.92, P < 0.001). Conversely, PAR-1 antagonists and placebo did not differ in terms of risk of death (OR 0.99, 95% CI 0.90-1.09, P = 0.81) or stroke (OR 0.96, 95% CI 0.84-1.10, P = 0.59).. PAR-1 antagonists decrease ischemic events in patients with CAD as compared with placebo, mainly driven by a reduction in MI, at the cost of an increased risk of clinically significant bleeding.

Topics: Blood Platelets; Chi-Square Distribution; Coronary Artery Disease; Evidence-Based Medicine; Hemorrhage; Humans; Imines; Lactones; Myocardial Infarction; Odds Ratio; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Receptor, PAR-1; Risk Assessment; Risk Factors; Stroke; Treatment Outcome

Platelet activation and thrombin formation play significant roles in the pathophysiology of acute coronary syndrome. To overcome this pathophysiology, antiplatelet agents are utilized to decrease platelet aggregation and anticoagulants to decrease thrombin formation. Current antiplatelet agents are designed to inhibit various mediators of platelet activation, such as thromboxane A2 and adenosine diphosphate, and platelet-surface receptors (e.g., glycoprotein IIb/IIIa receptors). The rationale for upstream versus deferred administration of antiplatelet therapy in patients scheduled for percutaneous intervention and the current ACC/AHA guidelines for the management of patients with unstable angina/non-ST-segment myocardial infarction are discussed. The next-generation antiplatelet drugs are in various stages of clinical development, with unique differentiating mechanistic and pharmacokinetic properties. The newer P2Y12 thienopyridine receptor antagonists and protease receptor inhibitor are also examined, in addition to the rationale of various outcome studies evaluating the efficacy and safety of the different agents.

Topics: Acute Coronary Syndrome; Adenosine Monophosphate; Angina, Unstable; Aspirin; Blood Platelets; Cardiac Catheterization; Fibrinolytic Agents; Humans; Lactones; Myocardial Infarction; Platelet Activation; Platelet Aggregation Inhibitors; Practice Guidelines as Topic; Pyridines; Treatment Outcome

Risk stratification of patients with recent myocardial infarction (MI) for subsequent cardiovascular (CV) events helps identify patients most likely to benefit from secondary prevention therapies. This study externally validated a new risk score (TRS2˚P) for secondary events derived from the TRA2°P-TIMI 50 trial among post-MI patients from two large health care systems.. This retrospective cohort study included 9618 patients treated for acute MI at either the Cleveland Clinic (CC) or Geisinger Health System (GHS) between 2008 and 2013. Patients with a clinic visit within 2-52 weeks of MI were included and followed for CV death, repeat MI, and ischemic stroke through electronic medical records (EMR). The TRS2˚P is based on nine factors determined through EMR documentation. Discrimination and calibration of the TRS2˚P were quantified in both patient populations.. MI patients at CC and GHS were older, had more comorbidities, received fewer medications, and had higher 3-year event rates compared to subjects in the TRA2°P trial: 31% (CC), 33% (GHS), and 10% (TRA2°P-TIMI 50). The proposed risk score had similar discrimination across the three cohorts with c-statistics of 0.66 (CC), 0.66 (GHS), and 0.67 (TRA2°P-TIMI 50). A strong graded relationship between the risk score and event rates was observed in all cohorts, though 3-year event rates were consistently higher within TRS2°P strata in the CC and GHS cohorts relative to TRA2˚P-TIMI 50.. The TRS2˚P demonstrated consistent risk discrimination across trial and non-trial patients with recent MI, but event rates were consistently higher in the non-trial cohorts.

Topics: Aged; Calibration; Cardiovascular Diseases; Double-Blind Method; Electronic Health Records; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Reproducibility of Results; Retrospective Studies; Risk Assessment; Secondary Prevention; Severity of Illness Index; Stroke

Vorapaxar is a first-in-class protease-activated receptor-1 antagonist indicated for the reduction of cardiovascular death, myocardial infarction, and stroke in stable patients with prior atherothrombosis, who have not had a prior stroke or transient ischemic attack. The aims of this study were to investigate: 1) the role of vorapaxar in patients with severe coronary artery disease treated previously with coronary artery bypass grafting (CABG); and 2) safety in patients undergoing CABG while receiving vorapaxar.. TRA 2°P-TIMI 50 was a randomized, double-blinded, placebo-controlled trial of vorapaxar in 26,449 stable patients with prior atherothrombosis followed for a median of 30 months. We 1) investigated the efficacy of vorapaxar among patients with a history of CABG prior to randomization ( n=2942); and 2) assessed the safety among 367 patients who underwent a new CABG during the trial.. Patients with a prior CABG were at higher risk for cardiovascular death, myocardial infarction, or stroke at three years compared with patients without a prior CABG (13.7% vs. 7.8%, p<0.001). Among patients with a prior CABG, vorapaxar significantly reduced the risk of cardiovascular death, myocardial infarction, or stroke (11.9% vs. 15.6%, hazard ratio 0.71, 95% confidence interval 0.58-0.88, p=0.001; number-needed-to-treat = 27). In patients undergoing CABG while receiving vorapaxar, the rate of Thrombolysis in Myocardial Infarction CABG major bleeding was 6.3% vs. 4.1% with placebo (hazard ratio 1.53, 95% confidence interval 0.58-4.01, p=0.39).. In patients with a prior CABG, vorapaxar significantly reduced the risk of recurrent major cardiovascular events. In patients undergoing CABG while receiving vorapaxar, bleeding risk appeared similar to that seen in the overall trial population.

Topics: Aged; Coronary Artery Bypass; Double-Blind Method; Female; Heart Diseases; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Secondary Prevention; Stroke; Thrombosis; Treatment Outcome

Cardiac troponin I, measured with a high-sensitivity assay (hs-TnI), is well-established for risk prediction in acute coronary syndromes. However, its prognostic role in stable atherosclerotic disease, particularly for future myocardial infarction (MI), is less well defined.. We measured hs-TnI (Abbott ARCHITECT) in 15833 patients with prior MI, ischemic stroke, or peripheral arterial disease from the placebo-controlled Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events (TRA 2°P)-Thrombolysis in Myocardial Infarction (TIMI) 50 trial of the platelet inhibitor vorapaxar, excluding patients with recent MI (<30 days). hs-TnI was categorized into 5 groups based on the detection limit (1.9 ng/L), 99th percentile reference limit (26 ng/L), and tertiles in between (1.9-26 ng/L), as well as sex-specific reference limits.. Higher hs-TnI concentration was associated with older age, male sex, and increased atherosclerosis burden. hs-TnI identified a graded 3-year risk of cardiovascular death, MI, or stroke from 5.0% to 18.6% (P < 0.001), driven by cardiovascular death and MI (P < 0.001). This risk was independent of established clinical risk indicators, B-type natriuretic peptide and C-reactive protein [adjusted hazard ratio 2.70 (95% CI, 1.96-3.71), P < 0.001 for hs-TnI >26 ng/L vs <1.9 ng/L]. In patients with prior MI, there was a pattern of greater absolute benefit with vorapaxar in patients with an increased hs-TnI (absolute risk difference 1.9% with hs-TnI >26 ng/L vs 0.3% with hs-TnI <1.9 ng/L; P interaction = 0.82).. In stable patients with established atherosclerosis, hs-TnI concentrations effectively stratified the risk of new or recurrent cardiovascular (CV) events, in particular CV death and MI. High-risk patients with prior MI identified by increased hs-TnI had a substantial absolute improvement in net clinical outcome with vorapaxar.

Topics: Aged; Biomarkers; Double-Blind Method; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Troponin I

We evaluated outcomes associated with transradial vs. transfemoral approaches and vorapaxar in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) in the TRACER trial.. Vorapaxar reduces ischemic events but increases the risk of major bleeding.. We compared 30-day and 2-year major adverse cardiac events (MACE: cardiovascular death, myocardial infarction, stroke, recurrent ischemia with rehospitalization, and urgent coronary revascularization) and noncoronary artery bypass graft (CABG)-related bleedings in 2,192 transradial and 4,880 transfemoral patients undergoing PCI after adjusting for confounding variables, including propensity for transradial access.. Overall, 30-day GUSTO moderate/severe and non-CABG TIMI major/minor bleeding occurred less frequently in transradial (0.9% vs. 2.0%, P = 0.001) vs. transfemoral (1.1% vs. 2.5%, P = 0.005) patients. A similar reduction was seen at 2 years (3.3% vs. 4.7%, P = 0.008; 3.3% vs. 4.9%, P < 0.001, respectively). Transradial was associated with an increased risk of ischemic events at 30 days (OR 1.38, 95% CI 1.11-1.72; P = 0.004), driven primarily by increased periprocedural myocardial infarctions. At 2 years, rates of MACE were comparable (HR 1.14, 95% CI 0.98-1.33; P = 0.096). Although bleeding rates were higher with vorapaxar in transfemoral vs. transradial patients, there was no significant treatment interaction. Also, the access site did not modulate the association between vorapaxar and MACE.. Transradial access was associated with lower bleeding rates and similar long-term ischemic outcomes, suggesting transradial access is safer than transfemoral access among ACS patients receiving potent antiplatelet therapies. Because of the nonrandomized allocation of arterial access, these results should be considered exploratory. © 2015 Wiley Periodicals, Inc.

Topics: Acute Coronary Syndrome; Aged; Catheterization, Peripheral; Female; Femoral Artery; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Patient Readmission; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Punctures; Pyridines; Radial Artery; Recurrence; Retreatment; Risk Factors; Stroke; Time Factors; Treatment Outcome

Patients with peripheral artery disease (PAD) are at heightened risk of acute limb ischemia (ALI), a morbid event that may result in limb loss. We investigated the causes, sequelae, and predictors of ALI in a contemporary population with symptomatic PAD and whether protease-activated receptor 1 antagonism with vorapaxar reduced ALI overall and by type.. The Trial to Assess the Effects of Vorapaxar in Preventing Heart Attack and Stroke in Patients With Atherosclerosis-Thrombolysis in Myocardial Infarction 50 (TRA2°P-TIMI 50) was a randomized, double-blind, placebo-controlled trial of vorapaxar in stable patients, including 3787 with symptomatic PAD. ALI was a prespecified adjudicated end point using a formal definition. A total of 150 ALI events occurred in 108 patients during follow-up (placebo 3-year rate, 3.9%; 1.3% annualized). For patients with symptomatic PAD, previous peripheral revascularization, smoking, and the ankle-brachial index were predictive of ALI. The majority of ALI events occurred as a result of surgical graft thrombosis (56%), followed by native vessel in situ thrombosis (27%). Stent thrombosis and thromboembolism caused ALI in 13% and 5%, respectively. Amputation occurred in 17.6% presenting with ALI. Vorapaxar reduced first ALI events by 41% (hazard ratio, 0.58; 95% confidence interval, 0.39-0.86; P=0.006) and total ALI events by 41% (94 versus 56 events; risk ratio, 0.59; 95% confidence interval, 0.38-0.93; P=0.022). The efficacy of vorapaxar was consistent across types of ALI.. In selected patients with symptomatic PAD and without atrial fibrillation, ALI occurs at a rate of 1.3%/y, is most frequently caused by acute bypass graft thrombosis or in situ thrombosis of a diseased vessel, and often results in limb loss. Vorapaxar reduces ALI in patients with symptomatic PAD with consistency across type, including PAD resulting from surgical graft thrombosis and in-situ thrombosis.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Acute Disease; Aged; Atherosclerosis; Coronary Artery Bypass; Double-Blind Method; Extremities; Female; Follow-Up Studies; Humans; Ischemia; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Prospective Studies; Pyridines; Stroke; Thrombolytic Therapy; Treatment Outcome

Vorapaxar is a first-in-class protease-activated receptor-1 antagonist indicated for secondary prevention in stable patients with previous myocardial infarction (MI) or peripheral artery disease and no cerebrovascular disease. Vorapaxar is not recommended for initiation in the acute phase of acute coronary syndromes (ACS) because of an unfavorable balance between bleeding and efficacy when started in that setting. The aim of this analysis was to investigate outcomes in patients who experienced a new ACS while receiving vorapaxar for long-term secondary prevention. Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic ischemic Events-Thrombolysis In Myocardial Infarction 50 was a randomized, double-blind, placebo-controlled trial of vorapaxar (n = 26,449). We evaluated bleeding and ischemic events during the acute care of patients with a new ACS during the trial. During a median follow-up of 30 months, 799 patients (8.9%) randomized to vorapaxar and 913 (10.0%) to placebo had a new ACS event (p = 0.003); 87% and 86%, respectively, were on study therapy at the time of the event. In a landmark analysis through 7 days after ACS, the rates of Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) severe bleeding were 0.8% versus 0.8% (hazard ratio [HR] 0.99, 95% CI 0.33 to 2.94) and GUSTO moderate/severe bleeding were 2.5% versus 1.6% (HR 1.59, 95% CI 0.78 to 3.24) with vorapaxar versus placebo. The effect of vorapaxar on cardiovascular death, MI, or stroke (2.4% vs 4.4%; HR 0.54, 95% CI 0.31 to 0.93; p = 0.027) was consistent with the overall trial result. In conclusion, in patients who experience a new ACS event while receiving vorapaxar for secondary prevention, continuing therapy was associated with favorable efficacy without excess severe bleeding during the period of acute ACS management.

Topics: Acute Coronary Syndrome; Aged; Double-Blind Method; Female; Fibrinolytic Agents; Follow-Up Studies; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Secondary Prevention; Treatment Outcome

The Bleeding Academic Research Consortium (BARC) scale has been proposed to standardize bleeding endpoint definitions and reporting in cardiovascular trials. Validation in large cohorts of patients is needed.. This study sought to investigate the relationship between BARC-classified bleeding and mortality and compared its prognostic value against 2 validated bleeding scales: TIMI (Thrombolysis In Myocardial Infarction) and GUSTO (Global Use of Strategies to Open Occluded Arteries).. We analyzed bleeding in 12,944 patients with acute coronary syndromes without ST-segment elevation, with or without early invasive strategy. The main outcome measure was all-cause death.. During follow-up (median: 502 days), noncoronary artery bypass graft (CABG) bleeding occurred in 1,998 (15.4%) patients according to BARC (grades 2, 3, or 5), 484 (3.7%) patients according to TIMI minor/major, and 514 (4.0%) patients according to GUSTO moderate/severe criteria. CABG-related bleeding (BARC 4) occurred in 155 (1.2%) patients. Patients with BARC (2, 3, or 4) bleeding had a significant increase in risk of death versus patients without bleeding (BARC 0 or 1); the hazard was highest in the 30 days after bleeding (hazard ratio: 7.35; 95% confidence interval: 5.59 to 9.68; p < 0.0001) and remained significant up to 1 year. The hazard of mortality increased progressively with non-CABG BARC grades. BARC 4 bleeds were significantly associated with mortality within 30 days (hazard ratio: 10.05; 95% confidence interval: 5.41 to 18.69; p < 0.0001), but not thereafter. Inclusion of BARC (2, 3, or 4) bleeding in the 1-year mortality model with baseline characteristics improved it to an extent comparable to TIMI minor/major and GUSTO moderate/severe bleeding.. In patients with acute coronary syndromes without ST-segment elevation, bleeding assessed with the BARC scale was significantly associated with risk of subsequent death up to 1 year after the event and risk of mortality increased gradually with higher BARC grades. Our results support adoption of the BARC bleeding scale in ACS clinical trials. (Trial to Assess the Effects of Vorapaxar [SCH 530348; MK-5348] in Preventing Heart Attack and Stroke in Participants With Acute Coronary Syndrome [TRACER] [Study P04736]; NCT00527943).

Topics: Acute Coronary Syndrome; Aged; Coronary Artery Bypass; Double-Blind Method; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Prognosis; Pyridines; Risk Assessment; Severity of Illness Index; Stents; Stroke

Patients with stable ischemic heart disease and previous myocardial infarction (MI) vary in their risk for recurrent cardiovascular events. Atherothrombotic risk assessment may be useful to identify high-risk patients who have the greatest potential to benefit from more intensive secondary preventive therapy such as treatment with vorapaxar.. We identified independent clinical indicators of atherothrombotic risk among 8598 stable, placebo-treated patients with a previous MI followed up for 2.5 years (median) in TRA 2°P-TIMI 50 [Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-TIMI 50]. The efficacy and safety of vorapaxar (SCH 530348; MK-5348) were assessed by baseline risk among patients with previous MI without prior stroke or transient ischemic attack for whom there is a clinical indication for vorapaxar. End points were cardiovascular death, MI, or ischemic stroke and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) severe bleeding.. The 9 independent risk predictors were age, diabetes mellitus, hypertension, smoking, peripheral arterial disease, previous stroke, previous coronary bypass grafting, heart failure, and renal dysfunction. A simple integer-based scheme using these predictors showed a strong graded relationship with the rate of cardiovascular death/MI/ischemic stroke and the individual components (P for trend <0.001 for all). High-risk patients (≥3 risk indicators; 20% of population) had a 3.2% absolute risk reduction in cardiovascular disease/MI/ischemic stroke with vorapaxar, and intermediate-risk patients (1-2 risk indicators; 61%) had a 2.1% absolute risk reduction (P<0.001 each), translating to a number needed to treat of 31 and 48. Bleeding increased across risk groups (P for trend<0.01); however, net clinical outcome was increasingly favorable with vorapaxar across risk groups. Fatal bleeding or intracranial hemorrhage was 0.9% with both treatments in high-risk patients.. Stratification of baseline atherothrombotic risk can assist with therapeutic decision making for vorapaxar use for secondary prevention after MI.. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Aged; Atherosclerosis; Double-Blind Method; Female; Hemorrhage; Humans; Kaplan-Meier Estimate; Lactones; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Platelet Aggregation Inhibitors; Proportional Hazards Models; Pyridines; Recurrence; Risk Assessment; Secondary Prevention; Treatment Outcome

Vorapaxar reduces cardiovascular death, myocardial infarction (MI), or stroke in patients with previous MI while increasing bleeding. Patients with diabetes mellitus (DM) are at high risk of recurrent thrombotic events despite standard therapy and may derive particular benefit from antithrombotic therapies. The Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-TIMI 50 trial was a randomized, double-blind, placebo-controlled trial of vorapaxar in patients with stable atherosclerosis.. We examined the efficacy of vorapaxar in patients with and without DM who qualified for the trial with a previous MI. Because vorapaxar is contraindicated in patients with a history of stroke or transient ischemic attack, the analysis (n=16 896) excluded such patients. The primary end point of cardiovascular death, MI, or stroke occurred more frequently in patients with DM than in patients without DM (rates in placebo group: 14.3% versus 7.6%; adjusted hazard ratio, 1.47; P<0.001). In patients with DM (n=3623), vorapaxar significantly reduced the primary end point (11.4% versus 14.3%; hazard ratio, 0.73 [95% confidence interval, 0.60-0.89]; P=0.002) with a number needed to treat to avoid 1 major cardiovascular event of 29. The incidence of moderate/severe bleeding was increased with vorapaxar in patients with DM (4.4% versus 2.6%; hazard ratio, 1.60 [95% confidence interval, 1.07-2.40]). However, net clinical outcome integrating these 2 end points (efficacy and safety) was improved with vorapaxar (hazard ratio, 0.79 [95% confidence interval, 0.67-0.93]).. In patients with previous MI and DM, the addition of vorapaxar to standard therapy significantly reduced the risk of major vascular events with greater potential for absolute benefit in this group at high risk of recurrent ischemic events.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Aged; Death; Diabetes Mellitus; Double-Blind Method; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Receptors, Thrombin; Secondary Prevention; Stroke; Thrombosis; Treatment Outcome

Vorapaxar is a protease-activated receptor-1 antagonist approved by the U.S. Food and Drug Administration (FDA) for the reduction of thrombotic cardiovascular (CV) events in patients with a history of myocardial infarction (MI) and peripheral artery disease (PAD), without a previous stroke or transient ischemic attack (TIA).. We examined the efficacy and safety of vorapaxar in the intended use population, considering 20,170 patients randomized in the multinational, double-blinded, placebo-controlled TRA 2°P-TIMI 50 trial. Of these, 16,897 qualified with a history of MI in the prior 2 weeks to 1 year and 3273 with PAD. At baseline 97% of the patients were treated with aspirin, 71% with a thienopyridine, and 93% a statin. At 3 years, the endpoint of CV death, MI, or stroke was significantly reduced with vorapaxar compared with placebo (7.9% versus 9.5%, HR, 0.80; 95% CI 0.73 to 0.89; P<0.001). Vorapaxar also significantly reduced the composite of CV death, MI, stroke, and urgent coronary revascularization (10.1% versus 11.8%, HR, 0.83; 95% CI 0.76 to 0.90; P<0.001), as well as the rate of CV death or MI (P<0.001). The safety endpoint of GUSTO moderate or severe bleeding, was increased in the vorapaxar group (3.7 versus 2.4, HR, 1.55; 95% CI 1.30 to 1.86, P<0.001). Intracranial bleeding (ICH) was 0.6% versus 0.4%, P=0.10 with vorapaxar versus placebo, with fatal bleeding 0.2% versus 0.2%; P=0.70.. In patients with prior MI or PAD who have not had a previous stroke or TIA, vorapaxar added to standard therapy is effective for long-term secondary prevention of thrombotic CV events, while increasing moderate or severe bleeding.. URL: clinicaltrials.gov Unique Identifier: NCT00526474.

Topics: Aged; Double-Blind Method; Drug Approval; Female; Hemorrhage; Humans; Ischemic Attack, Transient; Kaplan-Meier Estimate; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Recurrence; Risk Factors; Secondary Prevention; Stroke; Time Factors; Treatment Outcome; United States; United States Food and Drug Administration

Vorapaxar antagonizes protease-activated receptor 1, the primary receptor for thrombin on human platelets, and reduces recurrent thrombotic events in stable patients with a previous myocardial infarction (MI). We wished to determine whether the efficacy and safety of antiplatelet therapy with vorapaxar was modified by concurrent thienopyridine use.. The Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-Thrombolysis in Myocardial Infarction 50 (TRA 2°P-TIMI 50) was a randomized, double-blind, placebo-controlled trial of vorapaxar in 26,449 patients with previous atherothrombosis. This prespecified analysis included 16,897 patients who qualified with a MI in the preceding 2 weeks to 12 months and was restricted to patients without a history of stroke or transient ischemic attack given its contraindication in that population. Randomization was stratified on the basis of planned thienopyridine use. Thienopyridine was planned at randomization in 12,410 (73%). Vorapaxar significantly reduced the composite of cardiovascular death, MI, and stroke in comparison with placebo regardless of planned thienopyridine therapy (planned thienopyridine, hazard ratio, 0.80, 0.70-0.91, P<0.001; no planned thienopyridine, hazard ratio, 0.75; 0.60-0.94, P=0.011; P-interaction=0.67). Findings were similar when patients were stratified by actual thienopyridine use at baseline (P-interaction=0.82) and through 18 months (P-interaction=0.44). Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) moderate or severe bleeding risk was increased with vorapaxar and was not significantly altered by planned thienopyridine (planned, hazard ratio, 1.50; 1.18-1.89, P<0.001; no planned, hazard ratio, 1.90, 1.17-3.07, P=0.009; P-interaction=0.37) or actual thienopyridine use (P-interaction=0.24).. Vorapaxar reduced cardiovascular death, MI, or stroke in stable patients with a history of previous MI, whether treated concomitantly with a thienopyridine or not. The relative risk of moderate or severe bleeding was similarly increased irrespective of thienopyridine use.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Aged; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Internationality; Ischemic Attack, Transient; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Receptor, PAR-1; Receptors, Thrombin; Secondary Prevention; Stroke; Treatment Outcome

This study characterized a medically managed population in a non-ST-segment elevation acute coronary syndrome (NSTEACS) cohort and evaluated prognosis and outcomes of vorapaxar vs. placebo.. In the TRACER study, 12,944 NSTEACS patients were treated with standard care and vorapaxar (a novel platelet protease-activated receptor-1 antagonist) or placebo. Of those, 4194 patients (32.4%) did not undergo revascularization during index hospitalization, and 8750 (67.6%) underwent percutaneous coronary intervention or coronary artery bypass grafting. Patients managed medically were heterogeneous with different risk profiles, including 1137 (27.1%) who did not undergo coronary angiography. Patients who underwent angiography but were selected for medical management included those without evidence of significant coronary artery disease (CAD), with prior CAD but no new significant lesions, and with significant lesions who were not treated with revascularization.. Cardiovascular event rates were highest among those without angiography and lowest in the group with angiography but without CAD. In the medically managed cohort, 2-year primary outcome (cardiovascular death, myocardial infarction, stroke, recurrent ischaemia with rehospitalization, urgent coronary revascularization) event rates were 16.3% with vorapaxar and 17.0% with placebo (HR 0.99, 95% CI 0.83-1.17), with no interaction between drug and management strategy (p=0.75). Key secondary endpoint (cardiovascular death, myocardial infarction, stroke) rates were 13.4% with vorapaxar and 14.9% with placebo (HR 0.89, 95% CI 0.74-1.07), with no interaction (p=0.58). Vorapaxar increased GUSTO moderate/severe bleeding numerically in medically managed patients (adjusted HR 1.46, 95% CI 0.99-2.15).. NSTEACS patients who were initially medically managed had a higher risk-factor burden, and one-third had normal coronary arteries. Outcome in the medically managed cohort was significantly related to degree of CAD, highlighting the importance of coronary angiography. Efficacy and safety of vorapaxar appeared consistent with the overall trial results.

Topics: Acute Coronary Syndrome; Aged; Double-Blind Method; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Recurrence; Risk Factors; Stroke; Treatment Outcome

Clinical trials traditionally use time-to-first-event analysis embedded within the composite endpoint of cardiovascular death (CVD), myocardial infarction (MI), or stroke. However, many patients have >1 event, and this approach may not reflect overall experience. We addressed this by analyzing all cardiovascular events in TRACER.. TRACER randomized 12 944 patients with non-ST-segment elevation acute coronary syndromes to placebo or to protease-activated receptor 1 antagonist vorapaxar with a median follow-up of 502 days (interquartile range, 349 to 667). Analysis of vorapaxar's effect on recurrent CVD, MI, or stroke was prespecified using the Wei, Lin, and Weissfeld approach. Vorapaxar did not reduce the first occurrence of the primary endpoint of CVD, MI, stroke, revascularization, or rehospitalization for recurrent ischemia, but reduced the secondary composite endpoint of CVD, MI, or stroke (14.7% vorapaxar vs. 16.4% placebo; hazard ratio [HR], 0.89; 95% confidence interval [CI], 0.81 to 0.98; P=0.02; number needed to treat [NNT], 81). Recurrent secondary events occurred in 2.7% of patients. Vorapaxar reduced overall occurrences of ischemic events, first and subsequent (HR, 0.88; 95% CI, 0.80 to 0.98; P=0.02; NNT, 51). Also, there was a trend indicating that vorapaxar reduced the expanded endpoint, including revascularization and rehospitalization for recurrent ischemia (HR, 0.92; 95% CI, 0.84 to 1.01; P=0.09). Vorapaxar increased overall occurrences of moderate and severe Global Use of Strategies to Open Occluded Coronary Arteries bleeding (HR, 1.42; 95% CI, 1.21 to 1.66; P<0.001) and Thrombolysis in Myocardial Infarction clinically significant bleeding (HR, 1.550; 95% CI, 1.403 to 1.713; P<0.001).. Vorapaxar reduced overall occurrences of ischemic events, but increased bleeding. These exploratory findings broaden our understanding of vorapaxar's potential and expand our understanding of the value of capturing recurrent events.. ClinicalTrials.gov. Unique identifier: NCT00527943.

Topics: Acute Coronary Syndrome; Aged; Cardiovascular Diseases; Double-Blind Method; Female; Hemorrhage; Humans; Ischemia; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Proportional Hazards Models; Pyridines; Recurrence; Secondary Prevention; Stroke; Treatment Outcome

Protease-activated receptor 1 antagonism with vorapaxar represents a novel strategy for platelet inhibition. In TRACER, vorapaxar was compared with placebo plus standard of care among 12,944 patients with non-ST-segment elevation acute coronary syndromes. We anticipated that most patients would have received clopidogrel as part of standard care. We investigated the modification of vorapaxar's effect associated with clopidogrel use over time.. The marginal structural model method was used to estimate causal modification of vorapaxar effect by use of clopidogrel over time. The primary outcomes were the composite of cardiovascular death, myocardial infarction, or stroke and Global Use of Strategies to Open Occluded Coronary Arteries moderate or severe bleeding. The event accrual period excluded the time during which clopidogrel was clinically warranted.. Among 12,887 patients who received study medication, 11,117 (86.3%) received clopidogrel before randomization, of whom 38.5% stopped later in the trial (median time to stoppage 200 days with placebo; interquartile range [IQR] 14-367) (186 days with vorapaxar; IQR 17-366). In total, 1,770 (13.7%) patients were not on clopidogrel at randomization, of whom 47.8% started afterward (median time to start 2 days; IQR 2-4). During the period of event accrual, vorapaxar was associated with a 26% reduction in the composite of cardiovascular death, myocardial infarction, or stroke when used with clopidogrel (hazard ratio [HR] 0.74; 95% CI 0.60-0.91) and a 24% reduction when used without clopidogrel (HR 0.76; 95% CI 0.56-1.02) (interaction; P = .89). The hazard of Global Use of Strategies to Open Occluded Coronary Arteries bleeding with vorapaxar was not significantly different without clopidogrel (HR 1.33; 95% CI 0.81-2.20) or with clopidogrel (HR 1.09; 95% CI 0.76-1.56) (interaction; P = .53).. We observed no interaction between vorapaxar and clopidogrel after non-ST-segment elevation acute coronary syndromes on efficacy or safety outcomes, supporting a complementary role of protease-activated receptor 1 and P2Y12 antagonism.

Topics: Acute Coronary Syndrome; Aged; Clopidogrel; Drug Monitoring; Drug Therapy, Combination; Electrocardiography; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Secondary Prevention; Stroke; Survival Analysis; Ticlopidine; Treatment Outcome

Vorapaxar, a novel thrombin receptor antagonist, reduces cardiovascular death and recurrent thrombotic events when added to standard antiplatelet therapy in patients with stable atherosclerotic vascular disease.. The goal of this study was to test the hypothesis that treatment with vorapaxar reduces the rate of coronary stent thrombosis (ST) in stable patients with a history of coronary stenting.. TRA 2° P-TIMI 50 (Trial to Assess the Effects of Vorapaxar in Preventing Heart Attack and Stroke in Patients With Atherosclerosis-Thrombolysis In Myocardial Infarction 50) was a multinational, randomized, double-blind, placebo-controlled trial of vorapaxar in stable patients with prior myocardial infarction, peripheral arterial disease, or stroke. We evaluated the rates of definite ST as adjudicated by a central events committee using Academic Research Consortium (ARC) criteria.. A total of 26,449 patients were randomized, with 14,042 (53%) having a history of a coronary stent implantation before randomization, and an additional 449 patients receiving a coronary stent during the trial (total 14,491). During follow-up (median 2.5 years), there were 152 definite ST events, with the majority (92%) occurring late or very late. Vorapaxar reduced ARC definite ST (1.1% vs. 1.4%, hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.51 to 0.98; p = 0.037). The reduction was consistent, regardless of time from percutaneous coronary intervention, history of diabetes, use of drug-eluting stents, and use of dual antiplatelet therapy (DAPT) at randomization. Vorapaxar increased GUSTO moderate/severe bleeding (HR: 1.57, 95% CI: 1.26 to 1.94; p < 0.001).. The rate of ARC definite ST in stable patients, the majority of whom were receiving DAPT, was approximately 1.4% at 3 years. In stable patients with coronary stenting receiving standard antiplatelet therapy, vorapaxar administered for long-term secondary prevention significantly reduced ARC definite ST, including very late ST. (Trial to Assess the Effects of Vorapaxar [SCH 530348; MK-5348] in Preventing Heart Attack and Stroke in Patients With Atherosclerosis [TRA 2° P-TIMI 50] [P04737]; NCT00526474).

Topics: Aged; Atherosclerosis; Coronary Thrombosis; Double-Blind Method; Drug-Eluting Stents; Female; Follow-Up Studies; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Receptors, Thrombin; Stroke

Vorapaxar, a novel antiplatelet therapy, reduces thrombotic events in patients with a history of myocardial infarction (MI) or peripheral artery disease (PAD); however, because of an increased risk of intracranial hemorrhage, it is contraindicated in patients with a history of stroke.. The aim of this study was to investigate the incidence of new ischemic stroke and subsequent death or intracerebral hemorrhage in patients with MI or PAD and no cerebrovascular disease (CVD) treated with vorapaxar.. The TRA 2 °P-TIMI 50 (Trial to Assess the Effects of Vorapaxar in Preventing Heart Attack and Stroke in Patients With Atherosclerosis-Thrombolysis In Myocardial Infarction 50) was a randomized, double-blind, placebo-controlled trial of vorapaxar 2.5 mg daily in 26,449 patients with atherosclerosis, stratified by qualifying disease (MI, PAD, or CVD). A total of 20,170 patients with MI/PAD, but no CVD, were enrolled.. In patients with MI/PAD and no prior stroke or transient ischemic attack, vorapaxar reduced first ischemic stroke (hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.43 to 0.75; p < 0.001). The risk of hemorrhagic conversion after stroke (HR: 1.19, 95% CI: 0.49 to 2.91; p = 0.70) or death (HR: 1.09, 95% CI: 0.57 to 2.07; p = 0.79) during follow-up was not significantly increased with vorapaxar in patients who had a new ischemic stroke (n = 204). Although hemorrhagic stroke was increased (HR: 2.79, 95% CI: 1.00 to 7.73; p = 0.049), overall stroke was significantly reduced (HR: 0.67, 95% CI: 0.52 to 0.87; p = 0.002).. Vorapaxar reduces ischemic stroke in patients with MI or PAD and no known CVD. There does not appear to be a significant increase in the risk of hemorrhagic conversion or death in patients who experienced a first ischemic stroke on vorapaxar. Although primary hemorrhagic stroke is increased, vorapaxar reduces the total incidence of stroke. (Trial to Assess the Effects of Vorapaxar (SCH 530348; MK-5348) in Preventing Heart Attack and Stroke in Patients With Atherosclerosis [TRA 2 °P-TIMI 50]; NCT00526474).

Topics: Aged; Atherosclerosis; Brain Ischemia; Double-Blind Method; Female; Follow-Up Studies; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Receptors, Thrombin; Stroke; Treatment Outcome

Vorapaxar is a novel antagonist of protease-activated receptor-1, the primary receptor for thrombin on human platelets that is also present on vascular endothelium and smooth muscle. Patients with peripheral artery disease are at risk of systemic atherothrombotic events, as well as acute and chronic limb ischemia and the need for peripheral revascularization.. The Trial to Assess the Effects of SCH 530348 in Preventing Heart Attack and Stroke in Patients With Atherosclerosis (TRA2°P-TIMI 50) was a randomized, double-blind, placebo-controlled trial of vorapaxar in 26 449 patients with stable atherosclerotic vascular disease (myocardial infarction, stroke, or peripheral artery disease). Patients with qualifying peripheral artery disease (n=3787) had a history of claudication and an ankle-brachial index of <0.85 or prior revascularization for limb ischemia. The primary efficacy end point was cardiovascular death, myocardial infarction, or stroke, and the principal safety end point was Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) bleeding. In the peripheral artery disease cohort, the primary end point did not differ significantly with vorapaxar (11.3% versus 11.9%; hazard ratio, 0.94; 95% confidence interval, 0.78-1.14; P=0.53). However, rates of hospitalization for acute limb ischemia (2.3% versus 3.9%; hazard ratio, 0.58; 95% confidence interval, 0.39-0.86; P=0.006) and peripheral artery revascularization (18.4% versus 22.2%; hazard ratio, 0.84; 95% confidence interval, 0.73-0.97; P=0.017) were significantly lower in patients randomized to vorapaxar. Bleeding occurred more frequently with vorapaxar compared with placebo (7.4% versus 4.5%; hazard ratio, 1.62; 95% confidence interval, 1.21-2.18; P=0.001).. Vorapaxar did not reduce the risk of cardiovascular death, myocardial infarction, or stroke in patients with peripheral artery disease; however, vorapaxar significantly reduced acute limb ischemia and peripheral revascularization. The beneficial effects of protease-activated receptor-1 antagonism on limb vascular events were accompanied by an increased risk of bleeding.

Topics: Aged; Ankle Brachial Index; Cohort Studies; Comorbidity; Double-Blind Method; Extremities; Female; Follow-Up Studies; Hemorrhage; Humans; Ischemia; Kaplan-Meier Estimate; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Pyridines; Receptor, PAR-1; Risk Factors; Stroke; Thrombin; Treatment Outcome

The TRA·CER trial compared vorapaxar, a novel platelet protease-activated receptor (PAR)-1 antagonist, with placebo in 12 944 patients with high-risk non-ST-segment elevation acute coronary syndromes (NSTE ACS). In this analysis, we explored the effect of vorapaxar on myocardial infarction (MI).. A blinded, independent central endpoint adjudication committee prospectively defined and classified MI according to the universal MI definition, including peak cardiac marker value (creatine kinase-MB [CK-MB] and/or troponin). Because the trial failed to meet its primary endpoint, these analyses are considered exploratory. During a median follow-up of 502 days, 1580 MIs occurred in 1319 patients. The majority (n = 1025, 64.9%) were type 1 (spontaneous) MI, followed by type 4a [percutaneous coronary intervention (PCI)-related] MI (n = 352; 22.3%). Compared with placebo, vorapaxar reduced the hazard of a first MI of any type by 12% [hazard ratio (HR), 0.88; 95% confidence interval (CI), 0.79-0.98; P = 0.021] and the hazard of total number of MIs (first and subsequent) by 14% (HR, 0.86; 95% CI, 0.77-0.97; P = 0.014), an effect that was sustained over time. Vorapaxar reduced type 1 MI by 17% (HR, 0.83; 95% CI, 0.73-0.95; P = 0.007). Type 4a MIs were not significantly reduced by vorapaxar (HR, 0.90; 95% CI, 0.73-1.12; P = 0.35). Vorapaxar effect was consistent across MI sizes defined by peak cardiac marker elevations and across key clinical subgroups; however, in patients not treated with thienopyridine at baseline (HR, 0.65; 95% CI, 0.46-0.92) compared with patients who received thienopyridine (HR, 0.91; 95% CI, 0.81-1.02), there was a trend towards a higher effect (Pint = 0.077).. The PAR-1 antagonist vorapaxar was associated with a reduction of MI, including total number of infarctions. This reduction was sustained over time and was mostly evident in type 1 MI, the most common type of MI observed.

Topics: Acute Coronary Syndrome; Biomarkers; Creatine Kinase, MB Form; Double-Blind Method; Follow-Up Studies; Humans; Lactones; Myocardial Infarction; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Prospective Studies; Pyridines; Receptor, PAR-1; Troponin

Vorapaxar is an antiplatelet agent that antagonizes thrombin-mediated activation of the protease-activated receptor-1 on platelets. We tested the efficacy and safety of vorapaxar in a prespecified analysis in the stroke subcohort from a multinational, randomized, placebo-controlled trial.. We randomly assigned patients with prior atherothrombosis (myocardial infarction, peripheral artery disease, or ischemic stroke) to receive vorapaxar (2.5 mg daily) or placebo added to standard antiplatelet therapy. Patients who qualified with stroke (N=4883) had a history of ischemic stroke in the prior 2 weeks to 12 months. The primary end point was the composite of cardiovascular death, myocardial infarction, or any stroke.. The qualifying stroke was classified as large vessel in 35%, small vessel in 47%, and other/unknown in 18%. In the stroke cohort, cardiovascular death, myocardial infarction, or stroke through 3 years was not reduced with vorapaxar versus placebo (13.0% vs 11.7%; hazard ratio, 1.03; 95% confidence interval, 0.85-1.25), including recurrent ischemic stroke (hazard ratio, 0.99; 95% confidence interval, 0.78-1.25). There were no significant differences in the effect of vorapaxar based on the type or timing of the qualifying stroke. Intracranial hemorrhage at 3 years was increased with vorapaxar (2.5% vs 1.0%; hazard ratio, 2.52; 95% confidence interval, 1.46-4.36).. In patients with prior ischemic stroke who receive standard antiplatelet therapy, adding vorapaxar increased the risk of intracranial hemorrhage without an improvement in major vascular events, including ischemic stroke. These findings add to the accumulating evidence establishing important risks with combination antiplatelet therapy in patients with prior stroke. Clinical Trial Registration Information- http://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Aged; Double-Blind Method; Female; Humans; International Cooperation; Intracranial Hemorrhages; Kaplan-Meier Estimate; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Risk Factors; Stroke; Treatment Outcome

Thrombin potently activates platelets through the protease-activated receptor PAR-1. Vorapaxar is a novel antiplatelet agent that selectively inhibits the cellular actions of thrombin through antagonism of PAR-1.. We randomly assigned 26,449 patients who had a history of myocardial infarction, ischemic stroke, or peripheral arterial disease to receive vorapaxar (2.5 mg daily) or matching placebo and followed them for a median of 30 months. The primary efficacy end point was the composite of death from cardiovascular causes, myocardial infarction, or stroke. After 2 years, the data and safety monitoring board recommended discontinuation of the study treatment in patients with a history of stroke owing to the risk of intracranial hemorrhage.. At 3 years, the primary end point had occurred in 1028 patients (9.3%) in the vorapaxar group and in 1176 patients (10.5%) in the placebo group (hazard ratio for the vorapaxar group, 0.87; 95% confidence interval [CI], 0.80 to 0.94; P<0.001). Cardiovascular death, myocardial infarction, stroke, or recurrent ischemia leading to revascularization occurred in 1259 patients (11.2%) in the vorapaxar group and 1417 patients (12.4%) in the placebo group (hazard ratio, 0.88; 95% CI, 0.82 to 0.95; P=0.001). Moderate or severe bleeding occurred in 4.2% of patients who received vorapaxar and 2.5% of those who received placebo (hazard ratio, 1.66; 95% CI, 1.43 to 1.93; P<0.001). There was an increase in the rate of intracranial hemorrhage in the vorapaxar group (1.0%, vs. 0.5% in the placebo group; P<0.001).. Inhibition of PAR-1 with vorapaxar reduced the risk of cardiovascular death or ischemic events in patients with stable atherosclerosis who were receiving standard therapy. However, it increased the risk of moderate or severe bleeding, including intracranial hemorrhage. (Funded by Merck; TRA 2P-TIMI 50 ClinicalTrials.gov number, NCT00526474.).

Topics: Aged; Brain Ischemia; Cardiovascular Diseases; Double-Blind Method; Female; Hemorrhage; Humans; Intracranial Hemorrhages; Kaplan-Meier Estimate; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Receptor, PAR-1; Retreatment; Risk; Secondary Prevention; Stroke

Vorapaxar inhibits platelet activation by antagonising thrombin-mediated activation of the protease-activated receptor 1 on human platelets. The effect of adding other antiplatelet drugs to aspirin for long-term secondary prevention of thrombotic events in stable patients with previous myocardial infarction is uncertain. We tested this effect in a subgroup of patients from the Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events (TRA 2°P)-TIMI 50 trial.. In TRA 2°P-TIMI 50--a randomised, placebo-controlled, parallel trial--we randomly assigned patients with a history of atherothrombosis to receive vorapaxar (2·5 mg daily) or matching placebo in a 1:1 ratio. Patients, and those giving treatment, assessing outcomes, and analysing results were masked to treatment allocation. Patients with a qualifying myocardial infarction within the previous 2 weeks to 12 months were analysed as a pre-defined subgroup. The primary efficacy endpoint was cardiovascular death, myocardial infarction, or stroke, analysed by intention to treat. We analysed events by Kaplan-Meier analysis and compared groups with a Cox proportional hazard model. TRA 2°P-TIMI 50 is registered at ClinicalTrials.gov (NCT00526474).. 17,779 of 26,449 patients had a qualifying myocardial infarction and were assigned treatment (8898 to vorapaxar and 8881 to placebo). Median follow-up was 2·5 years (IQR 2·0-2·9). Cardiovascular death, myocardial infarction, or stroke occurred in 610 of 8898 patients in the vorapaxar group and 750 of 8881 in the placebo group (3-year Kaplan-Meier estimates 8·1%vs 9·7%, HR 0·80, 95% CI 0·72-0·89; p<0·0001). Moderate or severe bleeding was more common in the vorapaxar group versus the placebo group (241/8880 [3·4%, 3-year Kaplan-Meier estimate] vs 151/8849 [2·1%, 3-year Kaplan-Meier estimate], HR 1·61, 95% CI 1·31-1·97; p<0·0001). Intracranial haemorrhage occurred in 43 of 8880 patients (0·6%, 3-year Kaplan-Meier estimate) with vorapaxar versus 28 of 8849 (0·4%, 3-year Kaplan-Meier estimate) with placebo (p=0·076). Other serious adverse events were equally distributed between groups.. For patients with a history of myocardial infarction, inhibition of protease-activated receptor 1 with vorapaxar reduces the risk of cardiovascular death or ischaemic events when added to standard antiplatelet treatment, including aspirin, and increases the risk of moderate or severe bleeding.. Merck.

Topics: Aged; Cardiovascular Diseases; Double-Blind Method; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Pyridines; Receptor, PAR-1; Secondary Prevention; Stroke; Thrombosis

An antithrombotic drug is needed that safely reduces cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). We therefore assessed the tolerability and safety of SCH 530348-an oral platelet protease-activated receptor-1 antagonist.. We randomly assigned patients aged 45 years or older and undergoing non-urgent PCI or coronary angiography with planned PCI to an oral loading dose of SCH 530348 (10 mg, 20 mg, or 40 mg) or matching placebo in a 3:1 ratio in a multicentre international study. Those in the SCH 530348 group who subsequently underwent PCI (primary PCI cohort) continued taking an oral maintenance dose (0.5 mg, 1.0 mg, or 2.5 mg per day), and patients in the placebo group continued placebo for 60 days. The primary endpoint was the incidence of clinically significant major or minor bleeding according to the thrombolysis in myocardial infarction (TIMI) scale. Both investigators and patients were unaware of treatment allocation. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00132912.. 257 patients were assigned to placebo and 773 to SCH 530348. The primary endpoint occurred in 2 (2%) of 129, 3 (3%) of 120, and 7 (4%) of 173 patients, respectively, in the SCH 530348 10 mg, 20 mg, and 40 mg groups compared with 5 (3%) of 151 patients in the placebo group (p=0.5786). TIMI major plus minor bleeding occurred in 3 (2%) of 136, 5 (4%) of 139, and 4 (3%) of 138 patients given SCH 530348 0.5 mg, 1.0 mg, and 2.5 mg once per day, respectively (p=0.7561).. Oral SCH 530348 was generally well tolerated and did not cause increased TIMI bleeding, even when administered concomitantly with aspirin and clopidogrel. Further testing in phase III trials to accurately define the safety and efficacy of SCH 530348 is warranted.

Topics: Angioplasty, Balloon, Coronary; Coronary Disease; Double-Blind Method; Drug-Related Side Effects and Adverse Reactions; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Receptors, Thrombin

Quantitative benefit-risk (B-R) assessments are used to characterize treatment by combining key benefits and risks into a single metric but have historically been done for the "average" patient. Our aim was to conduct an individualized assessment for the oral antiplatelet vorapaxar by combining trial and real-world data to further personalize the treatment profiles.. Using linked UK health care databases, we developed risk prediction equations for key ischemic and bleeding events using Cox proportional hazards models. Trial hazard ratios, relative to placebo, were applied to baseline risk estimates to compute expected attributable risks, summed to derive a per-patient net clinical benefit (NCB). High risk subgroups were defined a priori, and Gaussian mixture models (GMM) were fit to characterize the NCB distribution and identify subgroups with similar NCBs.. NCB was consistently positive for all subgroups, likely due to the outcome correlation, and would remain positive with a 12-fold increase in bleeding risk. GMMs identified three distinct NCB subgroups. Compared with the middle/lower NCB subgroups, those with a higher NCB tended to be older, female, and have higher CV disease burden.. Personalized B-R assessments are feasible and clinically valuable and can be used to better predict who would benefit most from therapy.

Topics: Age Factors; Aged; Aged, 80 and over; Clinical Decision-Making; Comorbidity; Databases, Factual; Feasibility Studies; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Normal Distribution; Patient Selection; Placebos; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Secondary Prevention; Sex Factors; Treatment Outcome; United Kingdom

Topics: Age Factors; Aged; Aged, 80 and over; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Secondary Prevention; Stroke; Thrombosis; Time Factors; Treatment Outcome

To evaluate long-term health benefits and risks of adding vorapaxar (VOR) to the standard care antiplatelet therapy (SC) of aspirin and/or clopidogrel, among a population with a recent myocardial infarction (MI) and/or peripheral artery disease (PAD).. In a state-transition model, patients transition between health states (event-free, recurrent MI, stroke, death), while at risk of experiencing non-transition-related revascularization and non-fatal bleeding events. Risk equations developed from the TRA 2°P-TIMI 50 trial's patient-level data were used to predict cardiovascular (CV) outcomes over longer time horizons. Additional sources, including trials and US-based observational studies, informed the inputs for short-term CV risk, non-CV death, and health-related quality of life. Survival and quality-adjusted life-years (QALYs) were estimated over a lifetime horizon, discounted at 3% per year.. Within a cohort of 7361 patients with recent MI and/or PAD, VOR + SC relative to SC alone yielded 176 fewer CV events (MIs, strokes, or CV deaths), but 27 more major bleeding events. VOR + SC was associated with increased life expectancy and health benefits (19.93 undiscounted life-years [LYs], 9.57 discounted QALYs vs. 19.61 undiscounted LYs, 9.41 discounted QALYs). The results were most sensitive to scenarios varying time of vorapaxar initiation, and the assumptions in the 90 day period post-MI. Additional analyses showed that add-on vorapaxar provides consistent incremental benefits in high-risk subgroups.. This study contributes to the growing literature on secondary prevention add-on therapy, as results from these modeling analyses suggest that adding vorapaxar to SC for patients at high atherothrombotic risk can provide long-term health benefits.

Topics: Aspirin; Clopidogrel; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Quality of Life; Quality-Adjusted Life Years; Secondary Prevention; Stroke; Thrombosis; Ticlopidine

We aim to evaluate the potential benefit and risk of addition of vorapaxar to standard medical therapy in patients who underwent coronary revascularization with either percutaneous coronary revascularization or coronary artery bypass graft surgery. We searched PubMed, EMBASE, the Cochrane Central Register of Controlled trials, and the clinical trial registry maintained at clinicaltrials.gov for randomized control trials evaluating the safety and efficacy of vorapaxar in patients who underwent coronary revascularization procedures with either percutaneous coronary revascularization or coronary artery bypass graft surgery. Event rates were compared using a Forest plot of relative risk using a random-effects model. The 5 studies (n = 24,025) that met all criteria were included in the final analysis. After coronary revascularization procedures, addition of vorapaxar to standard medical therapy was associated with reduction in the risk of myocardial infarction (MI; risk ratio 0.83 [0.75 to 0.92]) and ischemic stroke (0.011 [0.007 to 0.016]); however, it also resulted in significant increase risk of hemorrhagic stroke (1.57 [1.01 to 2.44]) and Thrombolysis In Myocardial Infarction major and minor bleeds (1.36 [1.07 to 1.70]). There was no significant difference in the risk of cardiovascular mortality (0.90 [0.73 to 1.09]), repeat revascularization (0.78 [0.23 to 2.70]), and stent thrombosis (0.95 [0.62 to 1.45]) in the vorapaxar and control groups. In conclusion, after coronary revascularization procedures, addition of vorapaxar to standard medical therapy was associated with reduction in the risk of MI and ischemic stroke and increase in risk of hemorrhagic stroke and Thrombolysis In Myocardial Infarction major and minor bleeds.

Topics: Combined Modality Therapy; Coronary Artery Bypass; Humans; Lactones; Myocardial Infarction; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Pyridines; Risk Assessment

Despite advanced techniques and improved clinical outcomes, the optimal antiplatelet strategy following coronary artery bypass grafting (CABG) is an unsolved mystery. Vorapaxar, a novel platelet thrombin receptor (PAR-1/4) blocker, is currently approved for post-myocardial infarction and peripheral artery disease indications on top of clopidogrel or/and aspirin. We here summarize the outcomes in patients after CABG for justification of a future vorapaxar trial. We comprehended the CABG outcomes after vorapaxar yielded from TRACER, TRA2P trials, and affiliated FDA reviews. The verified evidence suggests that composite of death, myocardial infarction and stroke occurred in 2.2% of vorapaxar vs. 8.1% placebo in TRA2P. These data were similar to the endpoint differences (5.9% after vorapaxar vs. 8.3% for placebo) in TRACER. The mortality reduction also consistently suggests vorapaxar advantage (1.7% vs. 2.5% in TRA2P, and 1.7% vs. 3.9% in TRACER). Notably, the post-CABG bleeding risks after vorapaxar were only slightly, but not significantly higher. Moreover, the bleeding disadvantage in the experimental arm was most likely related to overtreatment since majority of patients in both TRACER and TRA2P received triple antiplatelet therapy with aspirin, clopidogrel on top of vorapaxar. Overall, the FDA-confirmed evidence advocate for the future vorapaxar post-CABG outcome-driven trial. The head-to-head trial testing dual therapy with continued over CABG vorapaxar versus withdrawed clopidogrel, both on top of low dose aspirin is warranted. We conclude that the primary outcomes including mortality were consistently better for heart surgery patients after vorapaxar, while the excess of bleeding was mild. Continuing vorapaxar during CABG may be superior to currently recommended withdrawal antiplatelet strategies, and should be tested in an adequately powered randomized outcome-driven trial.

Topics: Aspirin; Clopidogrel; Coronary Artery Bypass; Coronary Artery Disease; Female; Humans; Lactones; Male; Myocardial Infarction; Postoperative Hemorrhage; Pyridines; Survival Analysis; Ticlopidine; Treatment Outcome

The TRA 2°P-TIMI 50 trial showed the addition of vorapaxar to standard care (SC) antiplatelet therapy reduced the combined risk of death, myocardial infarction (MI), and stroke, while exhibiting an increase in moderate, but not other bleeding events.. Our objective was to estimate the long-term health benefits and risks of vorapaxar as an add-on to SC treatment (lifetime aspirin and up to 12 months of clopidogrel) for patients with a prior MI and without a history of cerebrovascular disease.. In the state transition model we developed, the patients transition between states due to recurrent MI, stroke, or death, and are at risk of non-fatal bleeding. Risk equations were developed from individual patient-level data from the TRA 2°P-TIMI 50 trial to predict long-term cardiovascular (CV) outcomes. Additional sources informed inputs for case fatality, bleeding rates on SC, risk of non-CV death, and utilities.. Over a lifetime horizon, fewer CV events and more bleeding events occurred in the vorapaxar (VOR) + SC arm, relative to the SC-only arm. These results were ultimately accompanied by an increase in life expectancy and health benefits associated with add-on vorapaxar treatment, as the VOR + SC arm yielded an average of 8.27 discounted quality-adjusted life-years (QALYs) compared with an average of 7.96 discounted QALYs in the SC-only arm.. This model framework leveraged novel risk equations to make long-term projections of CV events in a population at high risk of recurrence. Model results suggest vorapaxar is most effective as add-on therapy to SC antiplatelet treatment when initiated upon hospital discharge post-MI.

Topics: Aspirin; Cardiovascular System; Clopidogrel; Hemorrhage; Humans; Lactones; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Secondary Prevention; Stroke; Thrombosis; Ticlopidine; Treatment Outcome

Our dual aims were as follows: (1) to classify new or recurrent myocardial infarctions (MI) in patients with stable atherosclerosis using the Universal Definition of MI classification system; and (2) to characterize the effects of vorapaxar, a first-in-class platelet protease-activated receptor -1 antagonist, on new or recurrent MI.. We analyzed data from TRA 2°P-TIMI 50, a multinational, randomized, double-blind, placebo-controlled trial of vorapaxar. This analysis included 20 770 patients with previous MI or peripheral arterial disease without a history of transient ischemic attack or stroke. Each new or recurrent MI after randomization that met the trial end point definition was further categorized according to the European Society of Cardiology, American College of Cardiology, American Heart Association, World Heart Federation Universal Definition classification of type and size. Of 1095 incident MIs, 77% were spontaneous (Type 1), with a smaller number (9.8%) of secondary MIs (Type 2). Vorapaxar reduced Type 1 MI (hazard ratio [HR] 0.84, CI 0.73-0.98, P=0.024), with a similar pattern for Type 2 MI (HR 0.74, CI 0.49-1.10, P=0.13). Notably, vorapaxar showed a consistent pattern of reduction across size of MIs, including MIs in the highest Universal MI size class (≥10× upper reference limit, HR 0.83, CI 0.70-0.98, P=0.025). As such, there was a significant reduction in larger, spontaneous MIs (Type 1, ≥10× upper reference limit, HR 0.81, CI 0.67-0.99, P=0.036), and a consistent pattern with respect to fatal MI (HR 0.66, CI 0.39-1.11, P=0.12).. Among stable patients with established atherosclerosis, the most common type of incident MI is spontaneous MI, and the reduction in MI with vorapaxar was consistent across MIs of varying type and size, including spontaneous infarctions ≥10× upper reference limit.. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Topics: Aged; Atherosclerosis; Coronary Artery Disease; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Proportional Hazards Models; Pyridines; Randomized Controlled Trials as Topic; Recurrence; Secondary Prevention

Antithrombotic therapy plays an important role in the treatment of non-ST-segment elevation acute coronary syndromes (NSTE ACS) but is associated with bleeding risk. Advanced age may modify the relationship between efficacy and safety.. Efficacy and safety of vorapaxar (a protease-activated receptor 1 antagonist) was analyzed across ages as a continuous and a categorical variable in the 12,944 patients with NSTE ACS enrolled in the TRACER trial. To evaluate the effect of age, Cox regression models were developed to estimate hazard ratios (HRs) with the adjustment of other baseline characteristics and randomized treatment for the primary efficacy composite of cardiovascular death, myocardial infarction (MI), stroke, recurrent ischemia with rehospitalization, or urgent coronary revascularization, and the primary safety composite of moderate or severe Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) bleeding.. The median age of the population was 64years (25th, 75th percentiles = 58, 71). Also, 1,791 patients (13.8%) were ≤54years of age, 4,968 (38.4%) were between 55 and 64 years, 3,979 (30.7%) were between 65 and 74 years, and 2,206 (17.1%) were 75years or older. Older patients had higher rates of hypertension, renal insufficiency, and previous stroke and worse Killip class. The oldest age group (≥75years) had substantially higher 2-year rates of the composite ischemic end point and moderate or severe GUSTO bleeding compared with the youngest age group (≤54years). The relationships between treatment assignment (vorapaxar vs placebo) and efficacy outcomes did not vary by age. For the primary efficacy end point, the HRs (95% CIs) comparing vorapaxar and placebo in the 4 age groups were as follows: 1.12 (0.88-1.43), 0.88 (0.76-1.02), 0.89 (0.76-1.04), and 0.88 (0.74-1.06), respectively (P value for interaction = .435). Similar to what was observed for efficacy outcomes, we did not observe any interaction between vorapaxar and age on bleeding outcomes. For the composite of moderate or severe bleeding according to the GUSTO classification, the HRs (95% CIs) comparing vorapaxar and placebo in the 4 age groups were 1.73 (0.89-3.34), 1.39 (1.04-1.86), 1.10 (0.85-1.42), and 1.73 (1.29-2.33), respectively (P value for interaction = .574).. Older patients had a greater risk for ischemic and bleeding events; however, the efficacy and safety of vorapaxar in NSTE ACS were not significantly influenced by age.

Topics: Acute Coronary Syndrome; Age Factors; Aged; Cardiovascular Diseases; Double-Blind Method; Female; Hemorrhage; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Patient Readmission; Platelet Aggregation Inhibitors; Proportional Hazards Models; Pyridines; Randomized Controlled Trials as Topic; Recurrence; Stroke; Treatment Outcome

Topics: Diabetes Mellitus; Female; Humans; Lactones; Male; Myocardial Infarction; Pyridines; Receptors, Thrombin; Secondary Prevention; Stroke; Thrombosis

Topics: Hemorrhage; Humans; Lactones; Myocardial Infarction; Patient Selection; Peripheral Arterial Disease; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Receptor, PAR-1; Thrombosis

There are consistent data suggesting that elderly patients benefit from less aggressive antiplatelet strategies following acute coronary syndromes. This observation is likely because advanced age is associated with greater bleeding and potentially less efficacy. Oral antiplatelet agents are often prescibed uniformly, without dose adjustments, representing a concerning reality for this patient population. Vorapaxar, a platelet thrombin PAR-1 inhibitor, has been evaluated in the TRA2P and TRACER trials, but drug efficacy and safety, with respect to age, were not discussed in detail. We sought to define the FDA-confirmed age-dependent clinical outcomes after vorapaxar. The mean and median ages in the TRA2P indicated population were about 60 years, with 33.4% greater than 65 years of age and 9.2% greater than 75 years of age. Vorapaxar efficacy was reduced in those aged 72 or older, while bleeding rates gradually increased with age for both arms. For patients aged 75 or older, efficacy numerically favored vorapaxar, but this interaction was not statistically significant (HR=1.18; 95% CI=0.95-1.46; p=0.132). In TRACER, the point estimates by age quintile for the primary endpoint also favored vorapaxar, except for the lowest age quintile ≤56 probably due to overtreatment. GUSTO moderate/severe bleeding was substantially higher with vorapaxar in both trials for the eldest age quintile (5.1% placebo vs. 7.0% vorapaxar in TRA2P; 8.4% placebo vs. 13% vorapaxar in TRACER). In conclusion, the FDA analyses reassure that vorapaxar efficacy is not reduced in the elderly. However, the bleeding risk after vorapaxar is definitely increased with advancing age.

Topics: Acute Coronary Syndrome; Aged; Female; Humans; Lactones; Male; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines; Randomized Controlled Trials as Topic; Receptor, PAR-1; United States; United States Food and Drug Administration

Topics: Drug Approval; Drug Interactions; Drug Therapy, Combination; Humans; Lactones; Myocardial Infarction; Peripheral Arterial Disease; Pyridines; Receptor, PAR-1; Thrombosis; United States; United States Food and Drug Administration

Topics: Acute Coronary Syndrome; Humans; Lactones; Myocardial Infarction; Platelet Aggregation Inhibitors; Pyridines

Protease-activated receptor 1 (PAR1) is the prototypical member of a family of G-protein-coupled receptors that mediate cellular responses to thrombin and related proteases. Thrombin irreversibly activates PAR1 by cleaving the amino-terminal exodomain of the receptor, which exposes a tethered peptide ligand that binds the heptahelical bundle of the receptor to affect G-protein activation. Here we report the 2.2 Å resolution crystal structure of human PAR1 bound to vorapaxar, a PAR1 antagonist. The structure reveals an unusual mode of drug binding that explains how a small molecule binds virtually irreversibly to inhibit receptor activation by the tethered ligand of PAR1. In contrast to deep, solvent-exposed binding pockets observed in other peptide-activated G-protein-coupled receptors, the vorapaxar-binding pocket is superficial but has little surface exposed to the aqueous solvent. Protease-activated receptors are important targets for drug development. The structure reported here will aid the development of improved PAR1 antagonists and the discovery of antagonists to other members of this receptor family.

Topics: Amino Acid Motifs; Binding Sites; Crystallization; Crystallography, X-Ray; Enzyme Activation; Humans; Hydrolysis; Lactones; Ligands; Models, Molecular; Molecular Dynamics Simulation; Myocardial Infarction; Protein Conformation; Pyridines; Receptor, PAR-1; Receptors, G-Protein-Coupled; Receptors, Thrombin