Mortality at 1 year for the direct comparison of tirofiban and abciximab during percutaneous coronary revascularization: do tirofiban and ReoPro give similar efficacy outcomes at trial 1-year follow-up

Efficacy and safety of intracoronary versus intravenous tirofiban in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: A meta-analysis of randomized controlled trials

Background

Effective antiplatelet therapy is critical for patients with ST-segment elevation myocardial infarction (STEMI) and receiving primary percutaneous coronary interventions (PPCI). Intracoronary (IC) and intravenous (IV) administration of tirofiban are commonly used during the procedure of PPCI. However, which is the better administration route of tirofiban have not been fully evaluated.

Methods

A comprehensive literature search of RCTs that comparing IC with IV tirofiban in STEMI patients undergoing PPCI was conducted, which were published as of May 7, 2022, in PubMed, Embase, Cochrane Library, Web of Science, Scopus and ClinicalTrials.gov. The primary efficacy endpoint was 30-day major adverse cardiovascular events (MACE) and the primary safety endpoint was in-hospital bleeding events.

Results

This meta-analysis included 9 trials involving 1177 patients. IC tirofiban significantly reduced the incidence of 30-day MACE (RR 0.65, 95% CI: 0.44 to 0.95, P = 0.028) and improved the rate of the thrombolysis in myocardial infarction (TIMI) grade 3 flow in high-dose (25 μg/kg) group (RR = 1.13, 95% CI: 0.99-1.30, P = 0.001), in-hospital (WMD 2.03, 95% CI: 1.03 to 3.02, P < 0.001), and 6-month left ventricular injection fraction (LVEF) (WMD 6.01, 95% CI: 5.02 to 6.99, P < 0.001) compared with IV. There was no significant difference in the incidences of in-hospital bleeding events (RR 0.96, 95% CI: 0.67 to 1.38, P = 0.82) and thrombocytopenia (RR 0.63, 95% CI: 0.26 to 1.57, P = 0.32) between the two groups.

Conclusions

IC tirofiban significantly improved the incidence of TIMI 3 in the high-dose group, in-hospital and 6-month LVEF, and reduced the 30-day MACE incidence without increasing the risk of bleeding compared with IV.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Progress in the development of antiplatelet agents: Focus on the targeted molecular pathway from bench to clinic

Antiplatelet drugs serve as a first-line antithrombotic therapy for the management of acute ischemic events and the prevention of secondary complications in vascular diseases. Numerous antiplatelet therapies have been developed; however, currently available agents are still associated with inadequate efficacy, risk of bleeding, and variability in individual response. Understanding the mechanisms of platelet involvement in thrombosis and the clinical development process of antiplatelet agents is critical for the discovery of novel agents. The functions of platelets in thrombosis are regulated by two major mechanisms: the interaction between surface receptors and their ligands, and the downstream intracellular signaling pathways. Recently, most of the progress made in antiplatelet drug development has been achieved with P2Y receptor antagonists. Additionally, the usage of GP IIb/IIIa receptor antagonists has decreased, because it is associated with a higher risk of bleeding and thrombocytopenia. Agents targeting other platelet surface receptors such as PARs, TP receptor, EP3 receptor, GPIb-IX-V receptor, P-selectin, as well as intracellular signaling factors, such as PI3Kβ, have been evaluated in an attempt to develop the next generation of antiplatelet drugs, reduce or eliminate interpatient variability of drug efficacy and significantly lower the risk of drug-induced bleeding. The aim of this review is to describe the pathways of platelet activation in thrombosis, and summarize the development process of antiplatelet agents, as well as the preclinical and clinical evaluations performed on these agents.

Definitions of peri-procedural myocardial infarction and the association with one-year mortality: Insights from CHAMPION trials

BACKGROUND

Controversies exist over the appropriate definition for peri-procedural myocardial infarction (PPMI) and its association with mortality. This study aims to evaluate one-year survival following percutaneous coronary intervention (PCI) and the association of different definitions of PPMI with survival among patients with stable angina (SA) or acute coronary syndrome (ACS) in the contemporary era.

METHODS

We used data from the CHAMPION PLATFORM and CHAMPION PCI trials of patients undergoing PCI and conducted univariable and multivariable Cox proportional hazard regression models to evaluate mortality risk during the first year after PCI. A blinded events committee adjudicated suspected PPMI defined by biomarker elevations ≥3× the upper limit of normal (ULN) or new Q-waves. We further analyzed PPMI by the magnitude of CK-MB elevation ([a] 3 to <5× ULN, [b] 5 to <10× ULN, [c] ≥10× ULN) or by the 2^nd universal definition of myocardial infarction (UDMI_CK-MB) excluding patients with evidence of myocardial infarction (MI) prior to PCI.

RESULTS

Of 13,968 patients, 11% initially presented with SA, and 89% with ACS. One-year mortality was 3.4% (SA: 1.5%; ACS: 3.6%). PPMI occurred in 6.3% of the patients (3 to <5× ULN: 2.5%; 5 to <10× ULN: 2.1%; ≥10× ULN: 1.6%; UDMI_CK-MB: 2.7%). After multivariable adjustment, a significantly higher risk of one-year mortality was observed for patients with PPMI compared with patients without PPMI (HR 2.35 [1.74-3.18], p < 0.001; 3 to <5× ULN: 1.55 [0.92-2.62], p = 0.10; 5 to <10× ULN: 1.22 [0.67-2.20], p = 0.52; ≥10× ULN: 4.78 [3.06-7.47], p < 0.001; UDMI_CK-MB: 2.19 [1.29-3.73], p = 0.004).

CONCLUSION

PPMI occurred in 6.3% of the patients and was associated with increased risk of death within one year. Survival was not significantly impacted by PPMI if defined by periprocedural CK-MB elevations <10× ULN alone and without additional evaluation of symptoms or evidence of ischemia. These findings highlight the importance of PPMI for long-term outcome in the contemporary era and of its definition in the planning and interpretation of clinical trials.

Efficacy and safety of abciximab in diabetic patients who underwent percutaneous coronary intervention with thienopyridines loading: a meta-analysis

BACKGROUND

It has been controversial whether abciximab offered additional benefits for diabetic patients who underwent percutaneous coronary intervention (PCI) with thienopyridines loading.

METHODS

MEDLINE, EMBASE, the Cochrane library clinical trials registry, ISI Science Citation Index, ISI Web of Knowledge and China National Knowledge Infrastructure (CNKI) were searched, supplemented with manual-screening for relevant publications. Quantitative meta-analyses were performed to assess differences between abciximab groups and controls with respect to post-PCI risk of major cardiac events (MACEs), angiographic restenosis and bleeding complications.

RESULTS

9 trials were identified, involving 2,607 diabetic patients receiving PCI for coronary artery diseases. Among those patients who underwent elective PCI or primary PCI, pooling results showed that abciximab did not significantly reduce risks of MACEs (for elective-PCI patients: RR(1-month): 0.93, 95% CI: 0.60-1.44; RR(1-year): 0.95, 95% CI: 0.81-1.11; for primary-PCI patients: RR(1-month): 1.05, 95% CI: 0.70-1.57; RR(1-year): 0.98, 95% CI: 0.80-1.21), nor all-cause mortality, re-infarction and angiographic restenosis in either group. The only beneficial effect by abciximab appeared to be a decrease 1-year TLR (target lesion revascularization) risk in elective-PCI patients (RR1-year: 0.83, 95% CI: 0.70-0.99). Moreover, occurrence of minor bleeding complications increased in elective-PCI patients treated with abciximab (RR: 2.94, 95% CI: 1.68-5.13, P<0.001), whereas major bleedings rate was similar (RR: 0.83, 95% CI: 0.27-2.57).

CONCLUSIONS

Concomitant dosing of abciximab and thienopyridines provides no additional benefit among diabetic patients who underwent PCI; this conclusion, though, needs further confirmation in larger studies.

Clinical pharmacology of antithrombotic drugs in coronary artery disease

Coronary heart disease is the leading cause of death in the Western world. Antithrombotic therapy is the cornerstone of its successful treatment. Clinical trials have demonstrated that antithrombotic therapy reduces the risk for recurrent myocardial infarction and cardiovascular death. Antiplatelet drugs and anticoagulants interfere with haemostasis and thus bleeding is a major risk factor of these drugs. The benefit of antithrombotic therapy must therefore be carefully balanced with the risk of bleeding and other potential adverse reactions of these drugs. However, to date there is no firm evidence that dosage adaptation of aspirin or clopidogrel according to platelet aggregation testing translates directly into any clinical benefit. Resistance to antithrombotic drugs is a serious problem because these patients are at a higher risk of myocardial infarction, stroke and cardiovascular death. It has most recently been demonstrated that resistance to clopidogrel is at least in part caused by polymorphism of CYP2C19. Clinical trials have also demonstrated that optimal benefit in different settings depends unequivocally on the meticulous choice of the various drugs. Thus, profound knowledge of the clinical pharmacological profiles of the different antithrombotic drugs is indispensable for successful treatment.

One-year clinical outcome after abciximab bolus-only compared with abciximab bolus and 12-hour infusion in the Randomized EArly Discharge after Transradial Stenting of CoronarY Arteries (EASY) Study

BACKGROUND

Long-term clinical follow-up has shown a significant benefit after percutaneous coronary intervention (PCI) for abciximab bolus followed by 12-hour infusion over placebo or bolus-only. With contemporary techniques and clopidogrel pretreatment, it is unknown whether the 12-hour infusion is still associated with a clinical benefit. The purpose of this study is to compare 6- and 12-month clinical outcomes in patients treated after PCI with abciximab bolus-only and abciximab bolus followed by 12-hour infusion.

METHODS

After a bolus of abciximab (0.25 mg/kg) and uncomplicated transradial coronary stenting, 1,005 patients were randomized either to same-day discharge and no infusion of abciximab (bolus-only group, n = 504) or to overnight hospitalization and 12 hours (0.125 microg/[kg min]) of abciximab infusion (bolus + infusion group, n = 501). The rate of major adverse cardiovascular events (MACE) was evaluated at 30 days, 6 months, and 12 months.

RESULTS

At 30 days, the rate of MACE including death, myocardial infarction, and target vessel revascularization was similar in the 2 groups: 1.4% in the bolus-only group versus 1.8% in the bolus + infusion group (P = .63). At 6 months, the MACE rate was 5.6% in the 2 randomized groups. At 12 months, the MACE rate was also similar in both groups: 8.7% in the bolus-only group and 9.2% in the bolus + infusion group (hazard ratio 0.97, 95% CI 0.79-1.20, P = .80). Similar efficacy was also observed in several subgroups including higher-risk patients such as those with elevated troponin T before PCI.

CONCLUSIONS

In patients pretreated with clopidogrel and undergoing uncomplicated coronary artery stenting, there is no difference in the 6- and 12-month outcomes between patients treated with abciximab bolus-only versus those treated with bolus + infusion, a finding consistent with the initial 30-day outcomes.

Pharmacological antithrombotic adjuncts to percutaneous coronary intervention

Stent thrombosis is the major cause of early adverse events during percutaneous coronary intervention. Its incidence has fallen considerably in recent years, principally due to the introduction of effective antithrombotic therapies. The selection of an appropriate antithrombotic regimen is critical in achieving a balance between reducing ischaemic events and minimising bleeding complications in patients undergoing percutaneous coronary intervention. In this article, evidence for the role of antiplatelet and anticoagulant therapies is discussed, including the thienopyridines, glycoprotein IIb/IIIa receptor antagonists, direct thrombin inhibitors and pentasaccharides.

Current strategies with high-dose tirofiban

The glycoprotein (GP) IIb/IIIa receptor is a platelet-specific adhesion receptor that mediates the formation of platelet aggregates. Pharmacologic blockade of the receptor is associated with a reduction in major cardiovascular adverse events after percutaneous coronary interventions and in the setting of acute coronary syndromes. Three intravenous GP IIb/IIIa receptor inhibitors are available: abciximab, tirofiban and eptifibatide. Tirofiban is a small, synthetic non-peptide, competitive GP IIb/IIIa antagonist with high specificity and high affinity for the GP IIb/IIIa receptor. In a head-to-head comparison, tirofiban 10-microg/kg bolus followed by a 0.15-microg/kg/min infusion was found to be inferior to standard dose of abciximab in patients undergoing percutaneous coronary intervention. Insufficient platelet inhibition with low-dose tirofiban may likely explain these results. Subsequently, a high-bolus dose of tirofiban (25 microg/kg bolus) followed by standard infusion was tested and evidence suggest that in this dosing tirofiban may be as effective as abciximab and have a comparable safety profile. Therefore, high-bolus dose tirofiban may be an appealing and cost-effective alternative to abciximab. However, further testing is warranted given the short follow up and limited statistical power of the available data.