Ticagrelor for Asian patients with acute coronary syndrome in real-world practice: A systematic review and meta-analysis of observational studies

Progress in the clinical effects and adverse reactions of ticagrelor

BACKGROUND

Ticagrelor is a novel receptor antagonist that selectively binds to the P2Y12 receptor, thereby inhibiting adenosine diphosphate (ADP)-mediated platelet aggregation. Compared to clopidogrel, ticagrelor has the advantages of a fast onset, potent effects, and a reversible platelet inhibition function, which make this drug clinically suitable for treating acute coronary syndrome (ACS), especially acute ST-segment elevation myocardial infarction (STEMI).

OBJECTIVE

This review was performed to determine the basic characteristics, clinical effects, and adverse reactions of ticagrelor.

METHODS

Relevant trials and reports were obtained from the MEDLINE, Embase, and Cochrane Library databases.

RESULTS

Ticagrelor is rapidly absorbed by the body after oral administration, exhibits inherent activity without requiring metabolic activation, and binds reversibly to the P2Y12 receptor. Ticagrelor has been recommended in ACS treatment guidelines worldwide due to its advantageous pharmacological properties and significant clinical benefits. Ticagrelor inhibits platelet aggregation, inhibits inflammatory response, enhances adenosine function, and has cardioprotective effects. However, ticagrelor also causes adverse reactions such as bleeding tendency, dyspnea, ventricular pause, gout, kidney damage, and thrombotic thrombocytopenic purpura in clinical treatment. Therefore, it is necessary to pay attention to risk assessments when using ticagrelor.

CONCLUSION

Ticagrelor is a promising drug for the effective treatment of ACS. When using ticagrelor, individualized treatment should be provided based on the specific conditions of the patients to avoid serious adverse events.

Integrating Mechanisms in Thrombotic Peripheral Arterial Disease

Peripheral arterial disease (PAD), a manifestation of systemic atherosclerosis, is underdiagnosed in the general population. Despite the extensive research performed to unravel its pathophysiology, inadequate knowledge exists, thus preventing the development of new treatments. This review aims to highlight the essential elements of atherosclerosis contributing to the pathophysiology of PAD. Furthermore, emphasis will be placed on the role of thrombo-inflammation, with particular focus on platelet and coagulation activation as well as cell-cell interactions. Additional insight will be then discussed to reveal the contribution of hypercoagulability to the development of vascular diseases such as PAD. Lastly, the current antithrombotic treatments will be discussed, and light will be shed on promising new targets aiming to aid the development of new treatments.

Efficacy and Safety of Clopidogrel Versus Ticagrelor as Part of Dual Antiplatelet Therapy in Acute Coronary Syndrome-A Systematic Review and Meta-analysis

ABSTRACT

The efficacy and safety of clopidogrel compared with ticagrelor as part of dual antiplatelet therapy in patients, and in older patients, with acute coronary syndrome is reviewed. PubMed, Embase, the Cochrane Library, MEDLINE, and HTA databases were searched (September 2, 2020) for randomized controlled trials (RCTs). Pooled risk differences (clopidogrel minus ticagrelor) were estimated using random-effects meta-analyses, and certainty of evidence was assessed according to Grading of Recommendations Assessment, Development, and Evaluation. In all, 29 RCTs were identified. The risk difference for all-cause mortality was 0.6% (-0.03% to 1.3%), cardiovascular (CV) mortality: 0.6% (95% confidence interval: 0.01% to 1.1%), myocardial infarction (MI): 0.9% (0.4% to 1.3%), stent thrombosis: 0.7% (0.4 to 1.1%), clinically significant bleeding: -1.9% (-3.7% to -0.2%), major bleeding: -0.9% (-1.6% to -0.1%), and dyspnea: -5.8% (-7.7% to -3.8%). In older patients, there were no differences between the comparison groups regarding all-cause mortality, CV mortality, and MI, whereas the risk of clinically significant bleeding and major bleeding was lower in the clopidogrel group, -5.9% (-11 to -0.9%, 1 RCT) and -2.4% (-4.4% to -0.3%), respectively. Compared with ticagrelor, clopidogrel may result in little or no difference regarding all-cause mortality. Although not evident in older patients, it cannot be excluded that clopidogrel may be slightly less efficient in reducing the risk of CV mortality and MI, whereas ticagrelor is probably more efficacious in reducing the risk of stent thrombosis. Clopidogrel results in a reduced risk of dyspnea and clinically significant bleeding and in older people probably in a reduced risk of major bleeding.

Risk of bleeding with ticagrelor in elderly patients over 75 years old: A systematic review and meta-analysis

BACKGROUND

Bleeding is an untoward outcome in the management of elderly patients with acute coronary syndrome (ACS). Although the potent oral P2Y12 inhibitor, ticagrelor is clinically beneficial, its association with bleeding events in elderly ACS patients (≥75 years) is poorly understood.

METHODS

We conducted a systematic search of 7 databases up to May 20, 2020 to identify studies which examined the risk of bleeding (defined according to each study) among elderly ACS patients (≥75 years) receiving ticagrelor compared to clopidogrel. Summary risk ratios (RR) were estimated using the random effects model.

RESULTS

Eight studies consisting of 5 observational studies and 3 randomized controlled trials involving 7032 elderly patients met the eligibility criteria. The mean age of the patients was 77.8 years, and the mean follow-up duration was 12 months. Overall, the pooled RRs showed higher risk of a bleeding event with ticagrelor compared to clopidogrel (RR 1.20, 95% confidence interval [95% CI] 1.03-1.40; P = .017). No statistically significant heterogeneity was observed among the studies (Q = 6.93; P = .44; I2 = 0). Also, pooled RRs did not show a higher risk of major bleeding (RR 1.32, 95% CI 0.91-1.92; P = .15) or minor bleeding (RR 1.09, 95% CI 0.76-1.58; P = .64) when comparing the ticagrelor to the clopidogrel group.

CONCLUSIONS

There is a 20% increased risk of a bleeding event in elderly ACS patients treated with ticagrelor compared to clopidogrel; for such patients, clopidogrel may be considered as an alternative agent to ticagrelor due to its lower risk of bleeding.

Use of ticagrelor and the risks of pneumonia and pneumonia-specific death in patients with non-acute coronary syndrome conditions: a population-based cohort study

Previous studies have shown that ticagrelor reduced risk of pneumonia in patients with acute coronary syndrome (ACS) compared to clopidogrel, however, its effect in patients with non-ACS cardiovascular diseases remains uncertain. The aim was to investigate the effect of ticagrelor on pneumonia and pneumonia-specific death compared to clopidogrel in non-ACS patients in Hong Kong. This was a population-based cohort study. We included consecutive patients using ticagrelor or clopidogrel admitted for non-ACS conditions in Hong Kong public hospitals from March 2012 to September 2019. Patients using both drugs were excluded. The outcomes of interest were incident pneumonia, all-cause death, and pneumonia-specific death. Multivariable survival analysis models were used to estimate the effects [hazard ratio (HR) and 95% confidence interval (CI)]. Propensity score matching, adjustment and weighting were performed as sensitivity analyses. In total, 90,154 patients were included (mean age 70.66 years, males 61.7%). The majority of them (97.2%) used clopidogrel. Ticagrelor was associated with a lower risk of incident pneumonia [0.59 (0.46-0.75)], all-cause death [0.83 (0.73-0.93)] and pneumonia-specific death [0.49 (0.36-0.67)]. Sensitivity analyses yielded similar results. Ticagrelor was associated with lower risk of all-cause death, pneumonia-specific death, and incident pneumonia in patients with non-ACS cardiovascular conditions, consistent with previous evidence in patients with ACS. This additional effect of anti-pneumonia should be considered when choosing a proper P2Y12 inhibitor for patients with high risk of pneumonia.

Risk of major adverse cardiovascular events of CYP2C19 loss-of-function genotype guided prasugrel/ticagrelor vs clopidogrel therapy for acute coronary syndrome patients undergoing percutaneous coronary intervention: a meta-analysis

The most effective antiplatelet treatments for acute coronary syndrome (ACS) patients carrying CYP2C19 loss-of-function (LoF) alleles undergoing percutaneous coronary intervention (PCI) is still debating and conflicting. It was aimed to compare the efficacy and safety endpoints for these patients treated with alternative P2Y12 receptor blockers (e.g. prasugrel or ticagrelor) against clopidogrel. Literature was searched in PubMed, Cochrane library, Synapse and 1000 Genomes databases following PRISMA guidelines for identifying relevant studies. Aggregated risk was estimated by RevMan software using either fixed/random-effects models where P values<0.05 (two-sided) were considered statistically significant. Nine studies comprising 16,132 ACS patients undergoing PCI were included in this analysis in which 2,746 and 2,640 patients were in the CYP2C19 LoF clopidogrel and alternatives treatment group, respectively. It was demonstrated that patients treated with prasugrel or ticagrelor significantly reduced the risk of MACEs (RR 0.58; 95% CI 0.45-0.76; P<0.0001) as compared to patients with clopidogrel where both groups carrying CYP2C19 LoF alleles. Subgroup analysis showed that prasugrel or ticagrelor significantly reduced the risk of cardiovascular death (RR 0.44; 95% CI: 0.25-0.74; P=0.002) and MI (RR 0.60; 95% CI: 0.44-0.81; P=0.0008) while other clinical outcomes were not found statistically significant between these two groups; stroke (RR 0.77; 95% CI: 0.43-1.38; P =0.39), stent thrombosis (RR 0.67; 95% CI: 0.38-1.18; P =0.17), unstable angina (RR 0.55; 95% CI: 0.13-2.33; P =0.42), revascularisation (RR 0.79; 95% CI: 0.28-2.24; P=0.66). Bleeding events were not found significantly different between these groups (RR 1.06; 95% CI: 0.88-1.28; P=0.55). Considering efficacy and safety, alternative antiplatelets (e.g. prasugrel or ticagrelor) may be regarded as better treatment option as compared to clopidogrel for ACS patients undergoing PCI.

Efficacy and Safety of Ticagrelor Compared to Clopidogrel in Patients Undergoing Percutaneous Coronary Intervention: A Meta-Analysis

BACKGROUND

The Platelet Inhibition and Patient Outcomes (PLATO) study found that ticagrelor plus aspirin (TA) was more effective than clopidogrel plus aspirin (CA), without an increase in the risk of massive bleeding in patients undergoing percutaneous coronary intervention (PCI). Data from other studies indicate that the conclusion is controversial with the results obtained by PLATO.

AIM

To investigate the efficacy and safety of TA, compared with CA, in patients with acute coronary syndrome (ACS) after PCI.

METHODS

A systematic literature search was performed in the MEDLINE, EMBASE, and Cochrane databases to compare the efficacy and safety of CA and TA treatment in patients with ACS after PCI. The endpoints were major adverse cardiac events (MACEs), death, stroke, myocardial infarction (MI), stent thrombosis, and bleeding events. The data analysis was performed using RevMan 5.3 software, and the odds ratios (ORs) and their 95% confidence intervals (CI) were calculated. The standards of reporting were in accordance with the PRISMA guidelines.

RESULTS

13 studies with a total of 58,062 patients were included in this study with a subgroup analysis of the European/American and Asian populations. In terms of effectiveness for MACEs, the European, American and Asian populations benefitted more from the TA treatment than the CA treatment (European and American populations, OR = 0.82, P = 0.0002; Asian, OR = 0.66, P < 0.0001; total, OR = 0.78, P < 0.0001). In terms of specific effectiveness indicators, such as stroke, MI, and stent thrombosis, the results of TA and CA groups in the European, American, and Asian populations were not consistent. In terms of safety, there was no statistical difference in total bleeding events between TA and CA treatments (OR = 1.19, P = 0.21). However, in the Asian population, the incidence of total bleeding events (OR = 1.52, P = 0.0004) in the TA group was higher than that in the CA group.

CONCLUSION

The TA treatment in the European and American populations is more beneficial and safer than CA treatment. However, although the Asian population has this benefit, the risk of bleeding is significantly increased as well, and antiplatelet drugs should be chosen carefully.