Comparison of half- and standard-dose ticagrelor in Chinese patients with NSTE-ACS

Spontaneous delayed migration or shortening after pipeline embolization device treatment of intracranial aneurysm: incidence, management, and risk factors

BACKGROUND

Studies reporting spontaneous delayed migration or shortening (SDMS) after treatment with the Pipeline Embolization Device (PED) are limited. This study aimed to evaluate the incidence of SDMS after PED treatment, propose management strategies, and identify the risk factors contributing to its occurrence.

METHODS

We retrospectively reviewed consecutive patients with an intracranial aneurysm (IA) treated with PEDs at three institutions. SDMS was classified as type I or II based on whether the PED covered the aneurysm neck.

RESULTS

The total cohort comprised 790 patients. SDMS was identified in 24 (3.04%) patients. Eighteen of the 24 patients had type I SDMS and did not require retreatment, while the remaining six patients had type II SDMS and all received retreatment. Multivariate logistic regression showed that the difference between the proximal and distal parent artery diameters (DPAD) (adjusted OR 2.977; 95% CI 1.054 to 8.405; P=0.039) and device tortuosity index (DTI) (adjusted OR 8.059; 95% CI 2.867 to 23.428; P<0.001) were independent predictors of SDMS after PED treatment, while the difference in length (DL) (adjusted OR 0.841; 95% CI 0.738 to 0.958; P=0.009) and PED plus coiling (adjusted OR 0.288; 95% CI 0.106 to 0.785; P=0.015) were protective factors.

CONCLUSION

The incidence of SDMS after PED treatment of IA was 3.04%. For patients with type I SDMS with incomplete aneurysm occlusion we recommend continuous imaging follow-up while, for patients with type II SDMS, we recommend aggressive retreatment. The DPAD and DTI were independent risk predictors of SDMS after PED treatment, while the DL and PED plus coiling were protective factors.

An alternative reduced dose regimen of ticagrelor for neuroendovascular patients

OBJECTIVE

There is a growing use of ticagrelor in patients undergoing neuroendovascular procedures, especially those who demonstrate clopidogrel resistance. While multiple dosages are studied in the cardiology literature, the optimal dose for patients with neurological pathology has yet to be established. Here, we describe a single center experience involving 39 patients who underwent neuroendovascular procedures that then received an adjusted lower dose of ticagrelor.

METHODS

A retrospective chart review was performed between 2013 and 2017 for patients on dual anti-platelet therapy (DAPT) for either cervical or intracranial vascular pathologies, as well as stenting of the neurovasculature, including carotid arteries. Patients were placed on ticagrelor if their measured P2Y12 reaction units (PRU) responses to clopidogrel were outside the expected range in our center using the VerifyNow™ P2Y12 test. All patients were maintained on a dose of 45 mg twice daily except for one patient who received 22.5 mg twice daily. Responsiveness to ticagrelor were measured utilizing the VerifyNow™ P2Y12 test.

RESULTS

The mean number of days for follow-up post treatment initiation was 532 days. A total of 39 patients were included in the analysis. Of these, 8 patients (21%) received implantation of intracranial stents (5 patients received pipeline embolization devices, 1 patient received stent-assisted coiling, and 2 patients received intracranial stents for atherosclerotic disease). Fourteen patients (35%) received carotid angioplasty and stenting. Seventeen patients (44%) did not receive permanent implantation of a stent. All patients on the lower dose ticagrelor of 45 mg twice daily achieved responsiveness (i.e., PRU < 194). Hemorrhagic transformation of ischemic stroke occurred in one patient (2.5%). No other hemorrhagic complications were encountered. No thromboembolic events were recorded aside from one patient (2.5%) with intracranial atherosclerotic disease who had an ischemic event.

CONCLUSIONS

A lower dose of ticagrelor (45 mg twice daily) appears to be safe and effective in this small cohort of patients who are resistant to clopidogrel per P2Y12 testing and who have increased risk of ischemic or hemorrhagic strokes due to neurovascular pathologies and implants. Further randomized studies are required to confirm these findings.

The Plasma Concentration of Ticagrelor and Aspirin as a Predictor of Bleeding Complications in Chinese Acute Coronary Syndrome Patients With Dual Antiplatelet Therapy: A Prospective Observational Study

PURPOSE

This study evaluated the association among the plasma concentration of ticagrelor, ARC124910XX, aspirin, and salicylic acid with the risk of recent bleeding in patients with the acute coronary syndrome. To this end, we developed an accurate model to predict bleeding.

METHODS

A total of 84 patients included in this study cohort between May 2021 and November 2021. The risk factors were identified by univariate and multivariate analyses, and statistically significant risk factors identified in the multivariate analysis were included in the nomogram. We used the calibration curve and the receiver operating characteristic curve to verify the accuracy of the prediction model.

RESULTS

Multivariable logistic analysis showed that ticagrelor concentration (odds ratio [OR]: 2.47, 95% confidence interval [CI], 1.51-4.75, P = 0.002), ST-segment elevation acute myocardial infarction (OR: 32.2, 95% CI, 2.37-780, P = 0.016), and lipid-lowering drugs (OR: 11.52, 95% CI, 1.91-110, P = 0.015) were positively correlated with bleeding. However, angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker (OR: 0.04, 95% CI, 0.004-0.213, P < 0.001) was negatively correlated with bleeding. The receiver operating characteristic curve analysis showed that ticagrelor concentration and these factors together predict the occurrence of bleeding (area under receiver operating characteristic curve = 0.945, 95% CI, 0.896-0.994) and that ticagrelor concentration >694.90 ng/mL is the threshold of bleeding concentration (area under receiver operating characteristic curve = 0.696, 95% CI, 0.558-0.834).

CONCLUSION

In patients with acute coronary syndrome treated with dual antiplatelet therapy, ticagrelor concentration >694.90 ng/mL was an independent risk factor for bleeding (OR: 2.47, 95% CI, 1.51-4.75, P = 0.002), but ARC124910XX and salicylic acid concentration did not affect bleeding risk ( P > 0.05).

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.

A randomized non-inferiority study of low-dose and standard-dose ticagrelor after intervention for acute coronary syndrome: study protocol for the TIGER STUDY

Background

Current guidelines recommend that patients with acute coronary syndrome (ACS) who have successfully undergone percutaneous coronary intervention (PCI) should continue to use dual antiplatelet therapy (DAPT) for 12 months. The long-term use of standard-dose dual antiplatelet therapy will increase the risk of bleeding. An optimized antiplatelet strategy that can prevent ischemic events and reduce the risk of bleeding remains to be explored.

Methods

The study is a prospective, multicenter, randomized, open-label, controlled study involving 2090 patients from six clinical centers in China. Through the interactive web response system (IWRS), ACS patients undergoing successful PCI will be randomly divided into the low-dose ticagrelor group or the normal-dose ticagrelor group, after taking 100 mg aspirin and 90 mg ticagrelor bid for 1 week. The primary endpoint is a composite of cardiovascular death, non-fatal myocardial infarction, stent thrombosis, repeat revascularization, and stroke. The secondary endpoints are bleeding events of grade 2 or higher according to Bleeding Academic Research Consortium [BARC] criteria, cardiovascular death, acute myocardium infarction, and coronary revascularization at 1 year.

Discussion

Recent studies have confirmed that 90 mg ticagrelor alone can safely and effectively reduce bleeding without increasing ischemic events of patients with ACS after PCI. Compared with standard-dose DAPT, whether low-dose ticagrelor combined with aspirin can ensure the anti-ischemic effect while reducing the bleeding risk remains unclear in Chinese patients.

The TIGER study will be the first large-scale, multicenter study to compare the efficacy and safety of low-dose and standard-dose ticagrelor combined with aspirin in ACS patients 1 week after successful PCI.

Trial registration

Clinicaltrials.gov NCT04255602. Registered on 5 February 2020.

Effect of Adjusted Antiplatelet Therapy on Preventing Ischemic Events After Stenting for Intracranial Aneurysms

BACKGROUND AND PURPOSE

This study tests whether patients with unruptured intracranial aneurysm who underwent stent placement benefitted from platelet function monitoring-guided adjustment of antiplatelet therapy.

METHODS

We conducted a randomized, open-label, parallel group, assessor-blinded trial. Patients with unruptured intracranial aneurysm who underwent stent placement were assigned in a 1:1 ratio to receive either drug adjustment (patients who had high on-treatment platelet reactivity to antiplatelet therapy on the basis of platelet function monitoring [monitoring group]) or conventional therapy (without monitoring and drug adjustment [conventional group]). The second monitoring was performed 14 days after randomization in patients with drug adjustment. The primary outcome was the composite frequency of ischemic stroke, transient ischemic attack, stent thrombosis, urgent revascularization, and cerebrovascular death within 7 days after stent implantation. The safety outcome was the composite frequency of major, minor, or minimal bleeding within 1 month after stent implantation.

RESULTS

In total, 314 patients were included (n=157 per group). The primary combined outcome occurred in 19 patients (12.1%) in the conventional group and 8 patients (5.1%) in the monitoring group (hazard ratio, 0.39 [95% CI, 0.17-0.92]; P=0.03). Ischemic stroke occurred at a lower frequency in the monitoring group compared with that in the conventional group (4.5% versus 12.1%; hazard ratio, 0.34 [95% CI, 0.14-0.83]; P=0.01), which drove the overall primary combined outcome. The safety outcome occurred in the monitoring group (7.0%) and in the conventional group (1.9%; hazard ratio, 3.87 [95% CI, 1.06-14.14]; P=0.03). A significant difference was observed in the frequency of minor or minimal bleeding events between the two groups (monitoring group versus conventional group, 6.4% versus 1.3%; P=0.02) but not in the frequency of major bleeding events between the two groups.

CONCLUSIONS

Platelet function monitoring-guided antiplatelet therapy reduces thromboembolic events in patients with unruptured intracranial aneurysm after stent placement, significantly enhancing minor or minimal bleeding events but not major bleeding events. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03989557.

Analysis of individualized antiplatelet therapy for patients of acute coronary syndrome after percutaneous coronary intervention under the guidance of platelet function: A one-center retrospective cohort study

There is controversy in clinical application of antiplatelet drugs by monitoring platelet function. Therefore, we explored whether early and dynamic medication could bring better clinical outcomes for patients under the guidance of platelet function tests (PFT).In this retrospective cohort study, we analyzed the prognostic events of 1550 patients with acute coronary syndrome (ACS) at Tianjin People's Hospital in China. They received dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) from January 2017 to December 2018. The primary endpoint was based on the Bleeding Academic Research Consortium (BARC) 3 or 5 major bleeding. Secondary endpoints included MACCE (all-cause death, nonfatal myocardial infarction, stroke, stent thrombosis, and unplanned target vessel reconstruction) and BARC 1 to 2 minor bleeding. The endpoint events within 1 year after PCI were recorded. Patients were divided into a guided group and a control group according to the drug adjustment by PFT results. After the propensity scores matched, the end points of 2 groups were compared, and subgroup analysis was performed on major bleeding events.After propensity score matching, there were 511 cases in the guided group and the control group, respectively. The primary endpoint events occurred in 10 patients (1.96%) in the guided group and 23 patients (4.5%) in the control group (HR: 0.45; 95% CI, 0.21-0.95; P = .037). After the guided group adjusted drug doses, the risk of major bleeding was lower than standard DAPT of the control group. Although some patients in the guided group reduced doses earlier, the incidence of MACCE events did not increase in the guided group compared with the control group (4.89% vs 6.07%; P = .41). There was no statistical difference in BARC 1 to 2 minor bleeding (P = .22). Subgroup analysis showed that PFT was more effective in patients with diabetes and multivessel disease.Early observation of dynamic PFT in ACS patients after PCI can guide individualized antiplatelet therapy to reduce the risk of major bleeding without increasing the risk of ischemia.

Safety and efficacy of low-dose ticagrelor in Chinese patients with acute coronary syndrome undergoing percutaneous coronary intervention

It remains unclear whether low-dose ticagrelor offers better safety and similar efficacy for Asian patients with acute coronary syndromes (ACS). We aimed to compare the safety and effectiveness of low-dose ticagrelor vs standard-dose ticagrelor in Chinese patients with ACS undergoing percutaneous coronary intervention (PCI). In this observational cohort study, a total of 2110 ACS patients who were event-free at 3 months after the index PCI were divided into standard-dose ticagrelor (90 mg twice daily) (n = 1830) or low-dose ticagrelor (45 mg twice daily) (n = 280) on a background of aspirin 100 mg once daily for at least another 9 months. The primary end point was type 2, 3, or 5 bleeding according to the Bleeding Academic Research Consortium (BARC) criteria over a 1-year follow-up period post-PCI. Predictors of the primary end point were identified. Both Cox regression and propensity score matching analyses were used. The cumulative incidence of BARC type 2, 3, or 5 bleeding was lower in the low-dose ticagrelor group vs the standard-dose group either before (adjusted HR 0.24; 95% CI 0.07-0.77; p = .016) or after matching (HR 0.25; 95% CI 0.08-0.85; p = .026). A composite of cardiac death, myocardial infarction, or stroke was not significantly different between the two groups (0.4% vs 0.9%, respectively). By multivariate analysis, only low-dose ticagrelor was a protected predictor of BARC type 2, 3, or 5 bleeding either before (HR 0.28, 95% CI 0.09-0.89) or after matching (HR 0.24, 95% CI 0.07-0.82). A low-dose regimen of ticagrelor might provide better safety than standard-dose ticagrelor in Chinese patients with ACS undergoing PCI.

The effect of antiplatelet drug on coronary endothelial and microvascular function: comparison with ticagrelor and clopidogrel

BACKGROUND/AIMS

Coronary endothelial and microvascular function play important roles in cardiovascular disease. We aimed to evaluate the effect of ticagrelor on coronary artery function and tested the antiplatelet effect of low dose ticagrelor in East-Asian patients.

METHODS

Sixty-one consecutive patients with non-significant coronary disease were included in the study. Initially, patients were randomized in 1:1:1 ratio to receive drugs: ticagrelor 90 mg twice a day (bid; n = 22), ticagrelor 45 mg bid (n = 19) or clopidogrel 75 mg once a day (qd; n = 20) and then divided into two groups (ticagrelor vs clopidogrel) for evaluation of coronary artery function, and three groups for evaluation of antiplatelet function. Endothelial dysfunction was measured by coronary flow reserve (CFR), and changes in the levels of asymmetric dimethylarginine (ADMA), cluster of differentiation (CD) 40 ligand, and P-selectin. Microvascular function was evaluated as index of microvascular resistance (IMR). Platelet reactivity was assessed by VerifyNow P2Y12 assay.

RESULTS

The levels of CFR, ADMA, and CD 40 ligand were not different between the two groups. However, P-selectin was lower in the ticagrelor group compared with clopidogrel group. IMR was significantly lower in the ticagrelor group compared with clopidogrel group (median, 15.0 [interquartile range, 12.0 to 21.0] vs. 47.5 [23.0 to 67.5], p = 0.014). There was significant difference in platelet inhibition among the three groups (ticagrelor 90 mg bid vs. ticagrelor 45 mg bid vs. clopidogrel 75 mg qd; 85.57 ± 47.63 vs. 120.33 ± 51.09 vs. 256.42 ± 55.10, p < 0.001).

CONCLUSION

It is hypothesized that ticagrelor might ameliorate the coronary microvascular function. When compared with clopidogrel, low dose ticagrelor exhibited satisfactory antiplatelet effect in the present study.

Pharmacodynamic and clinical efficacy of reduced ticagrelor maintenance doses in patients with coronary artery disease

OBJECTIVE

An increasing body of data indicates that a reduction of ticagrelor maintenance dose (MD) in stabilized patients might improve ticagrelor's safety profile and adherence to the treatment. The aim of this review was to discuss the rationale and summarize the current pharmacodynamic and clinical outcomes-based evidence from reduced MD of ticagrelor in patients with coronary artery disease (CAD).

METHODS

A narrative systematic review based on a literature search using the PubMed database from its inception through to June 2020. A search strategy included a combination of relevant search terms regarding ticagrelor reduced MD. The pre-determined inclusion criteria were: (1) randomized or observational trials; (2) presentation of clinical or pharmacodynamic results; (3) evaluation of any ticagrelor MD below 90 mg BID in patients with CAD.

RESULTS

Studies evaluating the following ticagrelor reduced MD have been identified: 90 mg QD, 60 mg BID, 60 mg QD, 45 mg BID, 22.5 mg BID. Majority of trials assessing doses <60 mg BID were performed in Asian patients only. Antiplatelet effect of ticagrelor in CAD decreases with the dose, however even reduced MDs provide sufficient platelet inhibition, which is greater than in clopidogrel-treated patients. De-escalation of ticagrelor dose shows a propensity towards a reduced rate of bleeding and non-bleeding adverse events.

CONCLUSIONS

Ticagrelor doses below 90 mg BID generally show an acceptable profile of platelet inhibition. The number of studies reporting clinical outcomes in CAD patients receiving reduced MD of ticagrelor are limited, however available results indicate that in a stable setting this strategy offers improved safety with preserved efficacy in the prevention of thrombotic events.

Safety and feasibility of low-dose ticagrelor in patients with ST-segment elevation myocardial infarction

Background

Previous studies have confirmed the safety and feasibility of half‐dose ticagrelor in Chinese patients with acute coronary syndrome, but currently there is no plan for the use of ticagrelor for Chinese ST‐segment elevation myocardial infarction (STEMI) patients.

Hypothesis

It is safe and feasible of low‐dose ticagrelor in patients with STEMI.

Methods

The STEMI patients who were undergoing emergency intervention and taking ticagrelor were enrolled. Patients whose level of platelet aggregation rate (PAR) less than 30% after 7‐day treatment with standard‐dose ticagrelor were randomly divided into low‐dose group (LD group, 45 mg twice daily) and standard‐dose group (SD group, 90 mg twice daily). The changes of levels of platelet parameters were compared between the two groups. The incidence of major adverse cardiac events (MACE), bleeding events were compared between the two groups within 6 months of follow‐up.

Results

The levels of PAR in the SD group decreased compared with baseline, and was lower than those of LD group at the same time point. The levels of platelet distribution width in both groups decreased from the baseline values (all p < .05) at 1, 3, and 6 months after grouping treatment, but there was no significant difference between the two groups. The incidence of MACE was similar between the two groups of patients. There were decreasing trends in the incidences of minimal bleeding event, minor bleeding event, dyspnea, and gout in the LD group.

Conclusion

It is safe and feasible of low‐dose ticagrelor for patients with STEMI based on the monitoring of PAR.

Efficacy and safety of low dose ticagrelor in patients with acute coronary syndrome: a systematic review and meta-analysis

Our aim was to examine clinical trials, provide guidance to practitioners and estimate the efficacy and safety of two agents by comparing low dose ticagrelor with standard dose clopidogrel in patients with acute coronary syndrome. We systematically looked through Pubmed, Embase, the Cochrane Library, Wanfang data and CNKI for trials comparing low dose ticagrelor with standard dose clopidogrel for the treatment of patients with ACS since the database was created. The primary endpoint for efficacy was the rate of major adverse cardiac events (MACEs). The primary endpoint for safety was the rate of major bleeding events. We also evaluated platelet function between low dose ticagrelor and standard dose clopidogrel in ACS patients. From 6744 articles, 16 studies including 1629 patients met the inclusion criteria. In contrast with standard dose clopidogrel, low dose ticagrelor significantly reduced MACEs (OR 0.39, 95% CI 0.26, 0.58) and the difference was statistically significant (p<0.01). No difference was noted for major bleeding events (OR 1.16, 95% CI 0.43, 3.08) between the two agents (p=0.77). In addition, low dose ticagrelor showed lower platelet aggregation rate than clopidogrel (standardised mean difference (SMD) -0.68, 95% CI -0.83 to 0.53) (p<0.01). Platelet reaction units for low dose ticagrelor were much lower than those for standard dose clopidogrel (SMD -2.46, 95% CI -2.85 to -2.07) (p<0.01). In comparison with standard dose clopidogrel, low dose ticagrelor significantly lowered the incidence of MACEs, improved left ventricular ejection fraction, decreased left ventricular end diastolic dimension and did not expand the risk of major bleeding events or minor or minimal bleeding events in ACS patients with a considerable safety and efficacy profile. In addition, low dose ticagrelor was associated with dramatically lower platelet aggregation compared with standard dose clopidogrel.

The risk of dyspnea in patients treated with third-generation P2Y12 inhibitors compared with clopidogrel: a meta-analysis of randomized controlled trials

Background

Ticagrelor and prasugrel are two third-generation oral P2Y₁₂ inhibitors which are more commonly used in clinical practice. However, dyspnea has been consecutively reported in patients using third-generation oral P2Y₁₂ inhibitors. This study aims to compare the risk of dyspnea in patients treated with third-generation P2Y₁₂ inhibitors compared with clopidogrel.

Methods

We systematically searched the PubMed, Cochrane Central Register of Controlled Trials databases, ClinicalTrials.gov and Web of Science for randomized control trials (RCTs) comparing ticagrelor or prasugrel with clopidogrel until July 2019. The primary outcome was the incidence of dyspnea. The risk ratios (RR) and 95% confidence intervals (CI) were estimated using meta-analysis.

Results

We included 25 RCTs involving 63,484 patients in this meta-analysis, including 21 studies on ticagrelor and 4 studies on prasugrel. Compared to the clopidogrel group, third-generation oral P2Y₁₂ inhibitors were associated with an increased risk of dyspnea compared with clopidogrel (RR 2.15, 95% CI 1.59–2.92), which was consistent in the analysis of ticagrelor (RR 2.65, 95% CI 1.87–3.76). However, the adverse effect was not found among patients receiving prasugrel therapy (RR 1.03, 95% CI 0.86–1.22). The increased dyspnea risk of ticagrelor was consistent in subgroups with different follow-up durations (≤ 1 month RR 1.87, 95% CI 1.56–2.24; 1–6 months RR 4.19, 95% CI 1.99–8.86; > 6 months 2.45, 95% CI 1.13–5.34).

Conclusions

Ticagrelor has a higher risk of dyspnea than clopidogrel, which was not observed in patients using prasugrel.

Efficacy and safety of different ticagrelor regimens versus clopidogrel in patients with coronary artery disease: a retrospective multicenter study (SUPERIOR)

Current guidelines favor dual anti-platelet therapy with ticagrelor 90 mg BID (T90BID) over clopidogrel 75 mg QD (C75QD) in addition to aspirin for acute coronary syndrome. However, an increased risk of ticagrelor-related adverse events prompted the evaluation of low-dose regimens. This study (NCT03381742) retrospectively analyzed the data from 11 hospitals on 3,043 patients with coronary artery disease, who received C75QD, T90BID, ticagrelor 45 mg BID (T45BID), or ticagrelor 90 mg QD (T90QD). Compared with C75QD, both T45BID and T90QD showed significantly higher inhibition of platelet aggregation (P < .0001) and lower platelet-fibrin clot strength (P < .0001) induced by adenosine diphosphate. Furthermore, compared with T90BID, two low-dose regimens had a much lower minor bleeding rate and a significantly higher proportion of patients within the therapeutic window for P2Y₁₂ receptor reactivity. There were no significant differences between T45BID and T90QD in the trough plasma concentrations of ticagrelor and its active metabolite. Similar efficacy and safety outcomes were observed in the propensity score-matched analysis. In conclusion, the low-dose ticagrelor regimen, either T45BID or T90QD, may provide a more attractive benefit-risk profile than C75QD or T90BID.

Optimal management of coronary artery disease in cancer patients

Owing to early diagnosis and rapid development of treatments for cancers, the five-year survival rate of all cancer types has markedly improved worldwide. Over time, however, there has been an increase in the number of cancer patients who develop coronary artery disease (CAD) due to different causes. First, many risk factors are shared between cancer and CAD. Second, inflammation and oxidative stress are common underlying pathogeneses in both disorders. Lastly, cancer therapy can result in endothelial injury, coronary artery spasm, and coagulation, thereby increasing the risk of CAD. As more cancer patients are being diagnosed with CAD, specialized cardiac care should be established to minimize the cardiovascular mortality of cancer survivors.

Systematic review with meta-analysis: the risk of gastrointestinal bleeding in patients taking third-generation P2Y12 inhibitors compared with clopidogrel

BACKGROUND

Ticagrelor and prasugrel are third-generation oral P2Y₁₂ receptor antagonists with rapid onset and pronounced platelet inhibition. However, higher overall bleeding rates have been reported for these agents when compared with clopidogrel.

AIM

To compare the risk of gastrointestinal bleeding (GIB) among users of third-generation P2Y₁₂ inhibitors with clopidogrel.

METHODS

We systematically searched for published randomised controlled trials of ticagrelor or prasugrel versus clopidogrel until September 2018. The primary outcome was the risk of GIB among users of third-generation P2Y₁₂ inhibitors when compared to clopidogrel, expressed as risk ratio (RR) and 95% confidence interval (CI). The rates of non-coronary artery bypass graft (CABG) major bleeding, life-threatening bleeding, fatal bleeding, and intracranial bleeding were analysed as secondary outcomes.

RESULTS

Forty-one studies were included in the analysis of non-CABG major bleeding, of which 12 were included in the analysis of GIB including 58 678 patients. Third-generation P2Y₁₂ inhibitors were associated with higher risk of GIB as compared with clopidogrel (RR 1.28, 95% CI 1.13-1.46). The findings were consistent for upper (RR 1.32, 95% CI 1.05-1.67) and unspecified GIB (RR 1.25, 95% CI 1.01-1.53), but not lower GIB (RR 1.25, 95% CI 0.95-1.65). Subgroup analysis showed higher GIB risk in prasugrel studies (RR 1.40, 95% CI 1.10-1.77) than in ticagrelor studies (RR 1.15, 95% CI 0.94-1.39). Third-generation P2Y₁₂ inhibitors also increased the risk of non-CABG major bleeding (RR 1.18, 95% CI 1.08-1.28).

CONCLUSION

Third-generation P2Y₁₂ inhibitors were associated with increased risk of GIB and non-CABG major bleeding when compared with clopidogrel.

Evaluation of pharmacokinetic, pharmacodynamic, efficacy, and safety data of low-dose ticagrelor versus standard dose in East Asians: a systematic review

East Asians are prone to higher systemic exposure and increased risk of bleeding compared to other races after administration of antiplatelet agent(s). The aim of this systematic review was to compare and evaluate the appropriateness of a lower dose versus standard dose of ticagrelor in East Asians. A systematic search was conducted in PubMed, EMBASE, and Cochrane databases for studies comparing low versus standard doses of ticagrelor in East Asian populations; a total of seven studies were included in the review. Pharmacokinetic (PK), pharmacodynamic (PD), clinical efficacy, and safety data were collected. PK data demonstrated that the C_max and area under the curve (AUC) of ticagrelor increased dose-proportionally. PD data indicated that while the low dose of ticagrelor resulted in less antiplatelet activity in three of the five PD studies, in the other studies, there were no differences between low and standard doses. There were two clinical studies included in this review, which showed that the efficacy was similar between the low and standard doses, but both studies were limited by the number of patients included. While there were generally greater incidence of adverse events observed in the standard ticagrelor dose, the magnitude or actual difference between the two doses is difficult to determine due to lack of consistent data. In East Asians, the appropriateness of the low-dose ticagrelor cannot be determined based on the currently available evidence. Additional large-scale and longer duration studies are warranted.

Ticagrelor versus clopidogrel in East Asian patients with acute coronary syndrome: Systematic review and meta-analysis

BACKGROUND

Bleeding complications are associated with unfavorable outcomes in patients with acute coronary syndrome (ACS). Compared to Whites, several studies demonstrated a higher risk of bleeding in Asians who present with acute myocardial infarction. To date, the efficacy and safety of ticagrelor in East Asian population have not been well established.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials that compared ticagrelor and clopidogrel in East Asian patients with acute coronary syndrome (ACS). We systematically searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and ClinicalTrial.gov database.

RESULTS

Three randomized controlled trials, including a total of 1552 patients, met our inclusion criteria. Study countries included Japan, South Korea, and China. All studies defined primary efficacy endpoint and major bleeding events in accordance with the PLATO definition. Ticagrelor was associated with a numerically lower, albeit statistically nonsignificant, risk of primary efficacy endpoint defined as a composite of death from vascular causes, myocardial infarction, or stroke (odds ratio 0.84; 95% confidence interval 0.43-1.63; p = 0.60). Ticagrelor was associated with a significantly higher risk of PLATO-defined major bleeding compared to clopidogrel (odds ratio 1.52; 95% confidence interval 1.04-2.23; p = 0.03).

CONCLUSIONS

Our meta-analysis demonstrated that ticagrelor was associated with a higher risk of major bleeding compared to clopidogrel in East Asian patients with ACS. Further studies evaluating the role of ticagrelor in management of ACS in East Asian patients are warranted.

CYP2C19 genotype and adverse cardiovascular outcomes after stent implantation in clopidogrel-treated Asian populations: A systematic review and meta-analysis

The effect of CYP2C19 gene polymorphism on clinical outcomes of patients with coronary artery disease (CAD) treated with clopidogrel remains controversial. Ethnicity has been proposed to influence clopidogrel response following stent implantation in CAD patients with different CYP2C19 genotypes. Furthermore, Asian populations are reported to have a relatively greater prevalence of CYP2C19 loss-of-function (LOF) alleles. We aimed to evaluate the impact of CYP2C19 gene polymorphism on clinical outcomes in Asian populations who underwent percutaneous coronary interventions (PCI) and received clopidogrel therapy. We conducted a comprehensive search in PubMed, EMBASE, and Cochrane Library from their inceptions to January 20, 2017. Studies that reported clopidogrel therapy information, clinically relevant outcomes (adverse cardiovascular events, stent thrombosis and bleeding), and CYP2C19 genotypes among Asian populations were included. The primary endpoint was major adverse cardiovascular events (MACE), defined as a composite of cardiovascular death and myocardial infarction. The safety endpoint was any kind of bleeding. We retrieved 20 studies of 15056 patients reporting 1301 cardiovascular events. The primary analysis showed at least one CYP2C19 LOF allele (*2 and/or *3) carriers were at an increased risk of MACE compared with non-carriers (10.58% vs. 6.07%, OR: 1.99, 95% CI: 1.64 to 2.42, p < .001). Stent thrombosis (ST) was also more frequent in LOF allele carriers (2.22% vs. 0.44%, OR: 4.77, 95% CI: 2.84 to 8.01, p < .001). Inversely, the risk of bleeding was lower in LOF allele carriers (OR: 0.66, 95% CI: 0.46 to 0.96, p < .001). Subgroup analysis was performed to assess differences by high (600 mg) or routine (300 mg) loading dose of clopidogrel and by different nationalities. The risk of MACE in LOF allele carriers remained significantly higher even in high loading dose group (high loading dose: OR 1.72, 95% CI: 1.37 to 2.16, and routine loading dose: OR 2.22, 95% CI: 1.68 to 2.94, p for subgroup heterogeneity = 0.16). Subgroup analysis between three nationalities of China, Korea, and Japan demonstrated that the risk of MACE among Chinese LOF allele carriers was the greatest (OR: 2.28; 95% CI:1.91 to 2.73). In conclusion, among Asian populations with CAD undergoing stent implantation, CYP2C19 LOF allele carriers are at greater risk of adverse cardiovascular events and lower risk of bleeding compared with non-carriers. Genetic testing may be helpful for clinicians to personalize antiplatelet therapy especially in Asian population.

Higher Risk of Bleeding in Asians Presenting With ST-Segment Elevation Myocardial Infarction: Analysis of the National Inpatient Sample Database

Bleeding is a major complication in patients presenting with ST-segment elevation myocardial infarction (STEMI). Several studies suggested that Asians are more susceptible to bleeding when treated with antiplatelets, anticoagulants, and thrombolytic agents. In our study, we aimed to investigate the association between Asian ethnicity and bleeding events in patients who presented with STEMI. We analyzed the Nationwide Inpatient Sample database from 2002 to 2013 and identified patients hospitalized with a primary diagnosis of STEMI. We compared clinical outcomes between patients of Asian and white ethnicity. Primary outcome was inhospital major bleeding defined as a composite of intracranial hemorrhage and blood transfusions for bleeding events. After exclusions, an estimated 1 695 680 white and 46 563 Asian patients with STEMI were included in the analysis. Asian patients had a higher incidence of inhospital major bleeding (3.6% vs 2.2%, P < .001) without a significant difference in inhospital mortality (9.3% vs 8.7%, P = .06). Asian ethnicity was an independent predictor for major bleeding (estimated odds ratio: 1.32; 95% confidence interval: 1.16-1.51; P < .001). This increased risk of bleeding would warrant further investigation of optimal treatment strategies tailored for patients with STEMI of Asian ethnicity.

A Prospective, Randomized, Open-Label, Blinded, Endpoint Study Exploring Platelet Response to Half-Dose Prasugrel and Ticagrelor in Patients with the Acute Coronary Syndrome: HOPE-TAILOR Study

Background: The optimal dosing of novel oral P2Y12 receptor platelet inhibitors such as prasugrel or ticagrelor is unclear and especially challenging in East Asians. We hypothesize that half-dose prasugrel and ticagrelor may be sufficient for long-term maintenance management in Korean patients with the acute coronary syndrome (ACS) compared with conventional dosages. Design: HOPE-TAILOR (Half Dose of Prasugrel and Ticagrelor in Platelet Response after Acute Coronary Syndromes) is a prospective, randomized, open-label, blinded, endpoint (PROBE) single-center, clinical trial. A total of 100 patients with ACS undergoing drug-eluting stent implantation will be randomly assigned to prasugrel, ticagrelor, or clopidogrel, and the patients in each treatment group will receive 1-month therapy with 100 mg q.d. aspirin plus prasugrel 10 mg q.d., ticagrelor 90 mg b.i.d., or clopidogrel 75 mg q.d., followed by half-dose prasugrel 5 mg q.d. or ticagrelor 45 mg b.i.d. for maintenance treatment but without clopidogrel dose reduction. The primary endpoint will be optimal platelet reactivity 3 months after coronary intervention, defined by VerifyNow Analyzer (PRU: 85-208) and vasodilator-stimulated phosphoprotein P2Y12 flow cytometry assay (platelet reactivity indices: 16-50%). Clinical outcomes will also be assessed, including major efficacy (composite of cardiac death, nonfatal myocardial infarction, repeat revascularization, or stroke) and safety (bleeding ≥2 according to the Bleeding Academic Research Consortium). Conclusion: HOPE-TAILOR is a prospective, randomized, open-label, blinded, endpoint study to explore the efficacy and safety of novel P2Y12 receptor inhibitors administered orally at half the dose in Korean patients with ACS. The results will be available late in 2017.