Network meta-analysis of prasugrel, ticagrelor, high- and standard-dose clopidogrel in patients scheduled for percutaneous coronary interventions

Effect of pretreatment with a P2Y12 inhibitor in patients with non-ST-elevation acute coronary syndrome: a systematic review and network meta-analysis

Background

This study aimed to systematically evaluate the effects of different types and doses of pretreatment with P2Y12 inhibitors in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI).

Methods

Electronic databases were searched for studies comparing pretreatment with different types and doses of P2Y12 inhibitors or comparison between P2Y12 inhibitor pretreatment and nonpretreatment. Electronic databases included the Cochrane Library, PubMed, EMBASE, and Web of Science. Literature was obtained from the establishment of each database until June 2022. The patients included in the study had pretreatment with P2Y12 inhibitors with long-term oral or loading doses, or conventional aspirin treatment (non-pretreatment). The primary endpoint was major adverse cardiac and cerebrovascular events (MACCEs) during follow-up within 30 days after PCI, which included determining the composite endpoints of cardiac death, myocardial infarction, ischemia-driven revascularization, and stroke. The safety endpoint was a major bleeding event.

Results

A total of 119,014 patients from 21 studies were enrolled, including 13 RCTs and eight observational studies. A total of six types of interventions were included-nonpretreatment (placebo), clopidogrel pretreatment, ticagrelor pretreatment, prasugrel pretreatment, double loading pretreatment (double loading dose of clopidogrel, ticagrelor, prasugrel) and P2Y12 inhibitors pretreatment (the included studies did not distinguish the types of P2Y12 inhibitors, including clopidogrel, ticagrelor, and prasugrel). The network meta-analysis results showed that compared to patients without pretreatment, patients receiving clopidogrel pretreatment (RR = 0.78, 95% CI:0.66, 0.91, P < 0.05) and double-loading pretreatment (RR = 0.62, 95% CI:0.41, 0.95, P < 0.05) had a lower incidence of MACCEs. There was no statistically significant difference in the incidence of major bleeding events among the six pretreatments (P > 0.05).

Conclusions

In patients with NSTE-ACS, pretreatment with P2Y12 inhibitors before percutaneous intervention reduced the incidence of recurrent ischemic events without increasing the risk of major bleeding after PCI compared with nonpretreatment. Clopidogrel or double loading dose P2Y12 inhibitors can be considered for the selection of pretreatment drugs.

Efficacy and Safety of Oral P2Y12 Inhibitors in Older Patients with Acute Coronary Syndrome: A Frequentist Network Meta-Analysis

BACKGROUND AND OBJECTIVE

Previous studies and meta-analyses have assessed optimal P2Y12 inhibitors following acute coronary syndrome in overall trial cohorts. However, there are insufficient data for the elderly cohort who are prone to high bleeding and ischemic events. We aimed to assess the optimal P2Y12 inhibitor therapy for older patients.

METHODS

PubMed, CENTRAL, and ClinicalTrials.gov databases were searched from inception through July 2020 to identify randomized controlled trials and propensity-matched observational studies including older patients (aged ≥ 65 years) that reported study-defined major adverse cardiovascular events (MACE) or major bleeding events. Outcomes at the mid-term follow-up were pooled to conduct a frequentist network meta-analysis.

RESULTS

Fourteen studies involving 12,953 older patients were included in our analysis. No significant difference was observed with MACE when all three P2Y12 inhibitors were compared with each other. Compared with clopidogrel, ticagrelor significantly increased the risk of major bleeding (risk ratio 1.35, 95% confidence interval 1.10-1.67) while prasugrel did not (risk ratio 1.02, 95% confidence interval 0.67-1.57). A sensitivity analysis of only randomized controlled trials yielded similar results for both MACE and major bleeding. The P score displayed prasugrel (0.5871) as the best treatment for MACE, while clopidogrel (0.7701) was the best P2Y12 inhibitor to decrease the risk of major bleeding. Ticagrelor (0.0634) was ranked the lowest because of an increased bleeding risk.

CONCLUSIONS

No significant difference is observed between the three P2Y12 inhibitors in study-defined MACE. Ranking by p-score suggests prasugrel as the best P2Y12 inhibitor to reduce the risk of MACE while clopidogrel is a better alternative than ticagrelor in older patients with acute coronary syndrome to decrease the risk of major bleeding. Because of a lack of individual-patient data analysis and heterogeneity amongst studies, future studies representing older patients with acute coronary syndrome are required to strengthen evidence regarding optimal antithrombotic therapy in this cohort.

Prasugrel Versus Ticagrelor in Patients with Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: a Systematic Review and Meta-analysis of Randomized Trials

PURPOSE

Dual antiplatelet therapy (DAPT) with aspirin and ticagrelor or prasugrel is the mainstay of treatment for patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). We aimed to systematically perform a head-to-head comparison of ticagrelor vs prasugrel in terms of efficacy and safety.

METHODS

We searched PubMed/Medline, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) for relevant published randomized controlled trials (RCTs). The primary outcome was adverse cardiovascular events and secondary outcome was bleeding events. A random-effects meta-analysis was used to obtain the pooled estimate of each outcome.

RESULTS

Nine RCTs with a total number of 6990 patients (3550 treated with prasugrel and 3481 treated with ticagrelor) were included. No significant difference between prasugrel and ticagrelor was observed in terms of mortality (OR 0.86, 95% CI 0.66 to 1.13, P = 0.28), major adverse cardiovascular events (MACEs) (OR 0.85, 95% CI 0.70 to 1.03, P = 0.10), non-fatal myocardial infarction (OR 0.78, 95% CI 0.57 to 1.06, P = 0.11), stroke (OR 1.02, 95% CI 0.60 to 1.72, P = 0.95), stent thrombosis (OR 0.76, 95% CI 0.47 to 1.21, P = 0.25), thrombolysis in myocardial infarction (TIMI) defined major (OR 0.94, 95% CI 0.19 to 4.67, P = 0.94), minor (OR 0.35, 95% CI 0.08 to 1.62, P = 0.18) and minimal (OR 0.48, 95% CI 0.19 to 1.18, P = 0.11) bleeding and Bleeding Academic Research Consortium (BARC) defined bleeding (OR 1.06, 95% CI 0.82 to 1.36, P = 0.68).

CONCLUSION

In patients with ACS undergoing PCI, both prasugrel and ticagrelor were associated with similar cardiovascular outcomes and adverse bleeding events.

One-Year Clinical Effectiveness Comparison of Prasugrel with Ticagrelor: Results from a Retrospective Observational Study using an Integrated Claims Database

BACKGROUND

No direct comparisons of ticagrelor and prasugrel with 1-year clinical follow-up have been reported.

OBJECTIVES

Our objective was to compare 1-year clinical outcomes among patients with acute coronary syndrome (ACS) managed with percutaneous coronary intervention (PCI) and treated with either ticagrelor or prasugrel in a real-world setting.

METHODS

This retrospective study included patients from a payer database who were aged ≥18 years and had ACS managed with PCI with no history of transient ischemic attack (TIA)/stroke. Data were propensity matched for prasugrel use with a 3:1 prasugrel:ticagrelor ratio. Post-discharge net adverse clinical event (NACE) rate at 1 year was evaluated for noninferiority using a pre-defined 20% margin. NACE was a composite of major adverse cardiovascular events (MACE) or rehospitalization for bleeding.

RESULTS

In total, 15,788 ACS-PCI patients were included (prasugrel 12,797; ticagrelor 2991). Prasugrel-treated patients were younger; less likely to be female, have prior myocardial infarction (MI), diabetes, or non-ST-segment elevation MI (NSTEMI); and more likely to have unstable angina (UA) than ticagrelor-treated patients. Prior to matching, NACE and MACE (P < 0.01) were lower, with no difference in bleeding with prasugrel compared with ticagrelor. After matching, there was no significant difference in baseline characteristics. Noninferiority was demonstrated for NACE, MACE, and bleeding between prasugrel and ticagrelor. NACE and MACE were significantly lower with prasugrel use, primarily driven by heart failure, with no significant difference in all-cause death, MI, UA, revascularization, TIA/stroke, or bleeding.

CONCLUSIONS

In this retrospective study, physicians preferentially used prasugrel rather than ticagrelor in younger ACS-PCI patients with lower risk of bleeding or comorbidities. After propensity matching, clinical outcomes associated with prasugrel were noninferior to those with ticagrelor.

Antithrombotic agents for secondary prevention after acute coronary syndromes: A systematic review and network meta-analysis

BACKGROUND

Nine oral antithrombotic medications currently available in the United States and Europe have been studied in clinical trials for secondary prevention of cardiac events following acute coronary syndrome (ACS). Few combinations of these medications have been directly compared, and studies have used multiple different comparator regimens.

METHODS

We performed a systematic review and network meta-analysis of randomized controlled trials evaluating one or more available oral antithrombotic therapies in patients with ACS or prior myocardial infarction (MI). Co-primary outcomes were all-cause and cardiovascular mortality compared with imputed placebo and aspirin monotherapy.

RESULTS

Forty-seven studies (196,057 subjects) met inclusion criteria and were included in the systematic review. Almost all studies tested either aspirin monotherapy compared with placebo or a combination of antithrombotic agents that included aspirin. Nearly all regimens reduced all-cause and cardiovascular mortality compared with imputed placebo. However, compared with imputed aspirin monotherapy, only combination therapy with aspirin plus ticagrelor was associated with lower cardiovascular mortality (OR 0.80, 95% CI 0.68-0.93), and triple therapy with aspirin, clopidogrel, and very low dose rivaroxaban was associated with lower all-cause mortality (OR 0.67, 95% CI 0.49-0.90). Major bleeding was increased 45-95% with dual antithrombotic therapy, and 2-6-fold with triple therapy.

CONCLUSION

Few combinations of antithrombotic therapy were associated with a reduction in mortality compared with aspirin monotherapy, highlighting the difficulty in clinical interpretation of composite ischemic endpoints. Future studies may need to focus on limiting the number of antithrombotic therapies tested in combination to best balance ischemic event reduction and bleeding.

Comparison of Clopidogrel With Prasugrel and Ticagrelor in Patients With Acute Coronary Syndrome: Clinical Outcomes From the National Cardiovascular Database ACTION Registry

Background

We aimed to compare the clinical outcomes of clopidogrel, prasugrel, and ticagrelor in clinical practice using the National Cardiovascular Database ACTION Registry^®. Treatment guidelines for patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention recommend dual antiplatelet therapy (DAPT) for 12 months. Few clinical trials have compared the safety and efficacy of clopidogrel with that of newer antiplatelet therapies.

Methods

A retrospective study of patients hospitalized for ACS at Cleveland Clinic Akron General was conducted. Data elements included detailed medical history and clinical outcomes during hospital stay. The primary outcome was a composite of major clinical events (cardiogenic shock, atrial fibrillation, ventricular fibrillation, ventricular tachycardia, heart failure, bleeding, and mechanical ventilation). The independent variable was the type of DAPT. Statistical analyses were performed using Chi-square and Mann-Whitney U tests. A post-hoc analysis was performed to compare between the antiplatelet drugs head-to-head.

Results

Subjects (n = 1,388) admitted between January 2011 and March 2016 with ACS and treated with clopidogrel, prasugrel, or ticagrelor were included in the study. Mean age was 65 ± 14 years and 46% had ST-segment elevation myocardial infarction. Prasugrel administration within 24 h was associated with a lower incidence of the composite outcome (P = 0.049), bleeding (P = 0.028), and heart failure (P = 0.002).

Conclusion

There was a significant difference between the type of antiplatelet drug and clinical outcomes in ACS patients who were treated with DAPT. Observations from current study may provide important information for prescribers in clinical decision-making.

Optimal Antiplatelet Therapy in ST-Segment Elevation Myocardial Infarction

Cardiovascular disease is the leading cause of death worldwide. Case-fatality rates for myocardial infarction (MI) in the United States have decreased over the past decades, in large part due to advances in the treatment of acute MI and secondary preventive therapy after MI. Antiplatelet therapy remains the cornerstone of treatment of MI. This article reviews the current state of antiplatelet therapy in ST-segment elevation MI.

Comparative Effectiveness and Safety Analysis of Dual Antiplatelet Therapies Within an Integrated Delivery System

BACKGROUND

Dual antiplatelet therapy is a mainstay of care for percutaneous coronary intervention (PCI) patients; however, uncertainty exists in real-world practice about comparative effectiveness and safety outcomes.

OBJECTIVE

To evaluate outcomes of different oral P2Y12 inhibitors in PCI patients.

METHODS

We retrospectively studied patients treated between July 1, 2010, and December 31, 2013. Patients received clopidogrel, prasugrel, ticagrelor, or more than 1 antiplatelet (switch) during PCI. Outcomes were evaluated for major adverse cardiovascular events (MACE) and bleeding at 1 year. Propensity score matching with Cox proportional hazards analysis was used to determine predictors of MACE and bleeding.

RESULTS

A total of 8127 patients were included: clopidogrel (n = 6872), prasugrel (n = 605), ticagrelor (n = 181), and switch (n = 469). Treatment with prasugrel was associated with the lowest risk of MACE using multivariate regression (odds ratio [OR] = 0.57; 95% CI = 0.36-0.92; P = 0.02). In the propensity score-matched analysis, only the prasugrel group was associated with a lower risk of MACE compared with the clopidogrel group. Clopidogrel was associated with the lowest risk of major bleeding using multivariate regression (OR = 0.64; 95% CI = 0.42-0.98; P = 0.042). Both ticagrelor (hazard ratio [HR] = 2.00; 95% CI = 1.11-3.59) and the switch groups (HR = 1.65; 95% CI = 1.09-2.50) were associated with a greater risk of major bleeding compared with clopidogrel. However, no differences were found in the propensity score-matched analysis.

CONCLUSIONS

Dual antiplatelet therapies differed in both MACE and bleeds in a real-world setting of PCI. Prasugrel was associated with fewer MACE, whereas clopidogrel had fewer major bleeding events.

Contemporary antiplatelet treatment in acute coronary syndrome patients undergoing percutaneous coronary intervention: 1-year outcomes from the GReek AntiPlatElet (GRAPE) Registry

Essentials The comparative efficacy and safety of antiplatelet agents in 'real life' is not clear. We recruited acute coronary syndrome patients receiving percutaneous coronary intervention. At 1-year follow-up, prasugrel offers better anti-ischemic protection than clopidogrel. Prasugrel and ticagrelor are accompanied by more frequent bleeding events.

SUMMARY

Background The comparative efficacy and safety of antiplatelet treatment outside randomized trials is not clear. Objectives To investigate long-term efficacy and safety in 'real-life' acute coronary syndrome (ACS) patients treated by percutaneous coronary intervention (PCI) with contemporary use of clopidogrel, prasugrel and ticagrelor. Methods In a prospective, observational, multicenter cohort study, 2047 patients were recruited into the GReek AntiPlatElet (GRAPE) Registry and were followed-up for 1 year for major adverse cardiovascular events (MACE, a composite of death, non-fatal myocardial infarction, urgent revascularization and stroke) and bleeding events (Bleeding Academic Research Consortium [BARC] classification). Results Exposure to clopidogrel, prasugrel and ticagrelor by PCI occurred in 959, 363 and 717 patients, respectively. After adjustment, the rate of MACE (primary outcome endpoint) was lower in prasugrel-treated patients (4.4%) than in clopidogrel-treated patients (10.1%) (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.30-0.91), although not significantly different between ticagrelor (6.8%) and clopidogrel groups (HR, 0.78; 95% CI, 0.54-1.12). Any type of BARC-classified bleeding (secondary outcome endpoint) was more frequent in prasugrel-treated patients (51.2%) than in clopidogrel-treated patients (37.6%) (HR, 1.61; 95% CI, 1.33-1.95) and more frequent in ticagrelor-treated patients (56.9%) than in clopidogrel-treated patients (HR, 1.81; 95% CI, 1.55-2.10). An adjusted comparison between prasugrel and ticagrelor-treated groups did not reveal differences in any outcome measure. After adjustment, the death rate was more reduced by novel agents in comparison with clopidogrel (2.9% vs. 6.2%). Conclusions In ACS/PCI patients, prasugrel offered better anti-ischemic protection than clopidogrel, whereas use of both novel agents is accompanied by more frequent bleeding events.

Prasugrel (Efient®) with percutaneous coronary intervention for treating acute coronary syndromes (review of TA182): systematic review and economic analysis

BACKGROUND

Acute coronary syndromes (ACSs) are life-threatening conditions associated with acute myocardial ischaemia. There are three main types of ACS: ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI) and unstable angina (UA). One treatment for ACS is percutaneous coronary intervention (PCI) plus adjunctive treatment with antiplatelet drugs. Dual therapy antiplatelet treatment [aspirin plus either prasugrel (Efient(®), Daiichi Sankyo Company Ltd UK/Eli Lilly and Company Ltd), clopidogrel or ticagrelor (Brilique(®), AstraZeneca)] is standard in UK clinical practice. Prasugrel is the focus of this review.

OBJECTIVES

The remit is to appraise the clinical effectiveness and cost-effectiveness of prasugrel within its licensed indication for the treatment of ACS with PCI and is a review of National Institute for Health and Care Excellence technology appraisal TA182.

DATA SOURCES

Four electronic databases (MEDLINE, EMBASE, The Cochrane Library, PubMed) were searched from database inception to June 2013 for randomised controlled trials (RCTs) and to August 2013 for economic evaluations comparing prasugrel with clopidogrel or ticagrelor in ACS patients undergoing PCI.

METHODS

Clinical outcomes included non-fatal and fatal cardiovascular (CV) events, adverse effects of treatment and health-related quality of life (HRQoL). Cost-effectiveness outcomes included incremental cost per life-year gained and incremental cost per quality-adjusted life-year (QALY) gained. An independent economic model assessed four mutually exclusive subgroups: ACS patients treated with PCI for STEMI and with and without diabetes mellitus and ACS patients treated with PCI for UA or NSTEMI and with and without diabetes mellitus.

RESULTS

No new RCTs were identified beyond that reported in TA182. TRITON-TIMI 38 (Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition with Prasugrel Thrombolysis in Myocardial Infarction 38) compared prasugrel with clopidogrel in ACS patients scheduled for PCI. No relevant economic evaluations were identified. Our analyses focused on a key subgroup of patients: those aged < 75 years who weighed > 60 kg (no previous stroke or transient ischaemic attack). For the primary composite end point (death from CV causes, non-fatal myocardial infarction or non-fatal stroke) statistically significantly fewer events occurred in the prasugrel arm (8.3%) than in the clopidogrel arm (11%). No statistically significant difference in major bleeding events was noted. However, there was a significant difference in favour of clopidogrel when major and minor bleeding events were combined (3.0 vs. 3.9%). No conclusions could be drawn regarding HRQoL. The results of sensitivity analyses confirmed that it is likely that, for all four ACS subgroups, within 5-10 years prasugrel is a cost-effective treatment option compared with clopidogrel at a willingness-to-pay threshold of £20,000 to £30,000 per QALY gained. At the full 40-year time horizon, all estimates are < £10,000 per QALY gained.

LIMITATIONS

Lack of data precluded a clinical comparison of prasugrel with ticagrelor; the comparative effectiveness of prasugrel compared with ticagrelor therefore remains unknown. The long-term modelling exercise is vulnerable to major assumptions about the continuation of early health outcome gains.

CONCLUSION

A key strength of the review is that it demonstrates the cost-effectiveness of prasugrel compared with clopidogrel using the generic price of clopidogrel. Although the report demonstrates the cost-effectiveness of prasugrel compared with clopidogrel at a threshold of £20,000 to £30,000 per QALY gained, the long-term modelling is vulnerable to major assumptions regarding long-term gains. Lack of data precluded a clinical comparison of prasugrel with ticagrelor; the comparative effectiveness of prasugrel compared with ticagrelor therefore remains unknown. Well-audited data are needed from a long-term UK clinical registry on defined ACS patient groups treated with PCI who receive prasugrel, ticagrelor and clopidogrel.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005047.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

"Real-World" Comparison of Prasugrel With Ticagrelor in Patients With Acute Coronary Syndrome Treated With Percutaneous Coronary Intervention in the United States

Objectives

The 30‐day clinical outcomes with prasugrel or ticagrelor were compared using a US payer database in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI).

Background

Prasugrel and ticagrelor demonstrated superior efficacy with increased non‐coronary artery bypass graft major bleeding compared with clopidogrel in randomized clinical trials. No direct randomized or observational studies have compared clinical outcomes between prasugrel and ticagrelor.

Methods

Patients hospitalized for ACS‐PCI between August 1, 2011 and April 30, 2013 and prescribed prasugrel or ticagrelor were selected. Drug treatment cohorts were propensity matched based upon demographic and clinical characteristics. The primary objective compared 30‐day net adverse clinical events (NACE) in prasugrel‐ and ticagrelor‐treated patients using a prespecified 20% noninferiority margin. Secondary objectives included comparisons of major adverse cardiovascular events (MACE) and major bleeding.

Results

Data were available for 16,098 patients (prasugrel, n = 13,134; ticagrelor, n = 2,964). In unmatched cohorts, prasugrel‐treated patients were younger with fewer comorbidities than ticagrelor‐treated patients, and 30‐day NACE rates were 5.6 and 9.3%, respectively (P < 0.001). Following propensity matching, NACE was noninferior (P < 0.001) and 22% lower in prasugrel‐treated than in ticagrelor‐treated patients (RR, 0.78; 95% CI, 0.64–0.94). A 30‐day adjusted MACE (RR, 0.80; 95% CI, 0.64–0.98) and major bleeding (RR, 0.65; 95% CI, 0.45–0.95) were also lower in prasugrel‐treated patients compared with ticagrelor‐treated patients.

Conclusions

In this “real‐world,” retrospective, observational study, physicians appear to preferentially use prasugrel in younger patients with lower risk of bleeding or comorbidities compared with ticagrelor. Following adjustment, clinical outcomes associated with prasugrel use appear as good, if not better, than those associated with ticagrelor in ACS‐PCI patients. © 2015 Wiley Periodicals, Inc.

Should dual antiplatelet therapy be used in patients following coronary artery bypass surgery? A meta-analysis of randomized controlled trials

BACKGROUND

We assessed the effectiveness of dual antiplatelet therapy (DAPT) post elective or urgent (i.e., post acute coronary syndrome [ACS]) coronary artery bypass graft surgery (CABG).

METHODS

We systematically searched MEDLINE, EMBASE, and the Cochrane Registry from inception to August 2015. Randomized controlled trials (RCTs) in adults undergoing CABG comparing either dual vs. single antiplatelet therapy or higher- vs. lower-intensity DAPT were identified.

RESULTS

Nine RCTs (n = 4,887) with up to 1y follow-up were included. Five RCTs enrolled patients post-elective CABG (n = 986). Two multi-centre RCTs enrolled ACS patients who subsequently underwent CABG (n = 2,155). These 7 RCTs compared clopidogrel plus aspirin to aspirin alone. Two other multi-centre RCTs reported on ACS patients who subsequently underwent CABG comparing higher intensity DAPT with either ticagrelor (n = 1,261) or prasugrel (n = 485) plus aspirin to clopidogrel plus aspirin. Post-operative anti-platelet therapy was started when chest tube bleeding was no longer significant, typically within 24-48 h. There were no differences in all-cause mortality in clopidogrel plus aspirin vs. aspirin RCTs; conversely, all-cause mortality was significantly lower in ticagrelor and prasugrel vs. clopidogrel RCTs (risk ratio[RR] 0.49, 95% confidence interval[CI] 0.33-0.71, p = 0.0002; 2 RCTs, n = 1695; I(2)  = 0%; interaction p < 0.01 compared to clopidogrel plus aspirin vs aspirin RCTs). There were no differences in myocardial infarctions, strokes, or composite outcomes. Overall, major bleeding was not significantly increased (RR 1.31, 95% CI 0.81-2.10, p = 0.27; 7 RCTs, n = 4500). There was heterogeneity (I(2)   = 42%) due almost entirely to higher bleeding reported for the prasugrel RCT which included mainly CABG-related major bleeding (RR 3.15, 95% CI 1.45-6.87, p = 0.004; 1 RCT, n = 437).

CONCLUSIONS

Most RCT data for DAPT post CABG is derived from subgroups of ACS patients in DAPT RCTs requiring CABG who resume DAPT post-operatively. Limited RCT data with heterogeneous trial designs suggest that higher intensity (prasugrel or ticagrelor) but not lower intensity (clopidogrel) DAPT is associated with an approximate 50% lower mortality in ACS patients who underwent CABG based on post-randomization subsets from single RCTs. Large prospective RCTs evaluating the use of DAPT post-CABG are warranted to provide more definitive guidance for clinicians.

One-year post-discharge resource utilization and treatment patterns of patients with acute coronary syndrome managed with percutaneous coronary intervention and treated with ticagrelor or prasugrel

OBJECTIVE

Our objective was to compare 1-year real-world healthcare resource utilization (HRU), associated charges, and antiplatelet treatment patterns among patients with acute coronary syndrome (ACS) managed with percutaneous coronary intervention (PCI) and treated with ticagrelor or prasugrel.

METHODS

Using the ProMetis-Lx database, adult ACS-PCI patients treated with ticagrelor or prasugrel post-discharge were identified between 1 August 2011 and 31 May 2013 and propensity matched to adjust for baseline differences.

RESULTS

Before matching, ticagrelor-treated patients (n = 2991) were older with increased baseline ischemic and bleeding risks compared with prasugrel-treated patients (n = 12,797). After matching, ticagrelor patients had higher all-cause HRU (2.5 vs. 2.4 per patient per month; P = 0.012) and cardiovascular (CV) HRU (0.4 vs. 0.3 per patient per month; P = 0.026), with the difference in CV rehospitalizations (17.7 vs. 15.7 %; P = 0.011) primarily driven by congestive heart failure (CHF) (4.9 vs. 3.8 %; P = 0.02). All-cause charges within 1 year did not significantly differ between groups ($US5456 vs. 4844 per patient per month; P = 0.37), but dyspnea-related total charges were significantly higher with ticagrelor ($US139 vs. 95 per patient per month; P = 0.005). Although infrequent, switching was slightly higher with ticagrelor (8.3 vs. 6.0 %; P < 0.001) at 1 year, and mean persistence was slightly longer with prasugrel (150 vs. 159 days; P = 0.002), with no significant difference in mean adherence (61 vs. 63 %; P = 0.17).

CONCLUSION

Overall monthly HRU was slightly lower with prasugrel than with ticagrelor, with no significant difference in bleeding HRU. Prasugrel was associated with slightly higher pharmacy charges, but lower dyspnea charges, resulting in no significant difference in total charges. Patients receiving prasugrel tended to use it for longer than those receiving ticagrelor as less switching occurred. These findings may aid decision making, but must be tempered due to inherent study limitations.

Meta-Analysis of Randomized Controlled Trials Comparing Risk of Major Adverse Cardiac Events and Bleeding in Patients With Prasugrel Versus Clopidogrel

The use of prasugrel in patients with coronary artery disease (CAD) has been associated with decreased major adverse cardiac events (MACEs) compared with clopidogrel but with an increased risk of bleeding. However, it remains unclear if the risks of bleeding outweigh those of MACEs in patients on prasugrel treatment. We systematically reviewed randomized controlled trials comparing prasugrel with clopidogrel in patients with CAD. We performed a literature search of PubMed, EMBASE, and Cochrane Central Register of Controlled Trial databases from inception to November 25, 2014, and reviewed the reference lists of retrieved articles. A comparative estimate was made for the combined rates of MACEs and bleeding from the same trials in the framework of this meta-analysis and expressed as odds ratios (ORs) and 95% confidence intervals (CIs) in both random- and fixed-effects models. Nine studies involving 25,214 patients were included in our meta-analysis. In both the random- and fixed-effects models, the risks of MACEs outweighed those of major bleeding (OR 7.48, 95% CI 3.75 to 14.94, p <0.0001, random effects) and of minor bleeding (OR 3.77, 95% CI 1.73 to 8.22, p = 0.009, random effects). Results were corroborated in a standard-dose clopidogrel subgroup analysis (OR 7.46, 95% CI 3.54 to 15.68, p <0.0001, and OR 6.44, 95% CI 2.80 to 14.80, p <0.0001, random effects, respectively). In conclusion, despite the increased risk of bleeding associated with prasugrel treatment compared with clopidogrel, the risk of MACEs far outweighed the risk of bleeding.

Comparison of healthcare resource utilization and costs in patients hospitalized for acute coronary syndrome managed with percutaneous coronary intervention and receiving prasugrel or ticagrelor

OBJECTIVE

To compare healthcare resource utilization (HCRU) and healthcare costs in patients with acute coronary syndrome (ACS) managed with percutaneous coronary intervention (PCI) and treated with prasugrel or ticagrelor.

METHODS

Hospital charge master data were used to identify ACS-PCI patients aged ≥ 18 years with ≥ 1 in-hospital claim for prasugrel or ticagrelor between August 1, 2011-April 30, 2013. Treatment groups were propensity matched for baseline and index hospitalization characteristics. HCRU and costs were assessed through 90-days post-discharge. Costs were determined based on hospital-specific cost-to-charge ratios and adjusted to 2013 US dollars.

RESULTS

Before matching, ticagrelor patients were older, more-often female, and had increased cardiovascular (CV) and bleeding risks compared with prasugrel patients. Propensity-matched length of index hospital stay (4.7 vs 4.9 days, p = 0.23) and risk for all-cause [30-day: relative risk (RR) = 0.86; 95% CI = 0.73-1.0; 90-day: RR = 0.90; 95% CI = 0.80-1.0, and CV-related (30-day: RR = 0.77; 95% CI = 0.59-1.0; 90-day: RR = 0.89; 95% CI = 0.73-1.1) re-hospitalizations did not significantly differ between prasugrel and ticagrelor, respectively. Compared to ticagrelor, the propensity-matched risk of re-hospitalization for myocardial infarction (MI) (30-day: RR = 0.39; 95% CI = 0.21-0.75; 90-day: RR = 0.53; 95% CI = 0.34-0.81) and an outpatient medical encounter for dyspnea (30-day: RR = 0.49; 95% CI = 0.33-0.74; 90-day: RR = 0.60; 95% CI = 0.46-0.80) were significantly lower for prasugrel patients, with no significant differences in bleeding encounters between groups (30-day: RR =  0.87; 95% CI = 0.54-1.40; 90-day: RR = 1.0; 95% CI = 0.71-1.50). Matched total healthcare costs were not significantly different between groups during the index hospitalization ($36,011 vs $37,247, p = 0.21), 30-days post-discharge ($2007 vs $2522, p = 0.48), 90-days post-discharge ($4564 vs $5242, p = 0.49), and aggregate of the index hospitalization through 90-day follow-up ($40,576 vs $42,494, p = 0.09) timeframes.

CONCLUSIONS

Re-hospitalization for MI and outpatient encounters for dyspnea were lower in prasugrel treated than in ticagrelor treated ACS-PCI patients up to 90-days post-index hospitalization discharge, with no difference in bleeding encounters or healthcare costs between the two populations. This data supports the utility of prasugrel in routine clinical practice. These findings should be considered within limitations of observational research.

Prasugrel and ticagrelor: is there a winner?

Clopidogrel is a prodrug that undergoes extensive enteric clearance and requires two-stage hepatic activation by cytochrome P450 (CYP) enzymes. This metabolic pathway is susceptible to genetic polymorphisms, resulting in a variable platelet inhibitory effect. A growing number of studies have linked poor antiplatelet response to clopidogrel to adverse clinical outcomes, particularly coronary ischemic events and stent thrombosis. This has prompted the development of new ADP receptor antagonists that inhibit platelets more effectively. Two of these agents, prasugrel and ticagrelor, have been investigated in two large randomized clinical trials, and both have shown superiority versus clopidogrel in reducing ischemic endpoints, with an increase in bleeding events, but a favorable final net clinical outcome. Since the publication of the main articles, several sub-analyses have been performed on the same data, and Guideline recommendations have largely endorsed these subgroup findings. Most clinicians have accepted the concept that we might consider approaching the patient differently, deserving a specific agent for each different settings. However, subgroup analyses of randomized trials are often post hoc, underpowered and prone to bias. Weighing efficacy and safety of the most commonly used antiplatelet agents will represent a clinical challenge over the next few years. Furthermore, individuals and organizations involved in formulary decisions will have to face economic constraints, also taking into account the availability of low-cost generic clopidogrel. In the following review, we have performed a critical appraisal of the current literature in order to outline lights and shadows on the most relevant clinical scenarios.

High-maintenance-dose clopidogrel in patients undergoing percutaneous coronary intervention: a systematic review and meta-analysis

Background

Despite routine use of clopidogrel, adverse cardiovascular events recur among some patients undergoing percutaneous coronary intervention (PCI). To optimize antiplatelet therapies, we performed a meta-analysis to quantify the efficacy of high versus standard-maintenance-dose clopidogrel in these patients.

Methods

Randomized controlled trials (RCTs) comparing high (>75 mg) and standard maintenance doses of clopidogrel in patients undergoing PCI were included. The primary efficacy and safety end-points were major adverse cardiovascular/cerebrovascular events (MACE/MACCE) and major bleeding. The secondary end-points were other ischemic and bleeding adverse effects. The pooled odds ratio (OR) for each outcome was estimated.

Results

14 RCTs with 4424 patients were included. Compared with standard-maintenance-dose clopidogrel, high-maintenance-dose clopidogrel significantly reduced the incidence of MACE/MACCE (OR 0.60; 95% CI 0.43 to 0.83), stent thrombosis (OR 0.56; 95% CI 0.32 to 0.99) and target vessel revascularization (OR 0.38; 95% CI 0.20 to 0.74), without significant decrease of the risk of cardiovascular death (OR 0.92; 95% CI 0.74 to 1.13) and myocardial infarction (OR 0.83; 95% CI 0.51 to 1.33). For safety outcomes, it did not significantly increase the risk of major bleeding (OR 0.73; 95% CI 0.41 to 1.32), minor bleeding (OR 1.29; 95% CI 1.00 to 1.66) and any bleeding (OR 1.14; 95% CI 0.91 to 1.43).

Conclusion

High-maintenance-dose clopidogrel reduces the recurrence of most ischemic events in patients post-PCI without increasing the risk of bleeding complications.

Platelet reactivity tests for assessing antiplatelet drug response: what the clinician needs to know

Antiplatelet therapy is a cornerstone in the treatment of cardiovascular disease to prevent ischemic events. Various tests have become clinically available to measure platelet function after antiplatelet treatment. A wide interpatient variability in the magnitude of platelet inhibition has been demonstrated in numerous studies, especially in response to clopidogrel. Several reasons including clinical, pharmacological and genetic factors have been identified. High on-clopidogrel platelet reactivity has been linked to adverse clinical outcome, in particular to stent thrombosis after percutaneous coronary interventions. New antiplatelet drugs including prasugrel and ticagrelor have been advocated to overcome the limitations of clopidogrel. Several studies addressed the concept of tailored antiplatelet treatment according to the results of platelet function testing. Within this review, we summarize the current status of personalized antiplatelet therapy for cardiovascular disease.

Advances in antiplatelet technologies to improve cardiovascular disease morbidity and mortality: a review of ticagrelor

Antiplatelet therapy is widely used with proven benefit for the prevention of further ischemic cardiac complications in patients with acute coronary syndrome. Treatment guidelines for acute coronary syndrome and percutaneous coronary intervention now recommend the use of oral antiplatelet agents including ticagrelor, prasugrel, or clopidogrel in combination with aspirin to comprise dual antiplatelet therapy for the prevention of recurrent ischemic events. The limitations of conventional antiplatelet therapy with clopidogrel or prasugrel include the potential for low response to clopidogrel identified through platelet reactivity or genetic testing, increased risk of bleeding with prasugrel, or slower return to normal platelet activity in patients who received either prasugrel or clopidogrel prior to emergent or planned surgical procedures. This review will discuss the pharmacokinetic and pharmacodynamic properties of ticagrelor in comparison to conventional P2Y12 receptor inhibitors and its utility in patients identified as low responders to clopidogrel. Completed clinical studies and substudies comparing ticagrelor to clopidogrel and ongoing clinical trials evaluating ticagrelor in acute coronary syndrome patients will also be reviewed.

A mixed treatment comparison meta-analysis of antibiotic treatments for bovine respiratory disease

In this publication we use mixed treatment comparison meta-analysis to compare the efficacy of antibiotic treatments for bovine respiratory disease in beef cattle. Studies were eligible for the meta-analysis if they were publically available and reported the assessment of antibiotic protocols registered for use in the United States (US) for bovine respiratory disease (BRD) in beef cattle and were conducted in North America. Three electronic databases, the proceedings of two bovine specific conferences, pharmaceutical company web sites and the US Food and Drug Administration website were searched to identify relevant trials. The network of evidence used in the analysis contained 194 trial arms from 93 trials. Of the 93 trials there were 8 with three arms. The network of evidence contained information for 12 antibiotics. The output from the analysis provided information about the risk ratio comparing all possible treatments for BRD including comparisons based only on indirect data. The output also included a relative ranking of the treatments and estimates of the probability that an antibiotic protocol was the worst treatment option.