Guided Anti-P2Y12 Therapy in Patients Undergoing PCI: Three Systematic Reviews with Meta-analyses of Randomized Controlled Trials with Homogeneous Design

BACKGROUND

 The value of guided therapy (GT) with anti-P2Y12 drugs in percutaneous coronary intervention (PCI) is unclear. Meta-analyses lumped together randomized controlled trials (RCTs) with heterogeneous designs, comparing either genotype-GT or platelet function test (PFT)-GT with unguided therapy. Some meta-analysis also included RCTs that did not explore GT, but included the effects of switching patients with high on-treatment platelet reactivity (HTPR) to alternative therapies (HTPR-Therapy). We performed three distinct systematic reviews/meta-analyses, each exploring only RCTs with homogeneous design.

METHODS

 MEDLINE, Embase, and Central databases were searched for RCTs testing genotype-GT, PFT-GT, or HTPR-Therapy in PCI-treated patients, through October 1, 2022. Two reviewers extracted the data. Risk ratios (RRs) (95% confidence intervals) were calculated. Primary outcomes were major bleedings (MBs) and major adverse cardiovascular events (MACE).

RESULTS

 In seven genotype-GT RCTs, RRs were: MB, 1.06 (0.73-1.54; p = 0.76); MACE, 0.65 (0.47-0.91; p = 0.01), but significant risk reduction was observed in RCTs performed in China (0.30, 0.16-0.54; p < 0.0001) and not elsewhere (0.75, 0.48-1.18; p = 0.21). In six PFT-GT RCTs, RRs were: MB, 0.91 (0.64-1.28, p = 0.58); MACE, 0.82 (0.56-1.19; p = 0.30): 0.62 (0.42-0.93; p = 0.02) in China, 1.08 (0.82-1.41; p = 0.53) elsewhere. In eight HTPR-Therapy RCTs, RRs were: MB, 0.71 (0.41-1.23; p = 0.22); MACE, 0.57 (0.44-0.75; p < 0.0001): 0.56 (0.43-0.74, p < 0.0001) in China, 0.58 (0.27-1.23, p = 0.16) elsewhere.

CONCLUSION

 No GT strategy affected MB. Overall, genotype-GT but not PFT-GT reduced MACE. However, genotype-GT and PFT-GT reduced MACE in China, but not elsewhere. PFT-GT performed poorly compared to HTPR-Therapy, likely due to inaccurate identification of HTPR patients by PFT.

Racial differences in P2Y12 inhibitor responsiveness in patients undergoing neuro-endovascular procedures: A cohort from the Middle East

BACKGROUND

Data on P2Y12 inhibitors responsiveness from the middle east is scarce. We sought to investigate patient responsiveness to P2Y12 inhibitors within a cohort of major races that characterize the UAE population. The secondary objective was to assess risk factors for hyper and hypo-responsiveness in this population.

METHODS

We conducted a cross-sectional study on adults who received either clopidogrel or ticagrelor treatments and had platelet responsiveness testing before undergoing neuro-endovascular interventions at our quaternary care hospital between March 2015 and April 2019.

RESULTS

During the study period, 249 subjects met the inclusion criteria. Overall, 17.3 % were hyper-responsive and 25.7 % were hypo-responsive to P2Y12 inhibitors. When comparing between the P2Y12 inhibitors, rates of hyper-responsiveness were significantly higher to ticagrelor when compared to clopidogrel (11 versus 6 %, p = 0.02 respectively). Contrarily, hypo-responsiveness rates were significantly higher in clopidogrel treated patients compared to their ticagrelor treated counterparts (23 versus 2 %, p < .001 respectively). Patients of Middle-Eastern origin showed a significantly higher rate of hypo-responsiveness to both clopidogrel and ticagrelor when compared to other races (41.1 % and 26.7 %, P < 0.001 respectively). Asians showed the highest rates of hyper-responsiveness for both agents. Multivariate logistic regression analysis showed that proton pump inhibitors and statin combination, (OR: 6.39, 95 %CI [1.60, 25.392]), and Middle East vs. Indian subcontinent patients (OR: 4.67, 95 %CI [1.79-12.14]) were independent predictors of hypo-responsiveness to both P2Y12 inhibitors.

CONCLUSION

This study demonstrated a high rate of hypo-responsiveness to P2Y12 inhibitors in a UAE cohort of patients undergoing neuro-endovascular procedures. In addition, therapeutic responsiveness to P2Y12 inhibitors varied markedly based on the racial background. Future larger studies are needed to evaluate genetic variations that may contribute to this rate of hypo-responsiveness in our population.

Low-dose prasugrel versus standard-dose ticagrelor in east Asian patients with acute coronary syndrome

Low-dose prasugrel demonstrated a similar effectiveness profile to clopidogrel in East Asian ACS patients, but its comparison with another new-generation potent P2Y12 inhibitor, ticagrelor, remains unclear. To compare the effectiveness and safety of low-dose prasugrel against those of standard-dose ticagrelor in East Asian patients with ACS. This retrospective cohort study used Taiwan's National Health and Welfare Database. This study included ACS patients who underwent percutaneous coronary intervention and, at discharge between January 1, 2018 and December 31, 2020, were prescribed with low-dose prasugrel plus aspirin or standard-dose ticagrelor plus aspirin. Stabilized inverse probability of treatment weighting was used to balance the covariates across these two groups. The primary effectiveness outcome was a composite of acute myocardial infarction, ischemic stroke, and cardiovascular death; the secondary effectiveness outcome was each of the individual components of the primary outcome, transient ischemic attack, and repeat revascularization. The primary safety outcome was a composite of intracranial hemorrhage and gastrointestinal bleeding, and the two secondary safety outcomes were intracranial hemorrhage and gastrointestinal bleeding. A total of 24,807 patients were included in this study. Among them, 1,493 were low-dose prasugrel users and 23,314 were standard-dose ticagrelor users. No significant differences were found in primary effectiveness [HR: 0.97 (0.74-1.28)] or primary safety outcomes [HR: 1.22 (0.73-2.01)] between the two study groups. For East Asian patients with ACS, low-dose prasugrel provides comparable effectiveness without increasing bleeding risk compared to standard-dose ticagrelor. Low-dose prasugrel may be an appropriate alternative for East Asian populations.

Antiplatelet Treatment Preferences of a Group of Cardiologists from Türkiye: A Survey Research Study

OBJECTIVE

Deciding on the optimal duration of dual antiplatelet treatment (DAPT) remains a complex decision. This survey aims to explore the preferences for antiplatelet therapy and the daily routine regarding DAPT duration in coronary artery disease among a group of cardiologists in Türkiye.

METHOD

Using an online questionnaire with 38 questions, the preferences of 314 cardiologists were collected. Qualitative descriptive characteristics of the answers received from the participants were examined.

RESULTS

Participating cardiologists mostly worked in training and research hospitals (51.59%) and university hospitals (21.66%). Participants primarily favored ticagrelor in patients undergoing PCI with a diagnosis of STEMI and NSTE-ACS (69.75% and 55.73% respectively). Clopidogrel was the most preferred P2Y12 treatment in patients with chronic coronary syndrome (CCS) after PCI (94.90%). Pre-treatment with a loading dose of a P2Y12 receptor inhibitor was administered to 57.01% of patients with NSTE-ACS, irrespective of the planned treatment strategy. In NSTE-ACS patients with low bleeding risk treated with PCI, 83.12% of participants recommended DAPT for 12 months and 14.65% for >12 months. In high-bleeding-risk NSTE-ACS patients treated with PCI, DAPT durations of six months (74.52%), three months (19.75%), and one month (5.73%) were chosen. Among CCS patients treated with PCI without an increased risk of bleeding, 12 months of DAPT was preferred by 68.15% of participants. Most participants (70.70%) were switching to a more potent P2Y12 receptor inhibitor therapy in emergency department clopidogrel-loaded patients with ACS.

CONCLUSION

The aim of this survey to capture a snapshot of the preferences of a group of cardiologists in Türkiye regarding DAPT treatment and duration. The responses were both in accordance and in conflict with the current guidelines.

Aspirin-free antiplatelet strategies after percutaneous coronary interventions

Dual antiplatelet therapy (DAPT) with aspirin and a platelet P2Y12 receptor inhibitor is the standard antithrombotic treatment after percutaneous coronary interventions (PCI). Several trials have challenged guideline-recommended DAPT after PCI by testing the relative clinical effect of an aspirin-free antiplatelet approach-consisting of P2Y12 inhibitor monotherapy after a short course (mostly 1-3 months) of DAPT-among patients undergoing PCI without a concomitant indication for oral anticoagulation (OAC). Overall, these studies have shown P2Y12 inhibitor monotherapy after short DAPT to be associated with a significant reduction in the risk of bleeding without an increase in thrombotic or ischaemic events compared with continued DAPT. Moreover, the effects of the P2Y12 inhibitor monotherapy without prior DAPT or following a very short course of DAPT after PCI are being investigated in emerging studies, of which one has recently reported unfavourable efficacy results associated with the aspirin-free approach compared with conventional DAPT. Finally, P2Y12 inhibitor alone has been compared with aspirin alone as chronic therapy after DAPT discontinuation, thus challenging the historical role of aspirin as a standard of care for secondary prevention following PCI. A thorough understanding of study designs, populations, treatments, results, and limitations of trials testing P2Y12 inhibitor monotherapy vs. DAPT or vs. aspirin is required to consider adopting this treatment in clinical practice. This review addresses the use of aspirin-free antiplatelet strategies among patients undergoing PCI without a concomitant indication for OAC, providing an overview of clinical evidence, guideline indications, practical implications, ongoing issues, and future perspectives.

Platelet P2Y12 signalling pathway in the dysregulated immune response during sepsis

Sepsis is a complicated pathological condition in response to severe infection. It is characterized by a strong systemic inflammatory response, where multiple components of the immune system are involved. Currently, there is no treatment for sepsis. Blood platelets are known for their role in haemostasis, but they also participate in inflammation through cell-cell interaction and the secretion of inflammatory mediators. Interestingly, an increase in platelet activation, secretion, and aggregation with other immune cells (such as monocytes, T-lymphocytes and neutrophils) has been detected in septic patients. Therefore, antiplatelet therapy in terms of P2Y12 antagonists has been evaluated as a possible treatment for sepis. It was found that blocking P2Y12 receptors decreased platelet marker expression and limited attachment to immune cells in some studies, but not in others. This review addresses the role of platelets in sepsis and discusses whether antagonizing P2Y12 signalling pathways can alter the disease outcome. Challenges in studying P2Y12 antagonists in sepsis also are discussed. LINKED ARTICLES: This article is part of a themed issue on Platelet purinergic receptor and non-thrombotic disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.4/issuetoc.

P2Y12 Inhibitor Loading Time Before Elective PCI and the Prevention of Myocardial Necrosis

BACKGROUND

There are dated and conflicting data about the optimal timing of initiation of P2Y12 inhibitors in elective percutaneous coronary intervention (PCI). Peri-PCI myocardial necrosis is associated with poor outcomes. We aimed to assess the impact of the P2Y12 inhibitor loading time on periprocedural myocardial necrosis in the population of the randomized Assessment of Loading With the P2Y12 Inhibitor Ticagrelor or Clopidogrel to Halt Ischemic Events in Patients Undergoing Elective Coronary Stenting (ALPHEUS) trial, which compared ticagrelor with clopidogrel in high-risk patients who received elective PCI.

METHODS

The ALPHEUS trial divided 1809 patients into quartiles of loading time. The ALPHEUS primary outcome was used (type 4 [a or b] myocardial infarction or major myocardial injury) as well as the main secondary outcome (type 4 [a or b] myocardial infarction or any type of myocardial injury).

RESULTS

Patients in the first quartile group (Q1) presented higher rates of the primary outcome (P = 0.01). When compared with Q1, incidences of the primary outcome decreased in patients with longer loading times (adjusted odds ratio [adjOR], 0.70 [0.52.-0.95]; P = 0.02 for Q2; adjOR 0.65 [0.48-0.88]; P < 0.01 for Q3; adjOR 0.66 [0.49-0.89]; P < 0.01 for Q4). Concordant results were found for the main secondary outcome. There was no interaction with the study drug allocated by randomization (clopidogrel or ticagrelor). Bleeding complications (any bleeding ranging between 4.9% and 7.3% and only 1 major bleeding at 48 hours) and clinical ischemic events were rare and did not differ among groups.

CONCLUSIONS

In elective PCI, administration of the oral P2Y12 inhibitor at the time of PCI could be associated with more frequent periprocedural myocardial necrosis than an earlier administration. The long-term clinical consequences remain unknown.

Trajectories of P2Y12 inhibitor adherence in patients with acute coronary syndromes

PURPOSE

P2Y12 inhibitors (P2Y12i) reduce cardiac events after acute coronary syndromes (ACS). However, suboptimal P2Y12i adherence persists. We aimed to examine P2Y12i non-adherence using group-based trajectory methods and to identify adherence predictors.

METHODS

We conducted a population-based, retrospective cohort study using administrative data in Ontario, Canada of patients ≥65 years admitted for ACS between April 2014 and March 2018 with a P2Y12i dispensed within 7 days of discharge. We used group-based trajectory models to characterize longitudinal 1-year adherence patterns. Predictors associated with each adherence trajectory were identified by multinomial logistic regression.

RESULTS

We included 11 917 patients using clopidogrel and 9763 using ticagrelor, aged [mean ± SD]: 77.33 ± 8.31/73.59 ± 6.79 years; men: 56.2%/65.4%, respectively. We identified 3 longitudinal adherence trajectories, that differed by agent: 75% of clopidogrel and 68% of ticagrelor patients showed a consistently adherent trajectory, while 13%/17% were gradually, and 12%/15% were rapidly non-adherent, respectively (p < 0.001). Differing baseline characteristics in each cohort were associated with observed adherence trajectories. Concomitant atrial fibrillation and prior bleeding history were associated with non-adherence among clopidogrel users. Among ticagrelor users, women and older persons were more likely to be rapidly non-adherent, adherence declining steeply starting 1 month post-ACS.

CONCLUSIONS

We identified distinct adherence trajectories for clopidogrel and ticagrelor post-ACS, with 3 out of 4 clopidogrel patients but only 2 out of 3 ticagrelor patients in the consistently adherent trajectory. Intensive interventions targeted to the period of steep adherence decline post-ACS, particularly for women and older persons initiating ticagrelor, and patients with atrial fibrillation on clopidogrel should be considered and investigated further.

Comparison of Ticagrelor and Clopidogrel in Patients With Acute Coronary Syndrome at High Bleeding or Ischemic Risk

Current guidelines recommend individualizing the choice and duration of P2Y12 inhibitor therapy based on the trade-off between bleeding and ischemic risk. However, whether a potent P2Y12 inhibitor (ticagrelor) or a less potent one (clopidogrel) is more appropriate in patients with acute coronary syndrome (ACS) in the setting of high bleeding or ischemic risk is not clear. The study aimed to compare the clinical outcomes of clopidogrel and ticagrelor in patients with ACS at high bleeding or ischemic risk. A total of 5,713 patients with ACS were included in this retrospective study. The Cox proportional hazard regression model was adjusted by applying the inverse probability weighted approach to reduce treatment selection bias. The primary clinical outcome was all-cause death. Secondary outcomes included in-hospital death, ACS, target vessel revascularization, stent thrombosis, stroke, or clinically significant or major bleeding. The median follow-up duration was 53.6 months. After multivariable Cox model using an inverse probability weighted approach, all-cause death in the overall population and subgroups of patients at high bleeding risk, and/or at high ischemic risk were not significantly different between clopidogrel and ticagrelor. Rates for secondary outcomes were also similar between the groups. In conclusion, ticagrelor and clopidogrel are associated with comparable clinical outcomes in patients with ACS irrespective of bleeding and ischemic risk.

Effects of ticagrelor and prasugrel on coronary microcirculation in elective percutaneous coronary intervention

OBJECTIVE

To compare the effects of ticagrelor and prasugrel on absolute coronary blood flow (Q) and microvascular resistance (R) in patients with stable coronary artery disease (CAD) treated with elective percutaneous coronary intervention (PCI) (NCT05643586). Besides being at least as effective as prasugrel in inhibiting platelet aggregation, ticagrelor has been shown to have additional properties potentially affecting coronary microcirculation.

METHODS

We randomly assigned 50 patients to ticagrelor (180 mg) or prasugrel (60 mg) at least 12 hours before intervention. Continuous thermodilution was used to measure Q and R before and after PCI. Platelet reactivity was measured before PCI. Troponin I was measured before, 8 and 24 hours after PCI.

RESULTS

At baseline, fractional flow reserve, Q and R were similar in two study groups. Patients in the ticagrelor group showed higher post-PCI Q (242±49 vs 205±53 mL/min, p=0.015) and lower R values (311 (263, 366) vs 362 (319, 382) mm Hg/L/min, p=0.032). Platelet reactivity showed a negative correlation with periprocedural variation of Q values (r=-0.582, p<0.001) and a positive correlation with periprocedural variation of R values (r=0.645, p<0.001). The periprocedural increase in high-sensitivity troponin I was significantly lower in the ticagrelor compared with the prasugrel group (5 (4, 9) ng/mL vs 14 (10, 24) ng/mL, p<0.001).

CONCLUSIONS

In patients with stable CAD undergoing PCI, pretreatment with a loading dose of ticagrelor compared with prasugrel improves post-procedural coronary flow and microvascular function and seems to reduce the related myocardial injury.

Off-Target Effects of P2Y12 Receptor Inhibitors: Focus on Early Myocardial Fibrosis Modulation

Several studies have demonstrated that, beyond their antithrombotic effects, P2Y12 receptor inhibitors may provide additional off-target effects through different mechanisms. These effects range from the preservation of endothelial barrier function to the modulation of inflammation or stabilization of atherosclerotic plaques, with an impact on different cell types, including endothelial and immune cells. Many P2Y12 inhibitors have been developed, from ticlopidine, the first thienopyridine, to the more potent non-thienopyridine derivatives such as ticagrelor which may promote cardioprotective effects following myocardial infarction (MI) by inhibiting adenosine reuptake through sodium-independent equilibrative nucleoside transporter 1 (ENT1). Adenosine may affect different molecular pathways involved in cardiac fibrosis, such as the Wnt (wingless-type)/beta (β)-catenin signaling. An early pro-fibrotic response of the epicardium and activation of cardiac fibroblasts with the involvement of Wnt1 (wingless-type family member 1)/β-catenin, are critically required for preserving cardiac function after acute ischemic cardiac injury. This review discusses molecular signaling pathways involved in cardiac fibrosis post MI, focusing on the Wnt/β-catenin pathway, and the off-target effect of P2Y12 receptor inhibition. A potential role of ticagrelor was speculated in the early modulation of cardiac fibrosis, thanks to its off-target effect.

P2Y12 receptor mediates apoptosis and demyelination to affect functional recovery in mice with spinal cord injury

Among diseases of the central nervous system (CNS), spinal cord injury (SCI) has a high fatality rate. It has been proven that P2Y G protein-coupled purinergic receptors have a neuroprotective role in apoptosis and regeneration inside the damaged spinal cord. The P2Y12 receptor (P2Y12R) has recently been linked to peripheral neuropathy and stroke. However, the role of P2Y12R after SCI remains unclear. Our study randomly divided C57BL/6J female mice into 3 groups: Sham+DMSO, SCI+DMSO, and SCI+MRS2395. MRS2395 as a P2Y12R inhibitor was intraperitoneally injected at a dose of 1.5 mg/kg once daily for 7 days. We showed that the P2Y12R was markedly activated after injury, and it was double labeled with the microglial and neuron. Behavioral tests were employed to assess motor function recovery. By using immunofluorescence staining, the NeuN expression level was detected. The morphology of neurons was observed by hematoxylin-eosin and Nissl staining. P2Y12R, Bax, GFAP, PCNA and calbindin expression levels were detected using Western blot. Meanwhile, mitochondria and myelin sheath were observed by transmission electron microscopy (TEM). Our findings demonstrated that MRS2395 significantly enhanced motor function induced by SCI and that was used to alleviate apoptosis and astrocyte scarring. NeuN positive cells in the SCI group were lower than in the therapy group, although Bax, GFAP, PCNA and calbindin expression levels were considerably higher. Moreover, following MRS2395 therapy, the histological damage was reversed. A notable improvement in myelin sheath and mitochondrial morphology was seen in the therapy group. Together, our findings indicate that activation of P2Y12R in damaged spinal cord may be a critical event and suggest that inhibition of P2Y12R might be a feasible therapeutic strategy for treating SCI.

Discordance in tests used to detect inhibition of the P2Y12 receptor in patients undergoing interventional neuroradiology procedures

BACKGROUND

Clopidogrel is an inhibitor of the P2Y12 platelet receptor but testing to demonstrate a drug effect is controversial since there are often discordant results between different tests methods.

METHODS

Samples from patients taking clopidogrel prior to intracranial flow-diversion procedures were tested using light transmission aggregometry (LTA), whole blood impedance aggregometry (WBIA) and the VerifyNow device (VND). Samples were classified as concordant if all test results were either responsive (inhibition) or resistant. Discordant results were separated using the VND into those with a responsive versus a resistant test result.

RESULTS

Samples from 96 patients were studied. Concordance for all three tests was seen in 53/96 (55%) of samples, of which 41 (43%) were responsive and 12 (12%) were resistant. Discordance was observed in 43 samples (45%), 37 (28%) of which were caused by responsive VND and either a resistant WBIA or LTA and 6 (7%) of which were caused by a resistant VND but a responsive test result using either WBIA or LTA. These two discordant groups differed in both platelet count and hematocrit, but no such difference was present between the two concordant groups.

CONCLUSION

Discordance in P2Y12 inhibition testing may be partly explained by sample platelet count and hematocrit.

Utilization of P2Y12 Inhibitors in Older Adults With ST-Elevation Myocardial Infarction and Frailty

Choosing optimal P2Y12 inhibitor in frail older adults is challenging because they are at increased risk of both ischemic and bleeding events. We conducted a retrospective cohort study of Medicare Advantage Plan beneficiaries who were prescribed clopidogrel, prasugrel, or ticagrelor after percutaneous coronary intervention-treated ST-elevation myocardial infarction from January 1, 2010 to December 31, 2020. Frailty was defined using claims-based frailty index ≥0.25. We conducted multivariable logistic regression to identify factors associated with using potent P2Y12 inhibitors and multivariable-adjusted competing risk analyses to compare the rate of discontinuation of potent P2Y12 inhibitors in frail versus non-frail patients. There were 11,239 patients (mean age 74 years, 39% women). The prevalence of cardiovascular and geriatric co-morbidities was as follows: 32% chronic kidney disease, 28% heart failure, 10% previous myocardial infarction, 6% dementia, 20% anemia, and 12% frailty. The proportion of patients receiving clopidogrel decreased from 78.3% in 2010 to 2013 to 42.1% in 2018 to 2020, with a concurrent increase in those receiving potent P2Y12 inhibitors (mostly ticagrelor) from 21.7% to 57.9%. Frailty was independently associated with reduced odds of initiation (odds ratio 0.78, 95% confidence interval 0.67 to 0.90) but not with discontinuation of potent P2Y12 inhibitors (subdistribution hazard ratio 1.09, 95% confidence interval 0.98 to 1.22). In conclusion, frail older adults are less likely to receive potent P2Y12 inhibitors after percutaneous coronary intervention-treated ST-elevation myocardial infarction, but they are as likely as non-frail patients to continue with the prescribed P2Y12 inhibitor.

Ticagrelor Versus Prasugrel in Patients With Acute Coronary Syndrome: A Systematic Review and Meta-Analysis

Limited data comparing prasugrel and ticagrelor in acute coronary syndrome are available. Online databases, including MEDLINE and Cochrane Central, were queried to compare these drugs. The primary outcomes of this meta-analysis are myocardial infarction (MI), all-cause mortality, cardiovascular mortality, noncardiovascular mortality, stent thrombosis, and stroke. The secondary outcome is major bleeding. A total of 9 studies, including 94,590 patients (prasugrel group = 32,759; ticagrelor group = 61,831), were included in this meta-analysis. The overall mean age was 62.73 years, whereas the mean age for the ticagrelor and prasugrel groups was 63.80 and 61.65 years, respectively. Prasugrel is equally effective as compared with ticagrelor in preventing MI. There was no difference between the 2 groups regarding all-cause mortality, stent thrombosis, stroke, or major bleeding. In patients with acute coronary syndrome, prasugrel is equally effective when compared with ticagrelor in preventing MI.

Age- and Sex-Specific Disparities in Outcomes After Ticagrelor Versus Clopidogrel in East Asian Patients

It is unknown whether there are age- and gender-related differences in the safety and efficacy of potent P2Y12 inhibitors in East Asian populations with a different bleeding or ischemic propensity. Using data from the TICAKOREA (Ticagrelor Versus Clopidogrel in Asian/Korean Patients with ACS Intended for Invasive Management) trial comparing ticagrelor versus clopidogrel for 800 Korean patients with acute coronary syndrome, the safety and efficacy outcomes were compared according to age (<75 vs ≥75 years) and gender (men vs women). The primary bleeding end point was clinically significant bleeding, and the primary ischemic end point was a major adverse cardiovascular event (MACE) at 12 months. The incidences of clinically significant bleeding were significantly higher after ticagrelor than after clopidogrel in patients aged <75 years (adjusted hazard ratio [HR] 2.56, 95% confidence interval [CI] 1.40 to 4.67) but not in patients aged ≥75 years (adjusted HR 1.1, 95% CI 0.40 to 3.38). The incidences of MACEs were significantly higher after ticagrelor than after clopidogrel in patients aged ≥75 years (adjusted HR 6.14, 95% CI 1.40 to 26.90) but not in patients aged <75 years (adjusted HR 0.93, 95% CI 0.50 to 1.73). The incidences of clinically significant bleeding were significantly higher after ticagrelor than after clopidogrel in men (adjusted HR 2.69, 95% CI 1.38 to 5.24) but not in women (adjusted HR 1.49, 95% CI 0.64 to 3.46). The adjusted risks of MACEs after ticagrelor or clopidogrel were not significantly different between men and women. In conclusion, there were substantial age- and gender-related differences in bleeding and ischemic outcomes after ticagrelor or clopidogrel in Korean patients with acute coronary syndrome. Clinical Trial Registration: URL: https://www.clinicaltrials.gov Unique identifier: NCT02094963.

In CAD, P2Y12 inhibitor vs. aspirin monotherapy reduces a composite CV outcome without increasing major bleeding

SOURCE CITATION

Gragnano F, Cao D, Pirondini L, et al; PANTHER Collaboration. P2Y12 inhibitor or aspirin monotherapy for secondary prevention of coronary events. J Am Coll Cardiol. 2023;82:89-105. 37407118.

Aspirin Dosing for Secondary Prevention of Atherosclerotic Cardiovascular Disease in Patients Treated With P2Y12 Inhibitors

Background The ADAPTABLE (Aspirin Dosing: A Patient-Centric Trial Assessing Benefits and Long-Term Effectiveness) was a large, pragmatic, randomized controlled trial that found no difference between high- versus low-dose aspirin for secondary prevention of atherosclerotic cardiovascular disease. Whether concomitant P2Y12 inhibitor therapy modifies the effect of aspirin dose on clinical events remains unclear. Methods and Results Participants in ADAPTABLE were stratified according to baseline use of clopidogrel or prasugrel (P2Y12 group). The primary effectiveness end point was a composite of death, myocardial infarction, or stroke; and the primary safety end point was major bleeding requiring blood transfusions. We used multivariable Cox regression to compare the relative effectiveness and safety of aspirin dose within P2Y12 and non-P2Y12 groups. Of 13 815 (91.6%) participants with available data, 3051 (22.1%) were receiving clopidogrel (2849 [93.4%]) or prasugrel (203 [6.7%]) at baseline. P2Y12 inhibitor use was associated with higher risk of the primary effectiveness end point (10.86% versus 6.31%; adjusted hazard ratio [HR], 1.40 [95% CI, 1.22-1.62]) but was not associated with bleeding (0.95% versus 0.53%; adjusted HR, 1.42 [95% CI, 0.91-2.22]). We found no interaction in the relative effectiveness and safety of high- versus low-dose aspirin by P2Y12 inhibitor use. Overall, dose switching or discontinuation was more common in the high-dose compared with low-dose aspirin group, but the pattern was not modified by P2Y12 inhibitor use. Conclusions In this prespecified analysis of ADAPTABLE, we found that the relative effectiveness and safety of high- versus low-dose aspirin was not modified by baseline P2Y12 inhibitor use. Registration https://www.clinical.trials.gov. Unique identifier: NCT02697916.

Outcomes with P2Y12 inhibitor monotherapy after PCI according to bleeding risk: A Bayesian meta-analysis

BACKGROUND

P2Y12 inhibitor monotherapy is a promising novel strategy to reduce bleeding complications compared to dual antiplatelet therapy (DAPT) in patients undergoing percutaneous coronary intervention (PCI). In order to personalise treatment with DAPT based on patients' bleeding risk, we compared outcomes after PCI between P2Y12 inhibitor monotherapy and DAPT according to bleeding risk.

METHODS

A search for randomized clinical trials (RCTs) comparing P2Y12 inhibitor monotherapy after a short period of DAPT to standard DAPT after PCI was performed. Outcome differences between treatment groups regarding major bleedings, major adverse cardiac and cerebral events (MACCE) and net adverse clinical events (NACE) were assessed with hazard ratios (HRs) and corresponding credible intervals (CrI) according a Bayesian random effects model in patients with and without high bleeding risk (HBR).

RESULTS

Five RCTs including 30,084 patients were selected. P2Y12 inhibitor monotherapy compared to DAPT reduced major bleedings in the total population (HR: 0.65, 95 % CrI: 0.44 to 0.92). The HRs of the HBR and non-HBR subgroups showed a similar reduction of bleedings for monotherapy (HBR: HR 0.66, 95 % CrI: 0.25 to 1.74; non-HBR: HR 0.63, 95 % CrI: 0.36 to 1.09). No notable differences between treatments on MACCE and NACE were observed in either sub-group or in the total population.

CONCLUSIONS

Regardless of bleeding risk, P2Y12 inhibitor monotherapy is the favourable choice after PCI regarding major bleedings and does not increase ischemic events compared to DAPT. This suggests that bleeding risk is not decisive when considering P2Y12 inhibitor monotherapy.

Platelet Inhibition with Ticagrelor 60 mg Versus 90 mg Twice Daily in Elderly Patients with Acute Coronary Syndrome: Rationale and Design of the PLINY THE ELDER Trial

BACKGROUND

Elderly status is steadily increasing among patients with acute coronary syndrome (ACS). Dual antiplatelet therapy (DAPT) with aspirin and a potent P2Y12 receptor inhibitor is the cornerstone of treatment to prevent recurrent thrombotic complications in patients with ACS. However, DAPT in older patients is challenged by a concurrent heightened risk of ischemia and bleeding. The aim of this study is to evaluate the pharmacodynamic and pharmacokinetic profile of a lower dose of ticagrelor (60 mg twice daily) among elderly patients during the early phase of ACS.

STUDY DESIGN

PLINY THE ELDER (PLatelet INhibition with two different doses of potent P2y12 inhibitors in THE ELDERly population) (NCT04739384) is a prospective, randomized, open-label, crossover trial to evaluate the non-inferiority of a lower dose of ticagrelor (60 mg twice daily) compared with a standard dose (90 mg twice daily) among elderly patients with ACS undergoing percutaneous coronary intervention (PCI). A total of 50 patients, aged 75 years or more, with indication to potent P2Y12 receptor inhibitors will be randomized within 3 days from PCI for the index ACS. Patients with indication to oral anticoagulant therapy, treatment with glycoprotein IIb/IIIa inhibitors, or active bleeding will be excluded. The primary endpoint is platelet reactivity determined by P2Y12 reaction units (PRU) (VerifyNow, Accumetrics, San Diego, CA, USA) after treatment with ticagrelor 60 or 90 mg twice daily for 14 days. Secondary endpoints will include other pharmacodynamic tests of ADP-induced aggregation (light transmittance aggregometry and multiple electrode aggregometry) and determination of pharmacokinetic profile (plasma levels of ticagrelor and its metabolite AR-C124910XX) by high performance liquid chromatography-tandem mass spectrometry.

CONCLUSIONS

The PLINY THE ELDER trial will determine whether a lower dose of ticagrelor confers non-inferior platelet inhibition compared with the standard dose in the early phase of ACS among elderly patients undergoing PCI, informing future clinical investigation.

Pretreatment with a P2Y12 receptor inhibitor and delay to coronary artery bypass surgery in patients with non-ST segment elevation acute coronary syndrome

BACKGROUND

2020 ESC guidelines for non-ST elevation acute coronary syndromes (NSTE-ACS) recommend against the pretreatment with P2Y12 receptor inhibitors (P2Y12i) in patients undergoing early invasive management (<24 h). The rationale is, in part, to prevent bleeding complications and the delay of coronary artery bypass graft surgery (CABG) in patients with suitable coronary anatomy. This study aimed to analyze the theoretical impact of pretreatment with a P2Y12i on delay to CABG surgery in a real-world population with NSTE-ACS.

METHODS

Single-center retrospective cohort of consecutive patients with NSTE-ACS undergoing invasive evaluation in 2019. Those with previous CABG or nonobstructive coronary disease were excluded.

RESULTS

The total cohort included 262 patients (mean age 68±12 years, 69% male, 15% with unstable angina and mean GRACE score 134±35). Median time from FMC to angiography was 2 (1-4) days. Overall, 168 (64%) patients underwent percutaneous coronary intervention, 47 (18%) were proposed for CABG and the remainder received conservative management. All patients considered for CABG received pretreatment with P2Y12i (clopidogrel or ticagrelor). The median time from angiography to CABG was 12 (7-15) days. Six patients experienced recurrent angina (13%) and 2 (4%) died before surgery due to refractory ventricular fibrillation. Those who underwent CABG under P2Y12i effect were more likely to receive blood and platelets transfusions (64.7% vs. 28.6%, P=0.017 and 82.4% vs. 21.4%, P<0.001, respectively), although there were no differences regarding major bleeding.

CONCLUSIONS

Pretreatment with P2Y12i was a potential but not the sole driver of CABG delay in our cohort. Adopting the new recommendations of withholding pretreatment might decrease this delay, but other factors must be considered.

P2Y12 inhibitor monotherapy after complex percutaneous coronary intervention: a systematic review and meta-analysis of randomized clinical trials

It remains unknown whether the recent trend of short dual antiplatelet therapy (DAPT) followed by P2Y12 inhibitor monotherapy can simply be applied to patients undergoing complex percutaneous coronary intervention (PCI). We performed a systematic review and meta-analysis to evaluate P2Y12 inhibitor monotherapy vs. conventional DAPT in patients undergoing complex PCI and non-complex PCI (PROSPERO: CRD42022335723). Primary endpoint was the 1-year Net Adverse Clinical Event (NACE). Among 5,323 screened studies, six randomized trials fulfilled the eligibility criteria. A total of 10,588 complex PCI patients (5,269 vs. 5,319 patients) and 25,618 non-complex PCI patients (12,820 vs 12,798 patients) were randomly assigned to P2Y12 inhibitor monotherapy vs. conventional DAPT. In complex PCI patients, P2Y12 inhibitor monotherapy was associated with a lower risk of NACE than conventional DAPT [Odds ratio (OR) 0.76, 95% confidence interval (CI) 0.63-0.91, P = 0.003], whereas in non-complex PCI patients, P2Y12 inhibitor monotherapy was associated with a trend toward lowering the risk of NACE (OR 0.86, 95% CI 0.72-1.02, P = 0.09). This meta-analysis across randomized trials demonstrated that a strategy of short DAPT followed by P2Y12 inhibitor monotherapy reduces the risk of 1-year NACE in patients undergoing complex PCI.

Implementation of CYP2C19 genotyping and clinical outcomes following percutaneous coronary intervention in East Asian patients treated with oral P2Y12 inhibitors

BACKGROUND

The CYP2C19 loss-of-function variants have significant impact on response to clopidogrel. The efficacy and safety of tailored antiplatelet therapy under the guidance of CYP2C19 genetic polymorphisms remains elusive for patients undergoing percutaneous coronary intervention (PCI).

OBJECTIVES

The aims of the present study were to investigate the impact of clinical implementation of CYP2C19 genotyping on the selection of oral P2Y12 inhibitor therapy following PCI, and to estimate the risk of adverse outcomes for patients with different genotype status treated with alternative or traditional P2Y12 inhibitor.

METHODS

Data from a single-center registry enrolling 41,090 consecutive PCI patients treated with dual antiplatelet therapy after PCI were analyzed. Risk of major adverse cardiovascular events (MACEs) and bleeding events within 12 months after PCI were compared across CYP2C19 genotype and antiplatelet therapy groups using Cox proportional hazards models.

RESULTS

CYP2C19 genotyping was successfully achieved for 9081 patients, of whom baseline characteristics significantly differed from non-genotyped patients. A higher proportion of genotyped patients were prescribed ticagrelor compared with non-genotyped patients (27.0 % vs. 15.5 %, P < 0.001). CYP2C19 metabolic status was an independent predictor for use of ticagrelor (P < 0.001). Ticagrelor was significantly associated with a lower risk of MACEs in poor metabolizers (adjusted hazard ratio 0.62, 95 % confidence interval 0.42 to 0.92, P = 0.017), but not in intermediate metabolizers or normal metabolizers. The interaction was not statistically significant (P for interaction = 0.252).

CONCLUSIONS

Genotype information on CYP2C19 metabolic status was associated with an increase in the use of potent antiplatelet therapy in PCI patients. Patients prescribed with clopidogrel has a higher risk of MACEs among poor metabolizers, which suggested the potential application of genotype-guided P2Y12 inhibitor selection for improving clinical outcomes.

Dual Antiplatelet Therapy with 3rd Generation P2Y12 Inhibitors in STEMI Patients: Impact of Body Mass Index on Loading Dose-Response

PURPOSE

This study aims to assess the association between body mass index (BMI) and platelet reactivity in STEMI patients treated with oral 3rd generation P2Y12 inhibitors.

METHODS

Overall, 429 STEMI patients were enrolled in this study. Patients were divided into two groups according to BMI (BMI < 25 vs ≥ 25 kg/m2). A propensity score matching (1:1) was performed to balance potential confounders in patient baseline characteristics. Platelet reactivity was assessed by VerifyNow at baseline and after 3rd generation P2Y12 inhibitor (ticagrelor or prasugrel) loading dose (LD). Blood samples were obtained at baseline (T0), 1 h (T1), 2 h (T2), 4-6 h (T3), and 8-12 h (T4) after the LD. High on-treatment platelet reactivity (HTPR) was defined as a platelet reactivity unit value ≥ 208 units.

RESULTS

After propensity score matching, patients with BMI ≥ 25 had similar values of baseline platelet reactivity, while they had higher level of platelet reactivity at 1 and 2 h after the LD and higher rate of HRPT. Furthermore, multivariate analysis demonstrated that BMI ≥ 25 was an independent predictor of HTPR at 2 h (OR 2.01, p = .009). Conversely, starting from 4 h after the LD, platelet reactivity values and HRPT rates were comparable among the two study groups.

CONCLUSIONS

A BMI ≥ 25 kg/m2 is associated with delayed pharmacodynamic response to oral 3rd generation P2Y12 inhibitor LD, and it is a strong predictor of HTPR in STEMI patients treated by dual antiplatelet therapy with ticagrelor or prasugrel.

Ticagrelor or prasugrel versus clopidogrel in patients undergoing percutaneous coronary intervention for chronic coronary syndromes

BACKGROUND

Potent P2Y12 inhibitors such as ticagrelor and prasugrel are superior to clopidogrel in acute coronary syndrome (ACS) patients treated with percutaneous coronary intervention (PCI). Whether this benefit extends to a patient population with chronic coronary syndromes (CCS) is unclear.

AIMS

We sought to compare the safety and efficacy of prasugrel and ticagrelor versus clopidogrel in patients undergoing PCI for CCS.

METHODS

Consecutive patients undergoing PCI for CCS at a tertiary centre between 2014 and 2019 who were discharged on prasugrel or ticagrelor were compared with those on clopidogrel. The primary endpoint was the composite of death and myocardial infarction (MI), with secondary outcomes including rates of bleeding, stroke, and target vessel revascularisation at 1 year.

RESULTS

Overall, 11,508 patients were included in the study (ticagrelor/prasugrel n=2,860 [24.9%], clopidogrel n=8,648 [75.1%]) with an increasing frequency of potent P2Y12 inhibitor use over the study period (ptrend<0.001). Clopidogrel was used more frequently in patients with multimorbid risk factors, whereas anatomical or procedural complexity was associated with ticagrelor/prasugrel use (left main PCI, bifurcation PCI, number of lesions, rotational atherectomy). No difference in the incidence of death or MI was noted across the groups (ticagrelor/prasugrel vs clopidogrel: 2.7% vs 3.1%, adjusted hazard ratio [adjHR] 0.86, 95% confidence interval [CI]: 0.62-1.17; p=0.33) or secondary outcomes including bleeding (adjHR 0.75, 95% CI: 0.46-1.21; p=0.23) on propensity score stratification analysis. Additionally, no difference in the primary outcome was observed across subgroups, including those undergoing complex PCI.

CONCLUSIONS

Ticagrelor and prasugrel are increasingly used in patients with CCS undergoing PCI with similar 1-year efficacy and safety when compared to clopidogrel. Whether use of these agents can be beneficial in patients undergoing PCI for CCS with a high thrombotic and low bleeding risk warrants further study.

Feasibility of Community Pharmacist-Initiated and Point-of-Care CYP2C19 Genotype-Guided De-Escalation of Oral P2Y12 Inhibitors

Tailoring antiplatelet therapy based on CYP2C19 pharmacogenetic (PGx) testing can improve cardiovascular outcomes and potentially reduce healthcare costs in patients on a P2Y12-inhibitor regime with prasugrel or ticagrelor. However, ubiquitous adoption—particularly in an outpatient setting—remains limited. We conducted a proof-of-concept study to evaluate the feasibility of CYP2C19-guided de-escalation of prasugrel/ticagrelor to clopidogrel through point-of-care (POC) PGx testing in the community pharmacy. Multiple feasibility outcomes were assessed. Overall, 144 patients underwent CYP2C19 PGx testing in 27 community pharmacies. Successful test results were obtained in 142 patients (98.6%). De-escalation to clopidogrel occurred in 19 patients (20%) out of 95 (67%) eligible for therapy de-escalation, which was mainly due to PGx testing not being included in cardiology guidelines. Out of the 119 patients (84%) and 14 pharmacists (100%) surveyed, 109 patients (92%) found the community pharmacy a suitable location for PGx testing, and the majority of pharmacists (86%) thought it has added value. Net costs due to PGx testing were estimated at €43 per patient, which could be reduced by earlier testing and could turn into savings if de-escalation would double to 40%. Although the observed de-escalation rate was low, POC CYP2C19-guided de-escalation to clopidogrel appears feasible in a community pharmacy setting.

Comparative Effectiveness of Ticagrelor, Prasugrel, and Clopidogrel for Secondary Prophylaxis in Acute Coronary Syndrome: A Propensity Score-Matched Cohort Study

Comparative effectiveness evaluation of newer P2Y12 inhibitors (prasugrel and ticagrelor) compared with clopidogrel after acute coronary syndrome (ACS) is limited in real-world US populations. The objective of this study was to evaluate cardiovascular events based on ticagrelor, prasugrel, and clopidogrel use in a real-world patient setting. This retrospective cohort study used the IBM MarketScan database (January 1, 2013, to December 31, 2018) to create three propensity score-matched pairs: ticagrelor vs. clopidogrel (N = 21,719), prasugrel vs. clopidogrel (N = 11,513), and prasugrel vs. ticagrelor (N = 11,065). The primary outcome was a composite of myocardial ischemia, unstable angina, stroke, and heart failure hospitalization. These groups were compared in a time-to-event analysis for the primary outcome at 30, 90, and 180 days following P2Y12 inhibitors initiation after percutaneous coronary intervention. Compared with clopidogrel, ticagrelor use suggested a 10% reduction in the primary outcome at 90 days (hazard ratio (HR): 0.90, 95% confidence interval (CI): 0.82-0.99). There were no differences for all other matched pairs or follow-up combinations. In the subgroup analysis of females, the results suggested a risk reduction of 27% for prasugrel at 30 days (HR: 0.73, 95% CI: 0.53-1.00) and 17% for ticagrelor at 90 days (HR: 0.83, 95% CI: 0.70-0.98) when compared with clopidogrel. Among patients treated with bare-metal stents, the results suggested that prasugrel vs. ticagrelor was associated with a 55% and 33% reduced risk for the primary outcome at 30 days and 180 days, respectively. With limited evidence in the United States comparing these drugs, this study helps inform clinicians when choosing P2Y12 inhibitors after ACS.

Pre-hospital treatment with crushed versus integral tablets of prasugrel in patients presenting with ST-Segment Elevation Myocardial Infarction-1-year follow-up results of the COMPARE CRUSH trial

The present research letter reports the 1-year clinical outcomes of the randomized COMPARE CRUSH trial, which allocated STEMI patients at first medical contact in the ambulance to receive either crushed or integral tablets of prasugrel loading dose. This trial aimed to investigate whether early enhanced antiplatelet effect constituted by the crushed potent oral P2Y₁₂ inhibitor prasugrel could lead to improved early myocardial reperfusion and clinical outcomes.

Rationale and design of switch Swedeheart: A registry-based, stepped-wedge, cluster-randomized, open-label multicenter trial to compare prasugrel and ticagrelor for treatment of patients with acute coronary syndrome

BACKGROUND

European treatment guidelines recommend prasugrel over ticagrelor for treating patients with non-ST-elevation acute coronary syndrome (ACS), prompting several Swedish administrative regions to transition from ticagrelor to prasugrel as the preferred treatment for patients with ACS. We aim to systematically evaluate this transition to determine the relative efficacy of prasugrel versus ticagrelor in a real-world cohort of patients with ACS.

STUDY DESIGN AND OBJECTIVES

The SWITCH SWEDEHEART trial is a prospective, multicenter, open-label, cross-sectional, stepped-wedge cluster-randomized clinical trial, in which administrative regions in Sweden will constitute the clusters. At the start of the study, all clusters will use ticagrelor as the P2Y12 inhibitor drug of choice for ACS. The order in which the clusters will implement the transition from ticagrelor to prasugrel will be randomly assigned. Every 9 months, 1 cluster will switch from ticagrelor to prasugrel as the P2Y12 inhibitor of choice for patients with ACS. The primary endpoint is the composite 1-year rate of the death, stroke, or myocardial infarction.

CONCLUSIONS

The SWITCH SWEDEHEART study will provide an extensive randomized comparison between ticagrelor and prasugrel. Novel therapies are frequently costly and supported by evidence from few or small studies, and systematic evaluation after the introduction is rare. This study will establish an important standard for introducing and evaluating the effects of health care changes within our societies.

Protease-activated receptor-mediated platelet aggregation in patients with type 2 diabetes on potent P2Y12 inhibitors

BACKGROUND

Antiplatelet therapy is a cornerstone in the secondary prevention of ischemic events following percutaneous coronary intervention (PCI). The new P2Y₁₂ receptor inhibitors prasugrel and ticagrelor have been shown to improve patients' outcomes. Whether or not these drugs have equal efficacy in individuals with or without diabetes is disputed. Furthermore, platelets can be activated by thrombin, which is, at least in part, independent of P2Y₁₂ -mediated platelet activation. Protease-activated receptor (PAR)-1 and -4 are thrombin receptors on human platelets. We sought to compare the in vitro efficacy of prasugrel (n = 121) and ticagrelor (n = 99) to inhibit PAR-mediated platelet aggregation in individuals with type 2 diabetes (prasugrel n = 26, ticagrelor n = 29).

MATERIALS AND METHODS

We compared P2Y₁₂ -, PAR-1- and PAR-4-mediated platelet aggregation as assessed by multiple electrode platelet aggregometry between prasugrel- and ticagrelor-treated patients without and with type 2 diabetes who underwent acute PCI.

RESULTS

Overall, there were no differences of P2Y₁₂ -, PAR-1- and PAR-4-mediated platelet aggregation between prasugrel- and ticagrelor-treated patients. However, both drugs inhibited P2Y₁₂ -mediated platelet aggregation stronger, and thereby to a similar extent in patients with type 2 diabetes than in those without diabetes. There was no correlation between either P2Y₁₂ -, or PAR-1- or PAR-4-mediated platelet aggregation and levels of HbA1c or the body mass index (BMI). However, we observed patients with high residual platelet reactivity in response to PAR-1 and PAR-4 stimulation in all cohorts.

CONCLUSION

Prasugrel and ticagrelor inhibit P2Y₁₂ - and PAR-mediated platelet aggregation in individuals with diabetes to a similar extent, irrespective of HbA_1c levels and BMI.

Newer P2Y12 Inhibitors vs Clopidogrel in Acute Myocardial Infarction With Cardiac Arrest or Cardiogenic Shock: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the outcomes, safety, and efficacy of dual antiplatelet therapy (DAPT) with newer P2Y₁₂ inhibitors compared with clopidogrel in patients with acute myocardial infarction (AMI) complicated by cardiac arrest (CA) or cardiogenic shock (CS).

PATIENTS AND METHODS

MEDLINE, EMBASE, and the Cochrane Library were queried systematically from inception to January 2021 for comparative studies of adults (≥18 years) with AMI-CA/CS receiving DAPT with newer P2Y₁₂ inhibitors as opposed to clopidogrel. We compared outcomes (30-day or in-hospital and 1-year all-cause mortality, major bleeding, and definite stent thrombosis) of newer P2Y₁₂ inhibitors and clopidogrel in patients with AMI-CA/CS.

RESULTS

Eight studies (1 randomized trial and 7 cohort studies) comprising 1100 patients (695 [63.2%] receiving clopidogrel and 405 [36.8%] receiving ticagrelor or prasugrel) were included. The population was mostly male (68.5%-86.7%). Risk of bias was low for these studies, with between-study heterogeneity and subgroup differences not statistically significant. Compared with the clopidogrel cohort, the newer P2Y₁₂ cohort had lower rates of early mortality (odds ratio [OR], 0.60; 95% CI, 0.45 to 0.81; P=.001) (7 studies) and 1-year mortality (OR, 0.51; 95% CI, 0.36 to 0.71; P<.001) (3 studies). We did not find a significant difference in major bleeding (OR, 1.21; 95% CI, 0.71 to 2.06; P=.48) (6 studies) or definite stent thrombosis (OR, 2.01; 95% CI, 0.63 to 6.45; P=.24) (7 studies).

CONCLUSION

In patients with AMI-CA/CS receiving DAPT, compared with clopidogrel, newer P2Y₁₂ inhibitors were associated with lower rates of early and 1-year mortality. Data on major bleeding and stent thrombosis were inconclusive.

A Review of the Role of the Antiplatelet Drug Ticagrelor in the Management of Acute Coronary Syndrome, Acute Thrombotic Disease, and Other Diseases

P2Y12 inhibitors, including aspirin, are key components of dual-antiplatelet therapy (DAPT), which is the optimal therapeutic strategy for preventing arterial thrombosis in patients with acute coronary syndromes (ACS) who underwent stent implantation. Ticagrelor is a cyclopentyl-triazole pyrimidine antiplatelet drug that was the first reversible oral P2Y12 receptor antagonist. Compared with clopidogrel, ticagrelor exerts a faster onset and offset of function by reversible and selective inhibition of platelet aggregation in ACS patients, including those with coronary artery blood revascularization. Despite improvement in stent materials, stent thrombosis (ST) due to high on-treatment platelet reactivity (HPR) to clopidogrel continues to occur. In addition to antiplatelet aggregation, ticagrelor displays pleiotropic cardioprotective effects, including improving coronary blood flow, reducing myocardial necrosis after an ischemic event, and anti-inflammatory effects. The benefits of ticagrelor over clopidogrel were consistent in the PLATO results, with lower incidence of the primary endpoint. Also, in 2020, the findings from the phase 3 THALES trial (NCT03354429) showed that aspirin combined with 90 mg of ticagrelor significantly reduced the rates of stroke and death compared with aspirin alone in patients with AIS or TIA. Here, we review recent research on the superiority of ticagrelor over clopidogrel, discuss the pharmacological mechanism, and present future perspectives. This review aims to present the roles of ticagrelor in the management of acute coronary syndrome, acute thrombotic disease, and other diseases.

Do P2Y12 receptor inhibitors prescribed poststroke modify the risk of cognitive disorder or dementia? Protocol for a target trial using multiple national Swedish registries

INTRODUCTION

The target of a class of antiplatelet medicines, P2Y12R inhibitors, exists both on platelets and on brain immune cells (microglia). This protocol aims to describe a causal (based on a counterfactual model) approach for analysing whether P2Y12R inhibitors prescribed for secondary prevention poststroke may increase the risk of cognitive disorder or dementia via their actions on microglia, using real-world evidence.

METHODS AND ANALYSIS

This will be a cohort study nested within the Swedish National Health and Medical Registers, including all people with incident stroke from 2006 to 2016. We developed directed acyclic graphs to operationalise the causal research question considering potential time-independent and time-dependent confounding, using input from several experts. We developed a study protocol following the components of the target trial approach described by Hernan et al and describe the data structure that would be required in order to make a causal inference. We also describe the statistical approach required to derive the causal estimand associated with this important clinical question; that is, a time-to-event analysis for the development of cognitive disorder or dementia at 1, 2 and 5-year follow-up, based on approaches for competing events to account for the risk of all-cause mortality. Causal effect estimates and the precision in these estimates will be quantified.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Committee of the University of Gothenburg and Confidentiality Clearance at Statistics Sweden with Dnr 937-18, and an approved addendum with Dnr 2019-0157. The analysis and interpretation of the results will be heavily reliant on the structure, quality and potential for bias of the databases used. When we implement the protocol, we will consider and document any biases specific to the dataset and conduct appropriate sensitivity analyses. Findings will be disseminated to local stakeholders via conferences, and published in appropriate scientific journals.

De-escalation from Prasugrel or Ticagrelor to Clopidogrel in Patients with Acute Coronary Syndrome Managed with Percutaneous Coronary Intervention: An Updated Meta-analysis of Randomized Clinical Trials

INTRODUCTION

We aimed to evaluate the clinical benefits of a de-escalation strategy from prasugrel or ticagrelor to clopidogrel versus continuation of prasugrel or ticagrelor along with aspirin in both strategies for patients presenting with acute coronary syndrome (ACS) and treated with percutaneous coronary intervention (PCI), and to analyze the effect of the recently published randomized clinical trial (RCT) by Park et al., which included the largest sample size ever and the largest switched number of patients, on current guidelines and practices.

DATA SOURCES

The PubMed, EMBASE, Scopus, Web of Science, Cochrane Central, and Google Scholar databases were searched systematically from inception to May 2021 by using the search terms ('de-escalation' OR 'switching') AND ('antiplatelet' OR 'clopidogrel' OR 'ticagrelor' OR 'prasugrel') AND ('percutaneous coronary intervention' OR 'PCI'' OR 'Acute coronary syndrome' OR 'ACS').

STUDY SELECTION AND DATA EXTRACTION

We included RCTs that reported the primary outcomes, i.e. net clinical benefits and Bleeding Academic Research Consortium (BARC) type 2 or higher bleeding. A combination of both ischemic and bleeding events was defined as a net clinical benefit.

DATA SYNTHESIS

A total of four RCTs were included, with 5952 patients. A random-effects meta-analysis revealed that a de-escalation strategy was associated with lower ischemic and bleeding events (net clinical benefits; risk ratio [RR] 0.63, 95% confidence interval [CI] 0.47-0.85; p = 0.003), and lower BARC type 2 or higher bleeding (RR 0.51, 95% CI 0.29-0.91; p = 0.02) when compared with a continuation strategy.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

The current guidelines recommend potent P2Y12 prasugrel or ticagrelor for 12 months despite their association with a high risk of bleeding. Our meta-analysis updates cardiologists, providing them with the best available evidence in managing patients with ACS who underwent PCI.

CONCLUSION

Among patients with ACS treated with PCI, a de-escalation strategy (prasugrel or ticagrelor to clopidogrel) is associated with lower ischemic and bleeding events (net clinical benefits) and lower BARC type 2 or higher bleeding; however, due to the limited number of included studies, further high-quality studies are needed to establish the clinical efficacy of the de-escalation strategy.

Effect of Antiplatelet Therapy on Survival and Organ Support-Free Days in Critically Ill Patients With COVID-19: A Randomized Clinical Trial

Importance

The efficacy of antiplatelet therapy in critically ill patients with COVID-19 is uncertain.

Objective

To determine whether antiplatelet therapy improves outcomes for critically ill adults with COVID-19.

Design, Setting, and Participants

In an ongoing adaptive platform trial (REMAP-CAP) testing multiple interventions within multiple therapeutic domains, 1557 critically ill adult patients with COVID-19 were enrolled between October 30, 2020, and June 23, 2021, from 105 sites in 8 countries and followed up for 90 days (final follow-up date: July 26, 2021).

Interventions

Patients were randomized to receive either open-label aspirin (n = 565), a P2Y12 inhibitor (n = 455), or no antiplatelet therapy (control; n = 529). Interventions were continued in the hospital for a maximum of 14 days and were in addition to anticoagulation thromboprophylaxis.

Main Outcomes and Measures

The primary end point was organ support-free days (days alive and free of intensive care unit-based respiratory or cardiovascular organ support) within 21 days, ranging from -1 for any death in hospital (censored at 90 days) to 22 for survivors with no organ support. There were 13 secondary outcomes, including survival to discharge and major bleeding to 14 days. The primary analysis was a bayesian cumulative logistic model. An odds ratio (OR) greater than 1 represented improved survival, more organ support-free days, or both. Efficacy was defined as greater than 99% posterior probability of an OR greater than 1. Futility was defined as greater than 95% posterior probability of an OR less than 1.2 vs control. Intervention equivalence was defined as greater than 90% probability that the OR (compared with each other) was between 1/1.2 and 1.2 for 2 noncontrol interventions.

Results

The aspirin and P2Y12 inhibitor groups met the predefined criteria for equivalence at an adaptive analysis and were statistically pooled for further analysis. Enrollment was discontinued after the prespecified criterion for futility was met for the pooled antiplatelet group compared with control. Among the 1557 critically ill patients randomized, 8 patients withdrew consent and 1549 completed the trial (median age, 57 years; 521 [33.6%] female). The median for organ support-free days was 7 (IQR, -1 to 16) in both the antiplatelet and control groups (median-adjusted OR, 1.02 [95% credible interval {CrI}, 0.86-1.23]; 95.7% posterior probability of futility). The proportions of patients surviving to hospital discharge were 71.5% (723/1011) and 67.9% (354/521) in the antiplatelet and control groups, respectively (median-adjusted OR, 1.27 [95% CrI, 0.99-1.62]; adjusted absolute difference, 5% [95% CrI, -0.2% to 9.5%]; 97% posterior probability of efficacy). Among survivors, the median for organ support-free days was 14 in both groups. Major bleeding occurred in 2.1% and 0.4% of patients in the antiplatelet and control groups (adjusted OR, 2.97 [95% CrI, 1.23-8.28]; adjusted absolute risk increase, 0.8% [95% CrI, 0.1%-2.7%]; 99.4% probability of harm).

Conclusions and Relevance

Among critically ill patients with COVID-19, treatment with an antiplatelet agent, compared with no antiplatelet agent, had a low likelihood of providing improvement in the number of organ support-free days within 21 days.

Trial Registration

ClinicalTrials.gov Identifier: NCT02735707.