Ticagrelor monotherapy versus aspirin monotherapy at 12 months after percutaneous coronary intervention: a landmark analysis of the GLOBAL LEADERS trial

Monotherapy with P2Y12-inhibitors after dual antiplatelet therapy: Filling gaps in evidence

BACKGROUND

Whether P2Y12 inhibitor monotherapy (P2Y12-I) is superior to aspirin following DAPT discontinuation post-PCI remains to be established.

METHODS

We updated our prior network meta-analysis where P2Y12-I and aspirin had been compared with DAPT or directly with each other. The focus is specifically on the available direct evidence, now consisting of the three head-to-head comparisons of P2Y12-I and aspirin in event-free PCI patients after DAPT. We include a Trial Sequential Analysis of the direct evidence based on meta-analytical literature.

RESULTS

The main finding reveals a 39% significantly lower risk of myocardial infarction with P2Y12-I (RR 0.61, 95% CI 0.47-0.78, p = 0.0001, I2 = 0%) with no difference in bleeding. Trial Sequential Analysis demonstrates clinically meaningful evidence for a reduction in the incidence of myocardial infarction with P2Y12-I that is also supported by statistical significance.

CONCLUSIONS

Accruing data highlight that P2Y12-I following DAPT discontinuation after PCI is associated with lower risk for MI and a similar risk for bleeding as compared with ASA. In light of potential limitations to the widespread adoption of life-long P2Y12-I treatment, clinicians should consider identifying selected patients who are expected to derive the highest benefit.

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.

Clopidogrel vs Aspirin Monotherapy Beyond 1 Year After Percutaneous Coronary Intervention

BACKGROUND

It remains unclear whether clopidogrel is better suited than aspirin as the long-term antiplatelet monotherapy following dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI).

OBJECTIVES

This study compared clopidogrel monotherapy following 1 month of DAPT (clopidogrel group) with aspirin monotherapy following 12 months of DAPT (aspirin group) after PCI for 5 years.

METHODS

STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy 2) is a multicenter, open-label, adjudicator-blinded, randomized clinical trial conducted in Japan. Patients who underwent PCI with cobalt-chromium everolimus-eluting stents were randomized in a 1-to-1 fashion either to clopidogrel or aspirin groups. The primary endpoint was a composite of cardiovascular outcomes (cardiovascular death, myocardial infarction, stroke, or definite stent thrombosis) or major bleeding (TIMI major or minor bleeding).

RESULTS

Among 3,005 study patients (age: 68.6 ± 10.7 years; women: 22.3%; acute coronary syndrome: 38.3%), 2,934 patients (97.6%) completed the 5-year follow-up (adherence to the study drugs at 395 days: 84.7% and 75.9%). The clopidogrel group compared with the aspirin group was noninferior but not superior for the primary endpoint (11.75% and 13.57%, respectively; HR: 0.85; 95% CI: 0.70-1.05; Pnoninferiority < 0.001; Psuperiority = 0.13), whereas it was superior for the cardiovascular outcomes (8.61% and 11.05%, respectively; HR: 0.77; 95% CI: 0.61-0.97; P = 0.03) and not superior for major bleeding (4.44% and 4.92%, respectively; HR: 0.89; 95% CI: 0.64-1.25; P = 0.51). By the 1-year landmark analysis, clopidogrel was numerically, but not significantly, superior to aspirin for cardiovascular events (6.79% and 8.68%, respectively; HR: 0.77; 95% CI: 0.59-1.01; P = 0.06) without difference in major bleeding (3.99% and 3.32%, respectively; HR: 1.23; 95% CI: 0.84-1.81; P = 0.31).

CONCLUSIONS

Clopidogrel might be an attractive alternative to aspirin with a borderline ischemic benefit beyond 1 year after PCI.

Comparison of Different Chronic Maintenance Antithrombotic Strategies in Patients with Coronary Artery Disease: A Systematic Review and Network Meta-Analysis

Background

Optimal antithrombotic therapy during the chronic maintenance period in patients with coronary artery disease (CAD) is unknown. We compared five kinds of mainstream chronic maintenance antithrombotic strategies at least one year after the acute phase: aspirin alone, clopidogrel alone, ticagrelor alone, continued dual antiplatelet therapy (DAPT) for a period of time, and maintenance with aspirin combined with a low-dose anticoagulant such as rivaroxaban.

Methods

Ten randomized, controlled trials were selected using PubMed, Ovid MEDLINE, Embase, and Cochrane library through February 2023. The primary outcome was main adverse cardiac events (MACEs), and secondary outcomes include net adverse clinical events (NACEs), cardiac death, all-cause death, ischemic stroke, stent thrombosis, total bleeding, and major bleeding. A network meta-analysis was conducted with a random-effects model. Data extraction was performed by three independent reviewers.

Results

Our search identified ten eligible randomized controlled trials enrolling a total of 82,084 patients comparing different chronic maintenance antithrombotic strategies. As for the primary endpoint, there was no statistical difference in MACE outcomes between any two of the five methods. As for the secondary endpoint, there was no statistical difference in NACE, major bleeding, all-cause death, cardiac death, and stent thrombosis between any two methods. The aspirin plus low-dose rivaroxaban group had a lower incidence of ischemic stroke compared to the aspirin group (OR = 0.49, 95% CrI 0.26-0.91). And the prolonged DAPT group had a higher total bleeding rate compared to aspirin group (OR = 2.4, 95% CrI 1.1-5.9).

Conclusions

In terms of MACE, NACE, all-cause death, cardiac death, stent thrombosis, and major bleeding, there were no significant differences between using aspirin alone, clopidogrel alone, and ticagrelor alone; extending DAPT duration; and using aspirin combined with low-dose rivaroxaban for chronic maintenance antithrombotic regimens. However, choosing aspirin combined with low-dose rivaroxaban can reduce the incidence of ischemic stroke, and prolonged DAPT may have a higher rate of total bleeding. However, it is important to note that this study is based on indirect comparisons, and there is currently a lack of direct evidence comparing various maintenance antiplatelet therapy regimens. Further high-quality studies are needed to address this gap and provide more conclusive evidence on the comparative effectiveness of different maintenance antiplatelet strategies.

Antiplatelet Therapy Aims and Strategies in Asian Patients with Acute Coronary Syndrome or Stable Coronary Artery Disease

Dual antiplatelet therapy (DAPT) has been the mainstay treatment to reduce ischemic events, such as myocardial infarction or stroke, in patients with coronary artery disease (CAD). The development of potent P2Y12 inhibitors (ticagrelor and prasugrel) has helped to further reduce ischemic events, particularly among high-risk patients. Meanwhile, the evolution of newer generations of drug-eluting stents are also improving outcomes of percutaneous coronary intervention. Research studies on antiplatelet therapy in recent years have focused on balancing ischemic and bleeding risks through different strategies, which include P2Y12 inhibitor monotherapy, escalation and de-escalation, and extended DAPT. Because results from the large number of clinical studies may sometimes appear conflicting, this review aims to summarize recent advances, and demonstrate that they are aligned by a general principle, namely, strategies may be adopted based on treatment aims for specific patients at several time points. Another aim of this review is to outline the important considerations for using antiplatelet therapy in Asian patients, in whom there is a greater prevalence of CYP2C19 loss-of-function mutations, and a common increased risk of bleeding, despite high platelet reactivity (the so-called "East Asian Paradox").

P2Y12 inhibitor monotherapy in patients undergoing percutaneous coronary intervention

For 20 years, dual antiplatelet therapy (DAPT), consisting of the combination of aspirin and a platelet P2Y₁₂ receptor inhibitor, has been the gold standard of antithrombotic pharmacology after percutaneous coronary intervention (PCI). In the past 5 years, several investigations have challenged this paradigm by testing the efficacy and safety of P2Y₁₂ inhibitor monotherapy (that is, without aspirin) following a short course of DAPT. Collectively, these studies suggested a reduction in the risk of major bleeding and no significant increase in thrombotic or ischaemic events compared with guideline-recommended DAPT. Current recommendations are evolving to inform clinical practice on the ideal candidates for P2Y₁₂ inhibitor monotherapy after PCI. Generalizing the results of studies of P2Y₁₂ inhibitor monotherapy requires a thorough understanding of their design, populations, interventions, comparators and results. In this Review, we provide an up-to-date overview on the use of P2Y₁₂ inhibitor monotherapy after PCI, including supporting pharmacodynamic and clinical evidence, practical recommendations and future directions.

Long-term Effects of P2Y12 Inhibitor Monotherapy After Percutaneous Coronary Intervention: 3-Year Follow-up of the SMART-CHOICE Randomized Clinical Trial

Importance

Although P2Y12 inhibitor monotherapy after a minimum period of dual antiplatelet therapy (DAPT) is a well-known way to reduce the risk of bleeding after percutaneous coronary intervention (PCI), data comparing long-term clinical outcomes between P2Y12 inhibitor monotherapy and extended DAPT in patients undergoing PCI have been unavailable.

Objective

To identify the long-term safety and efficacy of P2Y12 inhibitor monotherapy following 3 months of DAPT after PCI.

Design, Setting, and Participants

The Smart Angioplasty Research Team: Comparison Between P2Y12 Antagonist Monotherapy and Dual Antiplatelet Therapy in Patients Undergoing Implantation of Coronary Drug-Eluting Stents (SMART-CHOICE) trial was an open-label, noninferiority, randomized clinical trial, enrolling patients who underwent PCI with drug-eluting stent at 33 hospitals in Korea from March 2014 through July 2017. Clinical follow-up was extended to 3 years and completed in August 2020.

Interventions

Patients were randomly assigned to either P2Y12 inhibitor monotherapy after 3 months of DAPT or DAPT for 12 months or longer.

Main Outcomes and Measures

The primary end point was major adverse cardiac and cerebrovascular events (a composite of all-cause death, myocardial infarction, or stroke) at 3 years. The secondary end points included the components of the primary end point, bleeding (defined as Bleeding Academic Research Consortium [BARC] types 2-5), and major bleeding (BARC types 3-5).

Results

In total, 2993 patients were randomly assigned to receive P2Y12 inhibitor monotherapy after 3 months of DAPT (1495 patients [50%]; mean [SD] age, 64.6 [10.7] years; 1087 [72.7%] male) or prolonged DAPT (1498 patients [50%]; mean [SD] age, 64.6 [10.7] years; 1111 [74.2%] male) after PCI. At 3 years, the primary end point occurred in 87 individuals (6.3%) in the P2Y12 inhibitor monotherapy group and 83 (6.1%) in the prolonged DAPT group (hazard ratio [HR], 1.06 [95% CI, 0.79-1.44]; P = .69). P2Y12 inhibitor monotherapy significantly reduced the risk of bleeding (BARC types 2-5: 112 [3.2%] vs 44 [8.2%]; HR, 0.39 [95% CI, 0.28-0.55]; P < .001) and major bleeding (BARC types 3-5; 17 [1.2%] vs 31 [2.4%]; HR, 0.56 [95% CI, 0.31-0.99]; P = .048), compared with prolonged DAPT. The landmark analyses between 3 months and 3 years and per-protocol analyses showed consistent results.

Conclusions and Relevance

Among patients who underwent PCI and completed 3-month DAPT, P2Y12 inhibitor monotherapy was associated with a lower risk of clinically relevant major bleeding than prolonged DAPT. Although the 3-year risk of ischemic cardiovascular events was comparable between the 2 groups, this result should be interpreted with caution owing to the limited number of events and sample size.

Trial Registration

ClinicalTrials.gov Identifier: NCT02079194.

P2Y12 Inhibitor Monotherapy after Percutaneous Coronary Intervention

In patients with acute and chronic coronary artery disease undergoing percutaneous coronary intervention (PCI), dual antiplatelet therapy (DAPT) has been the cornerstone of pharmacotherapy for the past two decades. Although its antithrombotic benefit is well established, DAPT is associated with an increased risk of bleeding, which is independently associated with poor prognosis. The improvement of the safety profiles of drug-eluting stents has been critical in investigating and implementing shorter DAPT regimens. The introduction into clinical practice of newer generation oral P2Y₁₂ inhibitors such as prasugrel and ticagrelor, which provide more potent and predictable platelet inhibition, has questioned the paradigm of standard DAPT durations after coronary stenting. Over the last five years, several trials have assessed the safety and efficacy of P2Y₁₂ inhibitor monotherapy after a short course of DAPT in patients treated with PCI. Moreover, ongoing studies are testing the role of P2Y₁₂ inhibitor monotherapy immediately after PCI in selected patients. In this review, we provide up-to-date evidence on the efficacy and safety of P2Y₁₂ inhibitor monotherapy after a short period of DAPT compared to DAPT in patients undergoing PCI as well as outcomes associated with P2Y₁₂ inhibitor monotherapy compared to aspirin for long-term prevention.