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Clopidogrel versus aspirin for secondary prevention of coronary artery disease: a systematic review and individual patient data meta-analysis

M. Valgimigli, K. Choi, D. Giacoppo, F. Gragnano, Takeshi Kimura, Hirotoshi Watanabe, Hyo-Soo Kim, Jeehoon Kang et al.

The Lancet, 2025

28 participants · 74 citations

Abstract

BACKGROUND

Aspirin monotherapy is recommended indefinitely for patients with established coronary artery disease (CAD). The aim of this individual patient level meta-analysis was to provide a comprehensive evaluation of the comparative efficacy and safety of clopidogrel versus aspirin monotherapy in patients with established CAD, most of whom had undergone percutaneous coronary intervention or had acute coronary syndrome.

METHODS

We conducted a systematic search in PubMed, Scopus, Web of Science, and Embase to identify randomised trials published from database inception to April 12, 2025, comparing clopidogrel monotherapy with aspirin monotherapy in patients with established CAD who had discontinued or never started dual antiplatelet therapy. Randomised trials featuring an initial phase of dual antiplatelet therapy were eligible for inclusion in this individual patient data meta-analysis. In the main analysis, we used semi-parametric shared log-normal frailty models (one-stage analysis), including a random intercept to account for differences in the baseline hazard across trials, and a random slope to account for between-trial differences in treatment effects. The primary efficacy endpoint was a composite of cardiovascular death, myocardial infarction, or stroke (major adverse cardiovascular or cerebrovascular events [MACCE]); the primary safety endpoint was major bleeding. This study is registered with PROSPERO (CRD42025645594).

FINDINGS

Seven randomised trials including 28…

How strong is the evidence?

Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid. Reported size: 28 participants or records.

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