[Articles] Aspirin versus Clopidogrel for Chronic Maintenance Monotherapy After Percutaneous Coronary Intervention: 10-Year Follow-Up of the HOST-EXAM Trial

Why It Matters

Replacing aspirin with clopidogrel could improve ischemic and bleeding outcomes for millions of post‑PCI patients, influencing guideline recommendations and prescribing habits worldwide.

Key Takeaways

• Clopidogrel reduced primary composite events vs aspirin
• Hazard ratio 0.86, p=0.005
• Bleeding rates lower with clopidogrel
• No mortality difference observed
• 10‑year follow‑up with 92.8% completion

Pulse Analysis

Long‑term antiplatelet therapy after percutaneous coronary intervention (PCI) has traditionally relied on low‑dose aspirin once dual therapy ends, despite growing concerns about aspirin‑related gastrointestinal bleeding and variable efficacy. Recent guideline updates have begun to entertain P2Y12 inhibitor monotherapy, but robust data extending beyond a few years have been scarce. The original HOST‑EXAM trial, published in 2021, hinted at a modest advantage for clopidogrel, yet clinicians have awaited definitive evidence over a decade to justify a shift in standard practice.

The 10‑year extension of HOST‑EXAM delivers that evidence, enrolling over 5,400 patients who completed at least six months of uneventful dual antiplatelet therapy. Clopidogrel achieved a 25.4% event rate for the composite endpoint compared with 28.5% for aspirin, translating to a hazard ratio of 0.86 and a statistically significant p‑value of 0.005. The number‑needed‑to‑treat (NNT) to prevent one composite event approximates 36, while reductions in thrombotic (17.3% vs 20.0%) and major bleeding outcomes (9.1% vs 10.8%) further underscore its clinical relevance. Subgroup analyses revealed consistent benefits across age, diabetes status, and complex PCI sub‑populations, suggesting broad applicability.

For clinicians, these results signal a potential paradigm shift: clopidogrel may become the preferred long‑term monotherapy after PCI, especially in patients at higher bleeding risk or those intolerant to aspirin. Practical considerations include CYP2C19 genotype testing, which can affect clopidogrel responsiveness, and cost differentials that vary by region. Nevertheless, the safety profile and ease of once‑daily dosing make clopidogrel an attractive alternative. Future research should explore head‑to‑head comparisons with newer P2Y12 inhibitors and assess real‑world adherence patterns, but the HOST‑EXAM decade‑long data already provide a compelling case for updating practice guidelines and prescribing habits.