Benefit–risk of colchicine and spironolactone in acute myocardial infarction: a prespecified generalised pairwise comparisons analysis of the CLEAR trial

Background: Composite outcomes in cardiovascular trials often group events of unequal clinical importance, and conventional analyses may obscure treatment trade-offs. Generalised pairwise comparisons (GPC), expressed as a win ratio (WR), allow for hierarchical ranking of events and incorporation of recurrent outcomes, providing a potentially more intuitive assessment of benefit-risk.

Methods: In a prespecified exploratory analysis of the 2×2 factorial, randomised CLEAR (Colchicine and Spironolactone in Patients with Myocardial Infarction) trial (7062 patients within 72 hours of acute myocardial infarction (MI) and percutaneous coronary intervention), we applied both time-to-first and recurrent-event GPC to reassess low-dose colchicine (0.5 mg daily) and spironolactone (25 mg daily) versus placebo. For the colchicine comparison, the hierarchical benefit-risk outcome included all-cause death, stroke, recurrent MI, unplanned ischaemia-driven revascularisation, serious infection or diarrhoea. For the spironolactone comparison, the outcome included all-cause death, stroke, MI, new or worsening heart failure, significant ventricular arrhythmia, hyperkalaemia or gynaecomastia/gynaecodynia. GPC results were compared with Cox, logistic and Andersen-Gill models.

Results: For colchicine, the time-to-first event GPC showed a 12% lower proportional win rate compared with placebo (WR 0.88, 95% CI 0.79 to 0.98; win difference -2.10%, 95% CI -3.84 to -0.37), driven largely by excess diarrhoea. For spironolactone, patients experienced a 14% lower win rate (WR 0.86, 95% CI 0.75 to 0.99; win difference -1.46%, 95% CI -2.84% to -0.08%), largely attributable to gynaecomastia and hyperkalaemia. Conventional statistical approaches yielded concordant results. Across both interventions, higher-order efficacy outcomes (death, MI, stroke, heart failure) showed no benefit.

Conclusions: In patients with post-MI, both low-dose colchicine and spironolactone demonstrated disadvantageous benefit-risk profiles, reinforcing that neither agent should be used routinely. This prespecified application of GPC provided results consistent with traditional methods but offered a clinically intuitive framework for interpreting composite outcomes.