Mortality benefit in the COMPASS trial: is it related to superior statistical power or better efficacy and safety?

Until recently, attempts to improve the benefit of aspirin by adding another antithrombotic agent have not resulted in a mortality reduction in patients with chronic symptomatic atherosclerosis. In this population, COMPASS is the only one among six trials to show a significant mortality reduction, thereby providing evidence of a clear net clinical benefit with the combination of low-dose rivaroxaban plus aspirin. In this systematic review, we sought to determine whether the mortality benefit of the combination arm in COMPASS is best explained by greater statistical power or by a more favorable efficacy-safety profile than the other regimens evaluated in patients with chronic symptomatic atherosclerosis.