Critique of Apixaban Versus Warfarin in Patients With Atrial Fibrillation

Inferiors revolt in order that they may be equal, and equals that they may be superior. Such is the state of mind, which creates revolutions. —Aristotle. In: Politics. Book V; Part II; 350 B.C.E.For stroke prevention in atrial fibrillation (AF), warfarin has been the king of the castle for more than half a century. Recently, some serious contenders have threatened its dominance by claiming therapeutic equivalence and a better benefit–risk profile. These novel agents, oral direct thrombin or factor Xa inhibitors, have kindled anticipation of “a new era for anticoagulation in AF.”1On August 28, 2011, the New England Journal of Medicine published online the primary results of the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation trial (ARISTOTLE; ClinicalTrials.gov number NCT00412984).2 The study demonstrated convincing evidence of the benefits of the direct factor Xa inhibitor apixaban (Eliquis; Pfizer/Bristol-Myers Squibb) over warfarin in patients with AF. Before apixaban, 2 other novel anticoagulants, dabigatran and rivaroxaban, made it through phase III trials3,4 and were subsequently approved by the Food and Drug Administration. Apixaban, however, was the first new anticoagulant to achieve reductions in each of the major outcomes of stroke, bleeding, and mortality. After the publication of ARISTOTLE, it looks as we have found a successor to the throne. Beating Warfarin Is a ChallengeWafarin, the classic anticoagulation, is highly effective in preventing stroke in the context of AF and is less expensive than the novel drugs. Still, many patients and physicians have longed for alternatives that are as effective but more convenient to use.The novel agents present numerous advantages over wafarin. Their more selective mode of action (ie, targeting a single …