Reversing the Effect of Oral Anticoagulant Drugs: Established and Newer Options

The vitamin K antagonists (VKAs) have been the standard (and only) oral anticoagulants used for the long-term treatment or prevention of venous thromboembolism or stroke in patients with atrial fibrillation. The coagulopathy induced by VKAs can be reversed with vitamin K, and in urgent situations, the vitamin K-dependent coagulation factors can be replaced by transfusion. In the last decade, a new class of oral anticoagulants has been developed, direct oral anticoagulants that bind to a specific coagulation factor and neutralize it. These compounds were shown to be effective and safe compared with the VKAs and were licensed for specific indications, but without a specific reversal agent. The absence of a reversal agent is a barrier to more widespread use of these agents. Currently, for the management of major life-threatening bleeding with the direct oral anticoagulants, most authorities recommend the use of four factor prothrombin complex concentrates. There are now three reversal agents in development and poised to enter the market. Idarucizumab is a specific antidote targeted to reverse the direct thrombin inhibitor, dabigatran, which was recently approved for use in the USA. Andexanet alfa is an antidote targeted to reverse the oral direct factor Xa inhibitors as well as the indirect inhibitor enoxaparin. Ciraparantag is an antidote targeted to reverse the direct thrombin and factor Xa inhibitors as well as the indirect inhibitor enoxaparin.