NOVEMBER CPE Article Review of Direct Acting Oral Anticoagulants Authors: Kaylee Hall, PharmD Candidate 2022; Jordan Spurling, PharmD Candidate 2022; Mark Huffmyer, PharmD, BCGP, BCACP, CACP The authors declare that there are no financial relationships that could be perceived as real or apparent conflicts of interest. Universal Activity # 0143-0000-20-011-H01-P &T 2.5 Contact Hours Expires 12/14/23 Learning Objectives: At the conclusion of this Knowledge-based article, the reader should be able to: 1.
Understand the mechanism of actions, approved indications, side effects, reversal agents, drug-drug interactions and drug-food interactions of DOACs.
2.
Evaluate the use of DOACs in special populations.
3.
Evaluate peri-procedural management of DOACs.
4. Compare and contrast DOACs to warfarin
Introduction For decades, warfarin, a vitamin K antagonist, was the only oral anticoagulant available on the market in the United States. While effective at treating and preventing thromboembolic events, warfarin requires close monitoring due to its narrow therapeutic index, which is further complicated by its many drug-drug and drug-diet interactions. This makes it cumbersome and costly to manage [1]. In 2010, a new oral anticoagulant with a novel mechanism of action was approved and several drugs have followed since then. Direct acting oral anticoagulants (DOACs), include dabigatran, rivaroxaban, apixaban, edoxaban and betrixaban, so called because of their direct mechanism of action. Warfarin exhibits its affect by depleting functional vitamin K reserves and therefore, reducing the synthesis of vitamin K dependent clotting factors [2]. DOACs, sometimes referred to as non-vitamin K dependent or novel oral anticoagulants (NOACs), act directly on specific clotting factors to produce their anticoagulant effect. Since the approval of the DOACs, there has been a declining use of warfarin each year while the use of DOACs continue to rise [3]. |10| Kentucky Pharmacists Association | November/December 2020
Compared to warfarin, DOACs require less monitoring, have less drug-drug interactions, drug-diet interactions, and can reduce the risk of hemorrhage [4]. These advantages have made DOACs the recommended treatment over warfarin for DVT/PE by the CHEST Guidelines [5] and recommended for stroke prevention in non-valvular atrial fibrillation by the American College of Cardiology [6]. In this article, we will discuss the mechanisms of action, side effects, drug-drug interactions, drug-diet interactions, reversal agents, periprocedural management and special populations of DOACs and, in addition, how they compare to warfarin. We will focus on the four most commonly prescribed DOACs, dabigatran, rivaroxaban, apixaban and edoxaban. These medications are often seen in the pharmacy and are considered to be high-risk medications by the Institute for Safe Medication Practices (ISMP) due to the risk of bleeding associated with them [7]. Understanding the DOACs, their properties and side effects can help to improve on patient care by expanding the knowledge of community pharmacists.
