Novel Oral Anticoagulants, A Subject in Continuing Debate

Coumarin anticoagulants era (warfarin, acenocumarol) seems to be coming to an end with the launch of the novel anticoagulants like dabigatran, rivaroxaban, apixaban and edoxaban. Dabigatran (Pradaxa) is a prothrombin (factor II) inhibitor that doesn't necessitate monitoring by coagulation tests, doesn't have food or drug interactions, except for P-gp inhibitors. Rivaroxaban (Xarelto) is a direct inhibitor of factor X and is approved for the prevention of thromboembolic events in patients with non-valvular atrial fibrillation and for the prevention of deep venous thrombosis in patients undergoing orthopaedic surgery (hip and knee prosthesis). Apixaban (Eliquis) is a direct inhibitor of factor X and is indicated for the prevention of venous thromboembolic events in patients undergoing hip or knee arthroplasty, the prevention of thromboembolic events in patients with non-valvular atrial fibrillation and treatment or prevention of recurrences in patients with deep vein thrombosis or pulmonary embolism. Edoxaban (Savaysa), recently approved is USA, is a direct inhibitor of factor X and is indicated for deep venous thrombosis, pulmonary embolism and for the prevention of thromboembolic events in patients with non-valvular atrial fibrillation. The most recent studies focus on antidotes specifically designed to bind and neutralise the anticoagulant activity of both direct thrombin inhibitors and direct factor Xa inhibitors. The drugs currently being studied are idarucizumab, a specific antidote, andexanet alfa, a class-specific antidote and ciraparantag, a universal antidote. Of these, only idarucizumab was approved by the FDA.