[Factor XI inhibitors: the holy grail of anticoagulant therapy?].

Direct-acting oral anticoagulants (DOAC's) have surpassed vitamin K antagonists (VKAs) as the preferred anticoagulant therapy in patients with non-valvular atrial fibrillation or venous thromboembolism. In most patients, the benefits of anticoagulant therapy, i.e. prevention of thromboembolism including stroke risk outweigh the risks of bleeding complications. However, in older and frail patients, uptake of DOAC's is limited by concerns of bleeding. Recent developments, with therapeutics that specifically target factor XI, carry a promise to be a game changer. Activated factor XI is thought to contribute to clot progression and thrombosis, but has only a minor effect on clot consolidation during hemostasis. In this paper we will discuss the latest findings of clinical studies on factor XI inhibitors and speculate on future perspectives, including the proposal to use consistent terminology for this emerging class of DOAC's.