[A new anticoagulant strategy: the factor XI inhibitors]

In the last 10 years the introduction of the direct oral anticoagulants (DOACs) has revolutionized the anticoagulant treatment, one of the cornerstones of the therapy for cardiovascular diseases. Thanks to their efficacy at least not inferior compared to vitamin K antagonists and their better safety profile, particularly with regard to intracranial bleeding, DOACs are now the first choice for the prevention of cardioembolism in patients with non-valvular atrial fibrillation and for the treatment of venous thromboembolism (VTE). Other areas of clinical use for DOACs include the prevention of VTE in orthopedic and oncology surgery and in outpatient cancer patients treated with anticancer therapy, or the use of low-dose in association with aspirin in patients with coronary or peripheral artery disease.An increased risk of gastrointestinal bleeding has been reported for some DOACs. In addition, DOACs have also experienced some failures including stroke prevention in patients with mechanical prosthetic valves or rheumatic diseases and VTE therapy in patients with antiphospholipid antibody syndrome. Also, no data are available on DOACs in some particular areas, including severe renal impairment and thrombocytopenia.In recent years, the clinical use of factor XI and factor XII inhibitors has been proposed. Currently, factor XI inhibitors have more clinical data than factor XII inhibitors. This article will report the rationale for the clinical use and the main evidences currently available on factor XI inhibitors.