The use of direct oral anticoagulants in 56 patients with antiphospholipid syndrome.

INTRODUCTION: Antiphospholipid syndrome (APS) is a common acquired thrombophilia associated with a high thrombotic risk, in which vitamin K antagonists (VKA) represent the mainstay of therapy. Case series involving up to 35 patients with APS suggested limited efficacy and safety of direct oral anticoagulants (DOACs). MATERIAL AND METHODS: In the prospective case series we followed 56 consecutive patients with APS (44 women and 12 men, aged from 22 to 64years), including 33 (60%) associated with systemic lupus erythematosus (SLE) and 16 (28.6%) with triple APS who were treated with DOACs due to their preferences or unstable anticoagulation with VKA. DOACs were started at least 3months since the thromboembolic event in patients with D-dimer below 500ng/ml. RESULTS: Forty-nine (87.5%) patients were treated with rivaroxaban, 4 (7.3%) with dabigatran and 3 (5.4%) with apixaban. During follow-up of 2 to 43 (mean 22) months, 6 (10.7%, 5.8 per 100 patient-years) patients (4 women and 2 men, 4 with triple positive APS) experienced recurrent thrombosis, including deep vein thrombosis (n=4, including 2 episodes preceded by nonadherence), superficial vein thrombosis (n=1) and non-ST elevation myocardial infarction (n=1). The recurrence rate of VTE on DOACs was 5.8 per 100 patient-years. Two patients (3.6%) experienced severe bleeding. CONCLUSIONS: This case-series suggests that DOACs are safe in patients with APS. These findings need to be confirmed in larger studies.