Effectiveness and safety of the direct oral anticoagulants in non-triple positive antiphospholipid syndrome without prior arterial thromboembolism

Rethinking the use of direct oral anticoagulants for secondary thromboprophylaxis in patients with thrombotic antiphospholipid syndrome

Patients with thrombotic antiphospholipid syndrome (APS) are at high risk for recurrent thrombosis, and indefinite anticoagulation is recommended. Patients with APS merit indefinite anticoagulation, and vitamin K antagonists (VKAs) have historically been the standard treatment. Direct oral anticoagulants (DOACs) present an appealing alternative to VKAs. Due to their pharmacokinetic and pharmacodynamic characteristics, DOACs offer advantages over VKAs, namely the lack of need for laboratory monitoring, the usage of a fixed dosage, and the absence of significant interaction with dietary components and drugs. The efficacy and safety of DOACs in patients with APS have been studied in four phase II/III clinical trials (three with rivaroxaban and one with apixaban). These studies showed DOACs' inferiority compared to VKAs in preventing recurrent thrombosis. Recurrence was significantly greater in patients with arterial thrombotic events and a triple positivity for antiphospholipid antibodies. No differences were observed in the incidence of venous thromboembolism between both groups. Major bleeding was similar in patients treated with DOACs or VKAs. Several observational studies have reported similar results. This review aims to analyse the existing evidence on the efficacy and safety of DOACs for secondary prevention in patients with APS.

Thromboembolic Antiphospholipid Syndrome (APS): Efficacy and Safety of Different Anticoagulants-Results of the APSantiCO Registry

Background: The particular challenge in dealing with patients with thromboembolic antiphospholipid syndrome (APS) is to establish an adequate therapy regime, as patients suffer from an increased risk of relapse despite antithrombotic treatment (ATT). Vitamin K antagonists (VKA) are the standard medication of choice. The current data on the use of direct oral anticoagulants (DOAC) in APS patients remain limited. Methods: The results of the retrospective APSantiCO registry are presented. In 80 patients with APS, the efficacy and safety of different ATT regimens were analyzed. Results: At the time of inclusion, 43.8% of patients were treated with VKA and 36.3% with DOAC. Medication regimes changed several times and 279 treatment phases were further analyzed with a total treatment length of 7529 months. The incidence of recurrent arterial thrombosis was significantly larger in the DOAC group compared with the VKA group (p < 0.001), while the incidence of recurrent venous thrombosis was comparable between both groups, as was the incidence of bleedings. Heavy menstrual bleeding was the most frequently observed bleeding complication. Conclusions: The data suggest that DOAC may be an alternative to VKA for APS patients with venous thromboembolism, while VKA should be used in APS-related arterial thrombosis.