Rivaroxaban vs warfarin in high-risk patients with antiphospholipid syndrome

Pengo, Vittorio;Denas, Gentian;Zoppellaro, Giacomo;Padayattil Jose, Seena;Hoxha, Ariela;Ruffatti, Amelia;Andreoli, Laura;Tincani, Angela;Cenci, Caterina;Prisco, Domenico;Fierro, Tiziana;Gresele, Paolo;Cafolla, Arturo;De Micheli, Valeria;Ghirarduzzi, Angelo;Tosetto, Alberto;Falanga, Anna;Martinelli, Ida;Testa, Sophie;Barcellona, Doris;Gerosa, Maria;Banzato, Alessandra

2018-01-01

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Abstract

Rivaroxaban is an effective and safe alternative to warfarin in patients with atrial fibrillation and venous thromboembolism. We tested the efficacy and safety of rivaroxaban as compared to warfarin in high-risk patients with thrombotic Antiphospholipid Syndrome. This is a randomized, open-label, multicenter, non-inferiority study with blinded end-point adjudication. Rivaroxaban 20 mg once daily (15 mg once daily based on kidney function) was compared to warfarin (INR target 2.5), for the prevention of thromboembolic events, major bleeding and vascular death in patients with Antiphospholipid Syndrome. Only high-risk patients triple positive for Lupus Anticoagulant, anti-cardiolipin and anti-β2-glycoprotein I antibodies of the same isotype (triple-positivity) were included in the study. The trial was terminated prematurely after the enrollment of 120 patients (59 randomized to rivaroxaban and 61 to warfarin) because of an excess of events among patients in the rivaroxaban arm. Mean follow up was 569 days. There were 11 (19%) events in the rivaroxaban group and 2 (3%) in the warfarin group. Thromboembolic events occurred in 7 (12%) patients randomized to rivaroxaban (4 ischemic stroke and 3 myocardial infarction) while no event was recorded in those randomized to warfarin. Major bleeding occurred in 6 patients, 4 (7%) in the rivaroxaban and 2 (3%) in the warfarin group. No death was reported. The use of rivaroxaban in high-risk patients with Antiphospholipid Syndrome was associated with an increased rate of events as compared with warfarin, thus showing no benefit and excess risk. (ClinicalTrials.gov Identifier: NCT02157272).