TRAPS: Rivaroxaban vs Warfarin for secondary prevention of antiphospholipid syndrome [Classics Series]

This study summary is an excerpt from the book 2 Minute Medicine’s The Classics in Medicine: Summaries of Landmark Trials

1. This study was terminated early due to an excess of thromboembolic and bleeding events in patients treated with rivaroxaban compared to warfarin.

2. There were no deaths due to thromboembolic or hemorrhagic events in either group.

Original publication date: September 2018

Summary of the study: The rivaroxaban in antiphospholipid syndrome (TRAPS) trial was terminated prematurely because data showed that secondary prevention with rivaroxaban in high-risk triplicate-positive patients with antiphospholipid syndrome (aPL) was associated with a excess thromboembolic and bleeding events compared to warfarin. Thus, this trial showed that treatment with rivaroxaban in these patients was inferior to treatment with warfarin. The strengths of this study include the completeness of its dataset, with no patients lost to follow-up, and its characterization of thromboembolic and bleeding outcomes. However, this study is limited by its relatively small sample size, the fact that it was not blinded and, of course, its premature termination. Additionally, because this study was limited to a very specific subset of high-risk patients with aPL syndrome, future research is needed to determine whether these findings are generalizable to all patients with aPL syndrome. Ultimately, warfarin remains the standard of treatment for high-risk patients with aPL syndrome because rivaroxaban is associated with increased adverse clinical outcomes.

Click to read the study in Blood

In depth [randomized control trial]: The Rivaroxaban in Antiphospholipid Syndrome (TRAPS) Trial sought to test whether rivaroxaban is non-inferior to warfarin for the prevention of thromboembolic events in high-risk patients with aPL syndrome. The study included participants aged 18 to 75 who were triple positive for all 3 aPL tests (lupus anticoagulant, anti-cardiolipin antibody, and anti-b2-glycoprotein I antibody) and had a history of a previously documented thrombotic event (n=120). Participants were randomized to receive rivaroxaban (n=59) or warfarin (n=61) and were followed for incidence of thromboembolic events, major bleeding, and vascular death. The trial was stopped early due to an excess of events in patients treated with rivaroxaban compared to warfarin (11 versus 2, respectively, HR 6.7; 95% CI 1.5- 30.5; p=0.01). Events included ischemic stroke, myocardial infarction, and major bleeding. There were no venous thromboembolic events or deaths in the “as treated” population for the rivaroxaban or warfarin groups.

Pengo V, Denas G, Zoppellaro G, Jose SP, Hoxha A, Ruffatti A, et al. Rivaroxaban vs warfarin in high-risk patients with antiphospholipid syndrome. Blood. 2018 Sep 27;132(13):1365–71.

©2022 2 Minute Medicine, Inc.. All rights reserved. No work may be reproduced without the express written consent of 2 Minute Medicine, Inc.. Ask about licenses here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.


Leave a Comment