Rivaroxaban for stroke patients with antiphospholipid syndrome (RISAPS): protocol for a randomized controlled, phase IIb proof-of-principle trial.
Research article published in Research and practice in thrombosis and haemostasis (2024)
Abstract
BACKGROUND: Optimal secondary prevention antithrombotic therapy for patients with antiphospholipid syndrome (APS)-associated ischemic stroke, transient ischemic attack, or other ischemic brain injury is undefined. The standard of care, warfarin or other vitamin K antagonists at standard or high intensity (international normalized ratio (INR) target range 2.0-3.0/3.0-4.0, respectively), has well-recognized limitations. Direct oral anticoagulants have several advantages over warfarin, and the potential role of high-dose direct oral anticoagulants vs high-intensity warfarin in this setting merits investigation. OBJECTIVES: The Rivaroxaban for Stroke patients with APS trial (RISAPS) seeks to determine whether high-dose rivaroxaban could represent a safe and effective alternative to high-intensity warfarin in adult patients with APS and previous ischemic stroke, transient ischemic attack, or other ischemic brain manifestations. METHODS: This phase IIb prospective, randomized, controlled, noninferiority, open-label, proof-of-principle trial compares rivaroxaban 15 mg twice daily vs warfarin, target INR range 3.0-4.0. The sample size target is 40 participants. Triple antiphospholipid antibody-positive patients are excluded. The primary efficacy outcome is the rate of change in brain white matter hyperintensity volume on magnetic resonance imaging, a surrogate marker of presumed ischemic damage, between baseline and 24 months follow-up. Secondary outcomes include additional neuroradiological and clinical measures of efficacy and safety. Exploratory outcomes include high-dose rivaroxaban pharmacokinetic modeling. CONCLUSION: Should RISAPS demonstrate noninferior efficacy and safety of high-dose rivaroxaban in this APS subgroup, it could justify larger prospective randomized controlled trials.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Optimal secondary prevention antithrombotic therapy for patients with antiphospholipid syndrome (APS)-associated ischemic stroke, transient ischemic attack, or other ischemic brain injury is undefined.
Why This Matters for Hirudotherapy
This is the published protocol for RISAPS, a phase IIb, prospective, randomized, controlled, open-label, non-inferiority proof-of-principle trial (sample-size target 40, with triple antiphospholipid-antibody-positive patients excluded) comparing high-dose rivaroxaban 15 mg twice daily against high-intensity warfarin (target INR 3.0-4.0) for secondary prevention in antiphospholipid-syndrome patients with prior ischemic stroke or other ischemic brain manifestations, with the primary efficacy outcome being the rate of change in brain white-matter-hyperintensity volume on MRI between baseline and 24 months. For the ASH evidence picture it illustrates the ongoing clinical effort to find safer, effective anticoagulation in a high-thrombotic-risk population, the same unmet-need landscape that motivates interest in leech-secretome anticoagulants as alternative mechanisms of thrombin inhibition. Caveat: this is only a trial protocol, not results, so it reports no efficacy or safety findings; the study is small, preliminary by design, and entirely unrelated to leeches or hirudotherapy, bearing only as background on anticoagulation drug development.
Citation
Rivaroxaban for stroke patients with antiphospholipid syndrome (RISAPS): protocol for a randomized controlled, phase IIb proof-of-principle trial.
Mittal P et al. · Research and practice in thrombosis and haemostasis, 2024
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