RIvaroxaban for Stroke Patients With AntiPhospholipid Syndrome

Rivaroxaban versus warfarin for stroke patients with antiphospholipid syndrome, with or without SLE (RISAPS): a randomised, controlled, open-label, phase IIb, non-inferiority proof of principle trial. 40 patients will be randomised with a ratio of 1:1 to receive either: * Rivaroxaban 15mg twice daily orally for 24 months or * Warfarin (standard of care in the RISAPS trial) to maintain a target INR of 3.5 (range 3.0-4.0) for 24 months. The primary outcome of the trial is the rate of change in brain white matter hyperintensity (WMH) volume between baseline and 24 months follow up, assessed on brain magnetic resonance imaging (MRI), a surrogate marker of ischaemic damage.

The RISAPS trial follows on from the RAPS (Rivaroxaban in Antiphospholipid Syndrome) study that showed that rivaroxaban could offer a potentially effective alternative to warfarin for patients with antiphospholipid syndrome (APS) who have thrombosis (blood clots) in their veins, rather than in their arteries and require standard intensity anticoagulation (blood thinning). Currently, APS patients who have had an ischaemic stroke (which occurs when blood flow to an area of brain is cut off) are treated with warfarin to reduce the risk of a recurrence. Warfarin tends to have a variable 'blood thinning' effect in patients with APS, necessitating frequent (usually weekly) INR blood tests to monitor the effect of the warfarin, which is inconvenient for patients. The RISAPS trial will compare higher intensity (higher dose) rivaroxaban versus higher intensity warfarin (current standard of care treatment) for 24 months, in APS patients, with or without lupus (systemic lupus erythematosus; SLE), requiring higher intensity anticoagulation after experiencing a stroke, a 'mini stroke' (also known as a transient ischaemic attack) or other ischaemic brain damage (caused by blood clots in the brain arteries or smaller blood vessels). When compared with warfarin, a dvantages of rivaroxaban include, fixed dose prescribing and no need for monitoring of anticoagulant effect. Furthermore, rivaroxaban has fewer drug-food interactions, and significantly fewer drug-drug interactions than warfarin. If rivaroxaban is no worse than warfarin for anticoagulation of APS patients with stroke or other ischaemic brain manifestations, it could become the standard of care for the treatment of APS patients, with or without lupus, who have experienced stroke or other ischaemic brain manifestations and improve patients' quality of life.