June 18, 2013Annals of Internal Medicine51 citations
Clinical Outcomes With Rivaroxaban in Patients Transitioned From Vitamin K Antagonist Therapy
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Structured PICO
Does rivaroxaban prevent stroke or systemic embolism in VKA-naive and VKA-experienced patients with atrial fibrillation compared to warfarin?
P
Population
14,264 persons with atrial fibrillation, including 7,897 (55.4%) VKA-experienced and 6,367 (44.6%) VKA-naive patients, in a global setting.
I
Intervention
Rivaroxaban
C
Comparator
Warfarin
O
Outcome
Stroke or systemic embolismcomposite
Rivaroxaban maintains consistent efficacy compared to warfarin regardless of prior VKA exposure, though it is associated with a transient increase in early bleeding risk during the first 7 days of transition.
Limitations
- The trial was not designed to detect differences in these subgroups.
Abstract
BACKGROUND: In ROCKET AF (Rivaroxaban Once-Daily, Oral, Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation), a large randomized, clinical trial, rivaroxaban was noninferior to warfarin in preventing stroke or systemic embolism in patients with atrial fibrillation. OBJECTIVE: To determine the efficacy and safety of rivaroxaban compared with warfarin among vitamin K antagonist (VKA)-naive and VKA-experienced patients. DESIGN: Prespecified subgroup analysis. (ClinicalTrials.gov: NCT00403767). SETTING: Global. PATIENTS: 14,264 persons with atrial fibrillation. MEASUREMENTS: Interaction of the relative treatment effect of rivaroxaban and warfarin on stroke or systemic embolism among VKA-naive and VKA-experienced patients. RESULTS: Overall, 7897 (55.4%) patients were VKA-experienced and 6367 (44.6%) were VKA-naive. The effect of rivaroxaban versus warfarin on stroke or systemic embolism was consistent: Rates per 100 patient-years of follow-up were 2.32 versus 2.87 for VKA-naive patients (hazard ratio HR, 0.81 95% CI, 0.64 to 1.03) and 1.98 versus 2.09 for VKA-experienced patients (HR, 0.94 CI, 0.75 to 1.18; interaction P = 0.36). During the first 7 days, rivaroxaban was associated with more bleeding than warfarin (HR in VKA-naive patients, 5.83 CI, 3.25 to 10.44, and in VKA-experienced patients, 6.66 CI, 3.83 to 11.58; interaction P = 0.53). After 30 days, rivaroxaban was associated with less bleeding than warfarin in VKA-naive patients (HR, 0.84 CI, 0.74 to 0.95) and similar bleeding in VKA-experienced patients (HR, 1.06 CI, 0.96 to 1.17; interaction P = 0.003). LIMITATION: The trial was not designed to detect differences in these subgroups. CONCLUSION: The efficacy of rivaroxaban in VKA-experienced and VKA-naive patients was similar to that of the overall trial. There were more bleeding events within 7 days of study drug initiation with rivaroxaban, but after 30 days, rivaroxaban was associated with less bleeding in VKA-naive patients and similar bleeding in VKA-experienced patients. This information may be useful to clinicians considering a transition to rivaroxaban for patients receiving VKA therapy. PRIMARY FUNDING SOURCE: Johnson & Johnson and Bayer HealthCare.