Multicenter Trial of Rivaroxaban for Early Discharge of Pulmonary Embolism From the Emergency Department (MERCURY PE): Rationale and Design.

OBJECTIVES

Traditionally, patients with pulmonary embolism (PE) are admitted from the emergency department and treated with low-molecular-weight heparin followed by warfarin. Several studies now demonstrate that it is possible to identify low-risk PE patients that can safely be treated as outpatients. The advent of the direct-acting oral anticoagulants such as rivaroxaban has made it easier than ever to manage patients outside of the hospital. This article describes the design of a randomized controlled trial aimed at testing the hypothesis that low-risk PE patients can be safely and effectively managed at home using rivaroxaban, resulting in fewer days of hospitalization than standard-of-care treatment.

METHODS

We have initiated a multicenter, open-label, randomized clinical trial in which low-risk adult PE patients (identified by the Hestia criteria) are randomized to outpatient management with oral rivaroxaban 15 mg twice daily for 21 days followed by 20 mg once daily for 90 days versus standard care, determined by the treating physician and based on local practices. The primary clinical endpoint will be the total number of inpatient hospital days (including the index admission) for venous thromboembolic or bleeding-related events during the first 30 days after randomization. A total of 150 subjects per group will provide 82% power to detect a difference of 1 day or greater in the primary outcome.

RESULTS

Patient enrollment is ongoing at present in 45 of 60 planned sites. No interim analysis is planned and the study is being monitored by a data safety management board.

CONCLUSIONS

The MERCURY PE study is designed to test the hypothesis that outpatient management of low-risk PE patients with rivaroxaban reduces the number of hospitalization days from venous thromboembolism and bleeding compared with standard care. This article describes the rationale and methodology for this study.