Design of Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate vs. Acetylsalicylic Acid in Patients with Embolic Stroke of Undetermined Source (Re-Spect Esus)

Abstract

Rationale Cryptogenic ischemic strokes constitute 20–30% of ischemic strokes, the majority of which are embolic strokes of undetermined source. The standard preventive treatment in these patients is usually acetylsalicylic acid. Aim The Randomized, double-blind, Evaluation in secondary Stroke Prevention comparing the EfficaCy and safety of the oral Thrombin inhibitor dabigatran etexilate vs. acetylsalicylic acid in patients with Embolic Stroke of Undetermined Source (RE-SPECT ESUS) is designed to determine whether the oral thrombin inhibitor dabigatran, taken within three-months after embolic stroke of undetermined source, is superior to acetylsalicylic acid for prevention of recurrent stroke and to characterize the safety of dabigatran in this setting. Design Prospective, randomized, double-blind, multicenter trial in approximately 6000 patients and 550 centers with embolic stroke of undetermined source. Subjects are randomized to dabigatran or acetylsalicylic acid and treated for an expected minimum of six-months and up to approximately three-years. It is an event-driven trial aiming for 353 adjudicated primary outcome events. Study outcomes The primary efficacy outcome is time to first recurrent stroke (ischemic, hemorrhagic, or unspecified). Key secondary outcomes are time to first ischemic stroke and time to first occurrence in the composite outcome of nonfatal stroke, nonfatal myocardial infarction, and cardiovascular death. The primary safety outcome is major hemorrhage, including symptomatic intracranial hemorrhage. Discussion Acetylsalicylic acid is the most common antithrombotic given to patients with embolic strokes of undetermined source to reduce recurrence risk. This trial will determine whether anticoagulation with dabigatran is more effective than acetylsalicylic acid, and acceptably safe.