American Society of Hirudotherapy

Dabigatran or warfarin for the prevention of stroke in atrial fibrillation? A closer look at the RE-LY trial.

Review published in Expert opinion on pharmacotherapy (2012)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewClinical TrialsDrug DevelopmentDiNicolantonio · Expert opinion on pharmacotherapy, 2012

Abstract

INTRODUCTION: In the Randomized Evaluation of Long-term Anticoagulant Therapy (RE-LY) trial, dabigatran 150 mg was shown to be superior to warfarin for the prevention of stroke or systemic embolism. However, there are some concerns with the RE-LY trial, such as its open-label design, potential unblinding of "blinded" adjudicators, the use of concomitant warfarin-aspirin (ASA), the disparity between baseline use of nonselective NSAIDs; the high unequal rate of drop-outs; unaccounted drop-ins; high rates of major bleeds in warfarin-treated patients, despite being a low risk population; and rates of major bleeds that do not match historic warfarin trials. Furthermore, although dabigatran offers potential advantages versus warfarin, there are disadvantages that must be taken into consideration before a patient is switched from the latter to the former. This review will summarize the flaws of the RE-LY trial as well as the clinically important advantages and disadvantages of dabigatran and warfarin. AREAS COVERED: This review examines the differences between dabigatran and warfarin in terms of side effects, drug-drug interactions, drug-food interactions, and potential reasons for using one anticoagulant rather than the other. The main focus of this review is a discussion of the design, procedures and results of the RE-LY trial. EXPERT OPINION: There seem to be major flaws with the RE-LY trial. A double-blinded trial should be performed testing dabigatran against warfarin to verify the results of the RE-LY trial.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleReview
Indexed MeSH termsAnticoagulantsAtrial FibrillationBenzimidazolesDabigatranDrug InteractionsHumansStrokeWarfarinbeta-Alanine

Summary

In the Randomized Evaluation of Long-term Anticoagulant Therapy (RE-LY) trial, dabigatran 150 mg was shown to be superior to warfarin for the prevention of stroke or systemic embolism. However, there are some concerns with the RE-LY trial, such as its open-label design, potential unblinding of...

Why This Matters for Hirudotherapy

This review critically appraised the RE-LY trial comparing dabigatran to warfarin for prevention of stroke or systemic embolism, citing design concerns including its open-label design, potential unblinding of adjudicators, high drop-out rates, and bleeding-rate discrepancies, while also discussing clinically important advantages and disadvantages of both anticoagulants. The abstract makes no mention of leeches, hirudin, hirudotherapy, or any pharmacological relationship to the leech anticoagulant secretome. No defensible leech link can be established from its content. Caveat: the article is a review with expert opinion advocating for a double-blinded trial; its relevance to ASH's domain is nil.

Citation

Dabigatran or warfarin for the prevention of stroke in atrial fibrillation? A closer look at the RE-LY trial.

DiNicolantonio · Expert opinion on pharmacotherapy, 2012

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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