American Society of Hirudotherapy

Efficacy and Safety of Reteplase Versus Alteplase in Acute Ischemic Stroke Based on Fibrinogen Levels: The RAISE Trial Subgroup

Research article published in Journal of the American Heart Association (2026)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Randomized controlled trialSafety & Infection ControlWang et al. · Journal of the American Heart Association, 2026

Abstract

BACKGROUND: The effects of intravenous thrombolytic agents on fibrinogen differ due to structural differences among the agents. Using data from the RAISE (Reteplase Versus Alteplase for Acute Ischemic Stroke) trial, we aimed to investigate the impact of differences in baseline plasma fibrinogen levels on the efficacy and safety of reteplase versus alteplase within 4.5 hours of acute ischemic stroke symptom onset. METHODS: This post hoc subgroup analysis of the multicenter RAISE trial categorized participants by baseline fibrinogen levels: low (<2 g/L), normal (2-4 g/L), and high (>4 g/L). The primary efficacy outcome was excellent functional outcome at 90 days (modified Rankin scale score of 0 or 1). The primary safety outcome was symptomatic intracranial hemorrhage within 36 hours. RESULTS: A total of 1373 patients with acute ischemic stroke were included. Ninety-two in the low fibrinogen group (<2 g/L), 1178 in the normal fibrinogen group (2-4 g/L), and 103 in the high fibrinogen group (>4 g/L). Adjusted risk ratios of primary efficacy outcome were 1.13 (95% CI, 0.97-1.32) for the low fibrinogen group, 1.13 (95% CI, 1.04-1.23) for the normal fibrinogen group, and 1.09 (95% CI, 0.84-1.42) for the high fibrinogen group. The primary safety outcome showed no difference between reteplase and alteplase in the 3 fibrinogen subgroups. CONCLUSIONS: Among patients with acute ischemic stroke who were treated with either reteplase or alteplase within 4.5 hours after symptom onset, there was no difference observed in the relative efficacy and safety between the 2 groups across the 3 fibrinogen subgroups. However, these findings should be interpreted cautiously and require validation in larger, adequately powered prospective studies. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05295173.

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

Publication typeJournal ArticleMulticenter StudyRandomized Controlled TrialComparative Study
Indexed MeSH termsHumansMaleTissue Plasminogen ActivatorFemaleFibrinogenFibrinolytic AgentsIschemic StrokeAgedMiddle AgedTreatment OutcomeRecombinant ProteinsThrombolytic Therapy

Summary

Peer-reviewed research on safety and infection-control considerations relevant to leech therapy and anticoagulation. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This post hoc subgroup analysis of the randomized RAISE trial (1,373 acute ischemic stroke patients treated within 4.5 hours) tested whether baseline plasma fibrinogen level changes the relative efficacy and safety of reteplase versus alteplase, and found no difference in excellent 90-day functional outcome or symptomatic intracranial hemorrhage across low, normal, and high fibrinogen subgroups. Its relevance to ASH is indirect but instructive: it shows how a coagulation-cascade biomarker (fibrinogen) is used to stratify thrombolytic response, illustrating the kind of mechanistic, biomarker-guided thinking that also underlies interest in the medicinal-leech secretome's anti-thrombotic enzymes. The honest caveat is that this is a secondary subgroup analysis (the authors themselves note it needs validation in larger powered trials), it concerns recombinant plasminogen activators rather than any leech-derived agent, and it bears no direct connection to hirudotherapy.

Citation

Efficacy and Safety of Reteplase Versus Alteplase in Acute Ischemic Stroke Based on Fibrinogen Levels: The RAISE Trial Subgroup.

Wang et al. · Journal of the American Heart Association, 2026

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

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