Article

The Argatroban and Tissue-Type Plasminogen Activator Stroke Study Final Results of a Pilot Safety Study

Department of Neurology, University of Texas–Houston Medical School, Houston, TX, USA.
Stroke (Impact Factor: 5.72). 03/2012; 43(3):770-5. DOI: 10.1161/STROKEAHA.111.625574
Source: PubMed

ABSTRACT

Argatroban is a direct thrombin inhibitor that safely augments recanalization achieved by tissue-type plasminogen activator (tPA) in animal stroke models. The Argatroban tPA Stroke Study was an open-label, pilot safety study of tPA plus Argatroban in patients with ischemic stroke due to proximal intracranial occlusion.
During standard-dose intravenous tPA, a 100-μg/kg bolus of Argatroban and infusion for 48 hours was adjusted to a target partial thromboplastin time of 1.75× baseline. The primary outcome was incidence of significant intracerebral hemorrhage defined as either symptomatic intracerebral hemorrhage or Parenchymal Hematoma Type 2. Recanalization was measured at 2 and 24 hours by transcranial Doppler or CT angiography.
Sixty-five patients were enrolled (45% men, mean age 63±14 years, median National Institutes of Health Stroke Scale=13). The median (interquartile range) time tPA to Argatroban bolus was 51 (38-60) minutes. Target anticoagulation was reached at a median (interquartile range) of 3 (2-7) hours. Significant intracerebral hemorrhage occurred in 4 patients (6.2%; 95% CI, 1.7-15.0). Of these, 3 were symptomatic (4.6%; 95% CI, 0.9-12.9). Seven patients (10%) died in the first 7 days. Within the 2-hour monitoring period, transcranial Doppler recanalization (n=47) occurred in 29 (61%) patients: complete in 19 (40%) and partial in another 10 (21%).
The combination of Argatroban and intravenous tPA is potentially safe in patients with moderate neurological deficits due to proximal intracranial arterial occlusions and may produce more complete recanalization than tPA alone. Continued evaluation of this treatment combination is warranted.
URL: www.clinicaltrials.gov. Unique identifier: NCT00268762.

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    • "The association of thrombin activity with neuronal damage and long-term cognitive deficit may be clinically significant and suggests a role for early thrombin inhibitor therapy for stroke patients. A pilot trial of argatroban has been completed and further trials are planned (Sugg et al., 2006; Barreto et al., 2012). However, current clinical trials are designed using argatroban for its anti-thrombotic property and the dose is adjusted to elevate activated partial thromboplastin time. "
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