Clinical Trial: Dabigatran Treatment Following Transient Ischemic Attack and Minor Stroke

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Dabigatran Treatment Following Transient Ischemic Attack and Minor Stroke

Brief Summary:

Objective: Demonstrate the safety of early use of dabigatran following TIA/minor stroke.

Background: Although aggressive antithrombotic therapy has been shown to reduce the number of new ischemic events following stroke/TIA, this has always been offset by an increase in the risk of hemorrhagic transformation. Dabigatran is much safer than previously tested antithrombotic agents, with respect to intracranial bleeding and therefore offers a unique treatment opportunity in these high-risk patients. TIA/minor stroke represent the largest group of cerebrovascular disease patients. A short-term intervention such as 30 days of dabigatran treatment has the potential for a very large impact from the population health perspective, given the number of patients who may be treated if a benefit can be demonstrated.

Study design:

This is an open label, single arm study. Patients with TIA/minor stroke (National Institutes of Health Stroke Scale (NIHSS) score </=3) who can be treated within 24 hours of symptom onset will be eligible. All patients will be treated with dabigatran for 30 days. The dose of dabigatran will be determined by age and renal function (patients >80 years old and/or with GFR 30-50 ml/min will received 110 mg bid, and all other patients will receive 150 mg BID).The primary endpoint is symptomatic hemorrhagic transformation. Patients (n=50) with TIA/minor stroke, defined as having a National Institutes of Health Stroke Scale Score of </=3, will undergo an MRI, including diffusion-weighted imaging (DWI), as well as gradient recall echo (GRE) sequences, which will be used to assess for hemorrhagic transformation. Patients will have a repeat MRI examination at 7 and 30 days to assess for hemorrhagic transformation and new lesion development. The primary endpoint of

Detailed Summary:

Background: A transient ischemic attack (TIA) has traditionally been defined as a focal neurologic deficit lasting less than 24 hours, but alternative definitions based on tissue injury have been more recently proposed.1 This clinical definition has been based on the assumption that TIAs are associated with complete resolution of brain ischemia occurring rapidly enough to cause only transient symptoms and no permanent brain injury, i.e. stroke. A recently completed MRI research study at the University of Alberta indicates that TIA and minor stroke actually represent a continuum of symptoms secondary to brain ischemia.2 There is also substantial evidence that the period shortly after a TIA or minor stroke is one of elevated recurrent stroke risk; as high as 17% at 3 months.3, 4 We have previously reported that MRI markers of new infarction are actually present within 7 days of the index event in 18% of patients.2 TIA and minor stroke can therefore be seen as a sentinel warning for impending major stroke, which offers a potential window for therapeutic intervention. Given the large number of patients who suffer a TIA/minor stroke, it is important to identify and target those patients at highest risk for early recurrence.

Treatment of Minor Stroke/TIA: A logical approach to prevent early recurrence is aggressive hyperacute antithrombotic therapy following TIA/minor stroke, as is now the standard of care in acute coronary syndrome management. This treatment strategy is aimed at preventing both recurrent thromboembolism and propagation of existing thrombi. In acute coronary syndrome patients, antithrombotic therapy consists of both anticoagulants (low molecular weight heparin) and combination antiplatelet agents (ASA+high dose clopidogrel, or more recently prasugrel/ticagrelor). In ischemic stroke patients the benefits of traditional anticoagulants, particularly heparin, have
Sponsor: University of Alberta

Current Primary Outcome: Symptomatic Hemorrhagic Transformation [ Time Frame: 30 days post-treatment ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: University of Alberta

Dates:
Date Received: February 24, 2012
Date Started: February 2012
Date Completion:
Last Updated: October 29, 2014
Last Verified: October 2014