Hello, my name is Dr. Mark Alberts, Professor of Neurology and Director of the Stroke Program at Northwestern University in Chicago. Thank you for joining me for this Medscape stroke update. Today we have some very exciting news. Just a few days ago, the FDA approved dabigatran, which is a direct thrombin inhibitor, as the first new agent to prevent stroke and systemic emboli in patients with nonvalvular atrial fibrillation (AF). This represents a tremendous advance because you don't need to do routine INR [international normalized ratio] monitoring with dabigatran, and there are few, if any, food and drug interactions.
The FDA approved a dose of dabigatran of 150 mg twice a day for use in patients with nonvalvular AF. In the pivotal RE-LY (Randomized Evaluation of Long-term Anticoagulant Therapy) study, this dose was found to be superior to warfarin for the prevention of stroke and systemic emboli.
There are a few questions about the use of dabigatran in patients with a recent stroke due to nonvalvular AF. How soon can we begin dabigatran in those patients? According to the RE-LY study, patients had to be at least 14 days beyond the onset of their stroke. In other studies of direct thrombin inhibitors, you had to wait for 30 days. At least 2 weeks seems to be what is recommended at this point. Obviously, we need to use our clinical judgment to weigh and balance the risk for bleeding with this new agent in a setting of an acute stroke, vs the risk for having another ischemic stroke in someone with AF.
Another question is, what do we do if there are bleeding complications while patients are taking dabigatran? The good thing is that the anticoagulation effect tends to reverse within hours after stopping the medication, but if there is an emergency situation and we need to rapidly reverse the effects of the drug, what can we do? Some coagulation experts suggest that the infusion of PCC (protein complex concentrate) can be effective in reducing the anticoagulation effect. Perhaps the one best agent of this type would be FEIBA [factor eight inhibitor bypass activity], which is made by Baxter. This is a very potent PCC combination that has activated clotting factors, so this may be one thing to consider, but clearly there is a paucity of clinical data about how to best do this.
When will dabigatran be available? What we hear is that it will be in your local pharmacies within a matter of days, so you can begin using it in your patients with nonvalvular AF. A brief word of caution, however: Dabigatran is a powerful anticoagulant, and if someone is taking it and has an ischemic stroke, you probably should not treat them with TPA [tissue plasminogen activator] at the same time because that could increase the risk for bleeding complications. Again, we don't have a lot of data about this combination.
Dabigatran is a very exciting new agent with significant advantages over warfarin. Hopefully this will help you and your colleagues treat more high-risk patients with dabigatran who are in AF and at high risk for having a stroke, because it appears that it's going to be a lot easier and safer to do than using standard warfarin therapy. Thank you very much for joining me for this Medscape stroke update.
Medscape Neurology © 2010
Cite this: Mark J. Alberts. Dabigatran Approved! Now How Do We Use It? - Medscape - Nov 11, 2010.