It is well known that Coumadin is effective in preventing stroke in patients with atrial fibrillation. But Coumadin (warfarin) is not so easy to use. Dosage is highly variable between patients, diet may affect therapeutic levels, and frequent blood tests are required to keep patients in the correct range of anticoagulation. Now a new class of drugs is emerging which may be useful for preventing stroke.
At the European Society Cardiology meeting in Stockholm this week, a study known as AVERROES was presented. This study used a drug known as apixaban (Pfizer / Bristol-Myers Squibb) compared to aspirin in patients with atrial fibrillation. Patients treated with apixaban had a significantly lower percentage of stroke, without significant increased bleeding.
The newer drugs do not require any monitoring via blood testing, and appear to be effective. Although side effects appear to be minimal, some may become apparent with more widespread use. Apixaban will require twice daily dosing, which may be inconvenient for some patients. A study directly comparing apixaban to warfarin will be completed sometime in 2011.
These drugs usher in a new era in stroke prevention for patients with atrial fibrillation. The first of these drugs may become available in 2011.