Trends say that India will report 1.6 million cases of stroke annually by 2015. Atrial fibrillation is a common heart rhythm disorder that increases the risk of stroke.
A new experimental anti-clotting drug called Apixaban has been found to be efficient in reducing the risk of stroke in these patients. It was found to be far superior to aspirin.
AdvertisementThe condition is typically treated by using a type of anticoagulant known as a Vitamin K antagonist. Warfarin is the most common vitamin K antagonist. A patient on vitamin K antagonists requires serious monitoring owing to a marked variation in its effect both from one patient to another and within the individual patient. Its use is further limited by a narrow therapeutic window, i.e. doses have to be precisely titered so as to avoid danger of bleeding and not all patients are suitable for vitamin K antagonist therapy. The use of vitamin K antagonists is generally difficult. Aspirin continues to be used in treating patients with atrial fibrillation for whom vitamin K antagonist therapy is unsuitable but it is less effective. The search for better drugs has been a challenge but a recent trial called the AVERROES study tested the effect of Apixaban and this brings some promise.
Apixaban is a drug that inhibits one of the components that take part in the body's clotting mechanism (called factor Xa). At a dose of 2.5 mg twice daily, Apixaban, an anti-thrombotic drug to be precise, was known to be effective and safe for the prevention of venous thromboembolism after elective orthopedic surgery. The AVERROES study conducted at 522 centers in 36 countries evaluated the efficacy and safety of apixaban, at a dose of 5 mg twice daily, as compared with aspirin, at a dose of 81 to 324 mg daily, for the treatment of patients with atrial fibrillation for whom vitamin K antagonist therapy was considered unsuitable. The results were published in the New England Journal of Medicine (NEJM).
'In patients for whom vitamin K antagonist therapy was considered unsuitable, apixaban, as compared with aspirin, reduced the risk of stroke or systemic embolism by more than 50%, without a significant increase in the risk of major bleeding', reported NEJM. Apixaban did not bring any significant increase in the risk of major bleeding such as intracranial bleeding. Apixaban and was found to be superior to aspirin.
If approved, Apixaban will offer an effective alternative to warfarin, whose limitations have already been discussed. The approval of the drug will bring a revolutionary change in medical practice.
Source: New England Journal of Medicine