Blood thinner Eliquis (apixaban), developed by Pfizer and Bristol-Myers Squibb (BMS), has shown positive data in a phase III trial comparing it to standard anticoagulant warfarin.
The ARISTOTLE trial, which involved 18,201 patients with atrial fibrillation and at least one risk factor for stroke, demonstrated a 21 per cent reduced risk of stroke or systemic embolism for patients taking Eliquis compared to warfarin.
There was also a reduced risk in major bleeding by 31 per cent and mortality by 11 per cent.
Dr Christopher B Granger, the lead investigator for the trial, described the risk of stroke in patients with atrial fibrilliation as a "major public health concern" and said that Eliquis showed significant improvement over warfarin in reducing related risks.
The results were presented at the European Society of Cardiology Congress 2011 in Paris and are published in the New England Journal of Medicine.
In November 2010, Pfizer and BMS had to call halt to a large phase III trial of apixaban as a treatment for acute coronary syndrome due to an increase in bleeding observed in subjects receiving the therapy.
BMS discovered apixaban and is co-developing and potentially commercialising the drug under a 2007 partnership with Pfizer.