Bristol-Myers Squibb and Pfizer reported that an interim analysis of results from a Phase III study of apixaban for the prevention of venous thromboembolism (VTE) in patients undergoing knee replacement indicate that the primary endpoint of this study was not met.     The Phase III VTE prevention study known as ADVANCE-1 compared apixaban, an oral Factor Xa inhibitor given at a dose of 2.5 mg, twice daily, to the FDA-approved dose of Sanofi-Aventis’ enoxaparin, 30 mg given twice daily....