The purpose of this study is to examine the superiority of YM150 to the placebo and to evaluate the dose-dependent response of YM150 in patients undergoing elective total knee replacement surgery.

Inclusion Criteria:

• Subjects is scheduled for elective primary total knee replacement surgery
• Written informed consent obtained before screening

Exclusion Criteria:

• Subject has history of deep vein thrombosis and/or pulmonary embolism
• Subject has a hemorrhagic disorder and/or coagulation disorder
• Subject has had clinically important bleeding occurred within 90 days prior to the screening visit
• Subject has an acute bacterial endocarditis, retinopathy, hypertension, or thrombocytopenia
• Subject is receiving anticoagulants/antiplatelets