The purpose of this study is to evaluate the safety and efficacy of two doses of TB-402 administered as a single intravenous infusion for the prevention of VTE in subjects undergoing total hip replacement surgery.

Inclusion Criteria:

1. Male or female subjects aged ≥ 18 years.
2. Written informed consent.
3. Willing and able to comply with scheduled visits, treatment plan, laboratory tests and other study procedures

Exclusion Criteria:

1. Pregnancy at the time of screening.
2. Indication for anticoagulation other than post-operative thromboprophylaxis.
3. Active bleeding or high risk of bleeding.
4. Anticipated continued use of neuraxial catheter after surgery.
5. Clinical laboratory findings at screening of thrombocytopenia or prolonged aPTT or PT.
6. Uncontrolled hypertension.
7. Impaired liver function (transaminase >3 X ULN) or history of hepatic insufficiency.
8. Creatinine clearance <30 mL/min.
9. Antiplatelet agents other than low dose aspirin (< 200mg).
10. The use of intermittent pneumatic compression.
11. Known hypersensitivity to contrast media or rivaroxaban.
12. Known drug or alcohol abuse.
13. Active malignant disease or current cytostatic treatment.
14. Stroke within the previous month.
15. Participation in an investigational drug study within the past 30 days or previous participation in this study.
16. Any condition that in the opinion of the investigator would put the subject at increased risk from participating in the study or expected inability to comply with the protocol.