Title

Factor Xa Inhibitor, PRT054021, Against Enoxaparin for the Prevention of Venous Thromboembolic Events (EXPERT)
Evaluation of the Factor Xa Inhibitor, PRT054021, Against Enoxaparin in a Randomized Trial for the Prevention of Venous Thromboembolic Events After Unilateral Total Knee Replacement (EXPERT)
  • Phase

    Phase 2
  • Study Type

    Interventional
  • Intervention/Treatment

    betrixaban ...
  • Study Participants

    215
Randomized study of PRT054021 40 mg and 15 mg bid vs. enoxaparin 30 mg q12h for the prophylaxis of venous thromboembolic events after unilateral knee replacement surgery.
Approximately 200 patients undergoing unilateral knee replacement will be entered into the study and randomized to receive either enoxaparin 30 mg sq bid, PRT054021 15 mg po bid, or PRT054021 40 mg po bid for 10 to 14 days, at which time patients will undergo venography.
Study Started
May 31
2006
Primary Completion
Jan 31
2007
Study Completion
Feb 28
2007
Results Posted
Dec 15
2017
Last Update
Aug 07
2023

Drug Betrixaban

Capsule

Drug Enoxaparin

Administered subcutaneously

  • Other names: Lovenox

Betrixaban 15 mg Experimental

Betrixaban 15 mg oral twice daily for 10 to 14 days

Betrixaban 40 mg Experimental

Betrixaban 40 mg oral twice daily for 10 to 14 days

Enoxaparin Experimental

Enoxaparin 30 mg administered subcutaneously every 12 hours for 10 to 14 days

Criteria

Inclusion Criteria:

• The subject has undergone elective primary unilateral TKR (not unicompartmental).

Demographic

The subject is between the ages of 18 and 75 years.
If the subject is a woman, she is without reproductive potential (postmenopausal for >2 years or after hysterectomy).
The subject weighs between 50 kg (110 lbs) and 120 kg (265 lbs). Laboratory and Procedures
The subject is willing and able to undergo unilateral venography. Medications
The subject is willing and able to self-inject enoxaparin or receive injections q12h by a caregiver.

Ethical • The subject is able to read and give written informed consent and has signed an informed consent form approved by the Investigator's IRB/IEC.

Exclusion Criteria:

Disease Related

Major medical and/or surgical condition which may impair oral drug absorption or metabolism.
Immobilization for 3 or more days before surgery.
History (including family history) or symptoms of a congenital or acquired bleeding disorder or vascular malformation; or a history of intracranial, retroperitoneal, or intraocular bleeding within the last 6 months; or is felt to be at high risk for bleeding for other reasons.
Gastrointestinal bleeding within 90 days before surgery or endoscopically verified ulcer disease within 30 days before surgery.
Indwelling intrathecal or epidural catheter during the prophylaxis period (except for epidural catheter if removed after surgery); or unusual difficulty in administering spinal or epidural anesthesia (eg, 3 or more attempts, "traumatic taps").
Major surgery, ischemic stroke, or myocardial infarction within 3 months before Screening.
Uncontrolled hypertension defined as systolic blood pressure (SBP) > 180 mmHg or diastolic blood pressure (DBP) >105 mmHg.
Hypotension defined as SBP <95 mmHg.
Evidence at Screening of symptomatic congestive heart failure requiring treatment.
Chronic atrial fibrillation treated with oral anticoagulants, recurrent atrial arrhythmia(s) or a history of recurrent ventricular tachycardia.

Laboratory and Procedures

• Evidence at Screening of: platelet count <100,000/mm3 potassium <3.5 mEq/L hemoglobin concentration <10 g/dL or hematocrit <30% serum ALT or AST >2 times ULN serum creatinine >2.0 mg/dL (180 µm/L)

Contraindication to venography, including to iodinated contrast medium
QTc on Screening ECG >450 msec and/or a personal or family history of "Long QT Syndrome".

Medications

Contraindication to anticoagulation for VTE prophylaxis, including a contraindication to receiving heparin or heparinoids.
Administration of the following drugs within 7 days before TKR: thrombolytic agents, anticoagulants and/or anti-platelet agents (eg, heparins, warfarin, dipyridamole, sulfinpyrazone, ticlopidine, dextran, clopidogrel). Aspirin up to 325 mg once daily and NSAIDs are allowed but discouraged.
Use of class III antiarrhythmics drugs (eg, dofetilide, ibutilide, amiodarone, bretylium, sotalol) within 30 days prior to TKR.

General

Participation in any investigational drug study 30 days prior to enrollment is prohibited. Participation in a device trial prior to enrollment is acceptable.
Any condition which could interfere with or for which the treatment of might interfere with the conduct of the study, or which would, in the opinion of the Investigator, unacceptably increase the risk of the subject's participation in the study. This would include, but is not limited to alcoholism, drug dependency or abuse, psychiatric disease, epilepsy or any unexplained blackouts.

Summary

Betrixaban 15 mg

Betrixaban 40 mg

Enoxaparin

All Events

Event Type Organ System Event Term Betrixaban 15 mg Betrixaban 40 mg Enoxaparin

Incidence of Adjudicated Venous Thromboembolism (VTE)

Incidence of adjudicated venous thromboembolism (VTE) through Day 10-14 following TKR where VTE is defined as DVT (proximal and/or distal) and/or PE. Patients were evaluated for VTE daily while hospitalized and were contacted every 2 to 4 days after discharge and before the day of the mandatory venogram to monitor for study endpoints

Betrixaban 15 mg

20.0
Percentage of Participants
95% Confidence Interval: 11.4 to 31.3

Betrixaban 40 mg

15.4
Percentage of Participants
95% Confidence Interval: 7.6 to 26.5

Enoxaparin

10.0
Percentage of Participants
95% Confidence Interval: 2.8 to 23.7

Incidence of Adjudicated Overt Bleeding Events: Primary Safety Endpoint

The incidence of adjudicated major and clinical relevant non-major bleeding. Major bleeding was defined as fatal, involving vital organs, requiring additional surgery or a new therapeutic procedure, or a bleeding index >=2. Bleeding Index was defined as the number of units of packed red blood cells or whole blood transfused plus the haemoglobin values before the bleeding episode minus the haemoglobin values after the bleed had stabilized (in g/dL)

Betrixaban 15 mg

Betrixaban 40 mg

2.4
Percentage of Participants
95% Confidence Interval: 0.3 to 8.3

Enoxaparin

7.0
Percentage of Participants
95% Confidence Interval: 1.5 to 19.1

Incidence of Adjudicated Pulmonary Embolism (PE) and All Deep Vein Thrombosis (DVT) (Proximal and Distal)

Incidence of adjudicated pulmonary embolism (PE) and all deep vein thrombosis (DVT) (proximal and distal) through the time of venography on Day 10 to 14 and at follow-up at approximately 6 (±2) weeks after TKR surgery

Betrixaban 15 mg

20.0
Percentage of Participants
95% Confidence Interval: 11.4 to 31.3

Betrixaban 40 mg

15.4
Percentage of Participants
95% Confidence Interval: 7.6 to 26.5

Enoxaparin

12.5
Percentage of Participants
95% Confidence Interval: 4.2 to 26.8

Total

214
Participants

Age, Continuous

63.7
years (Mean)
Standard Deviation: 8.1

Sex: Female, Male

Overall Study

Betrixaban 15 mg

Betrixaban 40 mg

Enoxaparin

Drop/Withdrawal Reasons

Betrixaban 15 mg

Betrixaban 40 mg

Enoxaparin