Comparing Enoxaparin to Fondaparinux to Prevent Venous Thromboembolism (VTE) in Bariatric Surgical Patients

A Pilot Study to Determine the Feasibility of Conducting a Randomized Clinical Trial Comparing Fondaparinux Sodium (Arixtra) Once Daily With Enoxaparin (Lovenox®) Twice Daily With Respect to Preventing VTE After Bariatric Surgery in Obese Patients

This pilot study is designed to determine the feasibility of conducting a randomized clinical trial comparing fondaparinux sodium (Arixtra) once daily with enoxaparin (Lovenox®) twice daily with respect to preventing deep vein thrombosis (DVT) and pulmonary embolism (PE) after bariatric surgery in obese patients.

Study Overview

• Status: Completed
• Conditions: Pulmonary Embolism; Deep Venous Thrombosis
• Intervention / Treatment: Drug: Enoxaparin; Drug: Fondaparinux

Detailed Description

In order to determine the feasibility of such a trial we need to determine the necessary sample size. In order to determine the necessary sample size, we need to obtain estimates of the incidence of DVT and the prevalence of PE using MRV in each treatment group. Descriptive statistics and 95% confidence intervals will be calculated to determine the incidence of DVT and the prevalence of PE using MRV in obese patients who have received treatment to prevent DVT and PE associated with bariatric surgery.

Anti-factor Xa levels will be used to help determine if treatments are reaching appropriate levels.

• Study Type: Interventional
• Enrollment (Actual): 198
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Baltimore, Maryland, United States, 21224
      • Johns Hopkins Bayview Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Men or women 18 years or older.
2. Body mass index (BMI) of 35kg/m2 or greater.
3. Undergoing laparoscopic bariatric surgery, i.e., laparoscopic sleeve gastrectomy, laparoscopic Roux-en Y gastric bypass or laparoscopic duodenal switch.

Exclusion Criteria:

1. History of previous deep vein thrombosis.
2. History of previous pulmonary emboli.
3. History of documented clotting/coagulation disorder.
4. History of cancer.
5. Weight < 50 kg or > 200 kg or unable to fit in MRI scanner.
6. Presence of metallic foreign bodies
7. Recent history of smoking (within the last year).
8. History of venous stasis disease.
9. History of obesity hypoventilation syndrome.
10. Patients who are unable to lay flat for extended periods of time or are claustrophobic.
11. Patients who have a pacemaker, an implanted defibrillator or certain other implanted or electronic or metallic devices (implanted medical or metallic devices, shrapnel, or metal).
12. History of hypersensitivity reaction to anticoagulation products.
13. History of HIT (Heparin Induced Thrombocytopenia.
14. History of Renal Insufficiency (Creatinine Clearance < 50).
15. Active clinically significant bleeding.
16. Acute bacterial endocarditis.
17. BMI > 60.
18. Patients with metallic foreign body or implant (unable to have an MRV study).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Enoxaparin; Patients will receive enoxaparin 40mg subcutaneously twice daily during perioperative period of bariatric surgery. Patients will be encouraged to ambulate and compression stockings while in bed.	Drug: Enoxaparin; Patients will receive enoxaparin 40mg subcutaneously twice daily during perioperative period of bariatric surgery. Patients will be encouraged to ambulate and compression stockings while in bed.
Active Comparator: Fondaparinux; Fondaparinux 5mg subcutaneously 6 hours following surgery, fondaparinux 5mg subcutaneously once daily during hospitalization. Patients will be encouraged to ambulate and compression stockings while in bed.	Drug: Fondaparinux; Fondaparinux 5mg subcutaneously 6 hours following surgery, fondaparinux 5mg subcutaneously once daily during hospitalization. Patients will be encouraged to ambulate and compression stockings while in bed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
To estimate the prevalence of asymptomatic deep venous thrombosis and pulmonary emboli in obese patients undergoing bariatric surgery.	2 years

Secondary Outcome Measures

Outcome Measure	Time Frame
To assess the relationship of Anti-factor Xa levels and the occurrence of deep venous thrombosis and pulmonary emboli in bariatric patients receiving standard dose of anticoagulation (enoxaparin/Lovenox or fondaparinux/Arixtra).	2 years

Collaborators and Investigators

• Sponsor: Johns Hopkins University
• Collaborators: GlaxoSmithKline
• Investigators: Principal Investigator: Kimberley E Steele, MD, Johns Hopkins University

Study record dates

Study Major Dates

• Study Start: June 1, 2009
• Primary Completion (Actual): September 1, 2013
• Study Completion (Actual): September 1, 2013

Study Registration Dates

• First Submitted: May 5, 2009
• First Submitted That Met QC Criteria: May 5, 2009
• First Posted (Estimate): May 6, 2009

Study Record Updates

• Last Update Posted (Actual): June 7, 2019
• Last Update Submitted That Met QC Criteria: June 5, 2019
• Last Verified: June 1, 2019

More Information

Terms related to this study

• Keywords: bariatric surgery; PE; DVT; MRV
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Respiratory Tract Diseases; Lung Diseases; Embolism and Thrombosis; Embolism; Thrombosis; Venous Thrombosis; Pulmonary Embolism; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Fibrinolytic Agents; Fibrin Modulating Agents; Protease Inhibitors; Factor Xa Inhibitors; Antithrombins; Serine Proteinase Inhibitors; Anticoagulants; Enoxaparin; Fondaparinux; PENTA
• Other Study ID Numbers: NA_00025492