Apixaban vs Enoxaparin Following Microsurgical Breast Reconstruction-An RCT

NCT04504318 | Completed Phase 1 Results FDA Drug

• 1 other identifier: IRB-49355
• Study Type: interventional
• Target: 82
• Locations: 1 country
• Sites: 1

Brief Summary

Subcutaneous enoxaparin is currently the gold standard for VTE chemoprophylaxis. However, the efficacy of chemoprophylaxis with subcutaneous enoxaparin is affected by patient-level factors, thus, resulting in VTE events despite guideline-compliant prophylaxis. A population at particular risk is the growing number of patients who undergo autologous breast reconstruction. Direct oral anticoagulants (DOAC) might be a less invasive, yet, more efficacious mode of chemoprophylaxis in this patient population. Hence, the proposed work has the potential to cause a paradigm shift in chemoprophylaxis guidelines in a large population of patients undergoing plastic surgery.

Conditions

Venous Thromboembolism

Outcome Measures

Primary Outcomes (1)

• Apixaban vs. Enoxaparin - Number of Participants With Bleeding Events

  To examine the rate of bleeding events in patients receiving oral apixaban versus subcutaneous enoxaparin following microsurgical breast reconstruction

  90-day events

Secondary Outcomes (1)

• Apixaban vs. Enoxaparin - Number of Participants With Venous Thromboembolism (VTE) Events

  90 days

Study Arms (2)

Apixaban

EXPERIMENTAL

Patients assigned to this group will receive Apixaban 2.5 mg PO BID starting 12 hours after completing skin closure.

Drug: Apixaban 2.5 MG Oral Tablet

Enoxaparin

ACTIVE COMPARATOR

Patients assigned to this group will receive Enoxaparin 40 mg SC QD starting 12 hours after completing skin closure.

Drug: Enoxaparin 40Mg/0.4mL Prefilled Syringe

Interventions

Apixaban 2.5 MG Oral Tablet DRUG

Patients will be assigned to the respective study groups postoperatively upon arrival in the post-anesthesia care unit. Hence, surgeons are blinded at the time of surgery as to study group assignment. Chemoprophylaxis will continue for the duration of the hospitalization.

Apixaban

Enoxaparin 40Mg/0.4mL Prefilled Syringe DRUG

Patients will be assigned to the respective study groups postoperatively upon arrival in the post-anesthesia care unit. Hence, surgeons are blinded at the time of surgery as to study group assignment. Chemoprophylaxis will continue for the duration of the hospitalization.

Enoxaparin

Eligibility Criteria

• Age: 18 Years - 89 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult (\>18 years) women
• Scheduled to undergo unilateral or bilateral microsurgical breast reconstruction with free abdominal flaps (i.e. muscle-sparing transverse rectus abdominis musculocutaneous \[TRAM\] and/or deep inferior epigastric artery perforator \[DIEP\]) flap)
• Caprini score of 6 or greater.
• Ability to understand and the willingness to sign a written informed consent document.

You may not qualify if:

• Contraindication to the use of apixaban or enoxaparin
• Active bleeding
• History of bleeding disorder
• History of coagulopathy
• History of heparin-induced thrombocytopenia
• History of liver disease
• History of renal disease (creatinine clearance \<30 mL/min; serum creatinine \>1.6 mg/dL)
• Major neurosurgical intervention (brain/spine) within the past 90 days
• Ophthalmologic procedure within the past 90 days
• Uncontrolled hypertension
• History of alcohol and/or substance abuse
• Need for therapeutic anticoagulation
• Pregnant or Nursing

Sponsors & Collaborators

• Stanford University: lead

Study Sites (1)

Stanford University Medical Center

Stanford, California, 94305, United States

Location

MeSH Terms

Conditions

Venous Thromboembolism

Interventions

apixaban; Tablets; Enoxaparin

Condition Hierarchy (Ancestors)

Thromboembolism; Embolism and Thrombosis; Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Dosage Forms; Pharmaceutical Preparations; Heparin, Low-Molecular-Weight; Heparin; Glycosaminoglycans; Polysaccharides; Carbohydrates

Results Point of Contact

• Title: Dr. Arash Momeni
• Organization: Stanford University

amomeni@stanford.edu

650-723-6189

Study Officials

• Arash Momeni, MD

  Stanford University

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: CARE PROVIDER
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Surgery (Plastic Surgery)

Study Record Dates

• First Submitted: August 5, 2020
• First Posted: August 7, 2020
• Study Start: August 12, 2020
• Primary Completion: June 19, 2024
• Study Completion: June 19, 2024
• Last Updated: June 22, 2025
• Results First Posted: June 22, 2025

Record last verified: 2025-06

Locations

US (1)