Aspirin vs LMWH for Blood Clot Prevention in Orthopaedic Cancer Surgery

Recruiting at 9 trial locations

Age: 18+

Sex: Any

Trial Phase: Phase 4

Sponsor: Massachusetts General Hospital

Must be taking: Anticoagulants

Must not be taking: Full-strength aspirin

Disqualifiers: VTE history, Hypercoagulable state, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 4 weeks

2868 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are using certain anticoagulants or full-strength aspirin before surgery. It's best to discuss your current medications with the trial team.

What data supports the effectiveness of the drugs aspirin and enoxaparin for preventing blood clots in orthopedic cancer surgery?

Research shows that enoxaparin, a type of low molecular weight heparin, is more effective than aspirin in preventing deep vein thrombosis (a type of blood clot) after orthopedic surgery. However, aspirin combined with mechanical devices can be as effective as enoxaparin for preventing venous thromboembolism (blood clots in veins) after such surgeries. ^{1 2 3 4 5}

Is it safe to use aspirin or LMWH for blood clot prevention after orthopedic surgery?

Research shows that both aspirin and low molecular weight heparin (LMWH) are generally safe for preventing blood clots after orthopedic surgery. There are no significant differences in death rates, wound infections, or complications between the two, although aspirin alone may have a higher risk of deep vein thrombosis (DVT) compared to LMWH. ^{2 4 5 6 7}

How does the drug aspirin differ from low molecular weight heparin (LMWH) for preventing blood clots after orthopedic cancer surgery?

Aspirin is a simpler and more accessible option compared to low molecular weight heparin (LMWH), which is typically injected. While both are used to prevent blood clots after surgery, aspirin is often combined with mechanical devices to enhance its effectiveness, whereas LMWH is generally considered more effective on its own for preventing deep vein thrombosis (DVT). ^{1 2 5 8 9}

What is the purpose of this trial?

Aspirin and low molecular weight heparin (LMWH) are both commonly employed pharmacologic methods of venous thromboembolism (VTE) prophylaxis after orthopaedic surgery. Data comparing these two methods of VTE prophylaxis in patients undergoing pelvic/lower extremity orthopaedic surgery for malignancy are lacking, however, as compared to the data and guidelines present for VTE chemoprophylaxis after joint arthroplasty and hip fracture surgery. In this clinical trial, our specific aim is to compare the post operative incidence of VTE between patients receiving aspirin and LMWH after pelvic/lower extremity orthopaedic oncology procedures.

Research Team

Santiago A Lozano-Calderon, MD, PhD

Principal Investigator

Massachusetts General Hospital

Eligibility Criteria

This trial is for adults with bone or soft tissue sarcomas in the lower body who are undergoing certain surgeries. It's not for those unable to consent, pregnant, needle-phobic, with a history of blood clots or allergies to study drugs, IVC filter presence, known clotting disorders (except cancer), on full-strength aspirin or other anticoagulants pre-surgery.

Inclusion Criteria

I have had surgery for bone metastasis in my legs or pelvis.

I had surgery for bone cancer in my legs or pelvis.

I have a soft tissue sarcoma in my leg or pelvis and am receiving specific treatments.

Exclusion Criteria

Pregnancy

I cannot give myself injections.

Situation in which the attending surgeon does not feel that randomization of a subject would be appropriate

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either aspirin or low molecular weight heparin (LMWH) for VTE prophylaxis after pelvic/lower extremity orthopaedic oncology surgery

4 weeks

Weekly visits (in-person or virtual)

Follow-up

Participants are monitored for safety and effectiveness, including incidence of VTE, hematoma formation, and wound complications

Up to 6 months

Monthly visits (in-person or virtual)

Treatment Details

Interventions

• Aspirin
• Enoxaparin

Trial Overview The trial compares Aspirin (325mg) and Enoxaparin (a low molecular weight heparin) as methods to prevent blood clots after orthopaedic surgery for patients with pelvic/lower extremity cancers. The goal is to see which drug better prevents postoperative VTE.

Participant Groups

Group I: LMWH for Soft Tissue Sarcoma Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity soft tissue sarcomas and are randomized to Enoxaparin 40Mg/0.4mL prefilled syringe subcutaneous injection daily for VTE prophylaxis

Group II: LMWH for Primary Bone Tumor Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity primary bone tumor and are randomized to Enoxaparin 40Mg/0.4mL prefilled syringe subcutaneous injection daily for VTE prophylaxis

Group III: LMWH for Metastatic Disease Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity metastatic bone disease and are randomized to Enoxaparin 40Mg/0.4mL prefilled syringe subcutaneous injection daily for VTE prophylaxis

Group IV: ASA for Soft Tissue Sarcoma Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity soft tissue sarcomas and are randomized to aspirin 325 mg po daily for VTE prophylaxis

Group V: ASA for Primary Bone Tumor Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity primary bone tumor and are randomized to aspirin 325 mg po daily for VTE prophylaxis

Group VI: ASA for Metastatic Disease Experimental Treatment 1 Intervention

Patients undergoing surgery for pelvic/lower extremity metastatic bone disease and are randomized to aspirin 325 mg po daily for VTE prophylaxis

Aspirin is already approved in European Union, United States, Canada, China for the following indications:

Approved in European Union as Aspirin for:

• Pain relief
• Fever reduction
• Inflammation
• Cardiovascular disease prevention
• Preeclampsia prevention

Approved in United States as Aspirin for:

• Pain relief
• Fever reduction
• Inflammation
• Cardiovascular disease prevention
• Preeclampsia prevention

Approved in Canada as Aspirin for:

• Pain relief
• Fever reduction
• Inflammation
• Cardiovascular disease prevention
• Preeclampsia prevention

Approved in China as Aspirin for:

• Pain relief
• Fever reduction
• Inflammation
• Cardiovascular disease prevention

Who Is Running the Clinical Trial?

Massachusetts General Hospital

Lead Sponsor

Trials

3,066

Recruited

13,430,000+

Brigham and Women's Hospital

Collaborator

Trials

1,694

Recruited

14,790,000+

Beth Israel Deaconess Medical Center

Collaborator

Trials

872

Recruited

12,930,000+

Findings from Research

In a study of 85,938 patients undergoing hip or knee arthroplasty, aspirin was associated with significantly lower odds of bleeding complications compared to enoxaparin, making it a safer option for thromboprophylaxis.

While rivaroxaban also showed a trend toward increased bleeding compared to aspirin, the differences were not statistically significant, suggesting that aspirin may be the preferred choice for minimizing bleeding risks post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A retrospective analysis of bleeding risk with rivaroxaban, enoxaparin, and aspirin following total joint arthroplasty or revision. Watts, PJ., Kopstein, M., Harkness, W., et al.[2022]

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

Low molecular weight heparin and aspirin for prevention of deep vein thrombosisafter orthopaedic surgery: a systematic review and meta-analysis. [2022]

2. Poland pubmed.ncbi.nlm.nih.gov

Aspirin versus LMWH for VTE prophylaxis after orthopedic surgery. [2023]

3. Switzerland pubmed.ncbi.nlm.nih.gov

Assessment of bleeding after concomitant administration of antiplatelet and anticoagulant agents in lower limb arthroplasty. [2013]

4. France pubmed.ncbi.nlm.nih.gov

Aspirin versus enoxaparin for the initial prevention of venous thromboembolism following elective arthroplasty of the hip or knee: A systematic review and meta-analysis. [2021]

5. Spain pubmed.ncbi.nlm.nih.gov

Risk of venous thromboembolism in thromboprophylaxis between aspirin and low molecular weight heparins after total hip arthroplasty or total knee arthroplasty: Systematic review and meta-analysis. [2023]

6. United States pubmed.ncbi.nlm.nih.gov

Aspirin Is as Effective as and Safer Than Warfarin for Patients at Higher Risk of Venous Thromboembolism Undergoing Total Joint Arthroplasty. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

A retrospective analysis of bleeding risk with rivaroxaban, enoxaparin, and aspirin following total joint arthroplasty or revision. [2022]

8. United States pubmed.ncbi.nlm.nih.gov

Risk-stratified thromboprophylaxis effects of aspirin versus low-molecular-weight heparin in orthopaedic trauma patients: a secondary analysis of the PREVENT CLOT trial. [2023]

9. England pubmed.ncbi.nlm.nih.gov

PREVENTion of CLots in Orthopaedic Trauma (PREVENT CLOT): a randomised pragmatic trial protocol comparing aspirin versus low-molecular-weight heparin for blood clot prevention in orthopaedic trauma patients. [2021]