A Phase 4 interventional study of rivaroxaban (10mg) and Enoxaparin 40 mg SC in Deep Venous Thromboses and Laparotomy Patients, sponsored by Mayo Hospital Lahore. Recruiting at 1 site in Pakistan. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2025-11-21.
Sponsored by Mayo Hospital Lahore · Phase 4, Interventional, and Prevention
The goal of this clinical trial is to learn if rivaroxaban works better than enoxaparin to prevent deep vein thrombosis (DVT) after emergency exploratory laparotomy in adults. It will also learn about the safety of rivaroxaban compared to enoxaparin.
The main questions it aims to answer are:
Does rivaroxaban lower the number of patients who develop DVT after exploratory laparotomy compared to enoxaparin?
What medical problems or side effects do participants have when taking rivaroxaban versus enoxaparin?
Researchers will compare rivaroxaban (an oral anticoagulant) to enoxaparin (a subcutaneous injection) to see which drug works better to prevent blood clots after surgery.
Participants will:
Take rivaroxaban 10 mg orally once daily for 7 days, or enoxaparin 40 mg subcutaneously once daily for 7 days after surgery
Undergo duplex color Doppler ultrasound scans of the legs on day 5 and day 10 after surgery
Be monitored for bleeding, complications, and other side effects
Postoperative venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), is a major and preventable cause of morbidity and mortality after surgery. Patients undergoing emergency exploratory laparotomy are at especially high risk due to prolonged operative times, systemic inflammation, and immobility. While low-molecular-weight heparins (LMWH), such as enoxaparin, are the current standard for prophylaxis, direct oral anticoagulants such as rivaroxaban offer potential advantages in terms of ease of administration, compliance, and patient comfort.
This randomized controlled trial was designed to compare the efficacy and safety of once-daily oral rivaroxaban (10 mg) with once-daily subcutaneous enoxaparin (40 mg) in preventing postoperative DVT in adult patients undergoing emergency exploratory laparotomy at Mayo Hospital, Lahore.
Eligible patients were adults aged 18-80 years undergoing emergency laparotomy for traumatic or non-traumatic indications and expected to remain immobile for more than 24 hours postoperatively. Patients with pre-existing DVT, morbid obesity (BMI ≥40), active bleeding risk, mechanical ventilation, myocardial infarction, cerebrovascular accident, or current anticoagulation therapy were excluded.
Participants were randomized using a computer-generated sequence with allocation concealment. Rivaroxaban or enoxaparin was given for 7 days postoperatively, in addition to standard perioperative care and mechanical prophylaxis.
The primary outcome was the incidence of DVT as confirmed by duplex color Doppler ultrasound on postoperative days 5 and 10. Any noncompressible or indistinct venous segment was scored as positive for DVT. Wells scores were also recorded to stratify risk.
The secondary outcomes included bleeding complications, duration of hospital stay, time to ambulation, and cost comparison between the two regimens. Safety assessments focused on clinically significant bleeding events and other adverse reactions.
A total of 212 patients were enrolled (106 in each arm). On day 5, rivaroxaban showed a significantly lower rate of DVT compared to enoxaparin (3.8% vs 12.3%). By day 10, the difference remained significant (8.5% vs 20.8%). Wells scores showed no significant differences between groups. No major bleeding events were reported in either arm.
The findings suggest that rivaroxaban is more effective than enoxaparin in reducing postoperative DVT after emergency exploratory laparotomy without increasing bleeding risk. These results add evidence that rivaroxaban may be a safe and convenient alternative to LMWH for high-risk general surgical patients. However, larger multicenter trials with longer follow-up are needed to confirm safety and evaluate long-term outcomes such as pulmonary embolism and late-onset DVT.
785 studies on the registry are indexed under Venous Thrombosis; 110 are open to participants now.
This study's planned enrollment of 212 is above the median of 152 across 477 interventional studies indexed under Venous Thrombosis.
Browse Venous Thrombosis studies →Mayo Hospital Lahore is the lead sponsor of 16 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria:• Patients aged 18 to 80 years
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Arm 1 Title: Rivaroxaban Group Arm Type: Experimental Intervention Name: Drug: Rivaroxaban Descri
Drug: rivaroxaban (10mg)
Arm 2 Title: Enoxaparin Group Arm Type: Active Comparator Intervention Name: Drug: Enoxaparin Description: Participants receive enoxaparin 40 mg subcutaneously once daily for 7 days after emergency exploratory laparotomy, in addition to standard perioperative care and mechanical prophylaxis.
Drug: Enoxaparin 40 mg SC
Name: Drug: Rivaroxaban Type: Drug Description: Participants receive rivaroxaban 10 mg orally once daily for 7 days following emergency exploratory laparotomy. All patients also receive standard perioperative management and mechanical prophylaxis as per institutional guidelines.
Also known as: Xarelto
Name: Drug: Enoxaparin Type: Drug Description: Participants receive enoxaparin 40 mg subcutaneously once daily for 7 days following emergency exploratory laparotomy. All patients also receive standard perioperative management and mechanical prophylaxis as per institutional guidelines.
Also known as: clexane
Incidence of Deep Vein Thrombosis (DVT)
Presence of DVT in the lower limbs will be assessed by duplex color Doppler ultrasonography on postoperative day 5 and day 10. A noncompressible or indistinct venous segment on ultrasound will be considered positive for DVT. The outcome will be reported as the proportion of participants in each treatment arm who develop DVT.
Time frame: Postoperative Day 5 and Day 10
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No — The individual participant data (IPD) collected during the trial (including demographics, clinical variables, Wells scores, ultrasound results, and outcomes) will not be made publicly available. Only aggregated results will be reported in publications and presentations.
Started Oct 2025 (actual). Primary completion is estimated for Nov 2025, 1 month after the start.
Of 29 phase 4 interventional studies under Venous Thrombosis, half reached primary completion within 37 months of starting (the median), counting those still running; a quarter within 24 and three quarters within 49. This study's planned 1 month is below that.
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Studies of the drugs tested here: Rivaroxaban · Enoxaparin
Mayo Hospital Lahore