Recruiting
Phase 2
Phase 3

Rivaroxaban

Sponsor:

Ottawa Hospital Research Institute

Code:

NCT06965998

Conditions

SVT

Thrombosis

Superficial Vein Thrombosis

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Full dose rivaroxaban

Low dose rivaroxaban

Placebo

Study Details

Brief summary:

The goal of this clinical trial, called a pilot study or a feasibility study, is to test the study plan and to find out whether enough participants will join a larger study and accept the study procedures. This type of study includes a small number of participants so it is not expected to prove how safe the treatment is or how well the treatment works.

The main question it hopes to answer is:

1.What is the average number of patients that are recruited per month during the 12 month study period?

To test the study plan, adults being treated for a superficial vein thrombosis (SVT), which is a blood clot in the superficial veins of the leg, will be given a type of blood thinner called rivaroxaban. Half of the participants in this study will be given the standard (low-dose) rivaroxaban for 45 days, then 45 days of placebo (a substance that looks like the study medication but does not have any active or medicinal ingredients). The other half of participants will be given full-dose rivaroxaban for a total of 90 days. The placebo in this study is not intended to have any effect on the participants blood clot. A placebo is used to make the results of the study more reliable.

Conditions

SVT

Thrombosis

Superficial Vein Thrombosis

Study ID

NCT06965998

Start date

Aug 6, 2025

Status verified date

Aug, 2025

Completion date

Feb, 2027

Anticipated

Primary completion date

Aug, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Adult patients age ≥ 18 years old.
2. Objectively confirmed diagnosis within 14 days of an acute symptomatic SVT of the lower extremities by standardized CUS, where SVT is defined as incompressibility of a venous segment located along the course of a known superficial vein.
3. Anticoagulation for SVT is warranted per clinicians.
4. Able and willing to provide written informed consent.

Exclusion Criteria:

1. Other indication(s) for therapeutic or prophylactic dose anticoagulation (e.g. atrial fibrillation, mechanical valve, etc.).
2. History of PE or DVT within 6 months (180 days) of screening.
3. >5 days of any anticoagulants for the index SVT.
4. Requires use of aspirin >100mg daily or other antiplatelet agents.
5. Patients receiving concomitant systemic treatment with strong inhibitors of both CYP 3A4 and P-gp (e.g. cobicistat, ketoconazole, itraconazole, posaconazole, ritanovir, etc.).
6. Active bleeding or history of CRNMB or major bleeding (as defined by the ISTH) within 30 days of screening.
7. History of severe head trauma or ophthalmic, spinal, cerebral surgery within 90 days of screening.
8. Have acute endocarditis.
9. Thrombocytopenia (platelet count <50,000/uL), acute hepatitis, chronic active hepatitis, cirrhosis with severe hepatic impairment defined by a Childs-Pugh class B or C.
10. Creatinine clearance <30 ml/min.
11. Known contraindication to treatment with rivaroxaban.
12. Are participating in another interventional trial that would compromise the results or integrity of this trial as determined by the investigator.
13. Pregnant or breast feeding.
14. Known hereditary or acquired severe hemorrhagic disease.
15. Life expectancy <3 months.
16. Unstable medical or psychological condition that would interfere with trial participation at the discretion of the site investigator.

Study Design

Enrollment

50 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Group A (Intervention)

Day 1-21: 15mg Rivaroxaban twice per day Day 22-90: 20mg Rivaroxaban once a day for 69 days

active comparator: Group B (Comparator)

Day 1-21: 10mg Rivaroxaban once a day AND placebo once a day Day 22-45: 10mg Rivaroxaban once a day Day 46-90: Placebo once a day for 45 days

Interventions

Full dose rivaroxaban

The intervention group will receive full dose rivaroxaban for 90 days.

Low dose rivaroxaban

The comparator group will receive the standard treatment of low dose rivaroxaban.

Placebo

Since the treatment arm has an AM and PM dose of study drug from Day 1-21, the comparator group will take 1 placebo pill in the PM to keep the two arms blinded.

Primary outcome measure

  • Primary Feasibility Outcome [ Time Frame: 12 months from when recruitment opens. ]

Central Contacts and Locations

Central contacts

Tzu-Fei Wang, MD,MPH

613-737-9988tzwang@toh.ca

Miriam Kimpton, MD,MSc,FRCPC

mkimpton@toh.ca

Locations

The Ottawa Hospital

Recruiting

Ottawa, Ontario, Canada, K1H 8L6

Contacts

Veronica Bates, BSc, CCRP

613-737-8899vebates@ohri.ca

Principal Investigator:

Tzu-Fei Wang, MD, MPH

More Information

Sponsor

Ottawa Hospital Research Institute

Last update posted

Aug 11, 2025

Last verified

Aug, 2025

Keywords

  • Pilot
  • Rivaroxaban
  • Feasibility
  • Full dose rivaroxaban
  • Treatment dose rivaroxaban
  • Superficial vein thrombosis

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Ottawa Hospital Research Institute on 2025-08-11.