Recruiting

Surveillance vs. Anticoagulation

Sponsor:

Drahomir Aujesky

Code:

NCT04263038

Conditions

Pulmonary Embolism

Embolism

Embolism and Thrombosis

Lung Diseases

Cardiovascular Diseases

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Rivaroxaban

Placebo

Study Details

Brief summary:

The clinical significance of pulmonary embolism (PE) limited to the subsegmental pulmonary arteries, so called isolated subsegmental pulmonary embolism (SSPE), remains controversial. Whether isolated SSPE represents "true" PE, a clinically more benign form of PE, a physiologic lung clearing process, or a false positive result (artifact) is currently unclear and hence, whether patients with isolated SSPE benefit from anticoagulant treatment is uncertain. Despite growing evidence from observational studies that withholding anticoagulation may be a safe option in selected patients with isolated SSPE (i.e., those without concomitant deep vein thrombosis, cancer, etc.), most patients with isolated SSPE receive anticoagulant treatment, which is associated with an increased risk of bleeding. The overall objective of the randomized controlled SAFE-SSPE trial is to evaluate the efficacy and safety of clinical surveillance without anticoagulation compared to anticoagulation treatment in low-risk patients with isolated SSPE.

Conditions

Pulmonary Embolism

Embolism

Embolism and Thrombosis

Lung Diseases

Cardiovascular Diseases

Study ID

NCT04263038

Start date

May 15, 2020

Status verified date

May, 2026

Completion date

May, 2028

Anticipated

Primary completion date

May, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Informed Consent as documented by signature
2. Age ≥18 years
3. Objective diagnosis of symptomatic or asymptomatic isolated SSPE

Exclusion Criteria:

1. Presence of leg deep vein thrombosis (DVT) or upper extremity DVT (subclavian vein or above)
2. Active cancer, defined as cancer treated with surgery, chemotherapy, radiotherapy, or palliative care during the last 6 months
3. ≥1 prior episode of unprovoked VTE (absence of a transient or permanent risk factor)
4. Clinical instability (systolic blood pressure <100 mm Hg or arterial Oxygen saturation <92% at ambient air) at the time of presentation
5. Active bleeding or at high risk of bleeding
6. Severe renal failure (creatinine clearance <30ml/min)
7. Severe liver insufficiency (Child-Pugh B or C)
8. Concomitant use of strong CYP3A4 inhibitors or strong CYP3A4 inducers
9. Known hypersensitivity to rivaroxaban
10. Need for therapeutic anticoagulation for another reason
11. Therapeutic anticoagulation for >72 hours for any reason at the time of screening
12. Hospitalized for >72 hours prior to the diagnosis of isolated SSP (hospital-acquired VTE)
13. Known pregnancy or breast feeding (pregnancy test to be performed for women of childbearing potential)
14. Lack of safe contraception in women of childbearing potential
15. Refusal or inability to provide informed consent
16. Prior enrolment in this trial

Study Design

Enrollment

276 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

active comparator: Anticoagulation

Patients in the anticoagulation group will receive rivaroxaban 15 mg twice daily for the first 21 days, followed by 20 mg once daily for an overall treatment duration of 90 days.

placebo comparator: No anticoagulation

Patients in the group without anticoagulation will receive placebo twice daily for the first 21 days, followed by one tablet daily for an overall treatment duration of 90 days.

Interventions

Rivaroxaban

Anticoagulation

Placebo

Study drug without active agent

Primary outcome measure

  • Recurrent venous thromboembolism [ Time Frame: Within 90 days of randomization ]

Central Contacts and Locations

Central contacts

Drahomir Aujesky, Prof. MD MSc

+41 31 632 88 84SAFE-SSPE@insel.ch

Tobias Tritschler, Dr. MD MSc

+41 31 63 2 01 46SAFE-SSPE@insel.ch

Locations

The Ottawa Hospital

Recruiting

Ottawa, Canada

Principal Investigator:

Marc Carrier, Prof. MD MSc

More Information

Sponsor

Drahomir Aujesky

Last update posted

May 22, 2026

Last verified

May, 2026

Keywords

  • subsegmental pulmonary embolism

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Drahomir Aujesky on 2026-05-22.