A Phase 4 interventional study of Rivaroxaban and Placebo in Pulmonary Embolism, Embolism and Embolism and Thrombosis, sponsored by Drahomir Aujesky. Recruiting at 40 sites in 5 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-22.
Sponsored by Drahomir Aujesky · Phase 4, Interventional, and Treatment
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.
832 studies on the registry are indexed under Pulmonary Embolism; 171 are open to participants now.
This study's planned enrollment of 276 is above the median of 174 across 429 interventional studies indexed under Pulmonary Embolism.
Browse Pulmonary Embolism studies →This is the only study on the registry with Drahomir Aujesky as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Drug: Rivaroxaban
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.
Drug: Placebo
Anticoagulation
Study drug without active agent
Recurrent venous thromboembolism
Proportion of recurrent, clinically symptomatic, objectively confirmed venous thromboembolism (defined as recurrent fatal or nonfatal pulmonary embolism or lower limb deep vein thrombosis)
Time frame: Within 90 days of randomization
Clinically significant bleeding
Proportion of the composite of major and clinically relevant non-major bleeding
Time frame: Within 90 days of randomization
All-cause mortality
Proportion of deaths (all causes of death will be considered)
Time frame: Within 90 days of randomization
Health-related quality of life
Pulmonary embolism related quality of life as assessed by the Pulmonary Embolism Quality of Life (PEmb-QoL) questionnaire
Time frame: Within 90 days of randomization
Functional status
Functional status as assessed by the post-venous thromboembolism functional status scale
Time frame: Within 90 days of randomization
Initial length of stay (LOS)
Defined as the time/date of discharge minus time/date of admission at the emergency department
Time frame: Within 90 days of randomization
Subsequent overall hospitalizations
Number of overall hospitalizations
Time frame: Within 90 days of randomization
Emergency departments and physician outpatient visits
Number of emergency department and physician outpatient visits
Time frame: Within 90 days of randomization
Return to work or usual activities
Time (days) to return to work in workers and usual activities (household) in non-workers
Time frame: Within 90 days of randomization
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Plan to share: Yes — After publication of the study results, a de-identified patient-level data set relating to the primary publication along with the latest version of the study protocol, the informed consent form, the statistical analysis plan, the code used for the analyses, and the Data Management and Quality Plan describing all data management aspects of the study will be made publicly available for replication of the study results and secondary data analyses in the Bern Open Repository and Information System (BORIS) Research Data, an online non-commercial data repository that meets Swiss National Science Foundation requirements for FAIR Data Principles (www.force11.org/group/fairgroup/fairprinciples)
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Analytic code
Time frame: After publication of the study results
Access criteria: Data will be publicly available for replication of the study results and secondary data analyses in the Bern Open Repository and Information System (BORIS) Research Data
Data sharing details ↗ · www.boris.unibe.ch
Started May 2020 (actual). Primary completion is estimated for May 2028, 96 months after the start.
Of 24 phase 4 interventional studies under Pulmonary Embolism, half reached primary completion within 47 months of starting (the median), counting those still running; a quarter within 32 and three quarters within 82. This study's planned 96 months is above that.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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Studies of the drug tested here: Rivaroxaban