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D-dimer to Establish Duration of Anticoagulation After Venous Thromboembolism

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT00264277
Recruitment Status : Completed
First Posted : December 12, 2005
Last Update Posted : March 19, 2021
Information provided by (Responsible Party):
GUALTIERO PALARETI, IRCCS Azienda Ospedaliero-Universitaria di Bologna

Brief Summary:
The optimal duration of oral anticoagulant treatment in patients with idiopathic venous thromboembolism is still uncertain. The present study addresses the possible role of the D-dimer test in assessing the need for continuation of anticoagulation.The study aims at assessing whether D-dimer assay may have a role in guiding the duration of anticoagulation in these patients

Condition or disease Intervention/treatment Phase
Deep Vein Thrombosis Pulmonary Embolism Drug: Vitamin K antagonist (Coumarin anticoagulants) Phase 4

Detailed Description:
This is a multicenter prospective follow-up study in patients with a first episode of symptomatic idiopathic venous thromboembolism (proximal deep vein thrombosis and/or pulmonary embolism) who are treated with vitamin K antagonists (either warfarin or acenocoumarol) for a minimum of 3 months. Eligible patients who give informed consent are instructed to immediately stop oral anticoagulation and refrain from taking any other antithrombotic drugs until the next visit, scheduled after 30 days. At that visit, venous blood is sampled to perform D-dimer assay and thrombophilia tests. D-dimers are assessed using the Clearview Simplify D-dimer assay (Agen Biomedical Limited, Brisbane, Australia). Patients with normal D-dimer results do not continue anticoagulation, whereas those with elevated D-dimer results are randomized using a computer program to either stop or resume anticoagulation with vitamin K antagonists (INR 2.0-3.0). All patients are followed-up for 18 months. The study outcome are the composite of confirmed recurrent venous thromboembolism and major bleeding events. All suspected outcome events and all deaths are evaluated by a central adjudication committee whose members are unaware of the D-dimer and thrombophilia results and of the group assignments.

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Study Type : Interventional  (Clinical Trial)
Enrollment : 600 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: D-dimer Test to Establish Duration of Anticoagulation After a First Idiopathic Episode of Venous Thromboembolism; the Prospective Randomized "Prolong" Study
Study Start Date : September 2002
Actual Primary Completion Date : December 2004
Actual Study Completion Date : September 2005

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Blood Thinners

Primary Outcome Measures :
  1. Confirmed recurrent proximal deep vein thrombosis and/or pulmonary embolism at 18 months follow up
  2. Confirmed major bleeding events at 18 months follow up

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age > 18 years
  • After a first documented idiopathic proximal deep vein thrombosis and/or pulmonary embolism
  • After at least 3 months of oral anticoagulation
  • After written informed consent

Exclusion Criteria:

  • If the Venous thromboembolism occurred:
  • during pregnancy or puerperium
  • after recent (i.e. within three months) fracture or plaster casting of a leg,
  • after immobilization with confinement to bed for three consecutive days
  • after surgery with general anesthesia lasting longer than 30 minutes
  • Patients with:
  • active cancer
  • antiphospholipid antibody syndrome
  • antithrombin deficiency
  • serious liver disease or renal insufficiency (creatininemia > 2 mg/dL),
  • other indications for anticoagulation or contraindications for this treatment
  • limited life expectation
  • Patients who live too far from the clinical center

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00264277

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Dept. of Angiology & Blood Coagulation, University Hospital S. Orsola-Malpighi
Bologna, BO, Italy, 40138
Sponsors and Collaborators
IRCCS Azienda Ospedaliero-Universitaria di Bologna
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Study Chair: GUALTIERO PALARETI, MD Head of Dept. Angiology & Blood Coagulation, University Hospital S. Orsola-Malpighi, Bologna, Italy
Publications of Results:
Other Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: GUALTIERO PALARETI, Professor, IRCCS Azienda Ospedaliero-Universitaria di Bologna
ClinicalTrials.gov Identifier: NCT00264277    
Other Study ID Numbers: PROLONG STUDY
First Posted: December 12, 2005    Key Record Dates
Last Update Posted: March 19, 2021
Last Verified: March 2021
Keywords provided by GUALTIERO PALARETI, IRCCS Azienda Ospedaliero-Universitaria di Bologna:
Venous Thromboembolism
Additional relevant MeSH terms:
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Pulmonary Embolism
Venous Thromboembolism
Venous Thrombosis
Embolism and Thrombosis
Vascular Diseases
Cardiovascular Diseases
Lung Diseases
Respiratory Tract Diseases
Vitamin K
Physiological Effects of Drugs
Antifibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action