Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis (ATTRACT)
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ClinicalTrials.gov Identifier: NCT00790335 |
Recruitment Status
:
Completed
First Posted
: November 13, 2008
Results First Posted
: March 29, 2018
Last Update Posted
: March 29, 2018
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Condition or disease | Intervention/treatment | Phase |
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Deep Vein Thrombosis Venous Thrombosis Postphlebitic Syndrome Venous Thromboembolism Post Thrombotic Syndrome | Drug: Recombinant tissue plasminogen activator (rt-PA) | Phase 3 |
Activase, the study drug, is a fibrinolytic drug that is indicated for use in acute myocardial infarction, acute ischemic stroke, and acute massive pulmonary embolism in adults. Previous studies have established the ability of rt-PA to lyse venous thrombus in patients with deep vein thrombosis (DVT), and suggest that successful rt-PA mediated thrombolysis can prevent the post-thrombotic syndrome (PTS), a morbid, late complication of DVT that occurs in nearly 50% of patients.
rt-PA is delivered directly into venous thrombus using a catheter/device which is embedded within the thrombus by a physician under imaging guidance. This method of rt-PA delivery, pharmacomechanical catheter-directed intrathrombus thrombolysis (PCDT),is thought to be safer, more effective, and more efficient than previous methods. The question of whether PCDT using rt-PA improves long-term DVT patient outcomes with acceptable risk and cost has not yet been addressed.
The rationale for performing the ATTRACT Trial is based upon:
- the major burden of PTS on DVT patients and the U.S. healthcare system
- the association between rapid clot lysis and prevention of PTS
- the proven ability of rt-PA to dissolve venous thrombus in proximal DVT
- recent advances in CDT methods which may lower bleeding risk
- the major clinical controversy on whether CDT should be routinely used for first-line DVT therapy
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 692 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis--The ATTRACT Trial |
Study Start Date : | November 2009 |
Actual Primary Completion Date : | January 2017 |
Actual Study Completion Date : | January 2017 |

Arm | Intervention/treatment |
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Experimental: A-Intervention
PCDT with intrathrombus delivery of recombinant tissue plasminogen activator (rt-PA, maximum allowable total dose 35 mg) into the DVT over a period of up to 24 hours. Three methods of initial rt-PA delivery will be used: 1) Trellis-8 Peripheral Infusion System - maximum first-session rt-PA dose 25 mg; 2) AngioJet Rheolytic Thrombectomy System - maximum first-session rt-PA dose 25 mg; or 3) Catheter-directed rt-PA infusion for up to 24 hours at 0.01 mg/kg/hr (maximum 1.0 mg/hr) via a multisidehole infusion catheter. Before and after PCDT, patients will receive standard DVT therapy as in the Control Arm
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Drug: Recombinant tissue plasminogen activator (rt-PA)
Pharmacomechanical catheter-directed thrombolysis, consisting of intrathrombus administration of rt-PA using a catheter/device.
Other Names:
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No Intervention: B-Control
Initial anticoagulant therapy with unfractionated heparin, enoxaparin, dalteparin, or tinzaparin, for at least 5 days, overlapped with long-term oral warfarin (target international normalized ratio 2.0 - 3.0). Elastic compression stockings will be prescribed
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- Cumulative Incidence of Post-Thrombotic Syndrome (Villalta Scale) [ Time Frame: Between 6 and 24 months after randomization ]Patients who experienced one of the following occurrences in the index leg between the 6 month and 24 month post-randomization follow-up visits, inclusive: 1) Villalta score of 5 or greater; 2) leg ulcer; or 3) late endovascular procedure performed to treat severe venous disease. The Villalta scale ranges from 0-33 points, with higher scores being worse.
- Major Non-post-thrombotic Syndrome Treatment Failure [ Time Frame: Through 24 months ]A major non-post-thrombotic-syndrome treatment failure refers to when any of three events occurred in the index leg: 1) an unplanned endovascular procedure to treat severe venous symptoms within 6 months post-randomization; 2) venous gangrene within 6 months; or 3) an amputation within 24 months.
- Any Treatment Failure [ Time Frame: Through 24 months ]Composite of PTS and major non-PTS treatment failure
- Moderate-to-severe Post-thrombotic Syndrome [ Time Frame: Between 6 and 24 months after randomization ]Proportion of patients with Villalta score of 10 or higher at any time between the 6 month and 24 month follow-up visits, inclusive. The Villalta scale ranges from 0-33 points, with higher scores being worse.
- Major Bleeding [ Time Frame: Within 10 days after randomization ]Defined as clinically overt bleeding that is associated with a fall in the hemoglobin level of at least 2.0 g/dl, transfusion of ≥ 2 units of red blood cells, or involvement of a critical site (e.g. intracranial, intraspinal).
- Major Bleeding [ Time Frame: Within 24 months after randomization ]Defined as clinically overt bleeding that was associated with a fall in the hemoglobin level of at least 2.0 g/dl, transfusion of ≥ 2 units of red blood cells, or involvement of a critical site (e.g. intracranial, intraspinal).
- Any (Minor + Major) Bleeding [ Time Frame: Within 10 days after randomization ]Clinically overt bleeding that occurred through 10 days post-randomization
- Any (Major + Minor) Bleeding [ Time Frame: Within 24 months after randomization ]Clinically overt bleeding that occurred within 24 months post-randomization
- Recurrent Venous Thromboembolism [ Time Frame: Within 10 days after randomization ]Proportion of patients with symptomatic recurrent venous thromboembolism (including DVT and/or PE)
- Recurrent Venous Thromboembolism [ Time Frame: Within 24 months after randomization ]Symptomatic recurrent venous thromboembolism (DVT and/or PE)
- Death [ Time Frame: Within 10 days after randomization ]All-cause mortality
- Death [ Time Frame: Within 24 months after randomization ]All-cause mortality
- Severity of Post-thrombotic Syndrome (Villalta) [ Time Frame: At 6 months ]Mean Villalta scale score at the specified follow-up visit. Villalta score ranges from 0-33 points, with higher scores being worse.
- Severity of Post-thrombotic Syndrome (Villalta) [ Time Frame: At 12 months ]Mean Villalta scale score at the specified follow-up visit. Villalta score ranges from 0-33 points, with higher scores being worse.
- Severity of Post-thrombotic Syndrome (Villalta) [ Time Frame: At 18 months ]Mean Villalta scale score at specified follow-up visit. Villalta score ranges from 0-33 points, with higher scores being worse.
- Severity of Post-thrombotic Syndrome (Villalta) [ Time Frame: At 24 months ]Mean Villalta scale score at specified follow-up visit. Villalta score ranges from 0-33 points, with higher scores being worse.
- Venous Clinical Severity Score [ Time Frame: At 6 months ]Mean Venous Clinical Severity Score (VCSS) at the specified follow-up visit; range 0-27 (did not use compression item), higher score is worse
- Venous Clinical Severity Score [ Time Frame: At 12 months ]Mean VCSS score at the specified follow-up visit; range 0-27 (did not use compression item)
- Venous Clinical Severity Score [ Time Frame: At 18 months ]Mean VCSS score at the specified follow-up visit; range 0-27 (did not use compression item)
- Venous Clinical Severity Score [ Time Frame: At 24 months ]Mean VCSS score at the specified follow-up visit; range 0-27 (did not use compression item)
- Change in General Quality of Life - Physical [ Time Frame: Baseline to 24 months post-randomization ]Short-Form-36 Health Survey, Version 2, Physical Component Summary (PCS) Scale. Range of scores 0-100 with higher scores representing better quality of life.
- Change in General Quality of Life - Mental [ Time Frame: Baseline to 24 months post-randomization ]Short-Form-36 Health Survey, Version 2, Mental Component Summary (MCS) Scale. Range of scores 0-100 with higher scores representing better quality of life.
- Change in Venous Disease-specific Quality of Life [ Time Frame: Baseline to 24 months post-randomization ]Venous Insufficiency Epidemiological and Economic Study Quality of Life (VEINES-QOL) questionnaire. Range of scores 0-100 with higher scores representing better quality of life, and higher change scores representing greater improvement from baseline.
- Change in Leg Pain Severity [ Time Frame: Baseline to 10 days post-randomization ]Likert pain scale ranging from 1-7, with higher scores representing a greater intensity of pain
- Change in Leg Pain Severity [ Time Frame: Baseline to 30 days post-randomization ]Likert pain scale ranging from 1-7, with higher scores representing a greater intensity of pain
- Change in Leg Circumference [ Time Frame: Baseline to 10 days post-randomization ]Mean calf circumference measured 10 cm below the tibial tuberosity
- Change in Leg Circumference [ Time Frame: Baseline to 30 days post-randomization ]Mean calf circumference measured 10 cm below the tibial tuberosity

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Ages Eligible for Study: | 16 Years to 75 Years (Child, Adult, Senior) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Symptomatic proximal DVT involving the iliac, common femoral, and/or femoral vein.
Exclusion Criteria:
- Age less than 16 years or greater than 75 years.
- Symptom duration > 14 days for the DVT episode in the index leg (i.e., non-acute DVT).
- In the index leg: established PTS, or previous symptomatic DVT within the last 2 years.
- In the contralateral (non-index) leg: symptomatic acute DVT a) involving the iliac and/or common femoral vein; or b) for which thrombolysis is planned as part of the initial therapy.
- Limb-threatening circulatory compromise.
- Pulmonary embolism with hemodynamic compromise (i.e., hypotension).
- Inability to tolerate PCDT procedure due to severe dyspnea or acute systemic illness.
- Allergy, hypersensitivity, or thrombocytopenia from heparin, rt-PA, or iodinated contrast, except for mild-moderate contrast allergies for which steroid pre-medication can be used.
- Hemoglobin < 9.0 mg/dl, INR > 1.6 before warfarin was started, or platelets < 100,000/ml.
- Moderate renal impairment in diabetic patients (estimated glomerular filtration rate [GFR] < 60 ml/min) or severe renal impairment in non-diabetic patients (estimated GFR < 30 ml/min).
- Active bleeding, recent (< 3 mo) GI bleeding, severe liver dysfunction, bleeding diathesis.
- Recent (< 3 mo) internal eye surgery or hemorrhagic retinopathy; recent (< 10 days) major surgery, cataract surgery, trauma, cardiopulmonary resuscitation, obstetrical delivery, or other invasive procedure.
- History of stroke or intracranial/intraspinal bleed, tumor, vascular malformation, aneurysm.
- Active cancer (metastatic, progressive, or treated within the last 6 months). Exception: patients with non-melanoma primary skin cancers are eligible to participate in the study.
- Severe hypertension on repeated readings (systolic > 180 mmHg or diastolic > 105 mmHg).
- Pregnant (positive pregnancy test, women of childbearing potential must be tested).
- Recently (< 1 mo) had thrombolysis or is participating in another investigational drug study.
- Use of a thienopyridine antiplatelet drug (except clopidogrel) in the last 5 days.
- Life expectancy < 2 years or chronic non-ambulatory status.
- Inability to provide informed consent or to comply with study assessments (e.g. due to cognitive impairment or geographic distance).

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): NCT00790335

Principal Investigator: | Suresh Vedantham, M.D. | Clinical Coordinating Center at Washington University School of Medicine | |
Principal Investigator: | Clive Kearon, MB, MRCP, FRCP(C), PhD | Data Coordinating Center at McMaster University-Ontario Clinical Oncology Group | |
Study Chair: | Samuel Z Goldhaber, M.D. | Brigham and Women's Hospital |
Additional Information:
Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Washington University School of Medicine |
ClinicalTrials.gov Identifier: | NCT00790335 History of Changes |
Other Study ID Numbers: |
22326953211 U01HL088476-01A1 ( U.S. NIH Grant/Contract ) |
First Posted: | November 13, 2008 Key Record Dates |
Results First Posted: | March 29, 2018 |
Last Update Posted: | March 29, 2018 |
Last Verified: | February 2018 |
Keywords provided by Washington University School of Medicine:
deep vein thrombosis deep venous thrombosis post thrombotic syndrome blood clot thrombolysis tissue plasminogen activator |
rt-PA Activase mechanical thrombectomy pharmacomechanical ATTRACT |
Additional relevant MeSH terms:
Syndrome Thrombosis Thromboembolism Venous Thromboembolism Venous Thrombosis Postthrombotic Syndrome Postphlebitic Syndrome Disease Pathologic Processes Embolism and Thrombosis |
Vascular Diseases Cardiovascular Diseases Venous Insufficiency Phlebitis Peripheral Vascular Diseases Plasminogen Tissue Plasminogen Activator Fibrinolytic Agents Fibrin Modulating Agents Molecular Mechanisms of Pharmacological Action |