Resistance to Antithrombotic Therapy

Not Applicable

Completed

• Conditions: Atherosclerosis; Angioplasty
• Interventions: Drug: aspirin; Drug: clopidogrel

• Registration Number: NCT00858715
• Lead Sponsor: Medical University of Vienna

Brief Summary

Clopidogrel plays a pivotal role in the antithrombotic regimen after percutaneous intervention with stent implantation. However, response to clopidogrel shows a wide interindividual variability and a high on-treatment residual ADP-inducible platelet reactivity has already been associated with an increased risk for adverse events after coronary stenting. In the present study, platelet reactivity will be determined by 6 different platelet function tests in patients on dual antiplatelet therapy after angioplasty and stenting for peripheral, coronary and carotid artery disease. One hundred patients showing high on-treatment residual ADP-inducible platelet reactivity in 2 or more tests will be randomized to receive either 75mg or 150mg of daily clopidogrel in addition to aspirin for 3 months. The aim of the present study is to investigate the effects of intensified antithrombotic therapy (150mg clopidogrel + 100mg aspirin daily) versus standard antithrombotic therapy (75mg clopidogrel + 100mg aspirin daily) in patients with decreased clopidogrel-mediated platelet inhibition after percutaneous intervention with stent implantation.

Detailed Description

Not available

Study Timeline

• Study Start: 2008-05
• Study First Submitted: 2009-03-09
• Study First Submitted QC: 2009-03-09
• Study First Posted: 2009-03-10
• Primary Completion: 2012-05
• Study Completion: 2012-05
• Status Verified: 2012-12
• Last Update Submitted: 2012-12-11
• Last Update Posted: 2012-12-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 46

Inclusion Criteria

• written informed consent
• angioplasty and stenting for peripheral, coronary or carotid artery disease

Exclusion Criteria

• known aspirin or clopidogrel intolerance
• therapy with vitamin K antagonists (warfarin, phenprocoumon, acenocoumarol)
• treatment with ticlopidine, dipyridamol or nonsteroidal antiinflammatory drugs
• family or personal history of bleeding disorders
• malignant paraproteinemias
• myeloproliferative disorders
• heparin-induced thrombocytopenia
• severe hepatic failure
• known qualitative defects in thrombocyte function
• major surgical procedure within one week before enrollment
• platelet count < 100.000 or > 450.000/µl
• hemoglobin < 8 g/dl

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
1	aspirin	75 mg clopidogrel + 100 mg aspirin
2	aspirin	150 mg clopidogrel + 100 mg aspirin
1	clopidogrel	75 mg clopidogrel + 100 mg aspirin
2	clopidogrel	150 mg clopidogrel + 100 mg aspirin

Primary Outcome Measures

Name	Time	Method
Occurence of major adverse cardiovascular events (MACE)	12 months

Trial Locations

Locations (1)

Division of Angiology, Department of Internal Medicine II, Medical University of Vienna; 🇦🇹 Vienna, Austria