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Clopidogrel/Aspirin Interaction Study (INTERACTION)

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. Identifier: NCT01102439
Recruitment Status : Completed
First Posted : April 13, 2010
Last Update Posted : April 28, 2015
Information provided by (Responsible Party):
John Eikelboom, Population Health Research Institute

Brief Summary:
This study will explore the effect of different doses of aspirin on the effects of double-dose or standard dose clopidogrel.

Condition or disease Intervention/treatment Phase
Coronary Artery Disease Drug: Clopidogrel Drug: Aspirin Phase 4

Detailed Description:
Study Hypothesis: Patients receiving double-dose compared with standard-dose clopidogrel will have increased blood concentrations of the active metabolite of clopidogrel and greater inhibition of ADP-induced platelet aggregation when also treated with acetylsalicylic acid (ASA) 325 mg/d as compared to ASA 81 mg/d.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 82 participants
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Randomized, Factorial Study to Explore Interaction Between Aspirin and Clopidogrel in Stable Patients With Previous Myocardial Infarction or Coronary Artery Stent
Study Start Date : April 2010
Actual Primary Completion Date : December 2010
Actual Study Completion Date : February 2013

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Drug Reactions

Arm Intervention/treatment
Active Comparator: Standard dose clopidogrel
300 mg Loading x 1 day, 75 mg/d x 13 days
Drug: Clopidogrel
300 mg loading dose, then 75 mg daily
Other Name: Plavix

Experimental: Double dose clopidogrel
600 mg Loading x 1 day, 150 mg/d x 6 days, 75 mg/d x 7 days
Drug: Clopidogrel
600 mg loading dose, 150 mg daily day 2-7, then 75 mg daily
Other Name: Plavix

Active Comparator: Standard dose aspirin
Aspirin 81mg/d x 14 days
Drug: Aspirin
81 mg daily
Other Name: Entrophen

Experimental: High dose aspirin
Aspirin 325 mg/d x 14 days
Drug: Aspirin
325 mg daily
Other Name: Novasen

Primary Outcome Measures :
  1. Blood concentrations of the active metabolite of clopidogrel [ Time Frame: 14 days ]

Secondary Outcome Measures :
  1. Inhibition of adenosine diphosphate (ADP) induced platelet aggregation [ Time Frame: 14 days ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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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:

  • > 1 month post myocardial infarction (MI), unstable angina or stent patients with stable condition
  • Receiving regular ASA (81mg/d) and clopidogrel (75mg/d) for at least 1 week
  • Written informed consent

Exclusion Criteria:

  • Age < 18 years old
  • Liver disease with transaminases and/or bilirubin > 1.5x upper limits of normal (ULN) (within 3 months of randomization)
  • Renal impairment with creatinine clearance < 30 ml/min (within 3 months of randomization)
  • Platelet count < 100x109/L and/or Hb< 100g/L (within 3 months of randomization)
  • Use of oral anticoagulants or nonsteroidal antiinflammatory drug (NSAID) within the last 10 days or planned use during the study
  • Use of antiplatelet agent other than aspirin and clopidogrel within the last 10 days
  • High risk of bleeding (e.g. recent gastrointestinal bleeding, bleeding diathesis)
  • Uncontrolled hypertension (> 180/110mmHg)
  • Current smoker with ≥ 5 cigarettes/day
  • Previously entered in this study or just finished other study within 2 weeks before recruitment
  • Medical, geographic, or social factors making study participation impractical, or inability to provide written informed consent

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 identifier (NCT number): NCT01102439

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Canada, Ontario
Population Health Research Institute
Hamilton, Ontario, Canada, L8L 2X2
Sponsors and Collaborators
Population Health Research Institute
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Principal Investigator: Yan Liang, MD Population Health Research Institute
Study Director: John Eikelboom, MD. Population Health Research Institute
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Responsible Party: John Eikelboom, MD., Population Health Research Institute Identifier: NCT01102439    
Other Study ID Numbers: 10-082
First Posted: April 13, 2010    Key Record Dates
Last Update Posted: April 28, 2015
Last Verified: April 2015
Keywords provided by John Eikelboom, Population Health Research Institute:
Additional relevant MeSH terms:
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Purinergic P2Y Receptor Antagonists
Purinergic P2 Receptor Antagonists
Purinergic Antagonists
Purinergic Agents
Coronary Artery Disease
Coronary Disease
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Arterial Occlusive Diseases
Vascular Diseases
Anti-Inflammatory Agents, Non-Steroidal
Analgesics, Non-Narcotic
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Inflammatory Agents
Antirheumatic Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Cyclooxygenase Inhibitors
Enzyme Inhibitors
Neurotransmitter Agents