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Trial record 49 of 632 for:    ASPIRIN AND clopidogrel

Resistance to Aspirin and/or Clopidogrel Among Patients With PAD.

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: NCT00262561
Recruitment Status : Completed
First Posted : December 7, 2005
Last Update Posted : January 28, 2014
Danish Heart Foundation
Information provided by (Responsible Party):
Esben Hjorth Madsen, Aalborg University Hospital

Tracking Information
First Submitted Date  ICMJE December 6, 2005
First Posted Date  ICMJE December 7, 2005
Last Update Posted Date January 28, 2014
Study Start Date  ICMJE January 2006
Actual Primary Completion Date January 2008   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: January 25, 2014)
Myocardial infarction, Unstable angina, Cerebral infarction, Transitory cerebral ischaemia, Percutaneous or surgical vascular intervention, Sudden deterioration of symptoms, Amputation, Death. [ Time Frame: 5 years ]
Original Primary Outcome Measures  ICMJE
 (submitted: December 6, 2005)
  • Myocardial infarction
  • Unstable angina
  • Cerebral infarction
  • Transitory cerebral ischaemia
  • Percutaneous or sugical vascular intervention
  • Sudden deterioration of symptoms
  • Amputation
  • Death
Change History
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Resistance to Aspirin and/or Clopidogrel Among Patients With PAD.
Official Title  ICMJE Prevalence of Resistance to Aspirin and/or Clopidogrel Among Patients With PAD. Prognostic Significance of Resistance to Aspirin
Brief Summary

263 patients with peripheral atherosclerosis were examined to evaluate the activity of the platelets during the standard treatment, including aspirin. A subgroup of 43 received 600 mg of clopidogrel 2 h before platelet reactivity analysis.

The main hypothesis is that high platelet activity at the beginning of the study is associated with a higher risk of atherothrombosis. Follow up time is 5 years.

Detailed Description

Patients with peripheral atherosclerosis are at high risk of atherothrombosis, mainly heart attack and stroke. The medical treatment of these patients include platelet inhibiting drugs, usually aspirin, to reduce the risk of ischemic events. Clopidogrel is another platelet inhibiting drug, which is prescribed less often, primarily because of the high costs compared to aspirin.

Phenomena of 'resistance' to these drugs have been described by numerous investigators. Essentially resistance means that the effect of the drug described is less than expected or missing, as measured by various laboratory methods. We do not know which way resistance is best described, but it has been described that patients who are 'resistant' to either drug are less protected against future heart attacks or strokes.

Main objectives:

  • To measure the activity of platelets in these patients during aspirin treatment.
  • To measure the activity of platelets in a minor population of these patients during clopidogrel treatment.
  • To evaluate the prognostic significance of resistance to aspirin in these patients.


Platelet activity is measured by the PFA-100 (Dade Behring) and by traditional turbidimetric aggregation.


Myocardial infarction, unstable angina, cerebral infarction, transitory cerebral ischaemia, sudden deterioration of symptoms, percutaneous or surgical vascular intervention, amputation, death.

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 4
Study Design  ICMJE Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Condition  ICMJE Intermittent Claudication
Intervention  ICMJE Drug: Aspirin
The effect of Aspirin on platelet function was assessed.
Study Arms  ICMJE Active Comparator: Aspirin
All participants get Aspirin, and platelet reactivity measurements are performed.
Intervention: Drug: Aspirin
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: January 25, 2014)
Original Enrollment  ICMJE
 (submitted: December 6, 2005)
Actual Study Completion Date  ICMJE January 2008
Actual Primary Completion Date January 2008   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Atherosclerosis of the lower limbs, defined by one of the following criteria: Ankle-Brachial Pressure Index (ABPI)< 0.9, intermittent claudication, ischaemic pain at rest, ischaemic ulcers or gangrene.
  • Age > 18 years
  • For fertile women: Use of safe contraception (intrauterine contraceptive device, the pill, hormonal skin patches, progestogen injections, progestogen implant, vaginal ring)

Exclusion Criteria:

  • Allergy to either Aspirin or Clopidogrel
  • Known bleeding disorder
  • Platelet count < 140 mia/L or > 400 mia/L
  • Intake of NSAID's, SSRI's or Dipyridamol within the preceding 14 days
  • Not radically treated gastrointestinal ulceration within the last 6 month
  • Greater surgical procedures performed within the last 3 month
  • Severe renal disease
  • Severe hepatic disease
  • Breast feeding
  • Pregnancy
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years and older   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE Denmark
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT00262561
Other Study ID Numbers  ICMJE 2005-003844-68
Has Data Monitoring Committee Yes
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party Esben Hjorth Madsen, Aalborg University Hospital
Study Sponsor  ICMJE Aalborg University Hospital
Collaborators  ICMJE Danish Heart Foundation
Investigators  ICMJE
Principal Investigator: Nils Johannesen, MD Department of Vascular Surgery, Aalborg Hospital
PRS Account Aalborg University Hospital
Verification Date January 2014

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP