Aspirin Resistance and Stroke Risk: Platelet Function Analysis in Patients With Ischemic Events

• ClinicalTrials.gov Identifier: NCT01586975
• Recruitment Status: Completed
• First Posted: April 27, 2012
• Results First Posted: December 3, 2015
• Last Update Posted: December 31, 2015
• Sponsor: Northwestern University
• Information provided by (Responsible Party): Northwestern University

Tracking Information

• First Submitted Date: August 3, 2011
• First Posted Date: April 27, 2012
• Results First Submitted Date: June 29, 2015
• Results First Posted Date: December 3, 2015
• Last Update Posted Date: December 31, 2015
• Study Start Date: July 2007
• Actual Primary Completion Date: April 2010 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: December 2, 2015)

PFA1 [ Time Frame: 3-6 months (Collected once between regulalary scheduled follow-up visit between 3-6 months) ]

Platelet Function Analysis (PFA) lab results: PFA was performed using the PFA 100 device (Dade-Behring), which uses a higher sheer stress flow cytometry paradigm to measure the time in seconds to closing of an aperture. Normal is defined as <172 seconds."

Original Primary Outcome Measures (submitted: April 26, 2012)

• PFA results correlating with ischemic events and bleeding complications [ Time Frame: 4 years ]
  Platelet Function Analysis (PFA) lab results, and P2y12 lab results
• PFA results correlating with ischemic events and bleeding complications [ Time Frame: 4 years ]
  Platelet Function Analysis (PFA) lab results, and P2y12 lab results. If there is a change in the lab results that show the chosen agent (ie aspirin or clopidogrel) is not working, then the agent will be modified.

• Change History: Complete list of historical versions of study NCT01586975 on ClinicalTrials.gov Archive Site
• Current Secondary Outcome Measures: Not Provided
• Original Secondary Outcome Measures: Not Provided
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Aspirin Resistance and Stroke Risk: Platelet Function Analysis in Patients With Ischemic Events
• Official Title: Multiphase Study to Determine if Platelet Function Analysis Results Correlate With Ischemic Events and Bleeding Complications
• Brief Summary: The purpose of this study is to determine if PFA results correlate with ischemic event outcomes as well as bleeding complications. Hypothesis is antiplatelet agents will be more efficacious if they are administered in a dose-adjusted manner using PFA results as a guide.
• Detailed Description: Atherothrombotic disease is a leading killer of adults throughout the world. The current mainstay for the prevention of ischemic vascular events is the use of aspirin Antiplatelet agents are used routinely for the primary and secondary prevention of vascular events in patients with a prior history of stroke, TIA, or at high risk for the development of cerebrovascular disease. Numberous individual studies and meta-analyses have shown that essentially all of the oral antiplatelet agents have limited efficacy, with relative risk reductions in the range of 20-35%. The purpose of this study is to perform serial platelet function assays (PFAs) on patients with cerebrovascular disease who are taking antiplatelet agents and perform a pilot study to determine the feasibility of administering ASA as a dose adjusted medication using PFA. The long term goal of this study is to determine whether antiplatelet therapy will be more efficacious and/or safer if it is administered in a dose-adjusted manner.
• Study Type: Interventional
• Study Phase: Phase 2; Phase 3
• Study Design: Allocation: Non-Randomized; Intervention Model: Parallel Assignment; Masking: None (Open Label); Primary Purpose: Treatment

Condition

• Stroke
• Myocardial Infarctions

Intervention

• Drug: Clopidogrel
  Clopidogrel 75 mg QD
  Other Name: Plavix
• Drug: Aspirin 81 mg
  Aspirin 81mg QD
  Other Names:

  • Acetylsalicylic Acid
  • ASA
• Drug: Aspirin >300 mg
  Aspirin >300 mg QD
  Other Names:

  • Acetylsalicylic Acid
  • ASA

Study Arms

• Active Comparator: Clopidogrel 75 mg
  Clopidogrel 75 mg daily
  Intervention: Drug: Clopidogrel
• Active Comparator: Aspirin 81 mg
  open-label Aspirin 81 mg daily
  Intervention: Drug: Aspirin 81 mg
• Active Comparator: Aspirin > 300mg
  open-label Aspirin over 300 mg daily
  Intervention: Drug: Aspirin >300 mg

• Publications *: Taylor TN, Davis PH, Torner JC, Holmes J, Meyer JW, Jacobson MF. Lifetime cost of stroke in the United States. Stroke. 1996 Sep;27(9):1459-66. Review.

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: October 27, 2015): 93
• Original Actual Enrollment (submitted: April 26, 2012): 133
• Actual Study Completion Date: December 2011
• Actual Primary Completion Date: April 2010 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• Patient must be taking Aspirin or Plavix
• Patient must have had a stroke, TIA or cerebrovascular disease

Exclusion Criteria:

-None

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United States

Administrative Information

• NCT Number: NCT01586975
• Other Study ID Numbers: Aspirin Resistance and Stroke; IRB#0996-007 FUND#7810 ( Other Identifier: Northwestern Memorial Hospital )
• Has Data Monitoring Committee: No
• U.S. FDA-regulated Product: Not Provided
• IPD Sharing Statement: Not Provided
• Responsible Party: Northwestern University
• Study Sponsor: Northwestern University
• Collaborators: Not Provided

Investigators

• Principal Investigator: Mark J Alberts, MD; Northwestern University

• PRS Account: Northwestern University
• Verification Date: December 2015