Expired Study
This study is not currently recruiting Study Participants on ClinicalConnection.com. If you would like to find active studies please search for clinical trials.

Worcester, Massachusetts 01655


Purpose:

Clopidogrel is a medication that is used to decrease the ability of platelets to form blood clots. The theory has been proposed that, in patients with coronary artery disease or stroke, increased platelet function after discontinuation of clopidogrel therapy is associated with an increased clotting risk. However, this theory has never been rigorously tested. The goal of this research is to determine whether discontinuation of clopidogrel results in increased platelet function.


Study summary:

In this study, we will address the question: does discontinuation of clopidogrel result in platelet hyperreactivity? We will perform a double-blind, placebo-controlled, crossover study in normal subjects, in whom platelet reactivity will be measured before clopidogrel or placebo, during clopidogrel or placebo, and at various time points after discontinuation of clopidogrel or placebo. The dose of clopidogrel will be the standard, FDA-approved dose: 75 mg daily. All subjects will be treated with aspirin 81 mg daily throughout the 57 days of study assessment in both the clopidogrel arm and the placebo arm, because the clinically relevant question is: in patients who remain on aspirin, does discontinuation of clopidogrel result in platelet hyperreactivity?


Criteria:

Inclusion Criteria: - Must be a normal healthy subject - Must be between 21-70 years old - Must be able to take aspirin and clopidogrel. - Must be able to have blood drawn 16 times over approximately 3 months. Exclusion Criteria: - Subject who is currently taking aspirin or another anti-platelet drug such as clopidogrel. Subject must be free of these medications for 10 days before enrolling in this study. - Subject who is currently taking a non-steroidal anti-inflammatory drug such as ibuprofen or naproxen. Subject must be free of these medications for 3 days before enrolling in this study. - Subject who is currently taking medications for depression or medications that lower blood pressure or lower blood sugar. - Subject who are pregnant or may become pregnant during the study or who is breast feeding. - Subject with a known allergy to aspirin or clopidogrel. - Cigarette smoking or use of other nicotine product. - Subject with a history of any of the following: coronary artery disease; stroke; bleeding disorder; ongoing bleeding; previous life-threatening hemorrhage; stomach ulcers; gastrointestinal bleeding within the past 1 month; major surgery within the past 1 month; minor surgery within the past 2 weeks; or platelet transfusion within the past 7 days. - Subject with a blood count, measured on the pre-study drug blood sample, that is not in the normal range. - Subject who is enrolled in another clinical trial of an investigational drug.


Study is Available At:


Original ID:

CPFS 2008-1


NCT ID:

NCT00619073


Secondary ID:


Study Acronym:

PACT


Brief Title:

PACT (Platelet Activity After Clopidogrel Termination)


Official Title:

PACT (Platelet Activity After Clopidogrel Termination)


Overall Status:

Completed


Study Phase:

N/A


Genders:

N/A


Minimum Age:

21 Years


Maximum Age:

70 Years


Quick Facts

Healthy Volunteers
Oversight Has DMC
Study Is FDA Regulated
Study Is Section 801
Has Expanded Access

Study Source:

University of Massachusetts, Worcester


Oversight Authority:

United States: Institutional Review Board


Reasons Why Stopped:


Study Type:

Interventional


Study Design:


Number of Arms:

2


Number of Groups:

0


Total Enrollment:

15


Enrollment Type:

Actual


Overall Contact Information

Official Name:Alan D. Michelson, M.D.
Principal Investigator
University of Massachusetts, Worcester

Study Dates

Start Date:April 2008
Completion Date:May 2009
Completion Type:Actual
Primary Completion Date:May 2009
Primary Completion Type:Actual
Verification Date:April 2018
Last Changed Date:April 30, 2018
First Received Date:February 6, 2008
First Results Date:January 10, 2012

Study Outcomes

Outcome Type:Primary Outcome
Measure:Change From Baseline in Platelet Surface Activated GPIIb-IIIa Complex at 45 Days After Intervention.
Time Frame:Baseline and 45 days after intervention
Safety Issues:False
Description:Value at 45 days after intervention minus value at baseline in platelet surface activated GPIIb-IIIa complex using flow cytometry.The types and concentrations of agonists used in the flow cytometry assays reported here were: ADP 0.5, 1, and 20 µmol/L; thr

Study Interventions

Intervention Type:Drug
Name:clopidogrel + aspirin
Description:Clopidogrel 75mg plus aspirin 81mg, tablet by mouth daily for 14 days.
Arm Name:Clopidogrel + aspirin
Other Name:Plavix
Intervention Type:Drug
Name:placebo
Description:Placebo plus aspirin 81 mg, tablet by mouth daily for 14 days.
Arm Name:Placebo + aspirin
Other Name:aspirin
Intervention Type:Drug
Name:Aspirin
Description:Aspirin 81mg tablet by mouth continued daily alone for 43 days after day 14.
Arm Name:Clopidogrel + aspirin

Study Arms

Study Arm Type:Active Comparator
Arm Name:Clopidogrel + aspirin
Description:The subjects will be randomized to clopidogrel 75 mg plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., clopidogrel) will then be discontinued and aspirin continued for another 43 days.
Study Arm Type:Placebo Comparator
Arm Name:Placebo + aspirin
Description:The subjects will be randomized to placebo plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., placebo) will then be discontinued and aspirin continued for another 43 days.

Study Agencies

Agency Class:Other
Agency Type:Lead Sponsor
Agency Name:University of Massachusetts, Worcester
Agency Class:Industry
Agency Type:Collaborator
Agency Name:Sanofi

Sample and Retention Information

There are no available Sample and Retention Information

Study References

Reference Type:Results Reference
Citation:Frelinger AL 3rd, Barnard MR, Fox ML, Michelson AD. The Platelet Activity After Clopidogrel Termination (PACT) study. Circ Cardiovasc Interv. 2010 Oct;3(5):442-9. doi: 10.1161/CIRCINTERVENTIONS.110.937961. Epub 2010 Aug 24.
PMID:20736449

Data Source: ClinicalTrials.gov

Date Processed: August 31, 2019

Modifications to this listing: Only selected fields are shown, please use the link below to view all information about this clinical trial.


This study is not currently recruiting Study Participants. The form below is not enabled.