Evaluation of the Biological Response to Clopidogrel in Patients With Ischemic Stroke (AAPIX)

December 30, 2015 updated by: Centre Hospitalier Universitaire de Saint Etienne

Evaluation of the Biological Response to Clopidogrel in Patients With Ischemic Stroke : Role of Platelet alpha2-adrenergic Receptors

Ischemic stroke (AIC) is the leading cause of non-traumatic disability in adults, the second leading cause of dementia and the third leading cause of death in France.

Clopidogrel is one of the recommended first line in the secondary prevention of AIC non cardioembolic origin. However recurrences occur in approximately 9% of patients receiving clopidogrel. Some studies in patients with coronary artery disease have made the connection between these treatment failures and non-biological response to clopidogrel. This non-biological response is found for approximately 30% to 50% of patients. Several mechanisms may explain this non-response. The most accepted mechanism is pharmacokinetic. Indeed, clopidogrel is a prodrug that requires intestinal absorption by P-glycoprotein (PGP) and a transformation by hepatic cytochrome into active metabolites. The genetic polymorphism of proteins involved in these two steps explain the low plasma concentration of active metabolites and thus the low efficacy of clopidogrel in some patients.

A new pharmacodynamic hypothesis suggests the involvement of platelet alpha 2-adrenergic receptors. The activation of these receptors potentiates signaling pathway P2Y12 receptor (channel inhibited by clopidogrel) and helps reduce platelet aggregation inhibiting response to clopidogrel.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Interest in the biological response to clopidogrel in the AIC is innovative because few data are available in this area. In addition to testing a new pharmacodynamic hypothesis, we also wish to study and compare other measures of platelet function methods in order to be able to use commonly in treatment decisions.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
91

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • France
      • Saint-etienne, France, 42000
        • CHU de Saint-Etienne

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Patients with non-cardioembolic AIC requiring initiation of treatment with clopidogrel as usual indications

Description

Inclusion Criteria:

  • Consent signed
  • Patients with non-cardioembolic AIC requiring initiation of treatment with clopidogrel as usual indications
  • normal standard biological tests

Exclusion Criteria:

  • Need to continue aspirin therapy
  • Patients with a recurrence of clopidogrel AIC
  • Patient already tacking clopidogrel
  • Drugs interfering with the adrenergic system alpha blockers, alpha 2 receptor agonists (alpha-methyldopa) and alpha2 receptor inhibitors (Mianserin, Mirtazapine, yohimbine)
  • Contra indication of clopidogrel and / or any of its excipients

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
AVC
Patients with non-cardioembolic AIC requiring initiation of treatment with clopidogrel as usual indications
Drug: Clopidogrel
75 mg milligrams per days of PLAVIX
Other Names:
  • PLAVIX(R)

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
adrenergic component of the platelet response
Time Frame: 5 days after taking clopidogrel
adrenergic component of the platelet response is estimated by the difference between the maximum percentage of platelet aggregation by light transmission aggregometry (LTA) with the addition of ADP(adenosine diphosphate) + ADP versus selective agonist (epinephrine)
5 days after taking clopidogrel

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
VASP-CMF
Time Frame: After 5 days taking clopidogrel
Platelet reactivity index (PRI) by VASP CMF (flow cytometry) method
After 5 days taking clopidogrel
ELISA VASP
Time Frame: After 5 days taking clopidogrel
Platelet reactivity index (PRI-ELISA) using ELISA VASP
After 5 days taking clopidogrel
active metabolite of clopidogrel
Time Frame: After 5 days taking clopidogrel
Rate of residual plasma active metabolite of clopidogrel (R-130964)
After 5 days taking clopidogrel
Genotyping of MDR-1 and P450 2C19
Time Frame: After 5 days taking clopidogrel
Genotyping of MDR-1 and P450 2C19
After 5 days taking clopidogrel

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Centre Hospitalier Universitaire de Saint Etienne

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Groupe de Recherche sur la Thrombose

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jerome VARVAT, MD, CHU de Saint-Etienne

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 1, 2013

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2015

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2015

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 27, 2013

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 4, 2013

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 7, 2013

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
December 31, 2015

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 30, 2015

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
December 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 1208094
  • 2013-000313-20 (EudraCT Number)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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