Coronary Artery DiseasePhase 4NCT00433784
H2 Haplotype and CYP3As Polymorphisms and the Antiplatelet Response to Clopidogrel
A Phase 4 study testing Clopidogrel, Blood sampling - platelet aggregation and Blood sampling - genotyping in people with Coronary Artery Disease and Elective Percutaneous Coronary Intervention, run by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal at 1 site in Canada.
Trial summary
The purpose of this study was to assess whether interpatient variability in the platelet response to clopidogrel is partly due to polymorphisms of the hepatic cytochrome P450 (CYP450)3A and of the clopidogrel-P2Y12 receptor genes. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Coronary Artery Disease, Elective Percutaneous Coronary Intervention
- What is being tested?
- Clopidogrel, Blood sampling - platelet aggregation and Blood sampling - genotyping
- Type of treatment
- Surgery or procedure
- How many people
- 120 participants
- Where
- 1 siteCanada
- Study dates
- Sep 2004to Apr 2006
- Phase
- Phase 4
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Documented coronary artery disease (CAD) requiring an elective diagnostic coronary angiography with or without percutaneous coronary intervention (PCI)
Who cannot join
- Major bleeding disorders or active bleeding;
- Acute MI within 14 days of recruitment;
- Unstable angina with ST-segment changes of > or = 1 mm in at least two contiguous electrocardiographic leads at rest, a troponin level of > 0.06 ug/L or both within 14 days of recruitment;
- Stroke within the last 3 months;
- Platelet count < 100 x 109/L;
- Prothrombin time > 1.5 times control;
Show all 11Show fewer
- Hematocrit < 25% or hemoglobin level < 100 g/L;
- Alcohol or drug abuse;
- Enrolment in other investigational drug trials within the previous month;
- Use of thienopyridines, glycoprotein (GP) IIb/IIIa inhibitors, warfarin or acenocoumarol within the prior week;
- Allergic reaction or any contraindication to clopidogrel or aspirin.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Evaluation of the Effect of the H2 Haplotype and CYP3As Polymorphisms on the Antiplatelet Response to Clopidogrel Given Before Elective Percutaneous Coronary Intervention
The purpose of this study was to assess whether interpatient variability in the platelet response to clopidogrel is partly due to polymorphisms of the hepatic cytochrome P450 (CYP450)3A and of the clopidogrel-P2Y12 receptor genes.
Read the detailed description
Clopidogrel owes its antiplatelet effect to irreversible inhibition of the purinergic platelet receptor, P2Y12. It is estimated that approximately 4%-30% of patients treated with conventional doses of clopidogrel do not display adequate platelet response. Moreover, patients with low response to clopidogrel may be at higher risk for atherothrombotic events. Clopidogrel, being a prodrug, requires oxidation by the hepatic cytochrome P450 (CYP450)3A to generate an active metabolite.The level of CYP3A4 activity has been shown to correlate with the inhibitory effect of clopidogrel on platelet aggregation in healthy volunteers. However, CYP3As expression and activity vary among individuals. It is estimated that most of this variability is caused by individual genetic makeup.Polymorphisms of the P2Y12 receptor may also play a role in the variability in clopidogrel response. The P2Y12-H2 haplotype was associated with higher maximal platelet aggregation in response to adenosine diphosphate (ADP) as compared to the P2Y12-H1 haplotype probably due to an increase in the number of receptors on the platelet surface. It has also been suggested that carriers of the H2 haplotype might be at higher risk of developing peripheral artery disease.
Comparisons: Presence of CYP3A5 polymorphism and of the H2 haplotype compared to absence of these polymorphisms on the antiplatelet response to clopidogrel across a wide range of clopidogrel dosing regimens in patients with suspected or demonstrated coronary artery disease (CAD) scheduled to undergo elective percutaneous coronary intervention (PCI).
Platelet aggregation was measured by optical aggregometry with (ADP) 20 μmol/L as the agonist in patients before clopidogrel initiation and at the time of diagnostic coronary angiography. Genotyping was performed by standard polymerase chain reaction (PCR) method to identify expressors of CYP3A5 and P2Y12 H2 haplotype carriers.
- Being tested
- Clopidogrel, Blood sampling - platelet aggregation, Blood sampling - genotyping
- Keywords
- clopidogrel, platelet aggregation, CYP3A, H2 haplotype, polymorphisms
- Medical subject headings
- Coronary Artery Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ClopidogrelDrug
Blood sampling - platelet aggregationProcedure or surgery
Blood sampling - genotypingProcedure or surgery
What is being measured
The primary outcome is the main question the study is designed to answer.
Effect of CYP3A5 polymorphisms and of the H2 haplotype on the inhibitory effect of clopidogrel on platelet aggregation at the time of diagnostic coronary angiography as measured by optical aggregometry with adenosine diphosphate (ADP) 20 μmol/L
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Feb 2007 (estimated)
- Study startSep 2004
- Study completionApr 2006
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Coronary Artery DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Enrolment
- 120 participants
Sponsor and investigators
- Lead sponsor
- Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
- Sponsor type
- University, hospital or other
- Investigators
- Jean G Diodati, MD, Principal investigator, Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00433784
- Sponsor's protocol ID
- C.E.2004-06-24
- Status last verified
- Jun 2008
- First submitted
- 8 Feb 2007
- Last updated
- 21 Aug 2012
- Results posted
- No
Study at a glance
From the registry record, last updated by the sponsor on 21 Aug 2012. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Effect of the H2 Haplotype and CYP3As Polymorphisms on the Antiplatelet Response to Clopidogrel Given Before Elective Percutaneous Coronary Intervention
- ClinicalTrials.gov ID
- NCT00433784
- Acronym / sponsor ID
- C.E.2004-06-24
- Keywords
- clopidogrel, platelet aggregation, CYP3A, H2 haplotype, polymorphisms
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 120 participants
- Lead sponsor
- Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de MontrealUniversity, hospital or other
- Study start
- Sep 2004
- Study completion
- Apr 2006
- First posted
- 12 Feb 2007 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study was to assess whether interpatient variability in the platelet response to clopidogrel is partly due to polymorphisms of the hepatic cytochrome P450 (CYP450)3A and of the clopidogrel-P2Y12 receptor genes.
Detailed description
Clopidogrel owes its antiplatelet effect to irreversible inhibition of the purinergic platelet receptor, P2Y12. It is estimated that approximately 4%-30% of patients treated with conventional doses of clopidogrel do not display adequate platelet response. Moreover, patients with low response to clopidogrel may be at higher risk for atherothrombotic events. Clopidogrel, being a prodrug, requires oxidation by the hepatic cytochrome P450 (CYP450)3A to generate an active metabolite.The level of CYP3A4 activity has been shown to correlate with the inhibitory effect of clopidogrel on platelet aggregation in healthy volunteers. However, CYP3As expression and activity vary among individuals. It is estimated that most of this variability is caused by individual genetic makeup.Polymorphisms of the P2Y12 receptor may also play a role in the variability in clopidogrel response. The P2Y12-H2 haplotype was associated with higher maximal platelet aggregation in response to adenosine diphosphate (ADP) as compared to the P2Y12-H1 haplotype probably due to an increase in the number of receptors on the platelet surface. It has also been suggested that carriers of the H2 haplotype might be at higher risk of developing peripheral artery disease.
Comparisons: Presence of CYP3A5 polymorphism and of the H2 haplotype compared to absence of these polymorphisms on the antiplatelet response to clopidogrel across a wide range of clopidogrel dosing regimens in patients with suspected or demonstrated coronary artery disease (CAD) scheduled to undergo elective percutaneous coronary intervention (PCI).
Platelet aggregation was measured by optical aggregometry with (ADP) 20 μmol/L as the agonist in patients before clopidogrel initiation and at the time of diagnostic coronary angiography. Genotyping was performed by standard polymerase chain reaction (PCR) method to identify expressors of CYP3A5 and P2Y12 H2 haplotype carriers.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- Documented coronary artery disease (CAD) requiring an elective diagnostic coronary angiography with or without percutaneous coronary intervention (PCI)
Key exclusion criteria (11 listed)
- Major bleeding disorders or active bleeding;
- Acute MI within 14 days of recruitment;
- Unstable angina with ST-segment changes of > or = 1 mm in at least two contiguous electrocardiographic leads at rest, a troponin level of > 0.06 ug/L or both within 14 days of recruitment;
- Stroke within the last 3 months;
- Platelet count < 100 x 109/L;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Clopidogrel | Drug | – |
| Blood sampling - platelet aggregation | Procedure or surgery | – |
| Blood sampling - genotyping | Procedure or surgery | – |
Primary outcome
Effect of CYP3A5 polymorphisms and of the H2 haplotype on the inhibitory effect of clopidogrel on platelet aggregation at the time of diagnostic coronary angiography as measured by optical aggregometry with adenosine diphosphate (ADP) 20 μmol/L
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Aug 2012.
Related trials for Coronary Artery Disease
Not yet recruiting
Effect of Stress Ball Use During Femoral Arterial Sheath Removal After Coronary Angiography
Femoral Arterial Sheath Removal, Stress Ball
Active, not recruiting
Shockwave™ vs Surgical Endarterectomy for Calcified Severe Common Femoral Artery Stenosis: Comparison of Efficacy, Safety and Long-Term Outcomes
Common Femoral Artery Stenosis, Calcification; Heart
Not yet recruitingPhase 4
Roxadustat and Myocardial Injury After Off-Pump Coronary Artery Bypass Surgery
Coronary Artery Disease, Coronary Artery Bypass Grafting
RecruitingObservational study
Preoperative Gastric Ultrasound and Left Ventricular Function in Coronary Artery Bypass Surgery
Coronary Artery Disease, Left Ventricular Systolic Dysfunction
Active, not recruiting
The OCTOBER Trial - European Trial on Optical Coherence Tomography Optimized Bifurcation Event Reduction (OCTOBER)
Ischaemic Heart Disease, Ischemic Heart Disease
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jean G Diodati, MD principal investigator
Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Clopidogrel, Blood sampling - platelet aggregation and Blood sampling - genotyping in people with Coronary Artery Disease and Elective Percutaneous Coronary Intervention, run by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 21 Aug 2012. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Effect of CYP3A5 polymorphisms and of the H2 haplotype on the inhibitory effect of clopidogrel on platelet aggregation at the time of diagnostic coronary angiography as measured by optical aggregometry with adenosine diphosphate (ADP) 20 μmol/L. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Aug 2012.