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Downstream Molecular Signals of P2Y12 Receptors in Hyporeactive Patients Under Clopidogrel Treatment A Possible Mechanism of HOTPR(High On-Treatment Platelet Reactivity)

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ClinicalTrials.gov Identifier: NCT03190005
Recruitment Status : Recruiting
First Posted : June 16, 2017
Last Update Posted : November 6, 2017
Sponsor:
Information provided by (Responsible Party):
Yueh-Chung, Chen, Taipei City Hospital

Brief Summary:
The investigators designed the following experiment to observe the pattern of administration in vitro, which can be completely excluded liver enzyme cytochrome P450 metabolism under the influence and observe the relevant P2Y12 receptor downstream signal changes, hope in the above experiments, that the human body directly for the difference between the existence of drug reactions exist.

Condition or disease Intervention/treatment Phase
Stable Angina Drug: clopidogrel Drug: Placebos Not Applicable

Detailed Description:

Platelet reactivity has been accepted as an indicator of the reaction of the P2Y12 inhibitor during treatment, currently, the existing evidence to support the post-treatment platelet activity can be used to distinguish the potential risk among patients who received percutaneous transluminal coronary angioplasty after ischemic / thrombotic events. The risks of stent thrombosis, of which, by analysis of the PRU (P2Y12 reaction units) value level of VerifyNow System has been considered an international standard tools. PRU value by VerifyNow system can easily and quickly showed platelet reactivity relative to short or long term risk stratification under dual antiplatelet agents(aspirin and clopidogrel) after stents implantation. High PRU response units (drug poor responders) in accordance with the 2013 publication of the European Society of Cardiology guidelines defined of platelet function, is PRU not less than 208(≥208).

The investigators ran a previous related plan within 2014 under the medical study project budget of the Taipei City hospital, which named "platelet reactivity as a post-percutaneous coronary stent implantation antiplatelet adjust the reference", it has been figured that responsibility under the P2Y12 receptor inhibitors were significantly different between the taiwanese and Caucasians (taiwanese revealed clopidogrel lower responsive, but stronger reaction to ticagrelor), although "low" response to clopidogrel between taiwanese (In fact, according to our experiments, 30 days after medication, the rate of HOTPR-High On- Treatment Platelet Reactivity; namely PRU≥208, the taiwanese and Caucasians are very close to each), but it has relative lower subacute stent thrombosis rate than the Caucasian at 30 days(This reaction is also known as the "Asian paradox" ), according to literature known abroad because of the high prevalence of CYP2C19 point gene deletion rate among the Asians (compare with Caucasians: ~ 65% vs ~ 30%); there also suggested other possible explanations: Caucasian factor V Leiden (G1691A) and prothrombin (G20210A) a higher proportion of mutations, on hemostatic factors (fibrinogen, d-dimer, and factor VIII) and plasma endothelial activation markers (such as von Willebrand factor, intercellular adhesion molecule 1, and E-selectin) existed differences between the races; in addition, a number of different indicators of inflammation, such as CRP. Asians show lower level CRP than the Caucasians. However, did the investigators found the true answer? So, the investigators designed the following experiment, through the mode of drug administration in vitro, can completely exclude the influence of the liver metabolic enzyme cytochrome P450, and observe the relevant downstream signals of P2Y12 receptors. The investigators believed through the current study, the internal differences in drug responsibility can be clarified.


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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 35 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: PRU after DAPT
Masking: Single (Care Provider)
Primary Purpose: Basic Science
Official Title: Downstream Molecular Signals of P2Y12 Receptors in Hyporeactive Patients Under Clopidogrel Treatment (A Possible Mechanism of HOTPR:High On- Treatment Platelet Reactivity)
Actual Study Start Date : January 1, 2017
Estimated Primary Completion Date : December 31, 2017
Estimated Study Completion Date : December 31, 2017

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Placebo Comparator: group 1
placebo control without medication.
Drug: Placebos
no medication, healthy subjects.

Experimental: group 2
hyper-reactive responser after clopidogrel.
Drug: clopidogrel
routine Dual antiplatelet therapy after stent implantation, then check PRU(platelet reactivity unit)

Experimental: group 3
hypo-reactive responser after clopidogrel.
Drug: clopidogrel
routine Dual antiplatelet therapy after stent implantation, then check PRU(platelet reactivity unit)

Experimental: group 4
normo-reactive responser after clopidogrel.
Drug: clopidogrel
routine Dual antiplatelet therapy after stent implantation, then check PRU(platelet reactivity unit)




Primary Outcome Measures :
  1. PRU(Platelet Rreactivity Unit) 24 hours after DAPT(Dual AntiPlatelet Therapy) [ Time Frame: 24 hours ]
    PRU(Platelet Rreactivity Unit) 24 hours after DAPT(Dual AntiPlatelet Therapy)



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Ages Eligible for Study:   18 Years to 99 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • DAPT(Dual antiplatelet therapy) after regular stent implantation.

Exclusion Criteria:

  • allergy to DAPT(Dual antiplatelet therapy). major bleeding intolerance to DAPT(Dual antiplatelet therapy).

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03190005


Contacts
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Contact: Chen Yueh Chung, chief doctor 886227093600 ext 3741 chenyuehchung.tw@yahoo.com.tw

Locations
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Taiwan
Taipei city hospital Recruiting
Taipei, Taiwan
Contact: Chen Yueh Chung, chief doctor    886227093600 ext 3741    chenyuehchung.tw@yahoo.com.tw   
Sponsors and Collaborators
Taipei City Hospital

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Responsible Party: Yueh-Chung, Chen, Principal Investigator, Taipei City Hospital
ClinicalTrials.gov Identifier: NCT03190005     History of Changes
Other Study ID Numbers: TCHIRB-10603117-E
First Posted: June 16, 2017    Key Record Dates
Last Update Posted: November 6, 2017
Last Verified: June 2017

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Yueh-Chung, Chen, Taipei City Hospital:
PRU
P2Y12 receptor

Additional relevant MeSH terms:
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Angina, Stable
Angina Pectoris
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Vascular Diseases
Chest Pain
Pain
Neurologic Manifestations
Signs and Symptoms
Clopidogrel
Platelet Aggregation Inhibitors
Purinergic P2Y Receptor Antagonists
Purinergic P2 Receptor Antagonists
Purinergic Antagonists
Purinergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs