Short TEG: cessation of clopidogrel following insertion of drug-eluting coronary stents

ISRCTN	ISRCTN51917813
DOI	https://doi.org/10.1186/ISRCTN51917813
Secondary identifying numbers	7907

Submission date: 23/04/2010
Registration date: 23/04/2010
Last edited: 22/07/2013

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Circulatory System

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr Nicholas Curzen
Scientific

Southampton General Hospital
Cardiology Research
Wessex Cardiac Unit, Mail Point 46
Southampton
SO16 6YD
United Kingdom

Study information

Study design	Randomised interventional screening clinical laboratory study
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Hospital
Study type	Screening
Participant information sheet	Not available in web format, please use the contact details below to request a patient information sheet
Scientific title	An investigation into the effects of cessation of clopidogrel therapy on vascular inflammation and platelet reactivity in patients with drug-eluting coronary stents: is there a "rebound phenomenon"?
Study objectives	The hypothesis of this trial is that cessation of clopidogrel maintenance therapy after 12 months in patients receiving drug-eluting stents is associated with a pro-inflammatory and pro-thrombotic response that offers an explanation for the observed clustering of clinical events, including stent thrombosis, that have been described in the first 90 days after clopidogrel is stopped. Antiplatelet agents (drugs used to prevent platelets from binding together and forming blood clots) are widely used in the prevention and treatment of cardiovascular disease. Aspirin and clopidogrel are essential antiplatelet drugs required in all patients undergoing percutaneous coronary intervention (PCI) where narrowed arteries are stretched open with balloons and stents to improve the blood supply to the heart. Previous studies have demonstrated a wide range of patient response to antiplatelet agents. Poor responders are at increased risk of complications including potentially fatal stent thrombosis (blood clot forming within the stent), particularly in the period immediately after cessation of clopidogrel. A large observational study has reported a clustering of events, including death and heart attacks within the first 90days of stopping clopidogrel, raising the possibility of a clopidogrel "rebound" effect. The reason for this effect is unknown and it has been proposed that it may be due to an increase in inflammatory markers and platelet activation following withdrawal of clopidogrel. The aim of our study is to investigate whether clopidogrel cessation 12 months after PCI causes a rebound proinflammatory and prothrombotic effect. We will investigate the mechanism behind this phenomenon and whether it is related to the lack of synergistic effect of clopidogrel on responses to aspirin when clopidogrel treatment is withdrawn. We will also assess whether the response differs in diabetic patients.
Ethics approval(s)	Southampton and South West Hampshire Research Ethics Committee (A) approved on the 5th November 2009 (ref: 09/H0502/106)
Health condition(s) or problem(s) studied	Topic: Cardiovascular; Subtopic: Cardiovascular (all Subtopics); Disease: Cardiovascular
Intervention	Patients are not randomised to any treatment in this trial. All enrolled patients are due to stop dual antiplatelet medication as part of their routine care. This study is assessing the effects of stopping clopidogrel at the end of a routine 12 months course of treatment. Patients are followed up in the study for approximately 7 weeks attending the hospital for 7 blood tests over that time.
Intervention type	Other
Primary outcome measure	Clopidogrel is routinely used for 12 months after drugeluting stent implantation
Secondary outcome measures	Any differences in inflammatory markers, measured at 12 months
Overall study start date	01/01/2010
Completion date	01/11/2010

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	Both
Target number of participants	Planned Sample Size: 60
Key inclusion criteria	1. Aged greater than 18 years, either sex 2. Signed written informed consent 3. Prior percutaneous coronary intervention (PCI) with drugeluting stent implantation and due to stop clopidogrel 12 months after PCI 4. On maintenance dose aspirin 75 mg and clopidogrel 75 mg daily 5. 30 diabetics and 30 nondiabetics
Key exclusion criteria	1. Aged greater than 85 years 2. On regular nonsteroidal antiinflammatory medication or steroids
Date of first enrolment	01/01/2010
Date of final enrolment	01/11/2010

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

Southampton General Hospital

Southampton
SO16 6YD
United Kingdom

Sponsor information

Southampton University Hospitals NHS Trust (UK)
Hospital/treatment centre

MRC Environmental Epidemiology Unit
Tremona Road
Southampton
SO16 6YD
England
United Kingdom

Website	http://www.suht.nhs.uk/home.aspx
"ROR"	https://ror.org/0485axj58

Funders

Funder type

Industry

Haemonetics Limited (UK)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results	01/10/2011		Yes	No