Mechanisms fo Clopidogrel Resistance in Older Adults (CEPAGE)
France37 participantsStarted 2021-07-12
Plain-language summary
A clopidogrel resistance rate of 40-50% has been found in the population over 70 years of age, whereas biological resistance, associated with an increased risk of cardiovascular events, is observed in about 20-30% of younger patients. One hypothesis is that the active metabolite is less available in resistant patients. Indeed, 85% of the absorbed clopidogrel undergoes inactivation by esterases. Then the remaining fraction undergoes two steps of metabolisation to the active thiol metabolite by CYP450, essentially the isoform 2C19. In older adults, increased esterase activity and/or decreased CYP450 2C19 activity may lead to a decreased concentration of the active metabolite. Multiple chronic conditions and polypharmacy encountered in older individuals are associated with basal platelet hyperactivity, and may also contribute to a poor response to clopidogrel. No data on the relationship between platelet response and circulating metabolite levels, or on the determinants of response to clopidogrel, are currently available in the geriatric population. Therefore, we propose to analyse the relationship between age and platelet and extra-platelet mechanisms potentially involved in the variability of response to clopidogrel.
Who can participate
Age range
50 Years – 100 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
Consecutive patients per 10-year age range, (20 patients per age range from 50 to 100 years included) :
* in consultation or hospitalization in one of the participating centres,
* treatment with clopidogrel 75 mg/d for at least 10 days for primary or secondary prevention of cardiovascular events.
* who have received the information and have not expressed their opposition to participate in the study and who have given their written consent for the performance of genetic examinations and the realization of a biocollection
* affiliated to French social security system
Exclusion criteria :
* treatment with another antithrombotic agent,
* myeloproliferative syndrome,
* platelet count \< 100 G/L,
* acute inflammatory situation: severe sepsis, documented acute infection, chronic systemic inflammatory disease or active cancer,
* under dialysis,
* no participation in another clinical study,
* deprived of liberty
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
PK/PD correlation - clopidogrel active metabolite concentration (pharmacokinetics PK in ) / platelet response phenotype(pharmacodynamics, PD)