Understanding Clopidogrel Resistance in Older Adults

Mechanisms fo Clopidogrel Resistance in Older Adults

Observational Rennes University Hospital · NCT04990596

This study is trying to understand why some older adults don't respond well to the heart medication clopidogrel, by looking at how the drug works in their bodies and how it affects their blood platelets.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages50 Years to 100 Years
SexAll
SponsorRennes University Hospital Academic / other
Locations4 sites (Paris and 3 other locations)
Trial IDNCT04990596 on ClinicalTrials.gov

What this trial studies

This observational study aims to investigate the mechanisms behind clopidogrel resistance in older adults, particularly focusing on the pharmacokinetics and pharmacodynamics of the drug. It will assess the correlation between the concentration of clopidogrel's active metabolite and the platelet response in patients aged 50 to 100 years who are receiving clopidogrel for cardiovascular event prevention. The study will involve multiple centers and will utilize a linear regression model to analyze the data collected from blood samples and patient responses. Results will contribute to a better understanding of how age and other factors influence clopidogrel efficacy.

Who should consider this trial

Good fit: Ideal candidates are older adults aged 50 to 100 years who are hospitalized and have been on clopidogrel for at least 10 days.

Not a fit: Patients currently on other antithrombotic agents or with certain medical conditions such as myeloproliferative syndrome or active cancer may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved treatment strategies for older adults at risk of cardiovascular events by addressing clopidogrel resistance.

How similar studies have performed: While there is existing literature on clopidogrel resistance, this study's specific focus on older adults and the correlation of metabolite levels with platelet response is a novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

Paris and 3 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Drug Resistanceclopidogrelprimary or secondary prevention of cardiovascular eventsolder adultsclopidogrel resistanceDrug resistanceAntiplatelet resistance
Last reviewed 2026-06-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.