Decreased platelet miR-199a-5p level might lead to high on-clopidogrel platelet reactivity in patients with coronary artery disease.

What is the context?● Clopidogrel combined with aspirin is widely used in coronary artery disease (CAD) patients, while some patients exhibit high platelet activity when receiving the combined treatment.● Current environmental and genetic factors could only explain part of the variability in clopidogrel efficacy.● Human platelets harbor abundant miRNAs which might affect clopidogrel efficacy by regulating the expression of key proteins in the clopidogrel antiplatelet signaling pathway.What is new?● We found that decreased platelet miR-199a-5p level was associated with high on-clopidogrel platelet reactivity.● Overexpression of miR-199a-5p significantly down-regulated the expression of VASP protein in cultured cells.What is the impact?● The current study provided new insights into the exploration of interindividual variability in clopidogrel response from the perspective of miR-199a-5p and VASP interaction.