Stroke Clopidogrel – CYP2C19 Genotype Testing

What is Stroke Clopidogrel (CYP2C19) Genotype Testing? 

A national pathway for clopidogrel (CYP2C19) genotype testing is being introduced for newly presenting patients who have had a transient ischaemic attack (TIA) or an ischaemic (non-cardioembolic) stroke.    

The programme uses a genetic test to check specific variants of the CYP2C19 gene, which indicate whether clopidogrel is the most suitable antiplatelet medication for them.

This test ensures that patients receive the most effective treatment.  

What are the benefits of Stroke Clopidogrel (CYP2C19) Genotype Testing? 

The national rollout of the laboratory-based test is expected to bring various benefits for patients and the healthcare system.   

By identifying individuals who are resistant to clopidogrel, the testing could prevent 943 strokes by ensuring that all patients at risk of a secondary ischaemic stroke are prescribed the most effective antiplatelet medication. 

This targeted approach is projected to save NHS Scotland £17.9m and further analysis suggests an additional £30.6 million will be saved in social care, including avoided costs related to education. 

The demand for hospital beds is expected to decrease within five years, freeing up the equivalent of 21 beds per day helping to ease pressure on services. 

How will the tests be carried out? 

If clopidogrel is recommended as part of a patient’s stroke treatment, the stroke care team will take a small blood sample. This blood sample will be sent to a laboratory to test for specific variants in the CYP2C19 gene, which influence how well the patient can metabolise clopidogrel.   

The results of this test will inform the clinician if the patient is a poor or normal metaboliser of clopidogrel which will guide prescribing.

If the patient is a poor metaboliser they will be offered an alternative antiplatelet drug that is likely to be more effective for them.  

Please click the links for Information for Clinicians and Information for Patients.