An interventional study of Point-of-Care CYP2C19 Testing and ticagrelor + aspirin in Intracranial Atherosclerosis, sponsored by Sunnybrook Health Sciences Centre. Recruiting at 2 sites in Canada. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2025-11-20.
Sponsored by Sunnybrook Health Sciences Centre · Not applicable, Interventional, and Treatment
Stroke is an important cause of death, disability, and memory problems in adults. The build-up of plaque in arteries inside the brain is known as "intracranial atherosclerotic disease" or "ICAD" for short, and can reduce blood flow in the brain. Clopidogrel is a medicine used to prevent strokes because it stops blood from clotting. However, there are some people who do not get as much benefit from Clopidogrel because of differences in their genes; they have a variation in a certain gene and their body is not able to properly process Clopidogrel. Another medication called Ticagrelor can benefit people who have this genetic variation. The study investigators will randomize patients who have had a stroke due to ICAD to receive genetic testing, or standard of care. The standard-of-care group will take Clopidogrel for 90 days. The genetic testing group will complete a genetic test to see if they can properly process Clopidogrel. Depending on the results of the genetic test, patients will either take Clopidogrel or Ticagrelor for 90 days. All patients will have a brain scan at baseline and 90 days to see if they had any new strokes. Patients will also complete tests and questionnaires about function and memory at baseline and 90 days. This study will be one of the first to see if it is feasible and safe to use genetic testing to help choose medications for patients who have had a stroke. This will help the study investigators design a larger study that can test if genetic testing in stroke patients reduces future stroke risk and improves health outcomes.
94 studies on the registry are indexed under Intracranial Arteriosclerosis; 42 are open to participants now.
This study's planned enrollment of 100 is below the median of 187 across 56 interventional studies indexed under Intracranial Arteriosclerosis.
Browse Intracranial Arteriosclerosis studies →Sunnybrook Health Sciences Centre is the lead sponsor of 566 studies on the registry; 133 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Patients will undergo point-of-care CYP2C19 testing with the Research Use Only (RUO) Genomadix Cube to inform the choice of P2Y12 inhibitor (i.e. clopidogrel vs ticagrelor).
Genetic: Point-of-Care CYP2C19 Testing · Drug: ticagrelor + aspirin · Drug: clopidogrel + aspirin
Patients will receive standard-of-care ASA + clopidogrel.
Genetic testing with the Genomadix cube to determine P2Y12 inhibitor
If patients are poor or intermediate metabolizers of clopidogrel, they will receive ticagrelor (90 mg PO BID) + aspirin (81 mg PO daily)
Normal, rapid, and ultra-rapid metabolizers of clopidogrel will receive 75 mg PO daily of clopidogrel and 81 mg PO daily of aspirin.
Rate of recruitment
The number of patients who provide informed consent, or are deemed ineligible after screening.
Time frame: Through study completion, an average of 90 days
Rate of study completion
The number of patients who complete the entire study protocol
Time frame: Through study completion, an average of 90 days
Rate of protocol deviations
The number of patients who encounter at least one protocol deviation during the study
Time frame: Through study completion, an average of 90 days
Proportion of patients with Symptomatic intracerebral hemorrhage (ICH)
New symptomatic ICH OR worsening existing ICH with a ≥33% increase in hematoma volume AND NIHSS score increase of ≥4 points AND clinical change is thought to be attributable to ICH
Time frame: Through study completion, an average of 90 days
Proportion of patients with major extracranial bleeding
Bleeding in a critical area or organ, including intraspinal, intraocular, retroperitoneal, intra-articular, pericardial, intramuscular with compartment syndrome, and/or bleeding causing a drop in hemoglobulin by 20g/L or more
Time frame: Through study completion, an average of 90 days
Proportion of patients with non-bleeding adverse events
Non-bleeding adverse events related to the study drug including dyspnea, bradyarrhythmia, and/or chest pain
Time frame: Through study completion, an average of 90 days
Proportion of patients who have Microembolic Signals on Transcranial Doppler Ultrasound
Time frame: Day 5 ± 2
Change in volume of ischemic strokes and white matter hyperintensities (optional)
Time frame: Day 0 + 14 and Day 90 ± 14
Change in number of ischemic strokes and white matter hyperintensities
Time frame: Day 0 + 3 and Day 90 ± 14
Number of patients with ischemic stroke, myocardial infarction, or death
Time frame: Day 90 ± 14
Change in Montreal Cognitive Assessment (MoCA) score from baseline to follow-up
To MoCA is a validated cognitive screening tool. Possible scores range from 0 (worst score) to 31 (best score). Change = Follow-up - baseline.
Time frame: Day 0 and Day 90 ± 14
Change in NIH Stroke Scale (NIHSS) score from baseline to follow-up
This scale is a 15 item tool used to quantify stroke severity. Scores range from 0 (no stroke) to 42 (most severe stroke). Change = Follow-up - baseline.
Time frame: Day 0 and Day 90 ± 14
Change or shift in modified Rankin Scale (mRS) score from baseline to follow-up
The MRS is a single item rating of stroke outcomes. Scores range from 0 (no symptoms) to 6 (death). Change = Follow-up - baseline.
Time frame: Day 0 and Day 90 ± 14
Self-reported Quality of Life as assessed by the EQ-5D-5L
The EQ-5D-5L questionnaire has 5 dimensions: Mobility, Self-Care, Usual Activity, Pain/Discomfort, Anxiety/Depression, with each dimension rated on a level from 1-5 where higher scores indicate more severe problems.
Time frame: Day 90 ± 14
Self-reported Dementia Screening assessed by the AD8 Dementia Screening Interview
The AD8 Dementia Screening Interview has 8 questions that ask if there has been a change in the last several years caused by cognitive (thinking and memory) problems. The score is the sum of all items marked "Yes, A change".
Time frame: Day 90 ± 14
Self-reported functional status assessed by the Lawton-Brody Instrumental Activities of Daily Living Scale
The Lawton-Brody Instrumental Activities of Daily Living Scale has 8 categories where participants can rate their functional level. Scores range from 0 (low function, dependent) to 8 (high function, independent).
Time frame: Day 90 ± 14
Plan to share: No
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