Safety and Efficacy of Low-dose Ticagrelor in Chinese Patients With Stable Coronary Artery Disease

Study Overview
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Brief Summary
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Ticagrelor is an oral, reversibly-binding, direct-acting P2Y12 receptor antagonist used clinically for the prevention of atherothrombotic events in patients with acute coronary syndromes (ACS). Guideline recommendations on the use of dual antiplatelet therapy (DAPT) have been formulated that ticagrelor 90 mg twice daily plus aspirin in preference to clopidogrel 75mg daily plus aspirin for patients who have an ACS with or without ST-segment elevation. However, few East Asian patients (or those of East Asian descent) have been included in these trials to assess the use of these drugs. In Korea and Japan, it has been reported that low doses of ticagrelor might have a more potent inhibition of platelet aggregation (IPA) than clopidogrel (75 mg once daily) in healthy subjects and patients with stable coronary artery disease, respectively. But it is still not clear whether a low dose of ticagrelor is superior to clopidogrel in a large population of Chinese ACS patients. A recent study on pharmacokinetics and tolerability of ticagrelor has found that maximum plasma concentration and area under the plasma concentration-time curve of ticagrelor (90 mg twice daily) and its active metabolite (AR-C124910XX) tended to be approximately 40% higher in healthy Chinese volunteers compared with Caucasian subjects. This data also suggested that a low dose of ticagrelor might be more appropriate for Chinese ACS patients. In view of a large diurnal variation with a single daily dose, a lower dose twice daily may be a better choice for Chinese patients. Therefore, the investigators performed this randomized, single-blind, crossover clinical trial to observe the efficacy and safety of low-dose ticagrelor (22.5 mg twice daily) in comparison to clopidogrel (75mg once daily) in Chinese patients with stable coronary artery disease.

Detailed Description
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Ticagrelor is an oral, reversibly-binding, direct-acting P2Y12 receptor antagonist used clinically for the prevention of atherothrombotic events in patients with acute coronary syndromes (ACS). Guideline recommendations on the use of dual antiplatelet therapy (DAPT) have been formulated that ticagrelor 90 mg twice daily plus aspirin in preference to clopidogrel 75mg daily plus aspirin for patients who have an ACS with or without ST-segment elevation. However, few East Asian patients (or those of East Asian descent) have been included in these trials to assess the use of these drugs. In addition, a growing body of data supported that East Asian might have different adverse event profiles (thrombophilia and bleeding) and therapeutic window compared with white subjects. Furthermore, East Asian paradox phenomenon has been also described that East Asian patients have a higher prevalence of platelet reactivity during DAPT, but an ischaemic event rate following percutaneous coronary intervention (PCI) or ACS is similar or even lower than white patients. In Korea and Japan, it has been reported that low doses of ticagrelor might have a more potent inhibition of platelet aggregation (IPA) than clopidogrel (75 mg once daily) in healthy subjects and patients with stable coronary artery disease, respectively. But it is still not clear whether a low dose of ticagrelor is superior to clopidogrel in a large population of Chinese ACS patients. A recent study on pharmacokinetics and tolerability of ticagrelor has found that maximum plasma concentration and area under the plasma concentration-time curve of ticagrelor (90 mg twice daily) and its active metabolite (AR-C124910XX) tended to be approximately 40% higher in healthy Chinese volunteers compared with Caucasian subjects. This data also suggested that a low dose of ticagrelor might be more appropriate for Chinese ACS patients. In view of a large diurnal variation with a single daily dose, a lower dose twice daily may be a better choice for Chinese patients. Therefore, the investigators performed this randomized, single-blind, crossover clinical trial to observe the efficacy and safety of low-dose ticagrelor (22.5 mg twice daily) in comparison to clopidogrel (75mg once daily) in Chinese patients with stable coronary artery disease.

Official Title
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Safety and Efficacy of Low-dose Ticagrelor in Chinese Patients With Stable Coronary Artery Disease: a Randomized, Single-blind, Crossover Clinical Trial

Conditions
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Coronary Artery Disease

Intervention / Treatment
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* Drug: low-dose ticagrelor
* Drug: Clopidogrel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Stable Coronary Artery Disease stable angina low-risk unstable angina variant angina patients with asymptomatic with appropriate therapy（including percutaneous coronary intervention）. Exclusion Criteria: ACS planned use of glycoprotein IIb/IIIa receptor inhibitors, adenosine diphosphate (ADP) receptor antagonists, or anticoagulant therapy during the study period platelet count <100g/L creatinine clearance rate < 30ml/min diagnosed as respiratory or circulatory instability (cardiac shock, severe congestive heart failure NYHA II-IV or left ventricular ejection fraction < 40%) a history of bleeding tendency aspirin, ticagrelor or clopidogrel allergies diabetes.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: low-dose ticagrelor<br>To observe the safety and efficacy of low-dose ticagrelor in Chinese patients withStable Coronary Artery Disease | Drug: low-dose ticagrelor<br>* low-dose ticagrelor (22.5 mg twice daily) for 7 days,followed by a 2-week washout period then a 7days crossover phase of clopidogrel (75mg once daily)<br>* Other names: low-dose ticagrelor(22.5 mg twice daily);Drug: Clopidogrel<br>* clopidogrel (75mg once daily) for 7 days,followed by a 2-week washout period then a 7days crossover phase of low-dose ticagrelor (22.5 mg twice daily)<br>* Other names: clopidogrel (75mg once daily);|
| Active Comparator: clopidogrel<br>To observe the different safety and efficacy between low-dose ticagrelor and conventional-dose clopidogrel. | Drug: low-dose ticagrelor<br>* low-dose ticagrelor (22.5 mg twice daily) for 7 days,followed by a 2-week washout period then a 7days crossover phase of clopidogrel (75mg once daily)<br>* Other names: low-dose ticagrelor(22.5 mg twice daily);Drug: Clopidogrel<br>* clopidogrel (75mg once daily) for 7 days,followed by a 2-week washout period then a 7days crossover phase of low-dose ticagrelor (22.5 mg twice daily)<br>* Other names: clopidogrel (75mg once daily);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| P2Y12 reaction units (PRU) |  | up to 5 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| inhibition of platelet aggregation (IPA) |  | up to 5 months |