PACT (Platelet Activity After Clopidogrel Termination)
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 15
- 试验地点
- 1
- 主要终点
- Change From Baseline in Platelet Surface Activated GPIIb-IIIa Complex at 45 Days After Intervention.
研究概览
简要总结
Clopidogrel is a medication that is used to decrease the ability of platelets to form blood clots.
The theory has been proposed that, in patients with coronary artery disease or stroke, increased platelet function after discontinuation of clopidogrel therapy is associated with an increased clotting risk. However, this theory has never been rigorously tested.
The goal of this research is to determine whether discontinuation of clopidogrel results in increased platelet function.
详细描述
In this study, we will address the question: does discontinuation of clopidogrel result in platelet hyperreactivity? We will perform a double-blind, placebo-controlled, crossover study in normal subjects, in whom platelet reactivity will be measured before clopidogrel or placebo, during clopidogrel or placebo, and at various time points after discontinuation of clopidogrel or placebo. The dose of clopidogrel will be the standard, FDA-approved dose: 75 mg daily. All subjects will be treated with aspirin 81 mg daily throughout the 57 days of study assessment in both the clopidogrel arm and the placebo arm, because the clinically relevant question is: in patients who remain on aspirin, does discontinuation of clopidogrel result in platelet hyperreactivity?
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 21 Years 至 70 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Must be a normal healthy subject
- •Must be between 21-70 years old
- •Must be able to take aspirin and clopidogrel.
- •Must be able to have blood drawn 16 times over approximately 3 months.
排除标准
- •Subject who is currently taking aspirin or another anti-platelet drug such as clopidogrel. Subject must be free of these medications for 10 days before enrolling in this study.
- •Subject who is currently taking a non-steroidal anti-inflammatory drug such as ibuprofen or naproxen. Subject must be free of these medications for 3 days before enrolling in this study.
- •Subject who is currently taking medications for depression or medications that lower blood pressure or lower blood sugar.
- •Subject who are pregnant or may become pregnant during the study or who is breast feeding.
- •Subject with a known allergy to aspirin or clopidogrel.
- •Cigarette smoking or use of other nicotine product.
- •Subject with a history of any of the following: coronary artery disease; stroke; bleeding disorder; ongoing bleeding; previous life-threatening hemorrhage; stomach ulcers; gastrointestinal bleeding within the past 1 month; major surgery within the past 1 month; minor surgery within the past 2 weeks; or platelet transfusion within the past 7 days.
- •Subject with a blood count, measured on the pre-study drug blood sample, that is not in the normal range.
- •Subject who is enrolled in another clinical trial of an investigational drug.
研究组 & 干预措施
Clopidogrel + aspirin
The subjects will be randomized to clopidogrel 75 mg plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., clopidogrel) will then be discontinued and aspirin continued for another 43 days.
干预措施: clopidogrel + aspirin (Drug)
Clopidogrel + aspirin
The subjects will be randomized to clopidogrel 75 mg plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., clopidogrel) will then be discontinued and aspirin continued for another 43 days.
干预措施: Aspirin (Drug)
Placebo + aspirin
The subjects will be randomized to placebo plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., placebo) will then be discontinued and aspirin continued for another 43 days.
干预措施: placebo (Drug)
Placebo + aspirin
The subjects will be randomized to placebo plus aspirin 81 mg orally daily for 14 days. The study drug (i.e., placebo) will then be discontinued and aspirin continued for another 43 days.
干预措施: Aspirin (Drug)
结局指标
主要结局
Change From Baseline in Platelet Surface Activated GPIIb-IIIa Complex at 45 Days After Intervention.
时间窗: Baseline and 45 days after intervention
Value at 45 days after intervention minus value at baseline in platelet surface activated GPIIb-IIIa complex using flow cytometry.The types and concentrations of agonists used in the flow cytometry assays reported here were: ADP 0.5, 1, and 20 µmol/L; thrombin receptor activating peptide (TRAP) 1 and 20 µmol/L; and a combination of collagen 5 µg/mL and epinephrine 5 µmol/L. Mean Florescence Intensity (MFI) is used as unit of measure. MFI indicates relative degree of shift in fluorescence intensity of a population of platelets in arbitrary units.
次要结局
未报告次要终点