Validation of an Ex Vivo Cyclooxygenase-1 Catalytic Assay in Humans
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 64
- 试验地点
- 2
- 主要终点
- A Reference Range in Normal Volunteers Taking a Routine Clinical Dose of Aspirin (81mg Daily) for 2 Weeks
研究概览
简要总结
The purpose of this study is to obtain a reference range for a newly developed assay of ex vivo platelet COX-1 activity in normal volunteers taking a routine clinical dose of aspirin.
详细描述
Aspirin has been shown to reduce cardiovascular events in at-risk individuals, but some aspirin-treated patients fail to exhibit expected changes in bleeding time and platelet aggregation. Recent evidence has correlated aspirin "non-response" to poor cardiovascular outcomes.
In order to study the mechanisms of aspirin resistance, an assay is needed to measure the catalytic activity of platelet cyclooxygenase (which should be inhibited by aspirin). A common assay in general use is the measurement of thromboxane B2 production in clotting whole blood. This measure, however, is influenced by genetic and environmental variations in the glass-activated coagulation pathway, albumin binding capacity, platelet activation pathways, arachidonic acid pools, and phospholipase activity.
Our laboratory has developed a direct assay of platelet cyclooxygenase (COX-1) activity that is not influenced by these variations. This study will generate a reference range in normal volunteers taking a routine clinical dose of aspirin (81mg daily) for this assay.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Non-smoker
- •No chronic medical illness
- •No chronic medications
排除标准
- •Aspirin/NSAID use in preceding 14 days
- •History of chronic NSAID use
- •Currently taking NSAIDs, opioid analgesics, corticosteroids, or anticoagulants
- •History of coronary artery disease, myocardial infarction, coronary artery bypass grafting, percutaneous angioplasty, diabetes mellitus, or stroke.
- •History of hypertension
- •Body mass index > 35
- •History of gastric, duodenal, or esophageal ulcers or serious gastrointestinal bleed
- •History of frequent headaches, pain syndrome, or other condition requiring frequent use of analgesics
- •History of adverse reactions to aspirin
- •Screening platelet count < 100,000/ul or > 500,000/ul
- •Screening hematocrit < 35% or > 50%
- •Weight less than 110 pounds
- •Pregnant females
研究组 & 干预措施
Chewable aspirin
81 mg daily for 2 weeks
干预措施: Chewable aspirin (Other)
结局指标
主要结局
A Reference Range in Normal Volunteers Taking a Routine Clinical Dose of Aspirin (81mg Daily) for 2 Weeks
时间窗: 2 weeks
Determine the level of Thromboxane B2 at which patients with a result above are not fully inhibited, and patients with a TxB2 level below are fully inhibited. The reference range is the level of serum thromboxane at which participants below have fully inhibited COX-1 and participants above do not have fully inhibited COX-1 activity
次要结局
- Serum Thromboxane(Baseline and at 2 weeks)
研究者
John Oates
Professor of Medicine and Pharmacology
Vanderbilt University