Validation of an Assay to Measure Cyclooxygenase-1 Activity

NCT ID: NCT00761891

Last Updated: 2019-04-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 64 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2007-05-31
• Study Completion Date: 2010-01-31

Brief Summary

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.

Detailed Description

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.

Conditions

Healthy

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Chewable aspirin

81 mg daily for 2 weeks

Group Type: EXPERIMENTAL

Chewable aspirin

Intervention Type: OTHER

chewable aspirin 81mg daily for 2 weeks

Interventions

Chewable aspirin

chewable aspirin 81mg daily for 2 weeks

Intervention Type: OTHER

Other Intervention Names

acetylsalicylic acid

Eligibility Criteria

Inclusion Criteria

• Non-smoker
• No chronic medical illness
• No chronic medications

Exclusion Criteria

• 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

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Vanderbilt University

OTHER

Sponsor Role: lead

Responsible Party

John Oates

Professor of Medicine and Pharmacology

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

John A Oates, MD

Role: PRINCIPAL_INVESTIGATOR

Vanderbilt University

Locations

Vanderbilt University

Nashville, Tennessee, United States

Countries

United States

Other Identifiers

061190

Identifier Type: -

Identifier Source: org_study_id