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NCT00646906 · ClinicalTrials.gov registry record · NA

Mechanisms of Action of Acetaminophen

A NA study of Myocardial Infarction and Arthritis, sponsored by University of Pennsylvania.

Completed
Registry status
NA
Development phase
55
Enrollment target
1
Study location

NCT00646906: Completed NA study of Myocardial Infarction and Arthritis, sponsored by University of Pennsylvania.

NCT00646906 is a NA study of Myocardial Infarction and Arthritis that has completed, run by University of Pennsylvania. The registered enrollment target is 55 participants, below the 4,681-participant average among 64 other Myocardial Infarction trials with a reported enrollment target (99% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT00646906, a NA study of Myocardial Infarction and Arthritis, has completed, sponsored by University of Pennsylvania.

COMPLETED
Registry status
NA
Development phase
55 participants
Enrollment target
1
Study location

Study Summary

This research study investigates whether the ability of aspirin to reduce the risk of heart attacks may be diminished by the administration of acetaminophen. Patients who have heart disease are often prescribed aspirin because of its unique ability to permanently prevent platelets from aggregating and forming a blood clot. Such blood clots cause heart attacks when they form in a blood vessel that supplies the heart with oxygen rich blood. Some of these same patients also take acetaminophen everyday for relief from arthritis pain. Higher doses of acetaminophen may also have the ability to prevent the platelets from clotting, however only temporarily. Therefore, this study evaluates whether the timing of the administration of acetaminophen (before or after aspirin) interferes with the permanent blood clotting effects of aspirin. The primary hypothesis is that acetaminophen given two hours before aspirin will antagonize the effects of aspirin, while reversing the order of administration will not.

Primary Outcome

Thromboxan B2 is a stable metabolite of thromboxane A2. Thromboxane B2 formation during clotting of whole blood (37 degrees Celsius, 1 hour) is reflective of the capacity of platelets to form thromboxane A2. Serum Thromboxane B2 was measured by radio-immuno assay. The quantity of interest was percent change from start (8:00 am on day 1) to finish (8:00 am on last day) of each crossover period in serum thromboxane B2. This was calculated as: 100%\*(value at start of period minus value at end of p

Interventions

  • DRUG Aspirin First
  • DRUG Aspirin Last
  • DRUG Acetaminophen 1000 mg/d
  • DRUG Acetaminophen 4000 mg/d
  • DRUG Ibuprofen 800 mg/d

Study Locations (1)

Pennsylvania

  • Hospital of The University of Pennsylvania - Philadelphia

Trial Details

FieldValue
Enrollment Target 55 participants
Start Date 2004-06-02
Est. Completion 2012-01-24
Phase NA
University of Pennsylvania

1,423 total trials

What the finished NCT00646906 record still lists

NCT00646906 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 55 participants, a relatively small participant target, below the 4,681-participant average among 64 other Myocardial Infarction trials with a reported enrollment target (99% lower).

The record links to 2 conditions, with Myocardial Infarction appearing as the primary indexed condition, and to 5 interventions - of which Aspirin First is the first listed.

NCT00646906 reports a single indexed study location in Pennsylvania.

Frequently Asked Questions

What is clinical trial NCT00646906 about?

NCT00646906 is a clinical study titled "Mechanisms of Action of Acetaminophen". This research study investigates whether the ability of aspirin to reduce the risk of heart attacks may be diminished by the administration of acetaminophen. Patients who have heart disease are often prescribed aspirin because of its unique ability to permanently prevent platelets from aggregating a...

What is the current status of trial NCT00646906?

This trial is currently completed. It is a NA study. The enrollment target is 55 participants. The study started on 2004-06-02. Estimated completion is 2012-01-24.

What conditions does trial NCT00646906 study?

This clinical trial studies the following conditions: Myocardial Infarction, Arthritis.

What interventions are being tested in trial NCT00646906?

The interventions under investigation include: Aspirin First (DRUG), Aspirin Last (DRUG), Acetaminophen 1000 mg/d (DRUG), Acetaminophen 4000 mg/d (DRUG), Ibuprofen 800 mg/d (DRUG).

Who is sponsoring clinical trial NCT00646906?

This trial is sponsored by University of Pennsylvania, which has 1,423 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT00646906 being conducted?

This trial has 1 study location across Pennsylvania. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Myocardial Infarction

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT00646906's enrollment target sits among peer trials

55 57th of 64 higher than 8 of 64 other Myocardial Infarction trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Myocardial Infarction trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT00646906, the US trial registry maintained by the National Library of Medicine. NCT00646906 (small enrollment · single site footprint · completed) retrieved and formatted by PlainTrial, see methodology.