Azithromycin and Coronary Events Study (ACES)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00000617
Recruitment Status : Completed
First Posted : October 28, 1999
Last Update Posted : November 7, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
To determine whether treatment with azithromycin decreases the rate of coronary heart disease events among patients with stable documented coronary artery disease.

Condition or disease Intervention/treatment Phase
Coronary Disease Heart Diseases Myocardial Infarction Cardiovascular Diseases Drug: azithromycin Phase 3

Detailed Description:


Cumulative evidence from past studies supports but does not prove a causal association between Chlamydia pneumoniae infection and development or progression of atherosclerotic cardiovascular disease. Evidence supporting an association raises the question of whether a causal effect of Chlamydia pneumonia infection, if present, may be ameliorated by antibiotic treatment, resulting in decreased CHD outcomes. The ACES is a randomized, double-blind, placebo-controlled study to determine whether treatment with azithromycin decreases the rate of coronary heart disease events among patients with stable documented coronary artery disease.


A randomized, double-blind, multicenter trial of azithromycin versus placebo among adults with documented prevalent coronary artery disease. Patients were enrolled over an 18-month period from a total of 28 centers. Following enrollment, an electrocardiogram was obtained, and patients with a prolonged QT interval were excluded. Eligible patients were then randomized to receive either placebo or azithromycin 600 milligrams orally once a week for a year. At the time of enrollment, a blood sample was obtained for C. pneumoniae antibody testing. Patients were contacted at one, three, and six weeks, and at three, six, nine, and twelve months. The patients were followed for a mean of four years for the composite primary outcome of coronary heart disease death, non-fatal myocardial infarction, hospitalization for unstable angina, and requirement for coronary artery bypass grafting or percutaneous revascularization. After the first year of the study, each patient was contacted every six months to determine the occurrence of outcomes. In addition, when available, computerized hospitalization and outpatient data were reviewed. Outcome events were classified using standardized algorithms. The relationship of antibody titer at baseline to the efficacy of azithromycin and outcome was a secondary analysis. The primary analysis was according to the intent-to-treat principle.

In addition to the therapeutic trial a serologic follow-up substudy was conducted on 25 percent of patients enrolled in the therapeutic trial. The subset of patients were randomized to obtain blood samples at three and six months, one and two years, and at the end of the study for serologies. The purpose of the substudy was to determine the effect of azithromycin on serologic titers to C. pneumoniae and to evaluate whether the occurrence of coronary heart disease events is associated with a change in antibody titer.

Protocol planning will take place for the first six months of the trial, followed by one and a half years of patient enrollment. Patient followup continues for three years after the recruitment period and the final six months will be a close out and analysis phase.

The study completion date listed in this record was obtained from the "Completed Date" entered in the Query View Report System (QVR).

Study Type : Interventional  (Clinical Trial)
Allocation: Randomized
Masking: Double
Primary Purpose: Prevention
Study Start Date : September 1998
Actual Study Completion Date : November 2005

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U.S. FDA Resources

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Men and women over the age of 18 who have stable, documented coronary artery disease (CAD). Evidence of CAD was by any one of: history of MI; greater than 50% stenosis in any coronary artery; or history of coronary revascularization procedure.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00000617

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: J. Grayston University of Washington