Oral azithromycin in extended dosage schedule for chronic, subclinical Chlamydia pneumoniae infection causing coronary artery disease: a probable cure in sight? Results of a controlled preliminary trial

PURPOSE: Two mega trials have raised the question as to whether the hypothesis that infection plays a role in atherosclerosis is still relevant. This controlled preliminary trial investigated an extended dose of azithromycin in the treatment of Chlamydia pneumoniae infection causing coronary artery disease (CAD). PATIENTS AND METHODS: Forty patients with documentary evidence of CAD were screened for immunoglobulin G titers against C. pneumoniae and grouped into either the study group (patients with positive titer, n = 32) or control group (patients with negative titer, n = 8). Cases who met inclusion criteria could not have had coronary artery bypass graft surgery or percutaneous coronary intervention in the preceding 6 months. Informed consent was obtained from every patient. Baseline blood samples were analyzed for red blood cell indices, serum creatinine, and liver function tests, and repeated every 2 months. A primary event was defined as the first occurrence of death by any cause, recurrent myocardial infarction, coronary revascularization procedure, or hospitalization for angina. Patients in the study group received 500 mg of oral azithromycin once daily for 5 days, which was then repeated after a gap of 10 days (total of 24 courses in the 1-year trial period). The control group did not have azithromycin added to their standard CAD treatment. RESULTS: In the study group, 30 patients completed the trial. Two patients had to undergo percutaneous coronary intervention in the initial first quarter of the 1-year trial period. In the control group, one patient died during the trial, one had to undergo coronary artery bypass graft surgery, and one had percutaneous coronary intervention. CONCLUSION: The patients tolerated the therapy well and there was a positive correlation between azithromycin and secondary prevention of CAD.