Roxithromycin for Non-Q wave Coronary Syndromes

Deb Bynum, MD

September 22, 1997 

Clinical Bottom Line: Patients with unstable angina or non-Q wave MI randomized to roxithromycin, a macrolide antibiotic with antichlamydial activity, had a significant reduction in the combined outcome of recurrent angina, acute MI, or death compared to similar patients who received placebo. 

The Evidence: Double blind, randomised, multicenter, placebo-controlled study of 202 patients with unstable angina or non-Qwave MI in which patients were randomised to receive roxithromycin BID or placebo in addition to standard care for their underlying ischemic disease.

Comments:

1. The study is limited secondary to small size -- although trends for a decrease in angina, MI, and death were seen in the roxithromycin group, the p value was not significant for any of these individual endpoints and only reached statistical significance when all endpoints were combined as the "triple endpoint".

2. In addition to small size, there was a significant drop-out in both groups (40%) -- the authors did attempt to show that the outcome was not changed by providing both intention to treat data as well as efficacy data.

3. The follow-up was short (30 days) and the longer intended follow-up is not known.

4. The hypothesis is that chlamydia infection may be an underlying etiology for ischemic heart disease-- we do not know if the results seen are due to antimicrobial effect or due to some other as of yet unknown effect of the drug (and some would argue that the mechanism should not matter to the clinician!)

5. Despite the shortcomings of the study, the relative risks seem to be small for the possible benefit -- for the combined endpoint of recurrent angina, acute MI or death, the absolute risk reduction was 7.1 % for a Number Needed to Treat of 14!

Source: Lancet 1997; 350: 404-07.