Roxithromycin in Non-Q-Wave MI

Substantial circumstantial evidence implicates Chlamydia pneumoniae in sequelae of coronary artery disease. High titers of C. pneumoniae antibody correlate with coronary heart disease, and atherosclerotic plaques themselves may demonstrate the organism. There is some suggestion that C. pneumoniae affects plaque stability, as well as atherogenesis.

The authors tested the hypothesis that treatment with an anti-chlamydial antibiotic would reduce clinical end points in patients with unstable angina and non-Q-wave MI. In a double-blind, randomized, placebo-controlled pilot study, 202 patients were assigned either roxithromycin or placebo, in addition to conventional therapy. Roxithromycin (U.S. trade name Dynabac) is similar to azithromycin (Zithromax) and clarithromycin (Biaxin) and is the most widely prescribed non-erythromycin macrolide in a number of European nations. Treatment, which included heparin and aspirin, was continued for 30 days, and follow-up continued for six months.

The primary composite triple end point (rate of severe recurrent ischemia, MI, and ischemic death) was substantially lower in the treatment group (1.1%, 0%, 0%) than in the placebo group (5.4%, 2.2%, 2.2%; P < 0.05).

There were no serious drug-related adverse events. The mechanism by which roxithromycin exerts its effects remains speculative, but possible suppression of chronic C. pneumoniae infection within atherosclerotic plaque, or independent anti-inflammatory activity of the drug may play a role.

Gurfinkel E, et al. Lancet 1997;350: 404-407.