Trial of roxithromycin in subjects with asthma and serological evidence of infection with Chlamydia pneumoniae.

Antibiotics, Macrolide
Asthma
Chlamydophila Infections
Chlamydophila pneumoniae
Pneumonia, Bacterial
Roxithromycin
Adult
Antibodies, Bacterial
Chronic Disease
Double-Blind Method
Female
Follow-Up Studies
Forced Expiratory Volume

Human
IgG
Male
Middle Age
Peak Expiratory Flow Rate
Severity of Illness Index
Support, Non-U.S. Gov't
Time Factors
Treatment Outcome
Clinical Trial
Multicenter Study
Randomized Controlled Trial

Abstract
An association has been reported between chronic infection with Chlamydia pneumoniae and the severity of asthma, and uncontrolled observations have suggested that treatment with antibiotics active against C. pneumoniae leads to an improvement in asthma control.  We studied the effect of roxithromycin in subjects with asthma and immunoglobulin G (IgG) antibodies to C. pneumoniae > or = 1:64 and/or IgA antibodies > or = 1:16.  A total of 232 subjects, from Australia, New Zealand, Italy, or Argentina, were randomized to 6 wk of treatment with roxithromycin 150 mg twice a day or placebo.  At the end of 6 wk, the increase from baseline in evening peak expiratory flow (PEF) was 15 L/min with roxithromycin and 3 L/min with placebo (p = 0.02).  With morning PEF, the increase was 14 L/min with roxithromycin and 8 L/min with placebo (NS).  In the Australasian population, the increase in morning PEF was 18 L/min and 4 L/min, respectively (p = 0.04).  At 3 mo and 6 mo after the end of treatment, differences between the two groups were smaller and not significant.  Six weeks of treatment with roxithromycin led to improvements in asthma control but the benefit was not sustained.  Further studies are necessary to determine whether the lack of sustained benefit is due to failure to eradicate C. pneumoniae.
Comment in: Am J Respir Crit Care Med. 2001 Aug 15;164(4):513-4

Auckland Hospital
Auckland
New Zealand. pn.black@auckland.ac.nz