LONDON – Maintenance azithromycin may be best reserved for patients with mild to moderate chronic obstructive pulmonary disease (COPD) who also have few symptoms, according to an analysis from the COLUMBUS randomized controlled trial.
Significantly fewer exacerbations (1.06 vs. 2.62; P = .02) occurred at 1 year in patients treated with the macrolide antibiotic azithromycin rather than placebo if they were classified as having GOLD [Global Initiative for Chronic Obstructive Lung Disease] stage 1 or 2 versus stage 4.
©decade3d/Thinkstock
Study participants who were classified as being part of GOLD group C (which includes patients with a high risk of COPD exacerbation but a low level of COPD symptoms) who were treated with maintenance azithromycin were also more likely to have fewer exacerbations at 1 year, compared with patients classified as being part of GOLD group D (which includes patients with a high risk of COPD exacerbation and a high level of COPD symptoms), who took the same antibiotic (0.45 vs. 2.18; P less than .01).
Having a high serum eosinophil level (2% or higher) was a third factor found in COPD patients that was predictive of fewer exacerbations following azithromycin use (1.26 vs. 2.5; P = .02).
“Azithromycin maintenance therapy should not be given to every COPD patient,” Remco Djamin, MD, of Amphia Hospital Breda in the Netherlands said in an interview at the annual congress of the European Respiratory Society. There is, of course, the concern over antibiotic resistance developing and macrolide antibiotic use has been linked with heart problems such as arrhythmia.
These data show, however, that there are certain predictors that might help clinicians decide if long-term antibiotic therapy might be beneficial for their patients who are experiencing frequent acute exacerbations of COPD.
Further research should look at the dosing and duration of azithromycin, Dr. Djamin suggested. Perhaps reducing the dose by half to 250 mg three times per week would be just as good; maybe 6 months’ rather than 12 months’ treatment would be sufficient, or perhaps it could be given intermittently. The aim is to ensure that patients are not being exposed unnecessarily, as there is concern over antibiotic resistance.
The use of azithromycin is not currently recommended in guidelines for COPD management to prevent exacerbations, but it is something that is likely to be added to the guidelines, as the evidence for its benefit mounts, Dr. Djamin said.
In addition to COLUMBUS, there have been at least two other studies looking at long-term antibiotic use to prevent exacerbations in patients with COPD. One (Am J Respir Crit Care Med. 2008;178:1139-47) showed erythromycin could decrease the exacerbation rate at 1 year by 36%, compared with placebo, while the other (N Engl J Med. 2011;365:689-8) again showed a benefit for azithromycin, with a 27% decrease in the 1-year exacerbation rate.
In COLUMBUS, 92 patients who had experienced at least three or more acute COPD exacerbations in the previous year were randomized to treatment with azithromycin 500 mg or placebo, taken three times per week for 12 months. This was a single-center, double-blind trial conducted in the Netherlands that showed a 42% reduction in the 1-year exacerbation rate could be achieved with the antibiotic treatment (Lancet Respir Med. 2014;2:361-8).
An additional benefit to using the antibiotic was seen in patients with GOLD stage 1-2 over patients with GOLD stage 4 and in patients with a higher percentage of serum eosinophils. The GOLD stage 1-2 patients experienced fewer exacerbations leading to hospitalization, compared with patients with GOLD stage 4 (0.31 vs. 1.00; P = .04), while the patients with higher levels of eosinophils experienced fewer exacerbations requiring hospitalization than those patients with lower percentages of eosinophils (0.26 vs. 1.07; P = 0.01).
“What you should consider is that this is a group of patients who have frequent exacerbations, and most of these exacerbations are caused by infections,” Dr. Djamin said, during a poster presentation at the conference. “Their exacerbations are often already being treated with antibiotics and so maintaining treatment has become one possible way of perhaps preventing exacerbations in the future.”
The study received no industry funding. Dr. Djamin had no competing interests to disclose.