Effect of macrolides on asthma control, airway inflammation and bacterial colonisation in smokers with asthma

Asthma is a common disease in Westernised societies, affecting up to 10% of the population. Steroids are the most effective treatment for asthma but not all patients obtain benefit. A major cause of steroid insensitivity in asthma is cigarette smoking. New drugs are needed for smokers with asthma who are unable to stop smoking.

Recent cellular and animal research as well as clinical studies in non-smokers with asthma has shown that a group of antibiotics called macrolides may improve asthma control in smokers with asthma by reducing airway inflammation, by restoring steroid sensitivity and/or by anti-bacterial effects.

We plan a ?proof of concept? study to determine the benificial effects of macrolides in smokers with asthma. The study will be a 12-week controlled clinical trial comparing the oral macrolide, azithromycin with a matched placebo. A total of 80 smokers with asthma will be recruited. We will study the effects of azithromycin on lung function, symptoms,airway inflammation and number of bacterial in sputum.

This study will determine the benefits of macrolides as a new therapy for smokers with asthma.

Asthma is a common disease in Westernised societies, affecting up to 10% of the population. Corticosteroids are the most effective treatment for asthma but the therapeutic response varies considerably between individuals. A major cause of corticosteroid insensitivity in asthma is cigarette smoking. Alternative or additional drugs to corticosteroids are needed for smokers with asthma who are unable to stop smoking. Recent in vitro and animal research as well as clinical studies in non-smokers with asthma suggests that macrolides could improve asthma control in smokers with asthma by reducing airway inflammation, by restoring corticosteroid sensitivity and/or by anti-bacterial effects. In a proof of concept clinical trial we plan to investigate the efficacy of macrolide therapy in this important, but understudied clinical group. This randomised controlled trial will test the hypothesis that macrolide therapy improves asthma control of smokers with chronic asthma. In a 12-week randomised double blind parallel group study we will determine the effect on asthma control and airway inflammation of oral azithromycin therapy compared with that of a matched placebo. A total of 80 smokers with asthma will be recruited to the study. We will examine the effect of macrolide therapy on lung function, symptom scores, exacerbation rates, as well as on measurement of airway inflammation and bacterial colonisation in sputum. This study will determine the benefit of macrolides as a therapy in smokers with asthma and establish if macrolides might have a role in asthma management.