This randomised, double-blind placebo control trial from New Zealand looked at the use of azithromycin in non-cystic fibrosis bronchiectasis and aimed to assess its effect on exacerbation frequency, lung function and health-related quality of life.

The trial enrolled 141 participants and randomly assigned them to receive either azithromycin 500 mg three times a week for 6 months, or placebo, with a follow up period of 1 year. Groups were well matched in terms of baseline characteristics. The co-primary endpoints were rate of exacerbations, change in forced expiratory volume in 1 s (FEV1) and change in total score on a St Georges Respiratory questionnaire (SGRQ).

The azithromycin group experienced a statistically significant decrease in the rate of exacerbations requiring antibiotic therapy over the treatment period (relative risk reduction 62%); this reduction was sustained over the 6 month period after cessation of treatment (relative risk reduction of 42% over 1 year). Time to first exacerbation requiring antibiotics was also significantly longer in the azithromycin arm. There was no significant change in FEV1 or SGRQ score.

Azithromycin is increasingly used in clinical practice in non-cystic fibrosis bronchiectasis and this study shows some promising results supporting its use. However, the dose of azithromycin used differs from that commonly used in UK practice. As the authors acknowledge, there was also no routine microbial resistance testing performed and macrolide resistance may ultimately impact on azithromycin's usefulness in the long-term. Further research is needed before azithromycin could be confidently considered a routine therapy advocated for use in non-cystic fibrosis bronchiectasis.