Reducing Asthma Exacerbations, Improving Patient QoL With Azithromycin

Azithromycin significantly reduced exacerbations and improved health-related quality of life (QoL) in adults with uncontrolled asthma, according to data published in The Lancet.

Peter G. Gibson, MD, from the Hunter Medical Research Institute in New Lambton Heights, New South Wales, Australia, and colleagues sought to determine the antibacterial, antiviral, and anti-inflammatory effects of the macrolide azithromycin in adult patients with asthma exacerbations (ANZCTR number: 12609000197235).

The double-blind placebo-controlled trial randomly assigned 420 patients to thrice-weekly 500 mg azithromycin (median age: 60.01) or placebo (median age: 61.02) for 48 weeks. The primary end points were total asthma exacerbations and asthma-related QoL scores. Secondary end points included the Asthma Control Questionnaire (ACQ6) score, lung function, induced sputum cell counts, antibiotic use for respiratory infection, microbial assessments, and adverse events.

Patients included in the study had an ACQ6 score of ≥.75, were currently symptomatic despite inhaled corticosteroid or long-acting bronchodilator use, and had documented evidence of variable airflow obstruction. Patients were excluded from the study if they were current smokers, had parenchymal lung disease, or their diffusing capacity for carbon monoxide was <70% of the predicted value.

The asthma exacerbations in the azithromycin vs placebo groups were 1.07 per patient-years (95% CI, .85-1.29) and 1.86 per patient-years (95% CI, 1.54-2.18), respectively. Azithromycin use significantly improved asthma-related QoL scores compared with placebo (adjusted mean difference: 0.36; 95% CI, 0.21-0.52; P =.001).

In the secondary end points, azithromycin improved asthma control, as measured by the ACQ6 (adjusted mean difference: −0.20; 95% CI, −0.34 to −0.05). Patients who received azithromycin also had fewer nasal symptoms, cough, and sputum.

The most common adverse events in azithromycin and placebo, respectively, were diarrhea (34% vs 19%), abdominal pain (18% vs 15%), and nausea (15% vs 10%). Adverse events leading to study withdrawals were comparable in both the azithromycin group (7%) and the placebo group (5%; P =.34).

“Given the major impact of asthma exacerbations on patients and the community, and the ongoing risk posed by these events in patients who remain symptomatic on maintenance therapy, we consider that azithromycin is a valuable addition to existing regimens for treating asthma,” noted the researchers. “The long-term effects of this therapy on community microbial resistance require further evaluation.”

Study Limitations

• Using last observation carried forward analysis — one of the primary end points — may have inadvertently favored the treatment group data
• The sample size of the exacerbation group may have been inadequate to render a meaningful analysis

Disclosures

The study was funded by the National Health and Medical Research Council of Australia and the John Hunter Hospital Charitable Trust.

Reference 

Gibson PG, Yang IA, Upham JW, et al. Effect of azithromycin on asthma exacerbations and quality of life in adults with persistent uncontrolled asthma (AMAZES): a randomised, double-blind, placebo-controlled trial [published online July 4, 2017]. Lancet. doi:10.1016/S0140-6736(17)31281-3