Azithromycin to remodel airways in patients with severe persistent asthma, study finds

Iran: A recent study in the journal Respiratory Medicine has reported that azithromycin increases bronchial lumen area and lumen radius in patients with severe asthma. Azithromycin, however, did not reduce the bronchial wall thickness. 

Azithromycin is an antibiotic used to treat many bacterial and respiratory infections. Recent animal studies showed azithromycin is capable of reducing airway remodeling. However, its effect on human subjects has not been studied yet. Mohammadamin Sadeghdoust, Shiraz University of Medical Sciences, Shiraz, Iran, and colleagues aimed to investigate the effect of long-term treatment with azithromycin on airways wall thickness in patients with severe persistent asthma. 

The study was designed as a randomized, double-blinded, placebo-controlled clinical trial involving patients with severe persistent asthma. They were given azithromycin (250 mg, BID, three days a week), prednisolone (5 mg, BID), or a placebo for eight months in three separate groups in addition to the standard therapy. The improvement in right upper lobe apical segmental bronchus (RB1) wall thickness obtained by high resolution computed tomography was set as the primary outcome. Secondary outcomes included: cough severity, dyspnea severity, asthma control test (ACT) score, asthma exacerbation rate, pulmonary function tests, and fractional exhaled nitric oxide (FENO).

The results of the study were found to be

• A total of seventy-eight out of ninety randomized subjects completed eight months of treatment with azithromycin (n = 25), prednisolone (n = 27), or placebo (n = 26).

• Bronchial wall thickness percentage did not change significantly in any of the groups. However, the inner radius and lumen area of azithromycin and prednisolone-treated subjects increased significantly.

• Azithromycin also significantly improved the dyspnea severity, ACT score, FENO, and FEV1, FEF25-75, and FEV1/FVC.

• Cough severity or asthma exacerbation rate did not change significantly after eight months of treatment with azithromycin.

Dr Sadeghdoust and team concluded that "Long-term treatment with azithromycin increased lumen radius and lumen area in patients with severe persistent asthma. However, there was no significant change in wall thickness in any of the treatment groups."

For further information: https://doi.org/10.1016/j.rmed.2021.106494