Efficacy of azithromycin for treatment of acute exacerbation of chronic fibrosing interstitial pneumonia: a prospective, open-label study with historical controls.

BACKGROUND

Acute exacerbation of chronic fibrosing interstitial pneumonia (AE-CFIP) is an often fatal condition with no established treatment. Recently, macrolides were found to be beneficial in cases of acute lung injury.

OBJECTIVES

To examine the clinical effectiveness and safety of intravenous azithromycin in patients hospitalized for AE-CFIP.

METHODS

A prospective, open-label study with historical controls was conducted. Twenty consecutive patients with AE-CFIP received azithromycin. They were compared with a historical cohort treated with fluoroquinolone (n = 56). All patients received high-dose steroid pulse therapy. The primary end point was mortality at 60 days. The secondary end point was safety of intravenous azithromycin in patients with AE-CFIP. Inverse probability of treatment weighting (IPTW) using the propensity score was performed to investigate the relationship between azithromycin use and survival time.

RESULTS

Mortality was significantly lower in the patients treated with azithromycin than in those treated with fluoroquinolone (mortality rate at 60 days: 20 vs. 69.6%, p < 0.001; median survival time: not reached vs. 29.5 days, p < 0.001). The IPTW adjusted hazard of mortality at 60 days in patients receiving azithromycin was 0.17 (95% CI 0.05-0.61). No serious adverse events were observed.

CONCLUSIONS

Azithromycin was associated with improved outcomes in patients with AE-CFIP. Further studies are needed to verify this finding (Clinical trial JMA-IIA00095).