Azithromycin for the Treatment of Obliterative Bronchiolitis after Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis

- There is a paucity of studies on therapies for the treatment of OB/BOS.
- Pooled change in FEV1 with azithromycin was not statistically significant.
- Current evidence cannot support or refute the use of azithromycin in this setting.
- Further studies are needed to evaluate therapies for OB/BOS after HSCT.

Obliterative bronchiolitis (OB) is a major cause of morbidity and mortality in patients undergoing hematopoietic stem cell transplantation (HSCT). Our objective was to perform a systematic review and meta-analysis of the impact of azithromycin on change in forced expiratory volume in 1 second (FEV1). We searched MEDLINE, EMBASE, Web of Science, Cochrane CENTRAL and Scopus databases and included studies that compared azithromycin with placebo or no intervention in the treatment of OB or bronchiolitis obliterans syndrome (BOS) in patients who had undergone allogeneic HSCT. Ninety-one unique publications were identified, and 4 studies met inclusion criteria, with a total of 90 patients. Changes in FEV1 were measured between 12 and 24 weeks after initiation of treatment. The meta-analysis demonstrated a mean increase in FEV1 of 30 mL (95% confidence interval, −260 to +330 mL; P = .82) after initiation of azithromycin. One patient death was reported but not attributed to azithromycin therapy. In conclusion, current evidence can neither support nor refute the use of azithromycin in the treatment of patients who develop OB/BOS after HSCT. Further studies are needed to determine whether azithromycin is beneficial for the treatment of OB/BOS in this setting.