No effect of danazol treatment in patients with advanced idiopathic pulmonary fibrosis

BACKGROUND: Telomere dysfunction can underly the development of idiopathic pulmonary fibrosis (IPF), and recent work suggests that patients with telomere syndromes might benefit from treatment with androgens, such as danazol. METHODS: This was a prospective observational cohort study. 50 patients with IPF received off-label treatment with danazol after they showed progressive disease under treatment with pirfenidone or nintedanib. The primary outcome was the difference in yearly decline in forced vital capacity (FVC) prior to (pre) and after (post) start of treatment with danazol. RESULTS: There was no significant difference in FVC-decline between 1 year pre and 1 year post start of danazol treatment (mean decline pre 395 mL (95% confidence interval (CI) 290–500) compared to post 461 mL (95% CI 259–712); p=0.46; paired t-test). 11 patients (22%) were still on danazol after 1 year, and 39 patients had stopped danazol, mainly because of side-effects (56%) or death (33%). In patients who were still using danazol after 1 year, FVC-decline significantly slowed down under danazol treatment (mean pre 512 mL (95% CI 308–716) versus post 198 mL (95% CI 16–380); p=0.04). Median survival post danazol was 14.9 months (95% CI 11.0–18.8). CONCLUSION: Danazol as a treatment of last resort in patients with IPF did not lead to slowing of lung function decline and was associated with significant side-effects. It remains to be determined if earlier treatment or treatment of specific patient subgroups is beneficial.