Context: Despite the investigation of multiple therapeutic options, idiopathic pulmonary fibrosis (IPF) remains a devastating, progressively fatal disease. Much interest has focused on the use of interferon (IFN)-gamma1b therapy, but the efficacy of this treatment has not been proven.
Objective: To determine whether IFN treatment reduces mortality in patients with IPF.
Design: A meta-analysis of randomized controlled trials evaluating the use of IFN-gamma1b as treatment for IPF.
Main outcome measure: Mortality in patients treated with IFN-gamma1b was compared to mortality in patients treated with control therapies.
Results: A total of three studies involving 390 patients was included in the analysis. IFN-gamma1b therapy was associated with reduced mortality (hazard ratio [HR], 0.418; 95% confidence interval [CI], 0.253 to 0.690; p = 0.0003). A comparison of mortality at different time points revealed that IFN-gamma1b therapy was associated with significantly reduced mortality at 1 year (0.0861; 95% CI, 0.0244 to 0.1478; p = 0.0063), 18 months (0.1682; 95% CI, 0.1065 to 0.2299; p < 0.0001), 650 days (0.1939; 95% CI, 0.1386 to 0.2492; p < 0.0001), and 2 years (0.2652; 95% CI, 0.1652 to 0.3652; p < 0.0001).
Conclusion: When the results of multiple studies are combined in a meta-analysis, IFN-gamma1b therapy is associated with reduced mortality.