Efficacy and safety of antifibrotic agents in the treatment of CTD-ILD and RA-ILD: A systematic review and meta-analysis

ObjectiveThe clinical spectrum of connective tissue disease-associated interstitial lung disease (CTD-ILD) and rheumatoid arthritis-associated interstitial lung disease (RA-ILD) ranges from asymptomatic findings on radiographic imaging to a rapidly progressive illness leading to respiratory failure and death. The treatment is always challenging due to the paucity of proven effective treatments. Nintedanib and pirfenidone are recently approved antifibrotics in idiopathic pulmonary fibrosis. This study aimed to investigate the efficacy and safety of antifibrotic agents in the treatment of CTD-ILD and RA-ILD.MethodsRelevant databases were searched for randomized controlled trials that compared pirfenidone or nintedanib with placebo in patients with CTD-ILD and RA-ILD. The primary outcome was the change in forced vital capacity (FVC). The odds ratio or risk ratio with 95% confidence interval (CI) was estimated for categorical data, and the mean difference with 95% CI was estimated for continuous data. The I2 statistic was used to assess heterogeneity, and meta-analysis was performed when possible.ResultsTen studies with a total of 880 participants met the inclusion criteria. Of these, four studies were included in the meta-analysis. According to the pooled result, the annual decline of FVC was significantly decreased in the antifibrotic agent arm compared to that in the placebo arm (MD 70.58 mL/yr, 95% CI 40.55 to 100.61).ConclusionThis review suggests a potential benefit and safety of antifibrotic treatment in slowing the decline of FVC in patients with CTD-ILD and RA-ILD. Further large-sample, random-controlled, high-quality trials are needed to provide more evidence in the decision-making regarding the use of antifibrotics in this group of patients.Clinical trial registrationPROSPERO; No: CRD42022369112; URL: https://www.crd.york.ac.uk/prospero/.