Iguratimod attenuates general disease activity and improves lung function in rheumatoid arthritis-associated interstitial lung disease patients.

OBJECTIVE: Iguratimod is a new kind of synthetic small molecule disease modified anti-rheumatic drug with good efficacy for rheumatoid arthritis (RA) treatment; meanwhile, it exhibits potency to alleviate alveolar inflammation and pulmonary fibrosis. However, its application in RA interstitial lung disease (ILD) patients is seldomly reported. Thus, the current study aimed to investigate the efficacy and safety of iguratimod plus glucocorticoid/cyclophosphamide vs. glucocorticoid/cyclophosphamide in treating RA-ILD patients. PATIENTS AND METHODS: Totally 101 RA-ILD patients underwent glucocorticoid/cyclophosphamide (Control group: n=61) or iguratimod plus glucocorticoid/cyclophosphamide (Iguratimod group: n=40) treatment were analyzed. General inflammation, disease activity, serum disease marker levels, high resolution lung computed tomography (HRCT) score, lung function indexes were evaluated within 24-week (W) treatment. RESULTS: No difference of baseline demographic or disease-related features was observed between Iguratimod group and Control group. Iguratimod group showed lower levels of CRP and ESR at W4, W12 and W24; as well as decreased DAS28 score, rheumatoid factor and anti-cyclic citrullinate peptide antibody levels at W12 and W24 compared to Control group. HRCT score showed no difference between Iguratimod group and Control group at any time points. As to lung function indexes, forced vital capacity percent predicted [FVC (% predicted)], carbon monoxide diffusion capacity percent predicted [DLCO (%predicted)] and 6-minute-walk distance (6MWD) were all higher in Iguratimod group compared with Control group at W4, W12 and W24. Besides, no difference in adverse events was discovered between these two groups. CONCLUSIONS: Iguratimod attenuates general inflammation, disease activity, and improves lung function in RA-ILD patients.