A total of 120 Chinese patients with connective tissue disease-associated interstitial lung disease (CTD-ILD), including inflammatory myopathy (IIM), rheumatoid arthritis (RA), systemic sclerosis (SSc), and other connective tissue diseases, will be enrolled to use Pirfenidone or not in this study according to 2:1 random entry. Glucocorticoid and immunosuppressants worked as background treatment.~The main research endpoint is the lung function (FVC) at 6 months. The clinical dyspnea score, 6-minute walking distance, lung function and imaging indicators, primary disease activity index are evaluated regularly until 24 months. The relationship of pirfenidone concentration, clinical effect and safety, immune function will be analyzed also.
A single-center randomized controlled study will be used to observe the efficacy and safety of pirfenidone on CTD-ILD patients for 24 months.~The main research endpoints is the lung function (FVC) at 6 months. The clinical dyspnea score, 6-minute walking distance, index of lung function and imaging indicators are evaluated, as well as primary disease activity and adverse reactions of therapy with glucocorticoid and immunosuppressants up to 24 months.