Learnings from clinical trials in patients with connective tissue disease-associated interstitial lung disease

Many clinical trial results are available to inform best practices in the treatment of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD). Herein, we summarize the results of clinical trials, including patient-reported outcome instruments, for the treatment of patients with ILD associated with systemic sclerosis (SSc/scleroderma), rheumatoid arthritis, and idiopathic inflammatory myositis, the diseases with the most available data. For SSc-ILD, the US Food and Drug Administration approved nintedanib (a tyrosine kinase inhibitor) in 2020 and subcutaneous tocilizumab (an IL-6 receptor monoclonal antibody) in 2021. Rituximab was recently shown to have similar efficacy but better tolerability than intravenous cyclophosphamide (CYC) for CTD-ILD therapy. Scleroderma Lung Study II, conducted in patients with SSc-ILD, showed that oral CYC and mycophenolate mofetil (MMF) were comparable in their effects on lung function, but MMF was better tolerated. The increasing treatment armamentarium for patients with CTD-ILD offers physicians new opportunities to improve patient outcomes.