SYSTEMIC SCLEROSIS-ASSOCIATED INTERSTITIAL LUNG DISEASE: How to incorporate two Food and Drug Administration-approved therapies in clinical practice.

Systemic sclerosis (SSc; scleroderma) has the highest individual mortality of all rheumatic diseases and interstitial lung disease (ILD) is among the leading causes of SSc-related death. Two drugs are now approved by the Food and Drug Administration (FDA) and indicated for slowing the rate of decline in pulmonary function in patients with SSc-ILD: nintedanib (a tyrosine kinase inhibitor) and tocilizumab (the first biologic agent targeting the interleukin-6 pathway in SSc). In addition, two generic drugs with cytotoxic and immunoregulatory activity, mycophenolate mofetil and cyclophosphamide, have shown comparable efficacy in a Phase II trial but are not FDA-approved for SSc-ILD. In light of the heterogeneity of the disease, the optimal therapeutic strategy in the management of patients with SSc-ILD is still to be determined. The objectives of this review are two-fold: (1) review the body of research focused on the diagnosis and treatment of SSc-ILD; and (2) propose a practical approach for diagnosis, stratification, management, and therapeutic decision-making in this clinical context. This review presents a practical classification of SSc patients in terms of disease severity (subclinical vs. clinical ILD) and associated risk of progression (low vs. high risk). The pharmacological and non-pharmacological options as first and second-line therapy, as well as potential combination approaches, are discussed in light of the recent approval of tocilizumab for SSc-ILD.