Systemic Sclerosis–Associated Interstitial Lung Disease: How to Incorporate Two Food and Drug Administration–Approved Therapies in Clinical Practice
Dinesh Khanna, Alain Lescoat, David Roofeh, Elana J. Bernstein, Ella A. Kazerooni, Michael D. Roth, Fernando J. Martínez, Kevin R. Flaherty, Christopher P. Denton
Abstract
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 US Food and Drug Administration (FDA) and indicated for slowing the rate of decline in pulmonary function in patients with SSc-associated ILD (SSc-ILD): nintedanib (a tyrosine kinase inhibitor) and tocilizumab (the first biologic agent targeting the interleukin-6 pathway in SSc). In addition, 2 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 for the management of SSc-ILD is still to be determined. The objectives of this review are 2-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 versus clinical ILD) and associated risk of progression (low versus high risk). The pharmacologic and nonpharmacologic options for first- and second-line therapy, as well as potential combination approaches, are discussed in light of the recent approval of tocilizumab for SSc-ILD.