The role of antifibrotic therapies in the treatment of systemic sclerosis-associated interstitial lung disease.

Systemic sclerosis (SSc) is a rare autoimmune condition with complex pathogenesis characterized by a heterogeneous presentation and different disease courses. Fibrosis of multiple organs including the lungs favored by inflammation and vasculopathy is the hallmark of SSc. SSc-associated interstitial lung disease (SSc-ILD) is common and can be associated with poor outcomes, this complication being the leading cause of death in recent series. Because of its huge heterogeneity, SSc-ILD management can be very challenging. Immunosuppressive therapy has long been used to prevent SSc-ILD progression with modest effects in clinical trials. However, thanks to a better understating of SSc pathogenesis, innovative therapies including antifibrotics are increasingly being developed. The achievement of the Safety and Efficacy of Nintedanib in Systemic SClerosIS (SENSCIS) trial has led to the approval by drug agencies of the first antifibrotic drug for SSc-ILD. In parallel, other antifibrotics are being investigated as possible beneficial therapies in SSc-ILD. An important unmet need remains to clarify the positioning of the various strategies, such as the added value of combination of immunosuppressants and antifibrotic therapies in patients at high risk of progression. Indeed, irreversible lung injury or self-perpetuated progression highlights the concept of a window of opportunity in SSc-ILD patients. Herewith, we provide an overview of the most significant clinical trials with antifibrotic drugs developed in recent years for the management of SSc-ILD and a viewpoint about their positioning in treatment algorithms.