Is macitentan not a treatment option for digital ulcers in systemic sclerosis?
Systemic sclerosis (SSc) is a chronic autoimmune and vascular disease resulting in extensive tissue fibrosis of the skin and various internal organs with unknown etiology. Although the entire pathogenesis of SSc still remains elusive, the canonical wisdom is that a complex network of cytokines, growth factors, chemokines, and cell adhesion molecules drives the three pathological components of this disease, including autoimmunity/inflammation, vasculopathy, and fibrosis, which co-operatively promote disease progression. The emergence of molecular targeting therapy has disclosed a hierarchical structure of complex molecular network in various diseases, including SSc (1-3). As a part of recent advances in the treatment of SSc, a dual endothelin receptor antagonist, bosentan, has provided strict evidence indicating a vital role of endothelins in the pathogenesis of SSc, especially its vascular aspect (4,5).