Summary

Interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) frequently results in ventilatory restriction, a major cause of death in these individuals. Clinical trials in patients with SSc-related ILD have traditionally used forced vital capacity percentage (FVC%) predicted as a primary outcome measure [Hoyles RK et al. Arthritis Rheum 2006; Tashkin DP et al. N Engl J Med 2006]. This article discusses the development of a composite outcome measure to assess treatment response in patients with SSc—ILD in clinical studies, and to create a more comprehensive measure than FVC% alone.