Current and Emerging Treatment Options in Interstitial Lung Disease

Abstract

Interstitial lung disease (ILD) arises both de novo and in the context of a range of well-defined disorders most notably the connective tissue diseases. The ILDs are characterised by inflammation and/or fibrosis of the interstitial space and give rise to gas exchange abnormalities resulting in dyspnoea. Historically, treatment of ILD has revolved around the use of immunosuppression. More recently, the observation that combined prednisolone and azathioprine is deleterious in idiopathic pulmonary fibrosis and the licencing, in some territories, of the novel anti-fibrotic drug pirfenidone have resulted in an evolution in therapy for this group of disorders. For ILDs where the primary lesion is inflammatory or immune mediated, e.g. the connective tissue disease ILDs, amelioration of inflammation through the use of immunosuppressive therapy remains the primary treatment goal. Although trial evidence is limited, there is growing evidence to support the use of cyclophosphamide and rituximab in extensive or progressive inflammatory-driven ILD. In IPF by contrast, where inflammation is a minor component of disease, pirfenidone represents an important treatment advance. Ongoing clinical trials promise the development of a range of anti-fibrotic drugs in the near future. Observations derived from IPF are likely, once the evidence base permits, to result in significant changes in the management of fibrotic ILD irrespective of underlying cause. This chapter covers current understanding of the role of existing immunosuppressants and anti-fibrotic compounds across the spectrum of ILDs.