Real-world data collection on diagnosis, course and outcomes patients suffering PROgressive Fibrosing Interstitial Lung Disease

Interstitial lung diseases (ILDs) encompass a large and diverse group of restrictive lung diseases, which overlap in clinical presentations and patterns of lung injury (Cottin et al. 2019). Idiopathic pulmonary fibrosis (IPF) is the most common type of idiopathic ILD, and represents, by definition, the prototype of progressive fibrosing ILD (PF-ILD) (Raghu et al. 2011). It is characterized by a self-sustaining progressive fibrosis, worsening respiratory symptoms, declining lung function, worsening quality of life, and early death despite clinical management. Clinical data suggest that there is a larger group of patients with differing clinical ILD diagnoses (of known and unknown cause) who develop a progressive fibrosing phenotype during the course of their disease (Wuyts et al. 2020, Cottin et al. 2019, Maher et al. 2019). Because these conditions share similarities regarding pathogenesis and clinical behaviour, they are increasingly described under the umbrella terminology of ‘progressive fibrosing ILDs’ or ‘fibrosing ILD with a progressive phenotype (PF-ILD) (Wells et al. 2018). Many ILDs are formally classified as rare (Travis et al. 2013); and PF-ILD is a rare subgroup of ILD patients. Amongst the available literature, PF-ILD prevalence estimates range of 0.22 to 2.00 per 10.000 in Europe and 2.80 per 10.000 in the US. In Belgium PF-ILD prevalence is estimated to be 0.22 per 10.000 (Olson et al. 2018). According to the EMA and FDA definitions, PF-ILD can formally be considered as an orphan disease. In order to complement the data collected in clinical trials, we propose to gather data to describe the diagnosis, disease course and outcomes for PF-ILD patients in Belgium. The collected data will be used to answer uncertainties raised by the MEA (Managed Entry Agreement) working group following a MEA (Art. 111-113 Royal Decree of Feb 1st 2018).