Progressive fibrosing ILD phenotype

18% to 32% of patients with non-IPF ILDs may develop a progressive fibrosing phenotype1

ILD patients with the HRCT scans in their hands.


In ILDs, the progressive fibrosing phenotype is defined by the presence of:2–5

Icon of lungs affected by the extent of fibrosis.

Increase in extent of fibrosis on HRCT

Icon of person coughing representing worsening respiratory symptoms.

Worsening respiratory symtoms

Icon of lungs with their declined function.

Declining lung function

In progressive fibrosing ILD, pulmonary fibrosis continues to develop independent of the originating disease or trigger, along common pathogenic pathways3,4,6,7

IPF is considered as the most typical progressive fibrosing ILD2

Female patient with fibrotic cHP

All patients with IPF by definition have progressive disease2

IPF is inherently progressive making it relentless and deadly in all patients8–11


The progressive nature of IPF from diagnosis9

Rapid disease progression of IPF following acute exacerbation of IPF

Schematic representation of the natural history of IPF9
Reprinted from Annals of the American Thoracic Society, 183(6), Raghu et al, An Official ATS/ERS/JRS/ALAT Statement: Idiopathic Pulmonary Fibrosis: Evidence-based Guidelines for Diagnosis and Management, p788–824, ©2022


Types of ILDs that may be associated with a progressive fibrosing phenotype2,5

Range of ILDs at risk of developing the progressive fibrosing phenotype

Current Medical Research and Opinion, 2019, reprinted by permission of the publisher Informa UK Limited trading as Taylor & Francis Ltd.


Estimated percentage of patients diagnosed with ILD* that may develop a progressive fibrosing phenotype12

Estimated prevalence of the progressive fibrosing phenotype in a range of ILDs

Based on an online physician survey.†‡§¶

The combined prevalence of ILDs (other than IPF) with a progressive fibrosing phenotype are likely to equal or exceed those of IPF13,14


In patients with progressive fibrosing ILDs, cough, dyspnea and fatigue limit physical functional capacity, as well as the ability to perform basic activities and participate in everyday life3,15–17

Icon of person coughing representing worsening respiratory symptoms.


Dyspnea / breathlessness icon.


Worried person, sitting on the chair icon.


In addition to the functional impact, patients with progressive fibrosing ILD may suffer emotional distress, including feelings of depression, loss of independence, and powerlessness.3,15,17–19

Worried person, sitting on the chair icon.


Icon of person under the raining cloud, symbolizing powerlessness


Icon of two people shaking hands, demonstrating co-dependency.

Loss of independence

Icon of person with thunderstorms above the head, symbolizing anxiety.


Patients with progressive fibrosing ILDs, such as IPF, HP and CTD-ILD, report almost universal symptoms of anxiety and/or depression.17,19


Progressive fibrosing ILD is characterized by progression of pulmonary fibrosis, worsening of symptoms, decline in lung function and deterioration in health-related quality of life5

Characteristics and potential impacts of the progressive fibrosing phenotype


Overview of the characteristics and prevalence of the progressive fibrosing phenotype across a wide range of ILDs

Patients with interstitial lung diseases face an unpredictable journey.There are over 200 types of ILDs, of which Idiopathic pulmonary fibrosis, or IPF, is the most common fibrosing type. Around 1 in 5 patients with differing ILD diagnoses may develop a ‘progressive fibrosing phenotype’.Progressive fibrosing ILDs are believed to progress via common pathobiological fibrotic pathways, independent of the original trigger.These progressive fibrosing ILDs are characterised by self-sustaining, diffuse and irreversible fibrosis, worsening respiratory symptoms and declining lung function.  The progressive and permanent fibrotic lung damage can place an overwhelming burden on patient’s quality of life and is associated with high mortality.  No treatments are currently approved for progressive fibrosing ILDs, other than IPF. Thus, there is a high unmet need for effective treatments that slow the disease progression in these patients. Boehringer Ingelheim has a strong commitment to scientific research. The INBUILD® clinical trial is the first and largest phase III global trial to include patients across the broad spectrum of ILDs that develop the ‘progressive fibrosing phenotype’, into a single trial.So together, we hope to help patients with progressive fibrosing ILDs find new ways forward. 

Dr. Nazia Chaudhuri outlines the physical and emotional impacts of the progressive fibrosing phenotype on patients and how it can develop in ILDs regardless of their underlying trigger


My name’s Nazia Chaudhuri, I’m a chest physician and the clinical lead of the Interstitial Lung Disease unit at the Manchester University NHS Foundation trust. I’m also the Chief Investigator of the progressive fibrosing interstitial lung disease clinical trial.What I thought I’d do today first, before I talk to you about the trial is just remind everybody what fibrosis means to a patients and what impact it has on our patients. One of the difficult things I find as a doctor when I have a patient in front of me with fibrosing lung disease, is to actually explain to them that it is an incurable disease and it often is progressive.Our patients will develop progressive breathlessness and cough, as well as anxiety and depression and at the moment, there’s very little evidence-based treatments for progressive interstitial lung disease bar idiopathic pulmonary fibrosis.There are a number of fibrotic lung diseases that look like and behave like IPF. Like IPF, they have a progressive decline and there’s no established treatments to try and halt that decline. Even though the initial trigger may be different, it’s likely that the pathogenetic mechanisms and the end stage fibrosis is the same. These include patients with connective tissue diseases like rheumatoid arthritis that have similar decline and prognosis as idiopathic pulmonary fibrosis. Other conditions include chronic hypersensitivity pneumonitis, sarcoidosis and asbestosis. These conditions can all have progressive declines in their lung function and can have a major impact on patients with symptoms of breathlessness, cough and can ultimately reduce survival. 

Slowing ILD progression is of critical importance in patients with a progressive fibrosing ILD as the risk of early death is heightened3

The first step to slowing progressive fibrosing ILD is identification

  • *
    Data based on online surveys with 486 physicians.12
  • Patients diagnosed with ILD other than IPF.
  • Progressive fibrosis was defined as fibrosis detected by HRCT (i.e. reticular abnormality with traction bronchiectasis with or without honeycombing) that was progressive in terms of worsening of lung function (FVC and/or DLCO) and/or respiratory symptoms and/or chest images.
  • §
    Research funded by Boehringer Ingelheim.
  • Estimates of the percentage of patients with non-IPF ILD that develop progressive fibrosis based on an online survey of 486 physicians (243 pulmonologists, 203 rheumatologists and 40 internists) from the United States, Japan, France, Germany, Italy, Spain and the United Kingdom.
  • CTD-ILD, connective tissue disease-associated; DLCO, diffusing capacity of the lung for carbon; FVC, forced vital capacity; HP, hypersensitivity pneumonitis; HRCT, high-resolution computed tomography; HRQoL, health-related quality of life; IIP, idiopathic interstitial pneumonia; ILD, interstitial lung disease; iNSIP, idiopathic non-specific interstitial pneumonia; IPF, idiopathic pulmonary fibrosis; PFT, pulmonary function test; RA-ILD, rheumatoid arthritis-associated interstitial lung disease; SSc-ILD, systemic sclerosis-associated interstitial lung disease.

  1. Wijsenbeek M, Kreuter M, Fischer A, et al. Non-IPF progressive fibrosing interstitial lung disease (PF-ILD): the patient journey. Am J Respir Crit Care Med. 2018;197:1-2.

  2. Cottin V, Wollin L, Fischer A, et al. Fibrosing interstitial lung diseases: knowns and unknowns. Eur Respir Rev. 2019b;28(151):pii:180100. 

  3. Flaherty KR, Brown KK, Wells AU, et al. Design of the PF-ILD trial: A double-blind, randomised, placebo-controlled phase III trial of nintedanib in patients with progressive fibrosing interstitial lung disease. BMJ Open Resp Res. 2017;4(1):e000212.
  4. Cottin V, Hirani N, Hotchkin D, et al. Presentation, diagnosis and clinical course of the spectrum of progressive-fibrosing interstitial lung diseases. Eur Respir Rev. 2018;27(150):180076. Cottin V, Hirani N, Hotchkin D, et al. Presentation, diagnosis and clinical course of the spectrum of progressive-fibrosing interstitial lung diseases. Eur Respir Rev. 2018;27(150):180076. 
  5. Kolb M, Vašáková M. The natural history of progressive fibrosing interstitial lung diseases. Respir Res. 2019;20(1).
  6. Selman M, King TE, Pardo A; American Thoracic Society; European Respiratory Society; American College of Chest Physicians. Idiopathic pulmonary fibrosis: prevailing and evolving hypotheses about its pathogenesis and implications for therapy. Ann Intern Med. 2001;134(2):136–151.
  7. Bagnato G, Harari S. Cellular interactions in the pathogenesis of interstitial lung diseases. Eur Respir Rev. 2015;24(135):102–114.
  8. van Manen MJ, Geelhoed JJ, Tak NC, Wijsenbeek MS. Optimizing quality of life in patients with idiopathic pulmonary fibrosis. Ther Adv Respir Dis. 2017;11(3):157–169.
  9. Raghu G, Collard HR, Egan JJ, et al; on behalf of the ATS/ERS/JRS/ALAT Committee on Idiopathic Pulmonary Fibrosis. An official ATS/ERS/JRS/ALAT statement: idiopathic pulmonary fibrosis: evidence-based guidelines for diagnosis and management. Am J Respir Crit Care Med. 2011;183(6):788–824.
  10. Molina-Molina M, Aburto M, Acosta O, et al. Importance of early diagnosis and treatment in idiopathic pulmonary fibrosis. Exp Rev Resp Med. 2018;12(7):537–539.
  11. Vancheri C, Failla M, Crimi N, Raghu G. Idiopathic pulmonary fibrosis: a disease with similarities and links to cancer biology. Eur Respir J. 2010;35(3):496–504. 
  12. Wijsenbeek MS, Kreuter M, Olson A, et al. Progressive fibrosing interstitial lung diseases: current practice in diagnosis and management. Curr Med Res Opin. 2019:1–10. 
  13. Holtze C, Flaherty K, Kreuter M, et al. Healthcare utilisation and costs in the diagnosis and treatment of progressive-fibrosing interstitial lung diseases. Eur Respir Rev. 2018;27(150):180078.
  14. Olson AL, Gifford AH, Inase N, et al. The epidemiology of idiopathic pulmonary fibrosis and interstitial lung diseases at risk of a progressive-fibrosing phenotype. Eur Respir Rev. 2018;27(150):pii:180077.
  15. Swigris JJ, Brown KK, Abdulqawi R, et al. Patients’ perceptions and patient-reported outcomes in progressive-fibrosing interstitial lung diseases. Eur Respir Rev. 2018;27(150):pii:180075. 
  16. Olson AL, Brown KK, Swigris JJ. Understanding and optimizing health-related quality of life and physical functional capacity in idiopathic pulmonary fibrosis. Patient Relat Outcome Meas. 2016;7:29-35.
  17. Morisset J, Dubé B, Garvey C, et al. The Unmet Educational Needs of Patients with Interstitial Lung Disease: Setting the Stage for Tailored Pulmonary Rehabilitation. Ann Am Thorac Soc. 2016;13:1026–1033.
  18. Duck A, Spencer LG, Bailey S, et al. Perceptions, experiences and needs of patients with idiopathic pulmonary fibrosis. J Adv Nurs. 2014;71(5):1055-1065.
  19. Hinz A, Brähler E, Möde R, et al. Anxiety and depression in sarcoidosis: the influence of age, gender, affected organs, concomitant diseases and dyspnoea. Sarcoidosis Vasc Diffuse Lung Dis. 2012;29(2):139-146.
  20. Wuyts WA, Agostini C, Antoniou KM, et al. The pathogenesis of pulmonary fibrosis: a moving target. Eur Respir J. 2013;41(5):1207–1218.

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