A new blood test developed by experts at Royal Brompton Hospital could give patients with idiopathic pulmonary fibrosis (IPF) a better idea of their prognosis and whether or not treatments that can slow down the progression of the disease are working.

The condition - thought to affect up to 20,000 people in the UK - causes progressive scarring of the lungs and is often fatal.

The Prospective Observation of Fibrosis in the Lung Clinical Endpoints (PROFILE) study, the largest and most detailed observational IPF study of its kind, recruited 214 patients, who were identified by Royal Brompton Hospital and the University of Nottingham. The findings have been published online in the Lancet Respiratory Medicine this week in a paper written by IPF experts, including Dr Toby Maher, consultant respiratory physician at Royal Brompton and head of the Fibrosis Research Group at Imperial College London, Anne-Marie Russell, senior research nurse at Royal Brompton and Dr Gisli Jenkins at the University of Nottingham.

The study, conducted at the National Institute for Health Research (NIHR) Royal Brompton Respiratory Biomedical Research Unit (BRU), took samples of blood and analysed the concentrations of several neoepitopes, which are types of proteins. These were measured at baseline and then at regular intervals throughout the following six months. Physiological measurements, including the amount of air which could be forcibly exhaled from the lungs and how much oxygen travels from air sacs (alveoli) in the lungs to the bloodstream, were also taken to detect how the condition was progressing.

The research, which is the largest and most detailed observational IPF study of its kind, showed that the concentration of neoepitopes were higher in people with the condition compared with healthy controls. Some of the biomarkers were associated with worsening disease and outcomes and changes in their concentrations after three months appeared to predict the progression of IPF earlier than the physiological measurements.

The results suggest that biomarkers could also be useful in the early stages of clinical trials for new treatments, as the measurements could indicate when the patient is responding to them.

Measurement of the neoepitopes may also be of use to clinicians when it comes to deciding what treatment to give patients, as it could potentially inform them if medication is working and thus help with the management of the disease.

This could now have particular use because there are two antifibrotic drugs, pirfenidone and nintedanib, which have been approved for use in the UK within the last two years and both have been shown to slow disease progression.

Commenting on the research, Dr Maher said:

"These biomarkers have the potential to improve the treatment of IPF by enabling doctors to determine whether treatments are working or not at an early stage and before permanent lung damage has developed. Furthermore, the biomarkers may enable clinical trials in IPF to be much shorter, something which should speed up the process of making new treatments available for this devastating disease."

Dr Maher and Dr Jenkins are involved in continued research which aims to make these blood tests available in specialist clinics. Further research, to search for other biomarkers of IPF and potential new ways of treating the disease, is ongoing.

It is not known why IPF occurs, but it appears to affect cells that line the alveoli in the lungs, causing them to become damaged and die. In response, the body tries to repair the damage by releasing fibroblast cells, but the over-production of these cells leads to scarring and hardening (fibrosis) of lung tissue. The scarring means the lungs cannot work properly and patients are often short of breath and have a persistent dry cough, fatigue and gastric reflux. Patients with the condition have an average life expectancy of three years and the number of cases in the UK is increasing by around five per cent a year.

Dr Maher said:

"Although newly available treatments may help, this ongoing research is required to ensure better outcomes for patients with IPF."

The research was funded by GlaxoSmithKline and the Medical Research Council and sponsored by Royal Brompton & Harefield NHS Foundation Trust and the University of Nottingham.

Royal Brompton has the only unit in the UK solely dedicated to the management of patients with interstitial lung disease (ILD), the term used for more than 200 lung diseases that affect the tissue and space around the air sacs in the lung, including IPF.

Experts at the hospital care for the largest number of IPF patients in the UK and receive around 1,000 new referrals every year.