Unmet need in pulmonary hypertension-associated interstitial lung disease (PH-ILD): a clinician survey of real-world management of PH-ILD in Europe.

Background: With no approved therapies for pulmonary hypertension (PH) associated with interstitial lung disease (PH-ILD) in Europe, we surveyed clinician perceptions on PH-ILD management and unmet need to understand current real-world practices. Methods: An online clinician survey on PH-ILD management was conducted in France, Germany, Italy, Spain and the UK. Results: 55 clinicians (78% pulmonologists), each managing a median 20 PH-ILD patients (interquartile range (IQR) 10-50), participated. Upon PH suspicion, clinicians referred a median 50% (IQR 20-73%) of patients for echocardiography alone and 35% (IQR 20-78%) for echocardiography, followed by right heart catheterisation. Upon diagnosis, a median 20% (IQR 9-30%), 40% (IQR 20-50%) and 35% (IQR 20-55%) of patients fell under the pulmonary arterial pressure ranges of 21-24 mmHg, 25-34 mmHg and >35 mmHg, respectively. 50% of patients received off-label treatment for their PH and, of those, off-label phosphodiesterase-5 inhibitor (PDE-5i), endothelin receptor antagonist (ERA) and prostacyclin analogues were prescribed first-line by 78%, 9% and 7% of clinicians, respectively. Upon PDE-5i non-response, 35% of clinicians proceed with an ERA, 35% with no further therapy. 55% of clinicians used dual-therapy. Yearly median inpatient admissions and emergency visits were 2.0 (IQR 1.3-2.9) and 1.5 (IQR 1.0-2.0), respectively (n=31 responses). Most clinicians (69%) highlighted lack of efficacy or evidence for current therapies as a key gap in PH-ILD management. Conclusions: This study gives insight into real-world European PH-ILD diagnosis and management. With significant use of off-label treatment, there is a large unmet need due to lack of approved therapies. Despite updated guidelines, more evidence is needed to standardise PH-ILD management.