An observational study in Pulmonary Hypertension Due to Lung Diseases and Hypoxia, Pulmonary Hypertension and Interstitial Lung Disease, sponsored by United Therapeutics. Recruiting at 71 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-26.
Sponsored by United Therapeutics · Observational
This is a prospective, real world, multicenter, registry of patients with pulmonary hypertension associated with interstitial lung disease (PH-ILD) and interstitial lung disease (ILD).
The purpose of this study is to capture and analyze patient characteristics, treatment patterns, and clinical outcomes of patients with PH-ILD, with the goal of enhancing our current understanding of the disease state and its treatment outcomes. The study also aims to describe the disease trajectory of ILD patients at risk of pulmonary hypertension (PH).
In this registry, patients will be enrolled into 1 of 4 cohorts. Cohort 1 will include approximately 200 patients who are not receiving inhaled treprostinil at time of study enrollment. Cohort 2 will include approximately 300 patients who are newly initiated on Tyvaso/Tyvaso DPI. Cohort 3 will include approximately 300 patients who have been receiving Tyvaso/Tyvaso DPI for >90 days. Cohort 4 will include approximately 100 ILD patients with a prior right heart catheterization (RHC) not meeting the definition of PH.
As part of the registry, assessments will be completed for data collection in 6- or 12 month intervals, unless the data are already available via standard of care. This patient registry will follow patients for up to 5 years after enrollment.
Assessments include pulmonary function tests (PFTs) including diffusing capacity of the lungs for carbon monoxide (DLCO); high resolution computed tomography (HRCT); vital signs; 6-Minute Walk Test; blood draw for plasma N-terminal pro-BNP (NT-proBNP) concentration, genetics analysis, biomarker analysis; echocardiography; EuroQoL 5 Dimension 5 Level Questionnaire (EQ-5D-5L); King's Brief Interstitial Lung Disease Questionnaire (K-BILD); Living with Pulmonary Fibrosis Questionnaire (L-PF); Therapy Administration Questionnaire; emPHasis-10 Questionnaire; healthcare resource utilization; current medications and rehabilitation; WHO functional class; transplant status; palliative care data; survival data; and RHC.
1,076 studies on the registry are indexed under Hypoxia; 213 are open to participants now.
This study's planned enrollment of 900 is above the median of 79 across 277 observational studies indexed under Hypoxia.
Browse Hypoxia studies →United Therapeutics is the lead sponsor of 85 studies on the registry; 8 are open to participants now.
Of its 17 completed or terminated interventional studies of FDA-regulated products, 15 (88%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients with a diagnosis of pulmonary hypertension associated with interstitial lung disease or interstitial lung disease. This includes patients who are and aren't receiving inhaled treprostinil, excluding patients receiving Yutrepia™ at Baseline.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Diagnosis of fibrotic ILD based on high-resolution computed tomography imaging, including but not limited to:
For patients to be eligible for Cohorts 1 to 3: RHC confirmed PH (mean pulmonary artery pressure >20 mmHg, pulmonary artery wedge pressure
≤15 mmHg, pulmonary vascular resistance >2 WU).
Tyvaso/Tyvaso DPI at 1 of the following time points:
Exclusion Criteria:
Confirmed diagnosis of Group 1, 2, 4, or 5 PH
a. In cases in which a patient has a diagnosis of PH-ILD along with a concomitant diagnosis of another PH group (eg, Group 1), enrollment may be permitted at the Investigator's discretion if, in their clinical judgment, PH-ILD is the predominant driver of the patient's PH.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cohort 1 will include approximately 200 patients who are not receiving inhaled treprostinil at time of study enrollment.
Other: Prospective study assessments
Cohort 2 will include approximately 300 patients who are newly initiated on Tyvaso/Tyvaso DPI. For patients to be eligible for Cohort 2, they must have initiated Tyvaso/Tyvaso DPI at Baseline or ≤ 90 days prior to Baseline.
Other: Prospective study assessments
Cohort 3 will include approximately 300 patients who have been receiving Tyvaso/Tyvaso DPI for \> 90 days prior to Baseline.
Other: Prospective study assessments
Cohort 4 will include approximately 100 ILD patients with a prior RHC not meeting the definition of PH but has a pulmonary artery wedge pressure ≤ 15 mmHg.
Other: Prospective study assessments
Patients will complete prospective assessments at 6- and 12-month intervals for up to 5 years. There will be 1 check in at the first 3 months of enrollment. Follow up visits will include a ±45 day visit window. If an assessment is performed within 45 days of the visit window as part of the patient's standard of care, those values will be used in place of a prospective assessment.
Baseline characteristics as described by demographics, medical history, ILD history, PH history, family history (comorbidities), and diagnostic right heart catheterization values.
Time frame: Baseline
Changes in clinical features relating to patients' interstitial lung disease and pulmonary hypertension
Time frame: Followed prospectively for a maximum of 5 years from date of enrollment into the registry
Started Jan 2025 (actual). Primary completion is estimated for Sep 2030, 67 months after the start.
Of 30 industry-sponsored observational studies under Hypoxia, half reached primary completion within 0 months of starting (the median), counting those still running; a quarter within 0 and three quarters within 2.
Counting every sponsor, half of 155 studies reached it within 14 months; a quarter within 3 and three quarters within 46.
How these figures are worked out, and which studies are left out of them.
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