An observational study in Pulmonary Hypertension and Interstitial Lung Disease, sponsored by Liquidia Technologies, Inc.. Active, not recruiting at 18 sites in United States. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Liquidia Technologies, Inc. · Observational
Study LTI-401 is an open-label, multicenter study which will evaluate the safety and tolerability of LIQ861 in subjects who have WHO Group 1 \& 3 PH.
Open-label, multicenter study which will evaluate the safety and tolerability of LIQ861 in subjects who have WHO Group 1 \& 3 PH.
Cohort A will include approximately 60 subjects who have WHO Group 3 Pulmonary Hypertension associated with interstitial lung disease (PH-ILD)
Cohort B will include approximately 20 subjects who have WHO Group 3 PH-ILD, have been on protocol specified dosing of inhaled treprostinil QID, not at treatment goal, and able to transition to LIQ861.
The primary objective of this study is to evaluate the safety and tolerability of LIQ861 in subjects with WHO Group 1 \& 3 Pulmonary Hypertension (PH).
1,092 studies on the registry are indexed under Hypertension, Pulmonary; 244 are open to participants now.
This study's planned enrollment of 80 is below the median of 110 across 381 observational studies indexed under Hypertension, Pulmonary.
Browse Hypertension, Pulmonary studies →Liquidia Technologies, Inc. is the lead sponsor of 10 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Subject with PH-ILD
Cohort A Key Inclusion Criteria:
Has a confirmed diagnosis of WHO Group 3 PH-ILD based on CT chest imaging performed, which demonstrates evidence of diffuse parenchymal lung disease and /FVC (absolute values) ≥ 70% and are required to have evidence of pulmonary hypertension (PH) as demonstrated from right heart catheterization (RHC) with the following hemodynamic parameters.
i) Pulmonary vascular resistance (PVR) ≥ 3 Wood Units (WU) and ii) Pulmonary capillary wedge pressure (PCWP) of ≤ 15 mmHg and iii) A mean pulmonary arterial pressure (mPAP) of ≥ 30 mmHg.
OR
Cohort A Key Exclusion Criteria:
A Subject is not eligible for inclusion in the study if any of the following criteria apply:
Cohort B Key Inclusion Criteria
Has a diagnosis of WHO Group 3 PH-ILD confirmed with CT chest imaging performed at the screening visit, which demonstrates evidence of diffuse parenchymal lung disease and FEV1/FVC (absolute values) ≥70%. Subjects are required to have evidence of pulmonary hypertension (PH) as demonstrated from right heart catheterization (RHC) with the following documented parameters:
Cohort B Key Exclusion Criteria
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.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PH-ILD
Drug: LIQ861
PH-ILD
Drug: LIQ861
trepostinil inhalation powder in combination with inhaler
Cohort A: Incident of treatment-emergent drug/device-related adverse events and Serious Adverse Events (SAEs)
Treatment-emergent AEs and SAEs will be grouped by MedDRA System Organ Class, dose level at onset, time on drug at onset, and relationship to dose titration. Device-related AEs and SAEs will be grouped by MedDRA System Organ Class, dose level at onset, time on drug at onset, and relationship to dose titration.
Time frame: Baseline until the end of the study.
Cohort B: Number of participants with treatment-emergent drug/device-related adverse events and Serious Adverse Events (SAEs)
Treatment-emergent AEs and SAEs will be grouped by MedDRA System Organ Class, dose level at onset, time on drug at onset, and relationship to dose titration. Device-related AEs and SAEs will be grouped by MedDRA System Organ Class, dose level at onset, time on drug at onset, and relationship to dose titration.
Time frame: 16 weeks
Started Dec 2023 (actual). Primary completion is estimated for Jul 2027, 43 months after the start.
Of 168 observational studies under Hypertension, Pulmonary, half reached primary completion within 59 months of starting (the median), counting those still running; a quarter within 24 and three quarters within 107. This study's planned 43 months is below that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Liquidia Technologies, Inc.