A Study of Inhaled Treprostinil (LIQ861) in Adults With Pulmonary Arterial Hypertension Transitioning From Oral Selexipag

NCT07759804 | Not Yet Recruiting Phase 4 FDA Drug FDA Device

• 1 other identifier: LTI-403
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This study will look at safety and tolerability of LIQ861 (treprostinil) inhalation powder in adults with pulmonary arterial hypertension (PAH, WHO Group 1) who switch from selexipag, a medicine taken by mouth, to treprostinil, a medicine breathed into the lungs. Everyone who takes part will receive LIQ861. On the first study day, participants will stop taking selexipag and begin taking LIQ861 four times a day using a small handheld dry powder inhaler. The dose may be increased over time based on how well it is tolerated. Participants will take LIQ861 for 16 weeks. The study will also look at whether switching to LIQ861 affects walking distance, a blood marker of heart strain, and symptoms reported by participants.

Conditions

Pulmonary Arterial Hypertension (PAH)

Keywords

pulmonary arterial hypertension; PAH; selexipag; prostacyclin; dry powder inhaler

Outcome Measures

Primary Outcomes (1)

• Treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs)

  Day 1 through 30 days after the last dose of study drug (up to approximately 24 weeks)

Study Arms (1)

Selexipag to LIQ861 (treprostinil) inhalation powder

EXPERIMENTAL

Combination Product: LIQ861 (treprostinil) inhalation powder

Interventions

LIQ861 (treprostinil) inhalation powder COMBINATION_PRODUCT

Treprostinil inhalation powder supplied in capsules for oral inhalation using a handheld, single-capsule dry powder inhaler. Participants self-administer study drug four times daily (QID), and titrated on tolerability and symptom relief.

Selexipag to LIQ861 (treprostinil) inhalation powder

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male or female 18 to 80 years of age
• Documented findings on right heart catheterization consistent with a diagnosis of WHO Group 1 pulmonary arterial hypertension of one of the following subtypes: idiopathic PAH; heritable PAH; drug- or toxin-induced PAH; PAH associated with connective tissue disease; or PAH associated with simple congenital systemic-to-pulmonary shunts repaired at least 1 year previously
• Receiving selexipag at any dose between 200 and 1600 mcg twice daily for at least 90 days, and willing and able to transition from selexipag to LIQ861 due to unsatisfactory clinical response or tolerability issues
• May be receiving up to 2 additional approved non-prostacyclin oral PAH therapies at a stable dose and regimen, planned to continue unchanged for the duration of the study
• New York Heart Association Functional Class II or III
• Able to demonstrate correct use of the dry powder inhaler

You may not qualify if:

• Clinically significant left-sided heart disease by echocardiography, including left ventricular ejection fraction ≤ 45%, left atrial volume index \> 48 mL/m², or hemodynamically significant valvular disease
• Symptomatic coronary artery disease within the previous 6 months
• Prior atrial septostomy

Sponsors & Collaborators

• Liquidia Technologies, Inc.: lead

Study Sites (1)

Southeastern Cardiology Associates

Columbus, Georgia, 31904, United States

Location

MeSH Terms

Conditions

Pulmonary Arterial Hypertension

Interventions

treprostinil

Condition Hierarchy (Ancestors)

Hypertension, Pulmonary; Lung Diseases; Respiratory Tract Diseases

Central Study Contacts

Liquidia Point of Contact

CONTACT

1-888-241-6906; LiquidiaStudies@liquidia.com

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 7, 2026
• First Posted: August 12, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: August 12, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)