TREPROSTINIL in Pulmonary Hypertension: Evidence and Clinical Trends

Multicenter Registry Evaluating Real-World Therapeutic Patterns and Outcomes in Newly Diagnosed Adult Patients With Pulmonary Arterial Hypertension (PAH) Treated With Parenteral Treprostinil

TRESPECT is an international, multicenter, observational registry designed to describe the real-world use, effectiveness, and tolerability of parenteral treprostinil in adults with newly diagnosed pulmonary arterial hypertension (PAH). The registry will include patients who initiated subcutaneous or intravenous treprostinil within 12 months of PAH diagnosis.

Both retrospective and prospective data will be collected from routine clinical care. Data will include patient characteristics, PAH treatment patterns, treprostinil dosing and route of administration, functional status, exercise capacity, biomarkers, echocardiographic and hemodynamic parameters, clinical events, and adverse events. Participants will be followed for at least 36 months or until a registry termination criterion is met. The registry is expected to enroll approximately 100 to 300 patients across specialized PAH centers in several European countries.

Study Overview

• Status: Not yet recruiting
• Conditions: Pulmonary Arterial Hypertension (PAH)
• Intervention / Treatment: Drug: treprostinil

• Study Type: Observational
• Enrollment (Estimated): 300

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

The registry will include approximately 100-300 adult patients (≥18 years of age) with confirmed pulmonary arterial hypertension (PAH), classified as Group 1 according to the prevailing ESC/ERS guidelines, who initiated parenteral treprostinil administered subcutaneously or intravenously on or after January 1, 2024. Written informed consent will be required for prospective data collection and for retrospective medical chart review, as applicable under local regulations.

Description

Inclusion Criteria:

• Adult patient (≥18 years)
• Confirmed diagnosis of PAH (i.e. Group 1 as defined by ESC/ERS guidelines)
• Initiated on parenteral Treprostinil (SC or IV) anytime from 1/1/2024
• Informed consent (prospective data or retrospective chart review, per local regulations)

Exclusion Criteria:

• Participation in any interventional trials affecting PAH (including patients from TripleTRE study)
• Non-PAH forms of pulmonary hypertension (e.g., ESC-ERS Group 2-5)

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Patients Treated With Parenteral Treprostinil; Adult patients with confirmed pulmonary arterial hypertension who initiated parenteral treprostinil administered by the subcutaneous or intravenous route within 12 months of PAH diagnosis. Treatment selection, route of administration, dosing, titration, concomitant PAH therapy, and clinical management are determined by the treating physician according to routine clinical practice. Clinical, treatment, safety, and outcome data are collected retrospectively and/or prospectively as part of this observational registry.

Drug: treprostinil; Parenteral treprostinil administered by continuous subcutaneous or intravenous infusion as part of routine clinical care. The decision to initiate treatment, route of administration, starting dose, dose titration, treatment duration, and use of concomitant PAH therapies are determined by the treating physician and are not assigned by the registry. Data on treatment initiation, doses at approximately 2 and 4 weeks, longitudinal dosing, route of administration, tolerability, local site reactions, pain, treatment changes, and clinical outcomes are collected during registry follow-up.; Other Names: Parenteral Treprostinil; Subcutaneous Treprostinil; Intravenous Treprostinil

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change From Baseline in 6-Minute Walk Distance at Month 12	Mean change in 6-minute walk distance from baseline to Month 12. The 6-minute walk distance is measured in meters. A positive change indicates improvement in exercise capacity.	Baseline and Month 12
Number and Percentage of Participants by Change in New York Heart Association Functional Class at Month 12	Number and percentage of participants whose New York Heart Association Functional Class improved, remained unchanged, or worsened from baseline to Month 12. Functional Class ranges from Class I to Class IV, with a higher class indicating greater functional limitation.	Baseline and Month 12
Number and Percentage of Participants With Local Administration-Site Reactions During the First 12 Months	Number and percentage of participants experiencing at least one local administration-site reaction associated with subcutaneous or intravenous treprostinil application during the first 12 months after treatment initiation.	From baseline through Month 12
Mean Local Pain Score During the First 12 Months	Local pain associated with parenteral treprostinil application will be assessed on a numerical rating scale from 0 to 10. Higher scores indicate greater pain.	Baseline, Week 2, Week 4, Month 3, Month 6, Month 9, and Month 12

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change From Baseline in N-Terminal Pro-B-Type Natriuretic Peptide at Month 12	Mean change in N-terminal pro-B-type natriuretic peptide concentration from baseline to Month 12.	Baseline and Month 12
Mean Change From Baseline in B-Type Natriuretic Peptide at Month 12	Mean change in B-type natriuretic peptide concentration from baseline to Month 12.	Baseline and Month 12
Overall survival	Overall survival is defined as the time from initiation of parenteral treprostinil to death from any cause.	From initiation of parenteral treprostinil until death from any cause, assessed up to 36 months
Number and Percentage of Participants by Reason for Early Initiation of Parenteral Treprostinil	Number and percentage of participants in each documented category of clinical reason for initiating parenteral treprostinil within 12 months of PAH diagnosis, irrespective of baseline risk category.	Baseline
Mean Parenteral Treprostinil Dose at each visit	Parenteral treprostinil dose will be summarized at each visit. Dose will be reported in the unit ng/kg/min.	Baseline, Week 2, Week 4, Month 3, Month 6, Month 9, Month 12, Month 18, Month 24, Month 30, and Month 36
Number and Percentage of Participants by Route of Parenteral Treprostinil Administration	Number and percentage of participants receiving parenteral treprostinil by subcutaneous or intravenous administration at each visit.	Baseline, Week 2, Week 4, Month 3, Month 6, Month 9, Month 12, Month 18, Month 24, Month 30, and Month 36
Number and Percentage of Participants Receiving Concomitant Pulmonary Arterial Hypertension Therapy	Number and percentage of participants receiving each recorded category of concomitant pulmonary arterial hypertension therapy.	Baseline, Month 3, Month 6, Month 9, Month 12, Month 18, Month 24, Month 30, and Month 36
Time to First Composite Clinical Worsening Event	Time from initiation of parenteral treprostinil to the first occurrence of death from any cause, PAH-related hospitalization, or lung transplantation.	From initiation of parenteral treprostinil until the first composite clinical worsening event, assessed up to 36 months
Number and Percentage of Participants With Adverse Events	Number and percentage of participants experiencing at least one adverse event during registry follow-up. Adverse events will be summarized by seriousness, severity, outcome, causal relationship to treprostinil, and action taken with treatment.	From baseline through Month 36

Collaborators and Investigators

• Sponsor: AOP Orphan Pharmaceuticals AG

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): December 1, 2029
• Study Completion (Estimated): December 1, 2031

Study Registration Dates

• First Submitted: July 20, 2026
• First Submitted That Met QC Criteria: July 26, 2026
• First Posted (Actual): July 30, 2026

Study Record Updates

• Last Update Posted (Actual): July 30, 2026
• Last Update Submitted That Met QC Criteria: July 26, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Pulmonary Arterial Hypertension; Observational Registry; Treprostinil; Subcutaneous Treprostinil; Parenteral Treprostinil
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Hypertension, Pulmonary; Pulmonary Arterial Hypertension; treprostinil
• Other Study ID Numbers: TRESPECT

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No