Pulmonary Artery Remodelling With Bosentan

June 1, 2026 updated by: Actelion

Open Label, Non Comparative Study to Investigate the Effect of Bosentan on Pulmonary Artery Remodelling in Pulmonary Arterial Hypertension (PAH).

The main purpose of this study is to investigate whether bosentan (Tracleer®) affects the wall thickness of the pulmonary arteries in patients with idiopathic pulmonary arterial hypertension (iPAH) and PAH related to systemic sclerosis (PAH-SSc).

The second purpose is to investigate if bosentan affects the enlargement of small vessels in the lungs in response to natural chemicals in patients with iPAH and PAH-SSc.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

11

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Australia
      • Camperdown, Australia
        • Royal Prince Alfred Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria : · Men or women >18 years of age.·

  • Symptomatic (modified NYHA class III) iPAH or PAH-SSc·
  • PAH confirmed by right heart catheterization performed within 3 months before enrolment mPAP > 25 mmHg, PCWP < 15 mmHg and PVR > 3 mmHg/l/min.
  • Women of childbearing potential must have a negative pre-treatment pregnancy test and use a reliable method of contraception during study treatment and for 3 months after study treatment termination.
  • Bosentan naïve patients

Exclusion Criteria : · PAH other than iPAH or PAH-SSc

  • Significant vasoreactivity during right heart catheterization defined as a fall in mPAP to < 40 mmHg with a decrease >= 10 mmHg and with a normal cardiac index (>= 2.5 l/min.m2)· Severe obstructive lung disease: FEV1/FVC < 0.5
  • Severe restrictive lung disease: TLC < 0.7 of normal predicted value
  • Hemoglobin <75% of the lower limit of the normal range· Systolic blood pressure < 85 mmHg
  • Body weight < 40 kg
  • Pregnancy or breast-feeding
  • Moderate to severe hepatic impairment, i.e., Child-Pugh Class B or C.
  • Baseline aminotransferases, i.e., aspartate aminotransferases (AST) and/or alanine aminotransferases (ALT) > 3 times the upper limit of the normal (ULN) range.
  • Treatment for iPAH or PAH-SSc within 1 month before start of study treatment, excluding warfarin and acute administration of vasodilators for vascular reactivity testing during heart catheterization.
  • Treatment with epoprostenol or other prostacyclin analogs for iPAH or PAH-SSc within 1 month before start of study treatment
  • Treatment with glibenclamide (glyburide), fluconazole ketoconazole or ritonavir within 1 week before start of study treatment.
  • Current treatment with cyclosporine A or tacrolimus
  • Hypersensitivity to bosentan or any of the excipients of its formulation.
  • Patient who received an investigational drug (such as sildenafil) within 3 months before start of study treatment
  • Conditions that prevent compliance with the protocol or adherence to therapy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: bosentan
Drug: bosentan
Bosentan 62.5 mg bid for 4 weeks, then 125 mg bid
Other Names:
  • Tracleer

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Change from baseline (BL) to 6 mths in the IVUS-derived measurement of pulmonary artery wall thickness.
Time Frame: Baseline to 6 months
Baseline to 6 months
Change from BL to 6 mths in pulmonary microvascular circulation dilator responses to actylcholine (Ach).
Time Frame: Baseline to 6 months
Baseline to 6 months

Secondary Outcome Measures

Outcome Measure
Time Frame
Change from BL to 6 mths in each of the IVUS derived pulmonary artery parameters.
Time Frame: Baseline to 6 months
Baseline to 6 months
Change from BL to 6 mths in pulmonary microvascular circulation dilator responses to sodium nitroprusside.
Time Frame: Baseline to 6 months
Baseline to 6 months
Correlation between the change from BL to 6 mths of each of the IVUS-derived parameters and the pulmonary microvascular circulation (PMVC) dilator responses versus changes in PVR.
Time Frame: Baseline to 6 months
Baseline to 6 months
Correlation between the change from BL to 6 mths of each of the IVUS-derived parameters and the PMVC dilator responses versus changes in 6MWD.
Time Frame: Baseline to 6 months
Baseline to 6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Actelion

Investigators

  • Principal Investigator: David Celermajer, Professor, Royal Prince Alfred Hospital, Camperdown

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 31, 2006

Primary Completion (Actual)

December 31, 2008

Study Completion (Actual)

June 30, 2010

Study Registration Dates

First Submitted

January 7, 2008

First Submitted That Met QC Criteria

January 7, 2008

First Posted (Estimated)

January 16, 2008

Study Record Updates

Last Update Posted (Actual)

June 3, 2026

Last Update Submitted That Met QC Criteria

June 1, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • AC-052-416

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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