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Study on the Effectiveness and Safety of Treprostinil and Drug Combination for Patients with Pulmonary Arterial Hypertension (Group I)

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a condition known as Pulmonary Arterial Hypertension (PAH), which is a type of high blood pressure that affects the arteries in the lungs and the right side of the heart. The study is investigating the effects of a treatment that includes a medication called treprostinil, which is given as a solution for infusion, meaning it is administered directly into the bloodstream. The purpose of the study is to compare the effectiveness and safety of an initial triple therapy, which includes treprostinil, with an initial double oral therapy in patients with PAH.

Participants in the study will be randomly assigned to receive either the triple therapy or the double oral therapy. The triple therapy consists of an oral endothelin receptor antagonist (ERA), an oral phosphodiesterase-5 inhibitor (PDE-5i), and parenteral treprostinil. The double oral therapy includes only the oral ERA and PDE-5i. The study will monitor participants over a period of time to assess their risk status and any changes in their condition. This will help determine how well the treatments work and their safety.

The study will last for a maximum of 720 days, during which participants will undergo various assessments to track their progress. These assessments will include checking heart and lung function and evaluating any side effects or adverse reactions to the treatments. The goal is to see if the triple therapy can help achieve a low-risk status in patients more effectively than the double oral therapy. Participants will be closely monitored to ensure their safety throughout the study.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the patient will have signed an informed consent form. This confirms understanding of the trial and agreement to participate.

    Eligibility is confirmed for patients aged 18 to 70 with a diagnosis of pulmonary arterial hypertension (PAH) and who have not received prior treatment for this condition.

  2. Step 2

    Initial assessment

    An initial assessment is conducted to evaluate the patient's health status. This includes a right heart catheterization to measure pressures in the heart and lungs.

    The assessment helps determine the patient's risk level and suitability for the trial.

  3. Step 3

    Treatment assignment

    Patients are randomly assigned to one of two treatment groups: triple therapy or double therapy.

    Triple therapy includes oral medications and a parenteral infusion of treprostinil, a medication administered through a solution for infusion.

  4. Step 4

    Medication administration

    For those in the triple therapy group, treprostinil is administered as a continuous infusion. The dosage is determined by the healthcare provider based on individual needs.

    The infusion is part of a combination with two oral medications: an endothelin receptor antagonist (ERA) and a phosphodiesterase-5 inhibitor (PDE-5i).

  5. Step 5

    Ongoing monitoring

    Patients undergo regular monitoring to assess the effectiveness and safety of the treatment. This includes follow-up visits and tests to measure heart and lung function.

    Monitoring continues throughout the trial period, which lasts up to 48 weeks.

  6. Step 6

    Evaluation of treatment response

    The primary goal is to achieve a low-risk status by the end of the trial. This is evaluated between weeks 24 and 48.

    If the treatment is not effective, adjustments may be made, or additional medications may be considered.

  7. Step 7

    Completion of the trial

    At the end of the trial, a final assessment is conducted to evaluate the overall health status and response to treatment.

    The trial aims to conclude by December 2027, with results contributing to understanding the effectiveness of the treatment strategies.

Who can join the trial?

16 criteria

  • Sign an informed consent form before any trial-related procedures. This means you agree to participate after understanding the study details.
  • Be a male or female aged between 18 and 70 years.
  • Have not received any treatment for **Pulmonary Arterial Hypertension (PAH)**, which is a type of high blood pressure affecting the lungs and heart.
  • Have a confirmed diagnosis of one of the following types of PAH:
    • **Idiopathic PAH (IPAH)**: PAH with no known cause.
    • **Heritable PAH (HPAH)**: PAH that runs in families.
    • PAH caused by drugs or toxins.
    • PAH linked to **Connective Tissue Disease**, which affects the tissues that support and connect different parts of the body.
    • PAH with corrected **congenital heart disease**, which is a heart defect present at birth that has been fixed.
    • Be at intermediate-high risk according to a specific risk assessment tool, or at intermediate-low risk with severe heart and lung function issues. This includes:
      • Mean right atrial pressure (RAP) of 20 mmHg or more.
      • Cardiac index (CI) less than 2.0 liters per minute.
      • Stroke volume index (SVI) less than 31 milliliters.
      • Pulmonary vascular resistance (PVR) of 12 Wood Units or more.
      • Undergo a **Right Heart Catheterization (RHC)**, a test to measure heart and lung pressures, with these results:
        • Mean pulmonary arterial pressure (mPAP) greater than 20 mmHg.
        • Pulmonary capillary wedge pressure (PCWP) of 15 mmHg or less.
        • PVR greater than 2 Wood Units.
        • If you are a woman who can become pregnant, you must not be pregnant or breastfeeding. You must take regular pregnancy tests and, if sexually active, agree to use reliable birth control methods until the study ends.

Who cannot join the trial?

10 criteria

  • Patients who are not diagnosed with pulmonary arterial hypertension (a type of high blood pressure that affects the arteries in the lungs and the right side of the heart).
  • Patients who are not within the specified age range for the study.
  • Patients who are part of a vulnerable population, which means they might need special protection or care.
  • Patients who cannot take the medications being tested in the study.
  • Patients who have other medical conditions that might interfere with the study.
  • Patients who are unable to follow the study procedures or attend the required visits.
  • Patients who are pregnant or breastfeeding.
  • Patients who have participated in another clinical trial recently.
  • Patients who have a history of drug or alcohol abuse.
  • Patients who have any other reason that the study doctors believe would make it unsafe or inappropriate for them to participate.
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Investigated drugs

  • Treprostinil

    is a medication used in this trial as part of a triple therapy approach. It is administered through an injection and helps to widen the blood vessels in the lungs, which can lower blood pressure and improve symptoms in patients with pulmonary arterial hypertension (PAH).

  • ERA (Endothelin Receptor Antagonist)

    is a type of oral medication used in both the triple and double therapy groups in this trial. It works by blocking the effects of endothelin, a substance in the blood that causes blood vessels to narrow. This helps to relax and widen the blood vessels, improving blood flow and reducing the workload on the heart.

  • PDE-5i (Phosphodiesterase-5 Inhibitor)

    is another oral medication included in both the triple and double therapy groups. It helps to relax blood vessels and improve blood flow by blocking the enzyme phosphodiesterase-5. This can help reduce the symptoms of PAH and improve exercise capacity.

What is already known about the treatment

Treprostinil – Treprostinil is administered parenterally, meaning it is given through injections or infusions. It is currently being studied in clinical trials for its effectiveness in treating pulmonary arterial hypertension (PAH), specifically in group I patients. The medication works by dilating blood vessels in the lungs, which helps to lower blood pressure and improve blood flow. Treprostinil is classified as a prostacyclin analogue, which means it mimics the action of a natural substance in the body that helps to widen blood vessels and prevent blood clots.

Investigated diseases

Pulmonary Arterial Hypertension (Group I) – This is a type of high blood pressure that affects the arteries in the lungs and the right side of the heart. It occurs when the small arteries in the lungs become narrowed or blocked, leading to increased resistance to blood flow. As a result, the heart must work harder to pump blood through the lungs, which can lead to heart enlargement and eventually heart failure. Symptoms often include shortness of breath, fatigue, dizziness, and swelling in the ankles or legs. The disease progresses as the pressure in the pulmonary arteries continues to rise, causing further strain on the heart. Over time, this can lead to a decline in physical ability and quality of life.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-504351-26-01Protocol codeTREV1-10P.401Estimated enrolment150 patientsSponsorAop Orphan Pharmaceuticals GmbH

sourced from the EU Clinical Trials Register and site verification

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