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Study on Macitentan for Children with Pulmonary Arterial Hypertension

Verified siteInvestigationalNo 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 pulmonary arterial hypertension in children. Pulmonary arterial hypertension is a condition where the blood pressure in the arteries of the lungs is higher than normal, which can make it difficult for the heart to pump blood through the lungs. The study will use a medication called macitentan, which is being tested to see how it works compared to the usual treatments for this condition. Macitentan is provided in a form that can be easily dissolved, making it suitable for children.

The purpose of the study is to understand how macitentan is processed in the body, as well as to evaluate its safety and effectiveness in treating children with pulmonary arterial hypertension. The study will involve children taking macitentan or receiving standard care, and their progress will be monitored over time. The study will also include a period where all participants will receive macitentan to gather more information about its long-term effects.

Participants will be observed for changes in their condition, including how well they can perform physical activities and their overall quality of life. The study will also track any hospitalizations related to pulmonary arterial hypertension and monitor the participants' health through regular check-ups. The trial is expected to continue until late 2025, providing valuable insights into the treatment of this condition in children.

The research process

The trial runs in 8 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, a signed informed consent by the parent(s) or legally designated representative is required. Additionally, assent from developmentally capable children is needed before any study procedures begin.

  2. Step 2

    Randomization

    Participants are randomly assigned to receive either the study medication, macitentan, or the standard of care treatment. This process ensures that each participant has an equal chance of receiving either treatment.

  3. Step 3

    Medication administration

    If assigned to the macitentan group, the medication is taken orally in the form of a dispersible tablet. The dosage and frequency are determined by the study team based on the participant's age and weight.

  4. Step 4

    Initial assessment

    Participants undergo an initial assessment to measure baseline health indicators. This includes checking the trough (pre-dose) plasma concentrations of macitentan and its active metabolite at specific weeks, depending on the participant's age.

  5. Step 5

    Ongoing monitoring

    Throughout the study, participants are monitored for safety and efficacy of the treatment. This includes regular health check-ups and assessments to track any changes in health status.

  6. Step 6

    End of core period

    The core period of the study concludes with a final assessment of the participant's health and response to the treatment. This includes measuring changes in physical activity, quality of life, and other health indicators.

  7. Step 7

    Extension period

    Participants may enter a single-arm extension period where they continue to receive the study medication. This phase allows for further assessment of the long-term effects of the treatment.

  8. Step 8

    Study completion

    Upon completion of the study, participants undergo a final evaluation to assess the overall impact of the treatment. This includes a review of all collected data and health outcomes.

Who can join the trial?

13 criteria

  • Signed informed consent by the parent(s) or legally designated representative, and agreement from children who are able to understand, before starting any study-related procedures.
  • Children who are 1 month to under 18 years old.
  • Children with a body weight of at least 3.5 kg at the time of joining the study.
  • Children with a confirmed diagnosis of pulmonary arterial hypertension (PAH) through a past procedure called right heart catheterization. This procedure measures the pressure in the lungs and heart.
  • Children with PAH that fits into specific categories, including those with Down Syndrome, and caused by:
    • Unknown reasons (idiopathic PAH)
    • Inherited reasons (heritable PAH)
    • Associated with congenital heart disease (CHD), which is a heart problem present at birth
    • Caused by drugs or toxins
    • Associated with HIV
    • Associated with connective tissue disease (PAH-aCTD)
    • Children who are in World Health Organization Functional Class I to III, which describes the severity of their condition.
    • Children who have not received PAH-specific treatment before, or those who are on one or two PAH-specific treatments.
    • Girls who can have children must have a negative pregnancy test before starting and during the study, and must agree to use a reliable method of birth control if they are sexually active.

Who cannot join the trial?

10 criteria

  • Patients with any other serious medical condition that might interfere with the study.
  • Patients who have had a recent surgery or are planning to have surgery during the study period.
  • Patients who are currently participating in another clinical trial.
  • Patients who have a known allergy to the study medication or its ingredients.
  • Patients who are unable to follow the study procedures or instructions.
  • Patients who have a history of non-compliance with medical treatments.
  • Patients who are pregnant or breastfeeding.
  • Patients with a history of drug or alcohol abuse.
  • Patients with certain heart conditions that are not stable.
  • Patients with severe liver or kidney disease.
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Investigated drugs

  • Macitentan

    is a medication used in this clinical trial to help treat children with pulmonary arterial hypertension, which is a condition where there is high blood pressure in the arteries that supply the lungs. This medication works by relaxing and widening the blood vessels, which can help lower the blood pressure in the lungs and improve the ability to exercise. The goal of using macitentan in this trial is to see how well it works and how safe it is for children with this condition.

  • Standard of Care

    refers to the regular treatment that is typically given to patients with pulmonary arterial hypertension. This can include a variety of medications and therapies that are commonly used to manage the condition and its symptoms. In this trial, the standard of care is used as a comparison to see how well macitentan performs against the usual treatments that children with this condition receive.

What is already known about the treatment

Macitentan – Macitentan is administered orally in the form of tablets and is currently being studied in clinical trials for its use in treating pediatric pulmonary arterial hypertension. This medication is already recognized in medical literature for its role in managing pulmonary arterial hypertension in adults, and the trial aims to evaluate its safety and effectiveness in children. Macitentan works by blocking certain receptors in the blood vessels, which helps to relax and widen them, reducing the pressure in the lungs. It is classified as an endothelin receptor antagonist, a type of drug that helps improve blood flow and reduce strain on the heart.

Investigated diseases

Pulmonary Arterial Hypertension – Pulmonary arterial hypertension is a condition characterized by high blood pressure in the arteries that supply the lungs. This disease causes the small arteries in the lungs to become narrow or blocked, leading to increased resistance to blood flow. As a result, the heart must work harder to pump blood through these arteries. Over time, this increased workload can lead to the enlargement and weakening of the heart. Symptoms often include shortness of breath, fatigue, dizziness, and swelling in the ankles or legs. The progression of the disease can vary, with symptoms gradually worsening over time.
Trial detailsLast updated 2 Oct 2026
Age0-17PhasePhase IIITrial ID2023-509845-10-00Protocol codeAC-055-312Estimated enrolment162 patientsSponsorActelion Pharmaceuticals Ltd.

sourced from the EU Clinical Trials Register and site verification

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