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Study on the Effects of Inhaled Treprostinil for Patients with Progressive Pulmonary Fibrosis

Fast replyInvestigationalNo 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 lung disease called Progressive Pulmonary Fibrosis (PPF). PPF is a condition where the lungs become scarred over time, making it difficult to breathe. The study will test a treatment called Treprostinil, which is given as a solution to be inhaled using a nebulizer. A nebulizer is a device that turns liquid medicine into a mist, making it easier to breathe in. The study will compare the effects of Treprostinil with a placebo, which looks like the real treatment but does not contain the active drug.

The purpose of the study is to see if inhaled Treprostinil can improve lung function in people with PPF over a period of 52 weeks, which is about one year. Participants will be randomly assigned to receive either Treprostinil or the placebo, and neither the participants nor the researchers will know who is receiving which treatment. This is known as a double-blind study. Throughout the study, participants will have regular check-ups to monitor their lung function and overall health.

Participants will be observed for any changes in their condition, including lung function and symptoms, as well as any side effects from the treatment. The study will also look at how long it takes for any worsening of the disease to occur and will track overall survival rates. The goal is to determine if Treprostinil can help slow down the progression of PPF and improve the quality of life for those affected by this condition.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes a review of medical history and current health status.

    A high-resolution computed tomography (HRCT) scan is used to verify the extent of pulmonary fibrosis, which must be greater than 10%.

  2. Step 2

    Baseline measurements

    Baseline measurements are taken to establish a starting point for the study. This includes measuring the forced vital capacity (FVC), which is the amount of air that can be forcibly exhaled from the lungs after taking the deepest breath possible.

    Other baseline assessments include blood tests, vital signs, and a 12-lead electrocardiogram.

  3. Step 3

    Randomization and treatment

    Participants are randomly assigned to receive either the inhaled treprostinil or a placebo. The study is double-blind, meaning neither the participants nor the researchers know who receives the active treatment.

    The medication is administered via inhalation using a nebulizer. The dosage and frequency are determined by the study protocol.

  4. Step 4

    Ongoing assessments

    Regular assessments are conducted throughout the study to monitor health and response to treatment. These include measuring changes in FVC at weeks 16, 28, 40, and 52.

    Additional assessments include monitoring for any adverse events, changes in respiratory symptoms, and overall survival.

  5. Step 5

    Final evaluation

    At the end of the 52-week study period, a final evaluation is conducted. This includes a comprehensive review of all collected data, including changes in FVC, respiratory symptoms, and any adverse events experienced during the study.

    The results are used to determine the efficacy and safety of the inhaled treprostinil treatment.

Who can join the trial?

15 criteria

  • The person must give their voluntary informed consent to join the study. This means they agree to participate after understanding what the study involves.
  • The study doctor believes the person can communicate well with the study team and will follow the study rules, including attending all study visits.
  • The person must be at least 18 years old when they sign the consent form.
  • The person must have a scan showing more than 10% of their lungs affected by fibrosis, which is a type of lung scarring, in the past 12 months.
  • The person must have a diagnosis of **Progressive Pulmonary Fibrosis (PPF)**, which is a type of lung disease, and meet at least one of the following conditions for worsening within 24 months despite standard treatment:
    • A significant drop in lung function, measured by a test called **FVC** (Forced Vital Capacity), by 10% or more.
    • A smaller drop in FVC by 5% to less than 10%, along with worsening breathing symptoms.
    • A smaller drop in FVC by 5% to less than 10%, along with more lung scarring seen on chest images.
    • Worsening breathing symptoms and more lung scarring seen on chest images.
    • The person's FVC must be at least 45% of what is predicted for their age and size at the start of the study.
    • The person must be on one of the following treatments:
      • Taking **nintedanib** or **pirfenidone** for at least 90 days before the study starts and planning to continue during the study.
      • Not taking nintedanib or pirfenidone for at least 90 days before the study starts and not planning to start during the study.
      • If the person is taking medications that suppress the immune system, like mycophenolate or methotrexate, they must have been on these for at least 120 days before the study starts and not responding to them.
      • Women who can have children must not be pregnant or breastfeeding and must agree to:
        • Not have sexual intercourse, if this is their usual lifestyle.
        • Use two highly effective forms of birth control during the study and for at least 30 days after stopping the study drug. These can include hormonal contraceptives or barrier methods like condoms.
        • Men with partners who can have children must agree to use a condom during treatment and for at least 48 hours after stopping the study drug.

Who cannot join the trial?

8 criteria

  • Patients with other serious lung diseases that are not related to Progressive Pulmonary Fibrosis (PPF) cannot participate. PPF is a condition where the lungs become scarred over time, making it hard to breathe.
  • Individuals who have had a recent lung infection or illness that affects their breathing may be excluded.
  • People who have had a recent surgery or are planning to have surgery during the study period might not be eligible.
  • Participants who are currently taking certain medications that could interfere with the study treatment may be excluded.
  • Individuals with a history of severe allergic reactions to similar medications may not be able to join the study.
  • Pregnant or breastfeeding women are typically not allowed to participate in clinical trials to ensure the safety of the mother and child.
  • Patients with certain heart conditions that could be worsened by the study treatment may be excluded.
  • Individuals who are unable to follow the study procedures or attend regular check-ups may not be eligible.
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Investigated drugs

Treprostinil is a medication used in this study to help people with progressive pulmonary fibrosis. It is inhaled, which means you breathe it in, and it works by helping to improve blood flow in the lungs. This can help make breathing easier and improve lung function over time. The study aims to see how well this medication works compared to not using it.

What is already known about the treatment

Treprostinil – Treprostinil is administered through inhalation, allowing the medication to directly reach the lungs. It is currently being studied in a Phase 3 clinical trial for its effectiveness and safety in treating progressive pulmonary fibrosis. The main therapeutic indication for treprostinil in this trial is to improve lung function in individuals with this condition. At the molecular level, treprostinil works by dilating blood vessels in the lungs, which helps to reduce blood pressure and improve oxygen flow. It is classified pharmacologically as a prostacyclin analog, 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

Progressive Pulmonary Fibrosis – This is a lung disease characterized by the gradual scarring of lung tissue, which leads to a decline in lung function over time. The scarring, or fibrosis, makes it difficult for the lungs to work properly, reducing the ability to breathe deeply. As the disease progresses, individuals may experience increasing shortness of breath, a persistent dry cough, and fatigue. The condition can lead to a decrease in the amount of oxygen that reaches the bloodstream, affecting overall health. The progression of the disease varies among individuals, with some experiencing a slow decline and others a more rapid deterioration.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-504904-26-00Protocol codeRIN-PF-305Estimated enrolment725 patientsSponsorUnited Therapeutics Corp.

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