Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruitingRare disease

Study on Fipaxalparant for Patients with Idiopathic Pulmonary Fibrosis

Fast replyInvestigationalNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

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

This clinical study is focused on a disease known as idiopathic pulmonary fibrosis (IPF), which is a condition where the lungs become scarred over time, making breathing increasingly difficult. The investigation involves using a medication called Fipaxalparant, known by the code name HZN-825, to assess its effectiveness, safety, and how well it is tolerated by individuals with IPF. IPF does not have a known cause, and this study aims to understand if this medication can help manage the disease.

The goal of the study is to test the impact of two different doses of HZN-825 compared to a placebo, over a 52-week period. Participants will take the medication in tablet form by mouth. The primary focus is to see if there are changes in lung function, specifically in a measure called forced vital capacity (FVC), which relates to how much air a person can forcefully exhale from their lungs after taking a deep breath. This measure is crucial as it can indicate the progression of lung conditions like IPF.

In addition to evaluating the lung capacity, other aspects such as safety and side effects of the treatment will be observed. The trial is structured in two parts; the initial phase involves a comparison with a placebo, and the subsequent extension phase continues to assess the medication's effectiveness over a longer period with open-label treatment, meaning that participants will know they are receiving the actual drug.

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

    Core Phase Initiation

    Upon joining the study, the participant begins the Core Phase, which lasts for 52 weeks.

    The primary goal is to evaluate the effectiveness of two different doses of the medication HZN-825 compared to a placebo.

    The participant will take the medication orally in the form of a film-coated tablet.

  2. Step 2

    Medication Administration

    The participant will receive HZN-825 or a placebo, depending on the group assignment.

    The medication is administered in a repeat-dose format, meaning it is taken regularly over the course of the study.

  3. Step 3

    Monitoring and Assessments

    Throughout the Core Phase, the participant's lung function will be monitored by 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.

    Additional assessments include the 6-minute walk test (6MWT) to evaluate exercise capacity, and questionnaires to assess quality of life and respiratory symptoms.

  4. Step 4

    Completion of Core Phase

    At the end of 52 weeks, the participant completes the Core Phase.

    The primary measurement is the change in FVC percentage from the beginning to the end of this phase.

  5. Step 5

    Extension Phase Initiation

    Participants who complete the Core Phase may enter the Extension Phase, which also lasts for 52 weeks.

    This phase is open-label, meaning all participants receive HZN-825 and no placebo is used.

  6. Step 6

    Continuation of Treatment

    During the Extension Phase, the participant continues to take HZN-825 as prescribed.

    The focus remains on assessing the long-term effectiveness and safety of the medication.

  7. Step 7

    Final Assessments

    At the end of the Extension Phase, the participant undergoes final assessments to measure changes in lung function and overall health status.

    The primary measurement is the change in FVC percentage from both the initial baseline and the start of the Extension Phase.

Who can join the trial?

14 criteria

  • You must provide written consent to participate.
  • You should be a male or female who is at least 18 years old.
  • You need to have a current diagnosis of Idiopathic Pulmonary Fibrosis (IPF), which is a lung condition, confirmed by specific guidelines.
  • Your initial diagnosis of IPF should have been made within the last 7 years.
  • If you are on IPF medication, your dose should be stable for at least 3 months before starting the trial, with no plans to change it during the trial.
  • If you are not currently on IPF medication, you should have stopped any previous IPF treatment at least 4 weeks before starting the trial, with no plans to restart it during the trial.
  • You must have a High-Resolution Computed Tomography (HRCT) scan of your lungs done within 6 months before the trial, showing specific patterns related to IPF.
  • Your HRCT scan should show between 10% and less than 50% lung fibrosis, which is a type of lung scarring, and more fibrosis than emphysema, a lung condition.
  • Your lung function tests during screening should meet these criteria:
    • Forced Vital Capacity (FVC), a measure of lung function, should be at least 45% of what is predicted as normal.
    • Forced Expiratory Volume in 1 second (FEV1)/FVC ratio should be at least 0.7.
    • Diffusing Capacity of the Lung for Carbon Monoxide (DLCO), corrected for hemoglobin, should be between 25% and 90% of what is predicted as normal.
    • You should have an estimated life expectancy of at least 30 months for conditions not related to IPF.
    • Your vaccinations should be up to date, based on your age, other health conditions, and local availability.
    • You must be willing and able to follow the treatment plan and attend evaluations throughout the trial.

Who cannot join the trial?

10 criteria

  • Patients who have a different lung condition other than Idiopathic Pulmonary Fibrosis (IPF) cannot participate. IPF is a disease that causes scarring of the lungs for an unknown reason.
  • Patients who are not within the specified age range for the study cannot participate. The age range is typically defined by the study but is not specified here.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have participated in another clinical trial recently may not be eligible to participate.
  • Patients with certain medical conditions that could interfere with the study results or pose a risk to the patient cannot participate.
  • Patients who are taking medications that could interfere with the study treatment cannot participate.
  • Patients who have a history of drug or alcohol abuse may not be eligible to participate.
  • Patients who have a known allergy to the study medication or its ingredients cannot participate.
  • Patients who have had a recent major surgery or are planning to have surgery during the study period may not be eligible to participate.
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

HZN-825 is a medication being studied for its potential to treat idiopathic pulmonary fibrosis (IPF). This condition causes scarring of the lungs, leading to breathing difficulties. The trial aims to evaluate how effective, safe, and tolerable HZN-825 is for patients with IPF. The study involves comparing the lung function of patients taking HZN-825 to those who do not, by measuring changes in their forced vital capacity (FVC) over a period of 52 weeks.

What is already known about the treatment

HZN-825 – HZN-825 is an investigational medication currently being studied for its potential to treat idiopathic pulmonary fibrosis, a lung disease that causes scarring of the lung tissue. It is administered orally in the form of tablets. The medication is in the clinical trial phase, specifically a Phase 2b study, to evaluate its efficacy, safety, and tolerability. The main therapeutic indication is to improve lung function by increasing the forced vital capacity in patients with idiopathic pulmonary fibrosis. At the molecular level, HZN-825 is believed to work by modulating certain pathways that contribute to tissue scarring and inflammation. It is classified pharmacologically as an anti-fibrotic agent.

Investigated diseases

Idiopathic Pulmonary Fibrosis – Idiopathic Pulmonary Fibrosis (IPF) is a chronic lung disease characterized by the progressive scarring of lung tissue. This scarring, or fibrosis, leads to a gradual decline in lung function, making it increasingly difficult for individuals to breathe. The exact cause of IPF is unknown, which is why it is termed "idiopathic." Over time, the thickened and stiff lung tissue hampers the ability of the lungs to transfer oxygen into the bloodstream. Symptoms often include a persistent dry cough and shortness of breath, especially during physical activity. As the disease progresses, individuals may experience fatigue and a decrease in exercise tolerance.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-509784-24-00Protocol codeHZNP-HZN-825-303Estimated enrolment153 patientsSponsorHorizon Therapeutics Ireland Designated Activity Company

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

ClinicalTrials.eu

Every clinical trial in Europe, in plain language.

Explore the full ecosystem of clinical research in Europe.

Search trials

Legal notice · Published by CTIN POLAND sp. z o.o., ul. rtm. Witolda Pileckiego 67/109, 02-781 Warsaw, Poland · KRS 0001111334 · REGON 528919042 · NIP 9512598637

© 2026 Clinical Trials EU – European Clinical Trials Information Network

GDPR compliance, ISO 9001 and ISO 27001 certified (LL-C Certification)

On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).