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Access to Mepolizumab for Patients with Hypereosinophilic Syndrome

Investigational
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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 providing access to a treatment for individuals with Hypereosinophilic Syndrome (HES). HES is a condition characterized by an abnormally high number of eosinophils, a type of white blood cell, which can lead to damage in various organs. The treatment being studied is called Mepolizumab, which is administered as a solution for injection under the skin. Mepolizumab is designed to help manage the symptoms of HES by targeting and reducing the number of eosinophils in the body.

The purpose of this study is to offer expanded access to Mepolizumab for patients who have a significant medical need and for whom the potential benefits of the treatment outweigh the risks. This program is available in certain countries where regulatory authorities permit it. The study involves regular administration of Mepolizumab, and participants will be monitored by healthcare professionals to ensure their safety and well-being throughout the treatment period.

Participants in this study will receive Mepolizumab injections and will be closely observed by their healthcare provider. The healthcare provider will use their clinical judgment to determine if Mepolizumab is suitable for the patient, based on the information provided in the Investigator's Brochure, which contains detailed information about the drug. The study aims to ensure that patients with HES who have not responded to other treatments can access Mepolizumab as a potential option for managing their condition.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Participation begins after providing written informed consent or assent, which may be obtained from the patient or a legally authorized representative.

    Eligibility requires being at least 12 years old and meeting specific diagnostic criteria for hypereosinophilic syndrome (HES).

  2. Step 2

    Treatment administration

    The treatment involves the administration of mepolizumab, a medication provided as a solution for injection.

    Mepolizumab is administered through subcutaneous injection, which means it is injected under the skin.

    The dosage and frequency of administration are determined by the investigator based on clinical judgment and the patient's specific needs.

  3. Step 3

    Monitoring and assessment

    Throughout the trial, the investigator monitors the patient's response to the treatment and any side effects.

    The primary focus is on serious adverse events (SAEs) and non-serious adverse events related to mepolizumab, as assessed by the investigator.

    The mean 28-day subcutaneous dose for the last three administrations is also evaluated.

  4. Step 4

    Trial duration

    The estimated end date for the trial is March 30, 2025.

    The trial began recruiting participants on March 20, 2019.

Who can join the trial?

6 criteria

  • The patient or their legal representative must provide written permission to participate, following local rules.
  • The patient must be at least 12 years old when giving permission to participate.
  • The patient must have a diagnosis of Hypereosinophilic Syndrome (HES). This means having a high number of a type of white blood cell called eosinophils (more than 1500 cells per microliter) for at least 6 months, along with symptoms affecting organs, and no other known causes like allergies or infections. If the high eosinophil count is for less than 6 months, there must be clear signs of these cells affecting tissues, and other causes must be ruled out.
  • The patient must meet all three of these conditions:
    • HES is a serious or life-threatening condition.
    • There are no other good treatment options, meaning the patient has tried at least three standard treatments (like certain medications) without success or has benefited from the study drug before.
    • There is a belief that the benefits of the study drug outweigh the risks for the patient.

Who cannot join the trial?

1 criterion

  • There are no specific exclusion criteria listed for this clinical trial.
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Investigated drugs

Mepolizumab is a medication used in this trial to help people with hypereosinophilic syndrome, a condition where there are too many eosinophils, a type of white blood cell, in the body. This medication works by targeting and reducing the number of eosinophils, which can help alleviate symptoms and prevent complications associated with the syndrome. The trial aims to provide access to this medication for patients who have a clear medical need and where the potential benefits outweigh the risks.

What is already known about the treatment

Mepolizumab – Mepolizumab is administered as an injection under the skin, typically in a healthcare setting. It is currently available through an expanded access program for patients with hypereosinophilic syndrome, a condition characterized by high levels of eosinophils, a type of white blood cell. The medication works by targeting and blocking interleukin-5 (IL-5), a protein that plays a key role in the growth and activity of eosinophils, thereby reducing their numbers and activity. Mepolizumab is classified as a monoclonal antibody and is used primarily for its anti-inflammatory effects in conditions with elevated eosinophils.

Investigated diseases

Hypereosinophilic Syndrome – This is a rare condition characterized by an abnormally high number of eosinophils, a type of white blood cell, in the blood. The excess eosinophils can infiltrate various tissues and organs, leading to inflammation and damage. Symptoms can vary widely depending on which organs are affected, but may include skin rashes, respiratory issues, and gastrointestinal problems. Over time, the persistent presence of high eosinophil levels can lead to chronic organ dysfunction. The exact cause of hypereosinophilic syndrome is often unknown, but it may be associated with genetic mutations or other underlying conditions. The progression of the disease can be slow or rapid, and it requires careful monitoring to manage symptoms and prevent complications.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-515247-28-00Protocol code104317Estimated enrolment15 patientsSponsorGlaxosmithkline Research & Development Limited

sourced from the EU Clinical Trials Register and site verification

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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).