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Study on the Effectiveness and Safety of Barzolvolimab in Adults with Active Eosinophilic Esophagitis

Fast replyRegistered 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 eosinophilic esophagitis, a condition where a type of white blood cell called eosinophils builds up in the esophagus, leading to inflammation and difficulty swallowing. The study will evaluate the effectiveness and safety of a treatment called Barzolvolimab (CDX-0159), which is a humanized immunoglobulin G1 kappa monoclonal antibody. This treatment is designed to target and reduce the number of certain cells in the esophagus that contribute to the disease. Participants in the study will receive either Barzolvolimab or a placebo, which is a substance with no active medication, to compare the effects.

The purpose of the study is to assess how well Barzolvolimab works in reducing the number of specific cells in the esophagus and to ensure it is safe for use. The study will involve regular visits where participants will receive the treatment through subcutaneous injections, which means the medication is injected under the skin. The study will last for several weeks, during which participants will be monitored for any changes in their condition and any side effects they might experience.

In addition to Barzolvolimab, the study will also use epinephrine, commonly known as adrenaline, which is a chemical used in emergencies to treat severe allergic reactions. This is included as a precautionary measure. The study aims to provide valuable information on the potential benefits of Barzolvolimab for people with eosinophilic esophagitis, helping to improve treatment options for this condition.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit

    Upon joining the study, the initial visit involves a comprehensive evaluation to confirm eligibility. This includes a review of medical history and a physical examination.

    An endoscopy is performed to document the diagnosis of eosinophilic esophagitis and to assess the esophageal intraepithelial eosinophilic infiltration.

  2. Step 2

    Randomization

    Participants are randomly assigned to receive either the study medication, barzolvolimab, or a placebo. This process is double-blind, meaning neither the participant nor the study team knows which treatment is being administered.

  3. Step 3

    Treatment administration

    The study medication, barzolvolimab, is administered as a subcutaneous injection. The exact dosage and frequency are determined by the study protocol.

    Participants receiving the placebo will receive an injection that matches the appearance of the study medication.

  4. Step 4

    Follow-up visits

    Regular follow-up visits are scheduled to monitor the participant's health and response to the treatment. These visits include physical examinations and assessments of symptoms.

    Participants are required to report any side effects or changes in their condition during these visits.

  5. Step 5

    End of treatment evaluation

    At the end of the 12-week treatment period, a final evaluation is conducted. This includes another endoscopy to assess changes in the esophageal tissue.

    The primary goal is to measure the absolute change in peak esophageal intraepithelial mast cell count from baseline to week 12.

  6. Step 6

    Post-study follow-up

    After completing the treatment phase, participants may be asked to attend additional follow-up visits to monitor long-term effects and overall health.

Who can join the trial?

8 criteria

  • Must have read, understood, and provided written informed consent after the study has been fully explained.
  • Must be a male or female who is **18 years or older** at the time of signing the informed consent.
  • Must have a documented diagnosis of **Eosinophilic Esophagitis (EoE)**, which is a condition affecting the esophagus, confirmed by a procedure called endoscopy.
  • Must have **esophageal intraepithelial eosinophilic infiltration**, meaning a certain number of specific cells called eosinophils are present in the esophagus, with a count of **15 or more** per high power field in at least two out of three parts of the esophagus during a screening procedure.
  • Must be experiencing symptoms, specifically:
    • A history of having difficulty swallowing solid foods at least **two days per week** in the month before the screening visit.
    • At least **four days** with difficulty swallowing in the two weeks before starting the study.
    • Must have been on a **stable diet** that includes solid foods for at least **two months** before the screening visit and throughout the study. A stable diet means no major changes in food groups.
    • Must have had an inadequate response to, or be unsuitable for, or intolerant to standard treatments for EoE, such as **proton pump inhibitors (PPI)**, swallowed topical corticosteroids, or dietary changes, based on the doctor's judgment.

Who cannot join the trial?

10 criteria

  • Patients who have other serious health conditions that could interfere with the study.
  • Patients who are currently participating in another clinical trial.
  • Patients who have had a recent surgery or medical procedure that could affect the study results.
  • Patients who are unable to follow the study procedures or instructions.
  • Patients who have allergies or reactions to the study medication or similar medications.
  • Patients who are pregnant or breastfeeding.
  • Patients who have a history of substance abuse or addiction.
  • Patients who have certain infections that could affect the study.
  • Patients who have been diagnosed with certain types of cancer.
  • Patients who have a history of severe allergic reactions.
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Investigated drugs

Barzolvolimab (CDX-0159) is being studied for its potential to help adults with active eosinophilic esophagitis. This condition involves inflammation of the esophagus, often due to an increase in certain types of cells called mast cells. The medication aims to reduce the number of these mast cells in the esophagus, which may help alleviate symptoms and improve the condition.

What is already known about the treatment

Barzolvolimab – This medication is administered via injection and is currently being studied in clinical trials for its effectiveness in treating eosinophilic esophagitis, a condition characterized by inflammation of the esophagus. Barzolvolimab is in the investigational stage, with ongoing research to determine its safety and efficacy. It is primarily indicated for reducing the infiltration of mast cells in the esophagus, which are involved in the inflammatory process of this condition. At the molecular level, Barzolvolimab works by targeting specific pathways that regulate mast cell activity, aiming to decrease inflammation. It is classified pharmacologically as a monoclonal antibody, designed to modulate immune responses.

Investigated diseases

Eosinophilic Esophagitis – Eosinophilic Esophagitis is a chronic immune system disease where a type of white blood cell, called eosinophils, builds up in the lining of the esophagus. This accumulation is often a reaction to foods, allergens, or acid reflux and can lead to inflammation. Over time, the inflammation can cause the esophagus to become narrow, leading to difficulty swallowing and food impaction. Symptoms may include heartburn, chest pain, and regurgitation. The disease can affect people of all ages, but it is more common in males. It is often diagnosed in children and young adults.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-512767-30-00Protocol codeCDX0159-08Estimated enrolment75 patientsSponsorCelldex Therapeutics Inc.

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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).