ClinicalTrials.gg
CompletedNCT05774184EvolvEUpdated May 27, 2026

A Study of CDX-0159 in Patients With Eosinophilic Esophagitis

A Phase 2 interventional study of barzolvolimab and Matching Placebo in Eosinophilic Esophagitis, sponsored by Celldex Therapeutics. Completed at 45 sites in 8 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-05-27.

Sponsored by Celldex Therapeutics · Phase 2, Interventional, and Treatment

From the registry’s dates

  • Primary completion was Jun 2025, 1 year 5 months ago, and no results have been posted to the registry; the sponsor requested a delay in submitting them in Apr 2026.
Phase
Phase 2
Study type
Interventional
Enrollment
86
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

The purpose of this study is to assess the efficacy and safety of barzolvolimab in adult Eosinophilic Esophagitis patients.

Read the detailed description

The purpose of this study is to assess the efficacy and safety of barzolvolimab in adult Eosinophilic Esophagitis patients.

02

Conditions studied

  • Eosinophilic Esophagitis

Keywords

  • barzolvolimab
  • esophagitis
  • EoE
  • mast cells
  • CDX-0159
03

In context

Eosinophilic Esophagitis

235 studies on the registry are indexed under Eosinophilic Esophagitis; 53 are open to participants now.

This study's enrollment of 86 is above the median of 42 across 134 interventional studies indexed under Eosinophilic Esophagitis.

Browse Eosinophilic Esophagitis studies →

Lead sponsor

Celldex Therapeutics is the lead sponsor of 45 studies on the registry; 3 are open to participants now.

Of its 14 completed or terminated interventional studies of FDA-regulated products, 1 (7%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Eligibility criteria

Key Inclusion Criteria

  1. ≥ 18 years of age
  2. Documented diagnosis of eosinophilic esophagitis (EoE) by endoscopy
  3. Peak esophageal intraepithelial eosinophil count (PEC) of ≥ 15 per high power field (hpf) from at least 2 of 3 levels (proximal, mid, and distal) of the esophagus
  4. Symptomatic, defined as • Average of ≥ 2 days per week with dysphagia with solid food intake in the 1 month prior to Screening, and • ≥ 4 days with dysphagia within the last 2 weeks prior to randomization
  5. On a stable diet which includes solid foods for ≥ 2 months prior to Screening (and throughout the study)
  6. Inadequate response to or is inappropriate for and/or intolerant to a standard-of-care treatment for EoE (e.g., PPI, swallowed topical , or dietary elimination)
  7. Willing to be compliant with completion of daily questionnaire

Key Exclusion Criteria

  1. Diagnosed with hypereosinophilic syndrome or Churg-Strauss syndrome (eosinophilic granulomatosis with polyangiitis)
  2. History of clinicopathologic diagnosis of eosinophilic gastritis or eosinophilic duodenitis
  3. Known active Helicobacter pylori infection
  4. History of coagulation disorders, esophageal varices, achalasia, Crohn's disease, ulcerative colitis, or celiac disease
  5. Esophageal dilation within 3 months prior to Screening
  6. Prior esophageal or gastric surgery that would confound the assessments of EoE
  7. Esophageal stricture that is difficult to pass with a standard adult upper endoscope (9 to 10 mm) or stricture that requires dilation at the Screening EGD
  8. Avoiding solid foods or using a feeding tube
  9. Regular use of antiplatelet and/or anticoagulant therapy
  10. Non-biologic systemic agents within 2 months prior to Screening, including but not limited to corticosteroid (oral, swallowed topical or parenteral), non-steroidal (e.g., methotrexate, cyclosporin, tacrolimus, mycophenolate mofetil, azathioprine), other immunomodulators (e.g., Jak inhibitors, tyrosine kinase inhibitors), and agents
  11. Biologic therapy within 5 half-lives (or detectable serum level) prior to Screening, including but not limited to interleukin (IL)-4 receptor inhibitor (dupilumab), IL-5 inhibitors (e.g., mepolizumab, benralizumab), IL-13 inhibitors (e.g., tralokinumab, lebrikizumab), anti-IgE (e.g., omalizumab), IFN-γ inhibitors, or other approved or investigational biologics
  12. Oral immunotherapy (OIT) within 6 months prior to Screening
  13. Sublingual immunotherapy (SLIT) and/or subcutaneous immunotherapy (SCIT) Note: Not exclusionary if patient has been on a stable maintenance dose for at least 6 months prior to Screening
  14. Receipt of a within 2 months prior to the Baseline (Day 1) Visit (patients must agree to avoid live vaccination during study treatment and within 3 months thereafter).
  15. Diagnosis of idiopathic anaphylaxis or other severe allergic reactions that in the opinion of the investigator, could increase the patient's risk for systemic reactions
  16. Prior receipt of barzolvolimab

There may be additional criteria your study doctor will review with you to confirm eligibility

Terms in these criteria, in plain language(5)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Live vaccines

Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
86 participants (actual)

Study arms

  • Active comparator
    Barzolvolimab (CDX-0159)

    300 mg subcutaneous administration every 4 weeks through week 24

    Biological: barzolvolimab

  • Placebo comparator
    Placebo then barzolvolimab (CDX-0159) 300mg

    Matching placebo subcutaneous administration every 4 weeks through week 16, then 300mg subcutaneous administration every 4 weeks through week 24

    Biological: barzolvolimab · Drug: Matching Placebo

Interventions

  • Biologicalbarzolvolimab

    subcutaneous administration

    Also known as: CDX-0159

  • DrugMatching Placebo

    subcutaneous administration

06

What researchers measure

Primary outcomes

  1. Absolute change from baseline to Week 12 in peak intraepithelial mast cell (PMC) count (PMC/hpf).

    Peak esophageal intraepithelial mast cell counts will be determined by counting mast cells in the most inflamed high-power field (hpf) of each of the 3 esophageal (proximal, mid, distal) levels and reported as mast cells/hpf.

    Time frame: From baseline to Visit 6 (Week 12)

Secondary outcomes

  1. Absolute changes from baseline to Week 12 in Dysphagia Symptom Questionnaire (DSQ).

    DSQ is a questionnaire designed to measure difficulty swallowing associated with Eosinophilic Esophagitis (EoE), with total scores ranging from 0 to 84; higher DSQ scores indicate worse symptoms.

    Time frame: From baseline to Visit 6 (Week 12)

  2. Absolute change from baseline to Week 12 in peak intraepithelial mast cell (PMC) count (PMC/hpf) among patients with baseline PMC ≥ 12/hpf.

    Peak esophageal intraepithelial mast cell counts will be determined by counting mast cells in the most inflamed high-power field (hpf) of each of the 3 esophageal (proximal, mid, distal) levels and reported as mast cells/hpf.

    Time frame: From baseline to Visit 6 (Week 12)

  3. Absolute change from baseline to Week 12 in Peak esophageal intraepithelial eosinophil count (PEC) (PEC/hpf).

    Peak esophageal intraepithelial eosinophils will be determined by counting eosinophils in the most inflamed high-power field (hpf) of each of the 3 esophageal (proximal, mid, distal) levels and reported as eosinophils/hpf.

    Time frame: From baseline to Visit 6 (Week 12)

  4. Percent (%) change from baseline to Week 12 in PMC/hpf.

    Peak esophageal intraepithelial mast cell counts will be determined by counting mast cells in the most inflamed high-power field (hpf) of each of the 3 esophageal (proximal, mid, distal) levels and reported as mast cells/hpf.

    Time frame: From baseline to Visit 6 (Week 12)

  5. Incidence of Treatment Emergent Adverse Events.

    The rates of treatment emergent adverse events will be summarized.

    Time frame: From first dose through Visit 14 (Week 44)

07

Study locations

45 sites
  • AllerVie Clinical Research
    Birmingham, Alabama 35209, United States
  • One of a Kind Clinical Research Center
    Scottsdale, Arizona 85258, United States
  • GI Alliance- Arizona Digestive Health- Sun City
    Sun City, Arizona 85351, United States
  • Del Sol Research Management, LLC
    Tucson, Arizona 85715, United States
  • GW Research Inc.
    Chula Vista, California 91910, United States
  • Connecticut Clinical Research Institute, LLC
    Bristol, Connecticut 06416, United States
  • ENCORE Borland Groover Clinical Research
    Jacksonville, Florida 32256, United States
  • Gastroenterology of Greater Orlando
    Orange City, Florida 32763, United States
  • Treasure Valley Medical Research
    Boise, Idaho 83706, United States
  • Northwestern University
    Chicago, Illinois 60208, United States
  • University of Iowa
    Iowa City, Iowa 52242, United States
  • University of Kansas Medical Center (KUMC)
    Kansas City, Kansas 66160, United States
  • Tandem Clinical Research
    Marrero, Louisiana 70072, United States
  • Boston Specialists - Boston Food Allergy Center
    Boston, Massachusetts 02111, United States
  • NYU Langone Health
    New York, New York 10016, United States
  • University of North Carolina (UNC) Hospitals
    Chapel Hill, North Carolina 27514, United States
  • Duke University Medical Center
    Durham, North Carolina 27710, United States
  • The Clinical Trials Network, LLC
    Willoughby, Ohio 44096, United States
  • The Pennsylvania State University (Penn State) Milton S. Hershey Medical Center
    Hershey, Pennsylvania 17033, United States
  • University of Pennsylvania
    Philadelphia, Pennsylvania 19104, United States
  • Vanderbilt University Medical Center-GI Clinical Research Program
    Nashville, Tennessee 37232, United States
  • Advanced Research Institute - Ogden
    Ogden, Utah 84405, United States
  • Care Access Research
    Salt Lake City, Utah 84124, United States
  • University of Utah
    Salt Lake City, Utah 84132, United States
  • Royal Adelaide Hospital
    Adelaide, South Australia, Australia
  • The Alfred Hospital
    Melbourne, Victoria, Australia
  • St Vincent's Hospital Melbourne
    Melbourne, Australia
  • University of Calgary
    Calgary, Alberta, Canada
  • PerCuro Clinical Research Ltd.
    Victoria, British Columbia, Canada
  • Universitaetsklinikum Augsburg
    Augsburg, Germany
  • Klinikum Region Hannover GmbH Burgwedel
    Hanover, Germany
  • Universitaetsklinikum Magdeburg A.oe.R.
    Magdeburg, Germany
  • IRCCS Ospedale San Raffaele
    Milan, Italy
  • Fondazione Policlinico Universitario A. Gemelli IRCCS - Universita Cattolica del Sacro Cuore
    Rome, Italy
  • Istituto Clinico Humanitas
    Rozzano, Italy
  • Azienda Ospedaliera Universitaria OO.RR. San Giovanni di Dio Ruggi d'Aragona-Plesso "Ruggi"
    Salerno, Italy
  • Azienda Ospedaliera - Universitaria Integrata di Verona - Ospedale Borgo Roma
    Verona, Italy
  • Centrum Medyczne Med-Gastr Sp. z o.o.
    Lodz, Poland
  • WIP Warsaw IBD Point Profesor Kierkus
    Warsaw, Poland
  • Wojskowy Instytut Medyczny - Panstwowy Instytut Badawczy, Klinika Gastroenterologii i Chorob
    Warsaw, Poland
  • Hospital General Universitario de Alicante Dr. Balmis
    Alicante, Spain
  • Hospital Clinico San Carlos
    Madrid, Spain
  • St George's Hospital
    London, United Kingdom
  • St. Thomas' Hospital
    London, United Kingdom
  • Norfolk and Norwich University Hospital
    Norwich, United Kingdom
08

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Jun 2023 to primary completion in Jun 2025, 24 months.

Of 24 phase 2 interventional studies under Eosinophilic Esophagitis, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 15 and three quarters within 28. This study's 24 months is close to that.

How these figures are worked out, and which studies are left out of them.

Registered
Mar 7, 2023
First posted
Mar 17, 2023
StartActual
Jun 1, 2023
Primary completionActual
Jun 4, 2025
CompletionActual
Jan 23, 2026
Results delay requested
Apr 28, 2026
Last update
May 27, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 27, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05774184
Responsible party
Sponsor
First posted
Mar 17, 2023
Start date
Jun 1, 2023
Primary completion
Jun 4, 2025
Completion
Jan 23, 2026
Last update
May 27, 2026

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.

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Discussion

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Studies of the drug tested here: Barzolvolimab

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