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Recruiting Phase 3 NCT05334368

NCT05334368 Depemokimab in Participants With Hypereosinophilic Syndrome, Efficacy, and Safety Trial

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Clinical Trial Summary
NCT ID NCT05334368
Status Recruiting
Phase Phase 3
Sponsor GlaxoSmithKline
Condition Hypereosinophilic Syndrome
Study Type INTERVENTIONAL
Enrollment 123 participants
Start Date 2022-09-06
Primary Completion 2028-12-19

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
DepemokimabPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 123 participants in total. It began in 2022-09-06 with a primary completion date of 2028-12-19.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This is a 52-week, randomized, placebo-controlled, double-blind, parallel group, multicenter study of depemokimab in adults with uncontrolled HES receiving standard of care (SoC) therapy. The study will recruit patients with a confirmed diagnosis of HES and who are on stable HES therapy for at least 4 weeks prior to randomization (Visit 2). Eligible participants must have uncontrolled HES with a history of repeated flare (≥2 flares in the previous 12 months) and blood eosinophil count of ≥1,000 cells/ microliter (μL) during Screening. Historical HES flares are defined as documented HES-related worsening of clinical symptoms or blood eosinophil counts requiring an escalation in therapy. Participants who meet the inclusion and exclusion criteria will be randomized in a 2:1 ratio to receive either depemokimab or placebo while continuing their SoC HES therapy.

Eligibility Criteria

Inclusion Criteria: * Participants who are greater than or equal (\>=) 40 kilogram (kg) at Screening Visit 1. * Participants who have a documented diagnosis of HES prior to Visit 2. * A history of 2 or more HES flares within the past 12 months prior to Visit 1. * A female participant is eligible to participate if she is not pregnant or breastfeeding, and one of the following conditions applies: a) woman of non-childbearing potential (WONCBP) Or b) woman of childbearing potential (WOCBP) and using a contraceptive method that is highly effective, with a failure rate of less than (\<) 1 percentage (%). * Capable of giving signed informed consent. Exclusion Criteria: * Participants with HES disease manifestations which in the opinion of the investigator may put the participant at unacceptable risk from study participation or confound interpretation of efficacy or safety data. * Participants with chronic or ongoing active infections requiring systemic treatment or a pre-existing parasitic infestation within 6 months prior to Visit 1. * Participants with a known immunodeficiency (e.g., Human Immunodeficiency Virus \[HIV\]), other than that explained by the use of OCS or other therapy taken for HES. * Participants with a history of or current lymphoma. * Participants with current malignancy or previous history of cancer in remission for less than 5 years prior to Visit 1. Participants that had localized carcinoma (i.e., basal or squamous cell) of the skin which was resected for cure will not be excluded. * Participants with a haematologic malignancy with hypereosinophilia in which HES is not the primary diagnosis, e.g., chronic myeloid leukaemia, myelodysplastic syndrome, chronic eosinophilic leukaemia-not otherwise specified. * Cirrhosis or current unstable liver or biliary disease per investigator assessment. * Participants who have severe or clinically significant cardiovascular disease uncontrolled with standard treatment. * Participants with current diagnosis of vasculitis. * Hypereosinophila with no clinical symptoms and/or proof of organ dysfunction. * Clinical diagnosis of Eosinophilic granulomatosis with polyangiitis (EGPA). * Participants with an allergy/ intolerance to a monoclonal antibody or biologic, or any of the excipients of the investigational product. * Participants who have a previous documented failure with anti-interleukin (IL)-5/5R therapy. * Participants who have received monoclonal antibodies (mAb) within 30 days or 5 half-lives, whichever is longer, prior to Visit 1. * Participants who test positive for the FIP1L1-PDGFRα fusion gene. * QT interval corrected for heart rate according to Fridericia's formula (QTcF) ≥450 milliseconds (msec) or QTcF ≥480 msec for participants with Bundle Branch Block at Screening Visit 1. * Participants who are not responsive to OCS based on clinical response or blood eosinophil counts in the opinion of the Investigator. * Participants who are pregnant or breastfeeding.

Contact & Investigator

Central Contact

US GSK Clinical Trials Call Center

✉ GSKClinicalSupportHD@gsk.com

📞 877-379-3718

Principal Investigator

GSK Clinical Trials

STUDY DIRECTOR

GlaxoSmithKline

Frequently Asked Questions

Who can join the NCT05334368 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Hypereosinophilic Syndrome. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05334368 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 123 participants.

Is NCT05334368 currently recruiting?

Yes, NCT05334368 is actively recruiting participants. Contact the research team at GSKClinicalSupportHD@gsk.com for enrollment information.

Where is the NCT05334368 trial being conducted?

This trial is being conducted at San Diego, United States, Atlanta, United States, Boston, United States, Southfield, United States and 11 additional locations.

Who is sponsoring the NCT05334368 clinical trial?

NCT05334368 is sponsored by GlaxoSmithKline. The principal investigator is GSK Clinical Trials at GlaxoSmithKline. The trial plans to enroll 123 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology