Hypereosinophilic SyndromePhase 3SPHERENCT04965636
Study in Pediatrics With HypEREosinophilic Syndrome (SPHERE)
A Phase 3 study testing Mepolizumab in people with Hypereosinophilic Syndrome, run by GlaxoSmithKline at 14 sites in 6 countries.
Trial summary
The purpose of this study is to investigate the efficacy and safety of mepolizumab in children and adolescents with hypereosinophilic syndrome (HES) who are receiving standard of care (SoC) therapy. Read more about this study
- Who is it for?
- Ages 6 to 17 years
- Conditions the study is for
- Hypereosinophilic Syndrome
- What is being tested?
- Mepolizumab
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 16 participants
- Where
- 14 sitesin 6 countries
- Study dates
- 14 Jul 2022to 28 Oct 2025
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 6 to 17 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Participant must be aged 6 to 17 years inclusive, at Screening (Visit 1).
- Participants who have been diagnosed with HES for at least 6 months prior to enrolment (Visit 2).
- A history of 2 or more HES flares within the past 12 months prior to Screening (Visit 1).
- Participants must have blood eosinophil count >=1000 cells per microliter (/mcL) present at Screening.
- Participants must be on a stable dose of HES therapy for the 4 weeks prior to the first dose of mepolizumab (Visit 2)
- Male and/or female
- Signed written informed consent
Who cannot join
- Life-threatening HES or life-threatening HES co-morbidities
- Other concurrent medical conditions that may affect the participant's safety
- Eosinophilia of unknown significance
- Fusion tyrosine kinase gene translocation [FIP1L1- Platelet-derived Growth Factor Receptor (PDGFRα) (F/P)] positivity
- Clinical diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA)
- Participants with chronic or ongoing active infections requiring systemic treatment, as well as participants who have experienced clinically significant infections due to viruses, bacteria, and fungi within 4 weeks prior to enrolment (Visit 2)
Show all 19Show fewer
- Participants with a pre-existing parasitic infestation within 6 months prior to enrolment (Visit 2)
- 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 documented history of any clinically significant cardiac damage prior to Screening (Visit 1) that, in the opinion of the investigator, would impact the participant's participation during the study
- Participants with a history of or current lymphoma, Participants with current malignancy or previous history of cancer in remission for less than 12 months prior to Screening (Visit 1)
- Participants who are not responsive to OCS based on clinical response or blood eosinophil counts.
- Participants who have previously received mepolizumab in the 4 months prior to enrolment (Visit 2)
- Participants receiving non-oral systemic corticosteroids in the 4-week period prior to enrolment (Visit 2).
- Participants who have received any other monoclonal antibodies within 30 days or 5 half-lives, whichever is longer, of enrolment (Visit 2).
- Participants who have received treatment with an investigational agent (biologic or non-biologic) within the past 30 days or 5 drug half-lives, whichever is longer, prior to enrolment (Visit 2).
- Use of candidate Coronavirus disease 2019 (COVID-19) vaccines that have not received limited, accelerated, or full authorization/approval, and are only in use as part of a clinical trial.
- Participants who are currently participating in any other interventional clinical study
- Participants with any history of hypersensitivity to any monoclonal antibody (including mepolizumab).
- Evidence of clinically significant abnormality in the hematological, biochemical, or urinalysis screen from the sample collected at Screening (Visit 1), that could put the participant's safety at risk by participating in the study, as judged by the investigator
Trial locations and contacts
14 sites in 6 countries.
14 sites in 6 countries
United States4 sites
GSK Investigational Site
Charleston, South Carolina, 29425
GSK Investigational Site
Cincinnati, Ohio, 45229
GSK Investigational Site
Cleveland, Ohio, 44106
GSK Investigational Site
Rochester, Minnesota, 55905
Argentina3 sites
GSK Investigational Site
Buenos Aires, 1888
GSK Investigational Site
Buenos Aires, C1028AAP
GSK Investigational Site
Quilmes, 1878
Turkey (Türkiye)3 sites
GSK Investigational Site
Ankara, 6230
GSK Investigational Site
Izmir, 35100
GSK Investigational Site
Kayseri, 38039
Brazil2 sites
GSK Investigational Site
São Paulo, 05410-002
GSK Investigational Site
Sorocaba, 18040-425
About this study
Official title: A Phase 3, 52-week, Open-label, Single Arm Study to Investigate the Efficacy and Safety of Mepolizumab SC in Participants Aged 6 to 17 Years With Hypereosinophilic Syndrome
The purpose of this study is to investigate the efficacy and safety of mepolizumab in children and adolescents with hypereosinophilic syndrome (HES) who are receiving standard of care (SoC) therapy.
- Conditions
- Hypereosinophilic Syndrome
- Being tested
- Mepolizumab
- Keywords
- Hypereosinophilic Syndrome, Mepolizumab, Safety, Efficacy, Pediatric, Adolescent
- Medical subject headings
- Hypereosinophilic Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MepolizumabDrug
Mepolizumab was provided in pre-filled safety syringe
| Study group | Role | What they receive |
|---|---|---|
| Mepolizumab 100 mg SC | Experimental | Participants in the age group of 6 to 11 years with body weight less than (<) 40 kilogram (kg) received Mepolizumab 100 milligram (mg) subcutaneous (SC) injection every 4 weeks over a treatment period of 52 weeks. Receives: Drug: Mepolizumab |
| Mepolizumab 300 mg SC | Experimental | Participants in the age group of 12 to 17 years received Mepolizumab 300 mg SC injection every 4 weeks over a treatment period of 52 weeks. Receives: Drug: Mepolizumab |
| Mepolizumab 200/100 mg SC | Experimental | A participant in the age group of 6 to 11 years with body weight greater than or equal to (>=) 40 kg received mepolizumab 200 mg SC injections every 4 weeks. During the conduct of the study, the mepolizumab dose was reduced to 100 mg SC injection every 4 weeks as body weight of the participant reduced to less than (<) 40 kg over a treatment period of 52 weeks. Receives: Drug: Mepolizumab |
| Mepolizumab 200/300 mg SC | Experimental | A participant in the age group of 6 to 11 years with body weight >=40 kg received mepolizumab 200 mg SC injections every 4 weeks. During the conduct of the study, the mepolizumab dose was increased to 300 mg SC injection every 4 weeks as age of the participant increased to the age group of 12 to 17 years over a treatment period of 52 weeks. Receives: Drug: Mepolizumab |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants Who Experienced HES Flares Over the 52-Week Study Treatment Period
A HES flare is defined as a HES related clinical manifestation based on a physician-documented change in clinical signs or symptoms (worsening symptoms and/or elevated blood eosinophil level) which resulted in need for either: an increase from the most recent dose in the maintenance Oral Corticosteroid (OCS) dose (prednisone/prednisolone equivalent) by at least 10 mg per day for 5 days or an increase in or addition of any immunosuppressive and/or cytotoxic HES therapy from/to the most recent dose of HES therapy. Data is presented by the number of HES flares (0, 1, 2, 3 ,4 and >=5) in the participants.
Measured: Up to Week 52
Secondary outcomes (9)
Change in Mean Daily Oral Corticosteroids (OCS) Dose (Prednisone/Prednisolone or Equivalent) for Each 4-week Period From Weeks 0-4 to Weeks 48-52
The mean daily OCS (prednisone or equivalent) dose for each 4-week period from Weeks 0-4 to Weeks 48-52 for each participant were calculated as the sum of the daily doses of OCS during each 4-week period divided by the total number of days. The change in the mean daily OCS dose for each 4-week period from Weeks 0-4 to Weeks 48-52 was calculated for each participant as the mean daily OCS dose for Weeks 48-52 minus the mean daily OCS dose for Weeks 0-4. Baseline value was derived as the sum of the daily doses of OCS during first 4 weeks following the initiation of mepolizumab treatment (Weeks 0-4) divided by total number of days. Change from Baseline was calculated as post-Baseline value minus Baseline Value.
Measured: Baseline (Weeks 0-4), Weeks 4-8, Weeks 8-12, Weeks 12-16, Weeks 16-20, Weeks 20-24, Weeks 24-28, Weeks 28-32, Weeks 32-36, Weeks 36-40, Weeks 40-44, Weeks 44-48 and Weeks 48-52
Number of Participants With Reduction of >=50 Percentage (%) in Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) for Each 4-week Period From Weeks 0-4 to Weeks 48-52
The mean daily OCS (prednisone or equivalent) dose for each 4-week period from Weeks 0-4 to Weeks 48-52 for each participant were calculated as the sum of the daily doses of OCS during each period divided by the total number of days. For each 4-week period, a reduction of 50% or more in mean OCS dose was defined as (mean OCS dose at each 4-week period minus mean OCS dose during Weeks 0-4) divided by (mean OCS dose during Weeks 0-4) multiplied by 100 was <= -50. Baseline value was derived as the sum of the daily doses of OCS during first 4 weeks following the initiation of mepolizumab treatment (Weeks 0-4) divided by total number of days.
Measured: Baseline (Weeks 0-4), Weeks 4-8, Weeks 8-12, Weeks 12-16, Weeks 16-20, Weeks 20-24, Weeks 24-28, Weeks 28-32, Weeks 32-36, Weeks 36-40, Weeks 40-44, Weeks 44-48 and Weeks 48-52
Number of Participants With a Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) of Less Than or Equal to (<=) 7.5 Milligrams (mg) During Weeks 48-52 in Subpopulation of Participants That Were Taking OCS at Baseline
The mean daily OCS (prednisone or equivalent) dose for Weeks 48-52 for each participant were calculated as the sum of the daily doses of OCS during this period divided by the total number of days. Number of participants with a mean daily OCS dose (prednisone/prednisolone or equivalent) of <=7.5 mg during period of Weeks 48-52 in subpopulation of participants that were taking OCS at Baseline has been presented.
Measured: Weeks 48-52
Number of Participants With a Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) of <=7.5 mg During Weeks 48-52 in Overall Population
The mean daily OCS (prednisone or equivalent) dose for Weeks 48-52 for each participant were calculated as the sum of the daily doses of OCS during this period divided by the total number of days. Number of participants with a mean daily OCS dose (prednisone/prednisolone or equivalent) of <=7.5 mg during period of Weeks 48-52 in overall population has been presented.
Measured: Weeks 48-52
Change From Baseline in Fatigue Severity Based on Weekly Average Score of Brief Fatigue Inventory (BFI) Item 3 (Worst Level of Fatigue During Past 24 Hours) for Week 52 for Participants in the Age Group of 12 to 17 Years
The BFI is a self-administered questionnaire developed to assess fatigue severity. The BFI has 9 items. BFI- Item 3 assesses the worst level of fatigue during the past 24 hours. Participants report their worst level of fatigue daily, for the previous 24 hours, using a numerical rating scale ranging from 0 (no fatigue) to 10 (as bad as you can imagine). The weekly average score of BFI item 3 was defined as the mean of the observed daily assessments over the 7-day period. The weekly average score of BFI item 3 ranges from 0 to 10, higher score indicates worst outcome. BFI Item 3 was assessed in the participants with the age group of 12 to 17 years at study entry. Baseline was defined as the mean of the 7 daily assessments of BFI item 3 up to but not including the date of first dose of study treatment. Change from Baseline was calculated as post-Baseline value minus Baseline Value.
Measured: Baseline (Week 0) and Week 52
Number of Participants With Any Time Post-Baseline Positive Anti-mepolizumab Antibodies (ADA)
Serum samples were collected for the determination of anti-mepolizumab antibodies (ADA) using a validated electro-chemiluminescent immunoassay. The assay involved screening, confirmation and titration assays. If serum samples tested positive in the screening assay, they were considered 'potentially positive' and were further analyzed for specificity using the confirmation assay. Samples that confirmed positive in the confirmation assay were reported as 'positive'. Confirmed positive ADA samples were further characterized in the titration assay to quasi-quantitate the amount of ADA in the sample and were also further characterized in the Neutralizing antibody (Nab) assay. A participant was considered positive ADA if they had at least one positive any time post-Baseline ADA result.
Measured: Up to Week 52
Number of Participants With Any Time Post-Baseline Positive Neutralizing Antibodies (NAb)
Blood samples were collected for the determination of positive neutralizing antibodies. NAb test was to be carried out on samples that were positive in the confirmatory binding antibody assay. A participant was to be considered positive for NAb if they had at least one positive any time post-Baseline neutralizing antibody result.
Measured: Up to Week 52
Ratio to Baseline in Blood Eosinophil Count
Blood samples were collected to measure eosinophil count. Ratio to Baseline is defined as post-dose visit value divided by Baseline value. Baseline was defined as the latest blood eosinophil value measured by the central laboratory prior to the first dose of study treatment.
Measured: Baseline (Week 0), Weeks 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48 and 52
Plasma Concentrations of Mepolizumab
Blood samples were collected at the indicated time points for pharmacokinetic analysis of Mepolizumab.
Measured: Pre-dose at Weeks 4 and 24; Week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jul 2021
- Study start14 Jul 2022
- Primary completion28 Oct 2025
- Study completion28 Oct 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Hypereosinophilic SyndromeStudies of the same condition, open and under way.
- More trials run by GlaxoSmithKlineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 16 participants (actual)
Sponsor and investigators
- Lead sponsor
- GlaxoSmithKline
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- GSK Clinical Trials, Study director, GlaxoSmithKline
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04965636
- Sponsor's protocol ID
- 215360
- Acronym
- SPHERE
- Status last verified
- Jul 2026
- First submitted
- 7 Jul 2021
- Last updated
- 6 Jul 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://d3l8i7lo48obsd.cloudfront.net/gsk-patient-level-data-sharing-july2025-1-Bgwa1UthxvluYbWYTThw.pdf
- Expanded access
- Available
Study at a glance
From the registry record, last updated by the sponsor on 6 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3, 52-week, Open-label, Single Arm Study to Investigate the Efficacy and Safety of Mepolizumab SC in Participants Aged 6 to 17 Years With Hypereosinophilic Syndrome
- ClinicalTrials.gov ID
- NCT04965636
- Acronym / sponsor ID
- SPHERE / 215360
- Conditions
- Hypereosinophilic Syndrome
- Keywords
- Hypereosinophilic Syndrome, Mepolizumab, Safety, Efficacy, Pediatric, Adolescent
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 16 participants (actual)
- Lead sponsor
- GlaxoSmithKlineIndustry (pharma, biotech, devices)
- Study start
- 14 Jul 2022 (actual)
- Primary completion
- 28 Oct 2025 (actual)
- Study completion
- 28 Oct 2025 (actual)
- First posted
- 16 Jul 2021 (actual)
- Results
- Posted 4 May 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to investigate the efficacy and safety of mepolizumab in children and adolescents with hypereosinophilic syndrome (HES) who are receiving standard of care (SoC) therapy.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Mepolizumab 100 mg SC | Experimental | Drug: MepolizumabParticipants in the age group of 6 to 11 years with body weight less than (<) 40 kilogram (kg) received Mepolizumab 100 milligram (mg) subcutaneous (SC) injection every 4 weeks over a treatment period of 52 weeks. |
| Mepolizumab 300 mg SC | Experimental | Drug: MepolizumabParticipants in the age group of 12 to 17 years received Mepolizumab 300 mg SC injection every 4 weeks over a treatment period of 52 weeks. |
| Mepolizumab 200/100 mg SC | Experimental | Drug: MepolizumabA participant in the age group of 6 to 11 years with body weight greater than or equal to (>=) 40 kg received mepolizumab 200 mg SC injections every 4 weeks. During the conduct of the study, the mepolizumab dose was reduced to 100 mg SC injection every 4 weeks as body weight of the participant reduced to less than (<) 40 kg over a treatment period of 52 weeks. |
| Mepolizumab 200/300 mg SC | Experimental | Drug: MepolizumabA participant in the age group of 6 to 11 years with body weight >=40 kg received mepolizumab 200 mg SC injections every 4 weeks. During the conduct of the study, the mepolizumab dose was increased to 300 mg SC injection every 4 weeks as age of the participant increased to the age group of 12 to 17 years over a treatment period of 52 weeks. |
Who may qualify
- Ages
- 6 to 17 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (7 listed)
- Participant must be aged 6 to 17 years inclusive, at Screening (Visit 1).
- Participants who have been diagnosed with HES for at least 6 months prior to enrolment (Visit 2).
- A history of 2 or more HES flares within the past 12 months prior to Screening (Visit 1).
- Participants must have blood eosinophil count >=1000 cells per microliter (/mcL) present at Screening.
- Participants must be on a stable dose of HES therapy for the 4 weeks prior to the first dose of mepolizumab (Visit 2)
Key exclusion criteria (19 listed)
- Life-threatening HES or life-threatening HES co-morbidities
- Other concurrent medical conditions that may affect the participant's safety
- Eosinophilia of unknown significance
- Fusion tyrosine kinase gene translocation [FIP1L1- Platelet-derived Growth Factor Receptor (PDGFRα) (F/P)] positivity
- Clinical diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| MepolizumabMepolizumab was provided in pre-filled safety syringe | Drug | Mepolizumab 100 mg SC, Mepolizumab 200/100 mg SC, Mepolizumab 200/300 mg SC, Mepolizumab 300 mg SC |
Primary outcome
Number of Participants Who Experienced HES Flares Over the 52-Week Study Treatment Period
Time frame: Up to Week 52
A HES flare is defined as a HES related clinical manifestation based on a physician-documented change in clinical signs or symptoms (worsening symptoms and/or elevated blood eosinophil level) which resulted in need for either: an increase from the most recent dose in the maintenance Oral Corticosteroid (OCS) dose (prednisone/prednisolone equivalent) by at least 10 mg per day for 5 days or an increase in or addition of any immunosuppressive and/or cytotoxic HES therapy from/to the most recent dose of HES therapy. Data is presented by the number of HES flares (0, 1, 2, 3 ,4 and >=5) in the participants.
9 secondary outcomes
Change in Mean Daily Oral Corticosteroids (OCS) Dose (Prednisone/Prednisolone or Equivalent) for Each 4-week Period From Weeks 0-4 to Weeks 48-52
Time frame: Baseline (Weeks 0-4), Weeks 4-8, Weeks 8-12, Weeks 12-16, Weeks 16-20, Weeks 20-24, Weeks 24-28, Weeks 28-32, Weeks 32-36, Weeks 36-40, Weeks 40-44, Weeks 44-48 and Weeks 48-52
Number of Participants With Reduction of >=50 Percentage (%) in Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) for Each 4-week Period From Weeks 0-4 to Weeks 48-52
Time frame: Baseline (Weeks 0-4), Weeks 4-8, Weeks 8-12, Weeks 12-16, Weeks 16-20, Weeks 20-24, Weeks 24-28, Weeks 28-32, Weeks 32-36, Weeks 36-40, Weeks 40-44, Weeks 44-48 and Weeks 48-52
Number of Participants With a Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) of Less Than or Equal to (<=) 7.5 Milligrams (mg) During Weeks 48-52 in Subpopulation of Participants That Were Taking OCS at Baseline
Time frame: Weeks 48-52
Number of Participants With a Mean Daily OCS Dose (Prednisone/Prednisolone or Equivalent) of <=7.5 mg During Weeks 48-52 in Overall Population
Time frame: Weeks 48-52
Change From Baseline in Fatigue Severity Based on Weekly Average Score of Brief Fatigue Inventory (BFI) Item 3 (Worst Level of Fatigue During Past 24 Hours) for Week 52 for Participants in the Age Group of 12 to 17 Years
Time frame: Baseline (Week 0) and Week 52
Number of Participants With Any Time Post-Baseline Positive Anti-mepolizumab Antibodies (ADA)
Time frame: Up to Week 52
Number of Participants With Any Time Post-Baseline Positive Neutralizing Antibodies (NAb)
Time frame: Up to Week 52
Ratio to Baseline in Blood Eosinophil Count
Time frame: Baseline (Week 0), Weeks 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48 and 52
Plasma Concentrations of Mepolizumab
Time frame: Pre-dose at Weeks 4 and 24; Week 52
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jul 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://d3l8i7lo48obsd.cloudfront.net/gsk-patient-level-data-sharing-july2025-1-Bgwa1UthxvluYbWYTThw.pdf
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
GSK Clinical Trials study director
GlaxoSmithKline
14 sites in 6 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Mepolizumab in people with Hypereosinophilic Syndrome, run by GlaxoSmithKline at 14 sites in 6 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 14 sites in United States, Argentina, Turkey (Türkiye), Brazil, Israel and 1 more country. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 4 May 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants Who Experienced HES Flares Over the 52-Week Study Treatment Period (time frame: Up to Week 52). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jul 2026.