DysphagiaNCT07027826
The Esophageal String Test as a Diagnostic Screening Tool for Eosinophilic Esophagitis Among Africans With Dysphagia in Mali and the United States
A study testing Esophageal string test in people with Dysphagia and Eosinophilic Esophagitis, run by National Institute of Allergy and Infectious Diseases (NIAID) at 3 sites in 2 countries.
Trial summary
Background: Eosinophilic esophagitis (EoE) is a disease that causes inflammation in the esophagus. The esophagus is the tube that moves food from the mouth to the stomach. Diagnosing EoE currently requires a specialized tool called an endoscope. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Dysphagia, Eosinophilic Esophagitis
- What is being tested?
- Esophageal string test
- Type of treatment
- Pill or oral medicine, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 70 participants
- Where
- 3 sitesin 2 countries
- Study dates
- 28 Oct 2026to 31 Aug 2027
- Phase
- Interventional
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 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Able to provide informed consent.
- Aged 18 to 65 years.
- Born in the African continent or their parents were born in Africa,
- Exhibiting symptoms of dysphagia and/or prior history of food impaction.
- Undergoing clinically indicated endoscopy at the NIH Clinical Center (U.S.), Centre Hospitalier Universitaire Gabriel Tour(SqrRoot)(Copyright) (Mali), or other local clinics (Mali) and willing to provide research samples and data.
Who cannot join
- An individual who meets any of the following criteria will be excluded from participation in this study:
- Recent steroid use (systemic or swallowed/topical corticosteroid) within 4 weeks prior to endoscopy.
- Recent use of dupilumab (Dupixent) within the last 6 months.
- Recent use of other biologic medications (within either 6 months or 5 half-lives, whichever is longer). Examples of biologic medications include:
- 3a. mepolizumab (Nucala)
- 3b. reslizumab (Cinqair, Cinqaero)
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- 3c. benralizumab (Fasenra)
- 3d. cendakimab
- 3e. tezepelumab (Tezspire)
- 3f. barzolvolimab
- 4. Individuals suffering from a bleeding diathesis (e.g., hemophilia, severe thrombocytopenia).
- 5. Current use of anticoagulant medications.
- 6. Pregnancy.
- 7. Treatment with another investigational drug or other investigational intervention within 6 months or 5 half-lives whichever is longer.
- 8. Individuals with a known history of any of the following:
- 8a. eosinophilic esophagitis
- 8b. esophageal stricture unable to be passed with an upper endoscope
- 8c. esophageal cancer
- 8d. esophageal motility disorder (e.g., achalasia)
- 8e. esophageal varices
- 8f. esophageal or gastric surgery including fundoplication
- 8g. neurologic cause of dysphagia (e.g., stroke, Parkinson s disease, etc.)
- 8h. allergy to gelatin
- 8i. inability to swallow pills
- 9. Any condition that, in the investigator s opinion, places the individual at undue risk by participating in the study.
- Co-enrollment guidelines: Co-enrollment in other trials is restricted, other than enrollment on observational studies. Consideration for co-enrollment in trials evaluating the use of a licensed medication will require the approval of the principal investigator in consultation with the medical monitor. Study staff should be notified of co-enrollment on any other protocol as it may require the approval of the principal investigator.
Trial locations and contacts
3 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
3 sites in 2 countries
Mali2 sites, 2 recruiting
- Not yet recruiting
Gabriel Toure University Hospital Center
Bamako
Yaya Coulibaly, 223-79-24-44-64, yicoulibaly@icermali.org
- Not yet recruiting
Mali International Center for Excellence in Research
Bamako
Yaya Coulibaly, M.D., (223) 792-4446, yicoulibaly@icermali.org
United States1 site, 1 recruiting
- Recruiting
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892
Perla Adames Castillo, B.S.N., 301-402-8495, perla.adamescastillo@nih.gov
Gregory Constantine, M.D., (301) 633-6453, gregory.constantine@nih.gov
About this study
Official title: Use of the Esophageal String Test as a Diagnostic Screening Tool for Eosinophilic Esophagitis Among Africans With Dysphagia in Mali and the United States
Background:
Eosinophilic esophagitis (EoE) is a disease that causes inflammation in the esophagus. The esophagus is the tube that moves food from the mouth to the stomach. Diagnosing EoE currently requires a specialized tool called an endoscope. The esophageal string test (EST) is another test; the EST collects fluid from the upper digestive tract. An EST is simpler and cheaper than an endoscopy. Researchers want to know if an EST can diagnose EoE.
Read more
Objective:
To test if the EST can diagnose EoE in people who have trouble swallowing.
Eligibility:
Adults aged 18 to 65 years with trouble swallowing. They must have been born in the African continent or their parents were born in Africa.
Design:
Participants will be screened. They will give blood, stool, urine, and skin swab samples. They will complete surveys about their medical history, diet, symptoms, and home environment. They will bring a sample of their drinking water for testing.
Participants will have an EST. They will swallow a pill capsule that contains a nylon string. One end of the string will be taped to their cheek. The string will unravel down the esophagus and into the stomach. It will be pulled out after 1 hour. Fluids that soaked into the string will be tested.
At a different visit, participants will have an endoscopic exam. An endoscope is a flexible tube that is inserted down the mouth; it can be used to take tissue samples from the esophagus, stomach, and small intestine.
Participants will have a final visit in person, online, or by phone. They will take a survey and talk about their test results.
Read the detailed description
Study Description:
Eligible participants will be enrolled to assess the performance and accuracy of the 1-hour esophageal string test (EST) as a diagnostic screening tool for eosinophilic esophagitis (EoE). Consenting participants in the U.S. (n=30) and Mali (n=30) undergoing clinically indicated esophagogastroduodenoscopy (EGD) will have an EST performed prior to the procedure. Clinical data, including medical history and laboratory test results, will be captured on a case report form. Symptoms will also be assessed using validated patient reporting outcome measures: the Brief Esophageal Dysphagia Questionnaire (BEDQ) and Patient-Reported Outcomes Measurement Information System (PROMIS-GI and -57). Dietary, sociodemographic, and environmental histories will be obtained by validated questionnaires. Blood, urine, stool, and skin swab/tape strip samples will be obtained for additional biomarker studies.
Participants will be screened for intestinal helminth infections by stool polymerase chain reaction (PCR). Tissue samples obtained during EGD will be assessed for Helicobacter pylori by histopathology. Esophageal biopsy samples and remaining EST eluents will be allocated for investigational studies. Air and water samples will be collected from areas within the participants community and analyzed to determine potential correlation with elevated levels of environmental pollutants. The hypothesis of this study is that the 1-hour EST will provide a preliminary estimate of EoE prevalence among Africans and African immigrants presenting with dysphagia.
Primary Objective:
-Assess the accuracy of the 1-hour EST as a diagnostic screening tool for EoE among African individuals presenting with dysphagia in the U.S. and Mali.
Secondary Objective:
-Determine the frequency of EoE among African individuals presenting with dysphagia in the U.S. and Mali.
Primary Endpoint(s):
- Sensitivity, as estimated by the proportion of positive EST-obtained EoE-Score(TM) results out of those diagnosed with EoE by the gold standard of esophageal biopsy.
- Specificity, as estimated by the proportion of negative EST-obtained EoE-Score(TM) results out of those diagnosed with EoE by the gold standard of esophageal biopsy.
Secondary Endpoints:
-Proportion of EoE cases diagnosed in each cohort.
- Conditions
- Dysphagia, Eosinophilic Esophagitis
- Being tested
- Esophageal string test
- Keywords
- Eosinophilic Esophagitis, Dysphagia, Esophageal string test
- Medical subject headings
- Deglutition Disorders, Eosinophilic Esophagitis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Esophageal string testDevice
The esophageal string test consists of a gelatin or cellulose capsule containing a nylon string. The capsule dissolves allowing the nylon string to absorb esophageal secretions which can be analyzed for various inflammatory mediators.
| Study group | Role | What they receive |
|---|---|---|
| Esophageal string test | Experimental | The esophageal string test is a minimally invasive procedure used to collect esophageal secretions for diagnostic analysis. Receives: Device: Esophageal string test |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sensitivity and specificity of the esophageal string test to detect Eosinophilic Esophagitis.
Assess the accuracy of the 1-hour EST as a diagnostic screening tool for EoE in populations with limited access to subspecialty care. Sensitivity and specificity provide a measure of accuracy when compared to the diagnostic gold standard.
Measured: End of study
Secondary outcomes (1)
Proportion of Eosinophilic Esophagitis cases diagnosed in each cohort.
Determine the frequency of EoE among African individuals presenting with dysphagia in the U.S. and Mali. Allows for the comparison of diagnostic rates across different groups, providing insights into the prevalence.
Measured: End of study
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Jun 2025
- Study start28 Oct 2026 (estimated)
- Primary completion31 Aug 2027 (estimated)
- Study completion31 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for DysphagiaStudies of the same condition, open and under way.
- More trials run by National Institute of Allergy and Infectious Diseases (NIAID)The 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 N/A
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 70 participants (estimated)
Sponsor and investigators
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
- Investigators
- Gregory M Constantine, M.D., Principal investigator, National Institute of Allergy and Infectious Diseases (NIAID)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07027826
- Sponsor's protocol ID
- 10002313
- Other IDs
- 002313-I
- Status last verified
- 6 May 2026
- First submitted
- 18 Jun 2025
- Last updated
- 23 Oct 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No