An interventional study of Esophageal string test in Dysphagia and Eosinophilic Esophagitis, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Recruiting at 3 sites in 2 countries. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Not applicable, Interventional, and Diagnostic
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.
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.
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):
Secondary Endpoints:
-Proportion of EoE cases diagnosed in each cohort.
871 studies on the registry are indexed under Deglutition Disorders; 237 are open to participants now.
This study's planned enrollment of 70 is above the median of 60 across 578 interventional studies indexed under Deglutition Disorders.
Browse Deglutition Disorders studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.
Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
In order to be eligible to participate in this study, an individual must meet all of the following criteria:
EXCLUSION CRITERIA:
An individual who meets any of the following criteria will be excluded from participation in this study:
3a. mepolizumab (Nucala)
3b. reslizumab (Cinqair, Cinqaero)
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 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.
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The esophageal string test is a minimally invasive procedure used to collect esophageal secretions for diagnostic analysis.
Device: Esophageal string test
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.
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.
Time frame: End of study
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.
Time frame: End of study
Plan to share: No
Start is estimated for Nov 2026; primary completion for Aug 2027, 9 months later.
Of 288 non-industry interventional studies with no phase under Deglutition Disorders, half reached primary completion within 21 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 39. This study's planned 9 months is below that.
Counting every sponsor, half of 297 studies reached it within 21 months; a quarter within 10 and three quarters within 38.
Start moved 32 times since we started tracking on Sep 25, 2026: Sep 2026 → Nov 2026, last on Nov 10, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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