UMIN-ICDS Clinical Trial

Public title

A prospective study on the usefulness of the Temporary Narrowing Test for predicting the therapeutic efficacy of endoscopic antireflux mucosal resection

Acronym

TNT-ER Study (Temporary Narrowing Test - Endoscopic Reflux Study)

Scientific Title

A prospective study on the usefulness of the Temporary Narrowing Test for predicting the therapeutic efficacy of endoscopic antireflux mucosal resection

Scientific Title:Acronym

TNT-ER Study (Temporary Narrowing Test - Endoscopic Reflux Study)

Region

Japan

Condition

Gastroesophageal Reflux Disease : GERD

Classification by specialty

Medicine in general

Gastroenterology

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

This study aims to evaluate the usefulness of the Temporary Narrowing Test in predicting the therapeutic efficacy of endoscopic antireflux mucosal resection by simulating the procedure using the Temporary Narrowing Test prior to endoscopic antireflux mucosal resection in patients with GERD.

Basic objectives2

Efficacy

Basic objectives -Others

Trial characteristics_1

Trial characteristics_2

Developmental phase

Primary outcomes

Correlation between changes in symptom scores (GERD-HRQL, GerdQ, and FSSG) from baseline at 3 days after the Temporary Narrowing Test and at 8 weeks after endoscopic antireflux mucosal resection.

Key secondary outcomes

1. Procedure time and technical success rate of the Temporary Narrowing Test
The Temporary Narrowing Test (TNT) is an endoscopic procedure in which the mucosa of the gastric cardia is approximated using endoscopic clips. This outcome was evaluated to assess the feasibility and potential standardization of the procedure.
Procedure time was defined as the interval from insertion of the first endoscopic clip into the endoscope to completion of mucosal plication at the gastric cardia.
Technical success was defined as successful narrowing of the gastric cardia achieved by approximating the anterior and posterior walls using endoscopic clips.
The technical success rate was defined as the proportion of technically successful cases among all enrolled patients.

2. Incidence of TNT related adverse events
TNT related adverse events were defined as newly developed or worsened symptoms after TNT for which an association with TNT could not be excluded and were assessed to evaluate procedural safety.
Bleeding was defined as bleeding from the TNT site requiring endoscopic hemostasis blood transfusion or other intervention or a decrease in hemoglobin level of 2.0 g per dL or more from baseline.
Mucosal laceration was defined as a TNT related mucosal tear measuring 10 mm or more in length.
Passage disturbance was defined as subjective symptoms such as dysphagia or a sensation of food impaction.

3. TNT maintenance rate and clip retention rate
Although clips placed during TNT are expected to detach spontaneously they may remain at the time of endoscopic antireflux mucosal resection and require removal therefore these outcomes were evaluated.
TNT maintenance was defined as retention of all placed clips with preserved mucosal narrowing.
Clip retention was defined as the presence of one or more remaining clips.
Both rates were calculated as proportions among all enrolled patients.

Study type

Interventional

Basic design

Single arm

Randomization

Non-randomized

Randomization unit

Blinding

Open -no one is blinded

Control

Uncontrolled

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

1

Purpose of intervention

Diagnosis

Type of intervention

Maneuver

Interventions/Control_1

Acid-suppressive medications are discontinued for 14 days prior to the Temporary Narrowing Test (TNT), after which self-administered symptom questionnaires are obtained.
During TNT, narrowing of the gastric cardia is achieved by approximating and fixing the mucosal folds of the anterior and posterior walls immediately below the gastric cardia (gastroesophageal flap valve). The detailed procedure is as follows:

A nylon thread approximately 2 m in length is tied and fixed to an endoscopic clip to create a thread-attached clip.

The thread-attached clip is passed through the endoscope working channel, deployed in the stomach, and fixed to the mucosal fold of the anterior wall immediately below the gastric cardia. The opposite end of the nylon thread remains outside the patient through the working channel.

The externalized nylon thread is passed through the jaws of another clip, which is then delivered into the stomach through the working channel, deployed, and fixed to the mucosal fold of the posterior wall immediately below the gastric cardia. By pulling the nylon thread from outside the patient, the clip fixed to the anterior wall mucosal fold is drawn toward the posterior wall.

For reinforcement, an additional clip is deployed to grasp and fix both the anterior and posterior mucosal folds approximated in step (3).

Finally, the nylon thread is cut and retrieved, and the procedure is completed.

With acid-suppressive medications discontinued, self-administered symptom questionnaires are obtained 3 days after TNT.
In addition, 8 weeks after endoscopic antireflux mucosal resection, acid-suppressive medications are again discontinued for 14 days, followed by 24-hour pH monitoring, esophageal manometry, and upper gastrointestinal endoscopy, after which self-administered symptom questionnaires are obtained.

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

130

years-old

>

Gender

Male and Female

Key inclusion criteria

Individuals aged 18 years or older at the time of obtaining informed consent.
Individuals with symptoms of GERD, including typical symptoms such as heartburn and acid regurgitation, as well as atypical symptoms such as chest pain, chronic cough, and laryngitis.
Individuals who desire and are scheduled to undergo endoscopic antireflux mucosal resection, including those with a history of prior treatments.
Individuals who are able to provide written informed consent to participate in this study.

Key exclusion criteria

Individuals who are unable to undergo pre treatment evaluations, including upper gastrointestinal endoscopy, esophageal manometry, and 24 hour pH impedance monitoring.
Individuals for whom completion of self administered symptom questionnaires is difficult.
Individuals who are unable to discontinue acid suppressive medications, including proton pump inhibitors, potassium competitive acid blockers, and H2 receptor antagonists.
Individuals who are pregnant or may be pregnant.
Individuals deemed inappropriate for participation in this study by the principal investigator or co investigators.

Target sample size

15

Name of lead principal investigator

1st name	Shiro
Middle name
Last name	Oka

Organization

Hiroshima University

Division name

Department of Gastroenterology, Graduate School of Biomedical and Health Sciences

Zip code

734-8551

Address

Department of Gastroenterology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan

TEL

082-257-5193

Email

oka4683@hiroshima-u.ac.jp

Name of contact person

1st name	Hidenori
Middle name
Last name	Tanaka

Organization

Hiroshima University Hospital, Hiroshima, Japan

Division name

Endoscopy Center

Zip code

734-8551

Address

1-2-3 Kasumi, Minami-ku, Hiroshima

TEL

0822575555

Homepage URL

Email

hitanaka@hiroshima-u.ac.jp

Institute

Hiroshima University

Institute

Department

Personal name

YUKI AMIOKA

Organization

Hiroshima University

Organization

Division

Category of Funding Organization

Other

Nationality of Funding Organization

Japan

Co-sponsor

Name of secondary funder(s)

Organization

Ethical Committee for Clinical Research of Hiroshima University

Address

Kasumi 1-2-3 Minami-Ku, Hiroshima

Tel

082-257-1947

Email

iryo-sinsa@office.hiroshima-u.ac.jp

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

Date of disclosure of the study information

2026

Year

03

Month

18

Day

URL releasing protocol

Publication of results

Unpublished

URL related to results and publications

Number of participants that the trial has enrolled

Results

Results date posted

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Participant flow

Adverse events

Outcome measures

Plan to share IPD

IPD sharing Plan description

Recruitment status

Open public recruiting

Date of protocol fixation

2026

Year

03

Month

18

Day

Date of IRB

2026

Year

03

Month

18

Day

Anticipated trial start date

2026

Year

03

Month

18

Day

Last follow-up date

2028

Year

03

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

2030

Year

11

Month

30

Day

Other related information

Registered date

2026

Year

03

Month

18

Day

Last modified on

2026

Year

03

Month

18

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/icdr_e/ctr_view.cgi?recptno=R000069049