Comparing immediate necrosectomy to a step-up approach for treating walled-off necrosis

Immediate Necrosectomy vs. Step-up Approach After EUS-guided Drainage of Walled-off Necrosis: a Multicenter Randomized Controlled Trial (WONDER-01)

Not applicable Interventional Tokyo University · NCT05451901

This study is testing whether a quick procedure to remove walled-off necrosis can help people with symptoms from acute pancreatitis recover faster than the usual step-by-step treatment.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment70 (estimated)
Ages18 Years and up
SexAll
SponsorTokyo University Academic / other
Locations21 sites (Bunkyō-Ku, Tokyo and 20 other locations)
Trial IDNCT05451901 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effectiveness of immediate endoscopic necrosectomy (EN) following endoscopic ultrasonography (EUS)-guided drainage versus a step-up approach for managing symptomatic walled-off necrosis (WON) resulting from acute pancreatitis. The study aims to determine if immediate EN can reduce treatment duration without increasing adverse events compared to the traditional step-up method. Patients with WON that is 4 cm or larger and showing signs of infection or gastrointestinal symptoms will be enrolled. The trial will assess the time to clinical success between the two treatment strategies.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older with symptomatic walled-off necrosis that is 4 cm or larger.

Not a fit: Patients with walled-off necrosis that cannot be accessed via EUS-guided drainage or those with severe coagulopathy may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could lead to faster recovery times and improved outcomes for patients with infected walled-off necrosis.

How similar studies have performed: Recent evidence suggests that immediate endoscopic necrosectomy may be a safe and effective approach, indicating potential success for this trial.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients with WON defined according to the revised Atlanta classification
* The longest diameter of WON is 4 cm or larger
* Patients with at least one out of the following conditions; signs of infection, gastrointestinal symptoms, abdominal symptoms, obstructive jaundice
* Patients who need drainage for WON
* Age of 18 years or older
* Patients or their representatives provide informed consent
* Patients who visit or are hospitalized at the participating institutions

Exclusion Criteria:

* WON inaccessible by EUS-guided approach
* AXIOS stent has already been placed into the WON prior to the enrollment
* Severe coagulopathy; Platelet count \< 50,000/mm3 or prothrombin time international normalized ratio (PT-INR) \>1.5
* Patients on antithrombotic agents which cannot be managed according to the "guideline for gastroenterological endoscopy in patients undergoing antithrombotic treatment (Dig Endosc. 2014 Jan;26(1):1-14.)"
* Patients who cannot tolerate endoscopic procedures
* Pregnant women
* Patients considered inappropriate for inclusion by investigators

Where this trial is running

Bunkyō-Ku, Tokyo and 20 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Pancreatic Fluid CollectionWalled-off NecrosisPancreatitis, Acute NecrotizingPancreatic PseudocystEndosonographyDrainageStentsEndoscopic necrosectomy
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.