<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT04479228</url>
  </required_header>
  <id_info>
    <org_study_id>WON_NAGIvsPlastic</org_study_id>
    <nct_id>NCT04479228</nct_id>
  </id_info>
  <brief_title>Plastic Stents vs. NAGI Bi-flanged Metal Stent for Endoscopic Ultrasound Guided Drainage of Walled-off Necrosis</brief_title>
  <official_title>A Randomized Control Trial of Plastic Stents vs. NAGI Bi-flanged Metal Stent for Endoscopic Ultrasound Guided Drainage of Walled-off Necrosis</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Asian Institute of Gastroenterology, India</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Asian Institute of Gastroenterology, India</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Introduction:&#xD;
&#xD;
      Walled off necrosis (WON) is defined as a well circumscribed pancreatic and/or peri&#xD;
      pancreatic necrosis containing a variable amount of necrotic tissue. WON usually occurs &gt;4&#xD;
      weeks after onset of necrotizing pancreatitis. It is associated with significant morbidity&#xD;
      and mortality especially if infected. Symptomatic WON should be drained either&#xD;
      percutaneously, endoscopically or surgically. Minimal invasive approaches are being&#xD;
      increasingly used for effective management of WON as it is associated with less adverse&#xD;
      events. Various recent studies have shown that endoscopic approach have improved clinical&#xD;
      outcome, less hospital stay and lower cost compared to surgical approach.&#xD;
&#xD;
      Endoscopic ultrasound guided drainage of WON with either plastic stents or lumen apposing&#xD;
      metal stents (LAMS) is mainstay of WON management. A systemic review based on retrospective&#xD;
      comparative studies showed no difference regarding treatment success for WON by plastic or&#xD;
      metal stents6. However, metal stent had shorter procedure time. A Single center RCT from USA&#xD;
      comparing LAMS vs multiple plastic stents for WON has shown that except shorter procedure&#xD;
      duration, there was no significant difference in treatment outcomes. To minimize LAMS related&#xD;
      adverse events, it should be removed within 3 weeks. However, in the same study 25.8%&#xD;
      patients of LAMS group and 55.2% patients of plastic stent group underwent additional&#xD;
      intervention within 72 hours for persistent symptoms.&#xD;
&#xD;
      Larger diameter, specific stent designs to reduce adverse events should have better outcome&#xD;
      with LAMS as compared to plastic stents. Primary outcome of this single center randomized&#xD;
      controlled trial is to examine whether dedicated NAGI bi-flanged metal stents (BFMS) are&#xD;
      superior to plastic stent in terms of short term and long term success.&#xD;
&#xD;
      Aims and Hypothesis:&#xD;
&#xD;
      The aim of the current study is to study whether NAGI BFMS are superior to plastic stent in&#xD;
      terms of short term and long term success in the EUS guided drainage of WON.&#xD;
&#xD;
      The investigators hypothesize that the clinical success with NAGI BFMS would be better than&#xD;
      plastic stents in the EUS guided drainage of WON.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      1.1 Patient recruitment Patients would be recruited from the in-patient or outpatient&#xD;
      department prior to their scheduled endoscopic intervention.&#xD;
&#xD;
      1.2 Study design This is a single center randomized controlled study with two parallel groups&#xD;
      without masking with a 1:1 allocation ratio&#xD;
&#xD;
      1.3. Study intervention - stent placement The procedures would be performed by experienced&#xD;
      endoscopists. All procedures will be performed with the patient in the left lateral position&#xD;
      under propofol sedation after administration of intravenous antibiotics (third generation&#xD;
      cephalosporins) A therapeutic linear echo-endoscope (UCT-180; Olympus Ltd, Tokyo, Japan) will&#xD;
      be used; the PFC assessed for size, wall maturity, thickness, interposing collaterals and&#xD;
      percentage of solid debris.&#xD;
&#xD;
      NAGI BFMS - The WON will be punctured using a standard 19-gauge FNA needle and the aspirate&#xD;
      was sent for biochemical and microbial analysis. A 0.025-inch (Visiglide; Olympus&#xD;
      Corporation, Tokyo, Japan) or 0.035-inch stiff guidewire (Jag Wire; Boston Scientific) passed&#xD;
      through the needle into the cyst cavity to form at least 1 to 2 loops under fluoroscopic&#xD;
      guidance. A 6F cystotome (Endo-flex GmbH Dusseldorf, Germany) will be passed over the&#xD;
      guidewire for creating a fistula. Subsequently, a 6-mm balloon dilator (Hurricane; Boston&#xD;
      Scientific Corporation or Titan balloon, Wilson Cook) will be used to further dilate the&#xD;
      fistula tract. After this, the stent delivery catheter is advanced over the guidewire across&#xD;
      the PFC wall and the BFMS (Nagi; Taewoong Medical, Gyeonggi-do, South Korea) deployed using&#xD;
      sonographic, fluoroscopic and endoscopic visualization.&#xD;
&#xD;
      Plastic stents - Double-pigtail plastic stents will be used. A minimum of one 10Fr pigtail&#xD;
      plastic stent will be placed. After initial EUS-guided access, the ostomy will be dilated&#xD;
      first, using a cystotome, and secondly with a balloon dilation. The plastic stent will be&#xD;
      inserted and delivered following the routine technique of each interventional endoscopist.&#xD;
      The number of the plastic stents and the size of the balloon used to dilate the ostomy will&#xD;
      depend on the WON size and content.&#xD;
&#xD;
      1.4 Stents NAGI bi-flanged metal stent (BFMS)- Nagi stent is a dedicated self-expandable&#xD;
      fully covered bi-flanged metal stent (BFMS) for drainage of pancreatic fluid collections. The&#xD;
      stent is short in length (20 or 30 mm) with caliber (10, 12, 14, or16 mm) having flared ends&#xD;
      (diameter 26 mm). Procedure-related adverse events will be managed accordingly and documented&#xD;
      Plastic stents - Two 7fr or 10 fr plastic stents will be used 1.5 Randomization The patients&#xD;
      would be randomised will be randomised to Plastic vs NAGI BFMS by using Med Cal C software&#xD;
      (version 12.3, Belgium). There will be no masking.&#xD;
&#xD;
      1.6 Post-procedural management After the drainage procedure, patients will be observed in the&#xD;
      hospital for symptomatic improvement or development of any adverse events. Oral liquids are&#xD;
      allowed 6 hours after the procedure. Intravenous antibiotics will be continued for 2 to 3&#xD;
      days which will be later changed to the oral route.&#xD;
&#xD;
      All patients will be re-assessed within 72 hours after EUS guided drainage for symptomatic&#xD;
      relief. In case of persistent symptoms, the most beneficial therapeutic approach for the&#xD;
      patient will be adopted as per expert multimodality team of endoscopists, surgeon and&#xD;
      interventional radiologist such as placement of nasocystic drain, coaxial plastic stent&#xD;
      placement in BFMS, endoscopic necrosectomy or percutaneous drainage.&#xD;
&#xD;
      In case of symptomatic relief and significant reduction in size of WON, patient will be&#xD;
      followed up after 1 week and at 4 week or early if symptoms recur and/or any new symptom&#xD;
      appears. In case of complete symptomatic relief and disappearance of WON at 4 weeks, metal&#xD;
      stent will be removed.&#xD;
&#xD;
      If persistent collection or there is evidence of DPDS, then in patients with initial plastic&#xD;
      stent placement, stent will not be removed. In BFMS group, BFMS will be replaced by plastic&#xD;
      stent. Patient will be observed in hospital for 24 hours 1.7 Outcome measurements The primary&#xD;
      outcome measurement is Clinical success at 4 weeks determined by the reduction of the&#xD;
      collection (&lt;50% or &lt;5 cm in size) along with resolution of symptoms Secondary outcomes&#xD;
      include&#xD;
&#xD;
        1. Re-interventions&#xD;
&#xD;
        2. Long term clinical success at 24 weeks&#xD;
&#xD;
        3. Adverse events&#xD;
&#xD;
        4. Cost - effectiveness&#xD;
&#xD;
      Technical success: It is defined as the correct deployment of stent at both ends with&#xD;
      visualization of drainage of the liquid.&#xD;
&#xD;
      Clinical success: It is defined as resolution of symptoms and significant reduction in of&#xD;
      collection size (&lt; 50% or &lt;5 cm in size).&#xD;
&#xD;
      Recurrence: It is appearance of symptomatic fluid collection evident on imaging during&#xD;
      follow-up after documented clinical success.&#xD;
&#xD;
      Adverse events: It is defined as undesirable situations during the study period whether&#xD;
      related or unrelated to the EUS guided drainage.&#xD;
&#xD;
      1.8 Follow-up Patient will be assessed on day 1 to 3, then at 1, 4, 8 weeks followed by 12&#xD;
      and 24 weeks by personnel participating in the study. At each visit, information regarding&#xD;
      signs and symptoms, adverse events and recurrence will be collected. In case of mortality&#xD;
      during study period, any possible relation to endoscopic procedure will be investigated and&#xD;
      will be noted.&#xD;
&#xD;
      1.9 Sample size calculation The success rate of metal stent is assumed as 75 % and 45% for&#xD;
      plastic stent. The required sample size with 80% power and 0.05 as type 1 error is 40 per&#xD;
      group&#xD;
&#xD;
      Statistical Formula for estimation of sample size :&#xD;
&#xD;
      n= 2 (Zα +Zβ)2 (P1+Q1+P2+Q2)/ (P1 -P2 ) X(P1-P2)&#xD;
&#xD;
      where, n = Sample size&#xD;
&#xD;
      P1 proportion of outcome measure under Group1 (Success rate of metal stent and assumed to be&#xD;
      75 %) Q1 proportion of failure rate metal stent (1 - 0.85 ) P2 proportion of success rate in&#xD;
      plastic group2 (success rate and assumed as 45 %) Q2 proportion failure rate of plastic stent&#xD;
      in group 2 (1 - 0.45) zα is factor corresponding to type 1 error with two sided test and is&#xD;
      taken as 1.96 Zβ factor corresponding to type 11 error i.e (1- β) is power of and is usually&#xD;
      taken as 80 % and the value =0.84 Forty patients will be recruited in each group to reject&#xD;
      the null hypothesis that the proportion of clinical success in the LAMS group is equal to&#xD;
      that of the plastic stent group with an 80% power with 5% type 1 error. A planned interim&#xD;
      analysis will be done at half of the recruitment.&#xD;
&#xD;
      1.10 Statistical analyses The continuous variables will be described as mean, standard&#xD;
      deviation, median, range and interquartile range. Categorical variables will be described as&#xD;
      percentages of different categories.&#xD;
&#xD;
      Primary outcome will be tested with chi-square test or Fisher's exact test. The level of&#xD;
      significance has been set at 5%. To quantify the magnitude of the difference the relative&#xD;
      risk and odds ratio will be calculated with 95% confidence interval. Univariate and&#xD;
      multivariate analysis will be done to determine which are the factors associated with&#xD;
      clinical success and clinical recurrence. Kaplan-Meier survival analysis will be done for&#xD;
      appearance clinical recurrence.&#xD;
&#xD;
      1.11 Withdrawal of individual subjects Subjects can leave the study at any time for any&#xD;
      reason if they wish to do so without any consequences. The treating physician can decide to&#xD;
      withdraw a subject from the study for any medical reason. In case of withdrawal, the reason&#xD;
      for withdrawal and, if applicable, the alternative treatment, would be recorded.&#xD;
&#xD;
      1.12 Participating centres Asian Institute of Gastroenterology - Hyderabad&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Not yet recruiting</last_known_status>
  <start_date type="Anticipated">August 1, 2020</start_date>
  <completion_date type="Anticipated">January 1, 2022</completion_date>
  <primary_completion_date type="Anticipated">August 1, 2021</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Parallel Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Number of patient achieving Clinical Success</measure>
    <time_frame>4 weeks</time_frame>
    <description>Clinical success at 4 weeks determined by the reduction of the collection (&lt;50% or &lt;5 cm in size) along with resolution of symptoms.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Re-Interventions</measure>
    <time_frame>4 weeks</time_frame>
    <description>The number of re-interventions required to achieve primary outcome, which includes need for necrosectomy, nano-cystic drainage placement, placement for nasogastric or nasojejunal tube for feeding, need for percutaneous or surgical drainage.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Number of patients achieving Long term success</measure>
    <time_frame>24 weeks</time_frame>
    <description>Long term success defined as absence of persistent collection or recurrence at 24 weeks.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Number of patients developing Adverse events</measure>
    <time_frame>24 weeks</time_frame>
    <description>It is defined as undesirable situations during the study period whether related or unrelated to the EUS guided drainage.</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Anticipated">80</enrollment>
  <condition>Acute Necrotizing Pancreatitis</condition>
  <condition>Walled Off Necrosis</condition>
  <arm_group>
    <arm_group_label>NAGI bi-flanged metal stent (BFMS)</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>The WON will be punctured using a standard 19-gauge FNA needle and the aspirate was sent for biochemical and microbial analysis. A 0.025-inch (Visiglide; Olympus Corporation, Tokyo, Japan) or 0.035-inch stiff guidewire (Jag Wire; Boston Scientific) passed through the needle into the cyst cavity to form at least 1 to 2 loops under fluoroscopic guidance. A 6F cystotome (Endo-flex GmbH Dusseldorf, Germany) will be passed over the guidewire for creating a fistula. Subsequently, a 6-mm balloon dilator (Hurricane; Boston Scientific Corporation or Titan balloon, Wilson Cook) will be used to further dilate the fistula tract. After this, the stent delivery catheter is advanced over the guidewire across the PFC wall and the BFMS (Nagi; Taewoong Medical, Gyeonggi-do, South Korea) deployed using sonographic, fluoroscopic and endoscopic visualization.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Plastic stents</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Double-pigtail plastic stents will be used. A minimum of one 10Fr pigtail plastic stent will be placed. After initial EUS-guided access, the ostomy will be dilated first, using a cystotome, and secondly with a balloon dilation. The plastic stent will be inserted and delivered following the routine technique of each interventional endoscopist. The number of the plastic stents and the size of the balloon used to dilate the ostomy will depend on the WON size and content.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Endosonography guided transmural drainage</intervention_name>
    <description>The procedures would be performed by experienced endoscopists. All procedures will be performed with the patient in the left lateral position under propofol sedation after administration of intravenous antibiotics (third generation cephalosporins) A therapeutic linear echo-endoscope (UCT-180; Olympus Ltd, Tokyo, Japan) will be used; the PFC assessed for size, wall maturity, thickness, interposing collaterals and percentage of solid debris</description>
    <arm_group_label>NAGI bi-flanged metal stent (BFMS)</arm_group_label>
    <arm_group_label>Plastic stents</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Adult &gt;18 years,&#xD;
&#xD;
          -  Patient with symptomatic WON&#xD;
&#xD;
          -  Debris &lt;50% (based on cross sectional imaging)&#xD;
&#xD;
          -  Written informed consent&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Pregnancy or breast feeding,&#xD;
&#xD;
          -  Severe coagulopathy INR &gt;1.5 which is not correctable and/or platelets &lt;50000/mm3&#xD;
&#xD;
          -  Endoscopic drainage is technically not feasible&#xD;
&#xD;
          -  Fluid collections other than WON&#xD;
&#xD;
          -  Patient who is unable to understand study protocol or not willing for follow-up&#xD;
             requirements&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <overall_contact>
    <last_name>Nitin Jagtap, MD</last_name>
    <phone>04023378888</phone>
    <email>docnits13@gmail.com</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Krithikrishna Koduri, MD</last_name>
    <phone>04023378888</phone>
    <email>krithivk@gmail.com</email>
  </overall_contact_backup>
  <verification_date>July 2020</verification_date>
  <study_first_submitted>July 15, 2020</study_first_submitted>
  <study_first_submitted_qc>July 19, 2020</study_first_submitted_qc>
  <study_first_posted type="Actual">July 21, 2020</study_first_posted>
  <last_update_submitted>July 19, 2020</last_update_submitted>
  <last_update_submitted_qc>July 19, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">July 21, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Pancreatitis</mesh_term>
    <mesh_term>Pancreatitis, Acute Necrotizing</mesh_term>
    <mesh_term>Necrosis</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
    <ipd_description>Data sharing won't be allowed to outside researcher.</ipd_description>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT04479228
org study id: WON_NAGIvsPlastic
nct id: NCT04479228
lead sponsor: 
has dmc: Yes
is fda regulated drug: No
is fda regulated device: No
Introduction:

      Walled off necrosis (WON) is defined as a well circumscribed pancreatic and/or peri
      pancreatic necrosis containing a variable amount of necrotic tissue. WON usually occurs >4
      weeks after onset of necrotizing pancreatitis. It is associated with significant morbidity
      and mortality especially if infected. Symptomatic WON should be drained either
      percutaneously, endoscopically or surgically. Minimal invasive approaches are being
      increasingly used for effective management of WON as it is associated with less adverse
      events. Various recent studies have shown that endoscopic approach have improved clinical
      outcome, less hospital stay and lower cost compared to surgical approach.

      Endoscopic ultrasound guided drainage of WON with either plastic stents or lumen apposing
      metal stents (LAMS) is mainstay of WON management. A systemic review based on retrospective
      comparative studies showed no difference regarding treatment success for WON by plastic or
      metal stents6. However, metal stent had shorter procedure time. A Single center RCT from USA
      comparing LAMS vs multiple plastic stents for WON has shown that except shorter procedure
      duration, there was no significant difference in treatment outcomes. To minimize LAMS related
      adverse events, it should be removed within 3 weeks. However, in the same study 25.8%
      patients of LAMS group and 55.2% patients of plastic stent group underwent additional
      intervention within 72 hours for persistent symptoms.

      Larger diameter, specific stent designs to reduce adverse events should have better outcome
      with LAMS as compared to plastic stents. Primary outcome of this single center randomized
      controlled trial is to examine whether dedicated NAGI bi-flanged metal stents (BFMS) are
      superior to plastic stent in terms of short term and long term success.

      Aims and Hypothesis:

      The aim of the current study is to study whether NAGI BFMS are superior to plastic stent in
      terms of short term and long term success in the EUS guided drainage of WON.

      The investigators hypothesize that the clinical success with NAGI BFMS would be better than
      plastic stents in the EUS guided drainage of WON.
1.1 Patient recruitment Patients would be recruited from the in-patient or outpatient
      department prior to their scheduled endoscopic intervention.

      1.2 Study design This is a single center randomized controlled study with two parallel groups
      without masking with a 1:1 allocation ratio

      1.3. Study intervention - stent placement The procedures would be performed by experienced
      endoscopists. All procedures will be performed with the patient in the left lateral position
      under propofol sedation after administration of intravenous antibiotics (third generation
      cephalosporins) A therapeutic linear echo-endoscope (UCT-180; Olympus Ltd, Tokyo, Japan) will
      be used; the PFC assessed for size, wall maturity, thickness, interposing collaterals and
      percentage of solid debris.

      NAGI BFMS - The WON will be punctured using a standard 19-gauge FNA needle and the aspirate
      was sent for biochemical and microbial analysis. A 0.025-inch (Visiglide; Olympus
      Corporation, Tokyo, Japan) or 0.035-inch stiff guidewire (Jag Wire; Boston Scientific) passed
      through the needle into the cyst cavity to form at least 1 to 2 loops under fluoroscopic
      guidance. A 6F cystotome (Endo-flex GmbH Dusseldorf, Germany) will be passed over the
      guidewire for creating a fistula. Subsequently, a 6-mm balloon dilator (Hurricane; Boston
      Scientific Corporation or Titan balloon, Wilson Cook) will be used to further dilate the
      fistula tract. After this, the stent delivery catheter is advanced over the guidewire across
      the PFC wall and the BFMS (Nagi; Taewoong Medical, Gyeonggi-do, South Korea) deployed using
      sonographic, fluoroscopic and endoscopic visualization.

      Plastic stents - Double-pigtail plastic stents will be used. A minimum of one 10Fr pigtail
      plastic stent will be placed. After initial EUS-guided access, the ostomy will be dilated
      first, using a cystotome, and secondly with a balloon dilation. The plastic stent will be
      inserted and delivered following the routine technique of each interventional endoscopist.
      The number of the plastic stents and the size of the balloon used to dilate the ostomy will
      depend on the WON size and content.

      1.4 Stents NAGI bi-flanged metal stent (BFMS)- Nagi stent is a dedicated self-expandable
      fully covered bi-flanged metal stent (BFMS) for drainage of pancreatic fluid collections. The
      stent is short in length (20 or 30 mm) with caliber (10, 12, 14, or16 mm) having flared ends
      (diameter 26 mm). Procedure-related adverse events will be managed accordingly and documented
      Plastic stents - Two 7fr or 10 fr plastic stents will be used 1.5 Randomization The patients
      would be randomised will be randomised to Plastic vs NAGI BFMS by using Med Cal C software
      (version 12.3, Belgium). There will be no masking.

      1.6 Post-procedural management After the drainage procedure, patients will be observed in the
      hospital for symptomatic improvement or development of any adverse events. Oral liquids are
      allowed 6 hours after the procedure. Intravenous antibiotics will be continued for 2 to 3
      days which will be later changed to the oral route.

      All patients will be re-assessed within 72 hours after EUS guided drainage for symptomatic
      relief. In case of persistent symptoms, the most beneficial therapeutic approach for the
      patient will be adopted as per expert multimodality team of endoscopists, surgeon and
      interventional radiologist such as placement of nasocystic drain, coaxial plastic stent
      placement in BFMS, endoscopic necrosectomy or percutaneous drainage.

      In case of symptomatic relief and significant reduction in size of WON, patient will be
      followed up after 1 week and at 4 week or early if symptoms recur and/or any new symptom
      appears. In case of complete symptomatic relief and disappearance of WON at 4 weeks, metal
      stent will be removed.

      If persistent collection or there is evidence of DPDS, then in patients with initial plastic
      stent placement, stent will not be removed. In BFMS group, BFMS will be replaced by plastic
      stent. Patient will be observed in hospital for 24 hours 1.7 Outcome measurements The primary
      outcome measurement is Clinical success at 4 weeks determined by the reduction of the
      collection (<50% or <5 cm in size) along with resolution of symptoms Secondary outcomes
      include

        1. Re-interventions

        2. Long term clinical success at 24 weeks

        3. Adverse events

        4. Cost - effectiveness

      Technical success: It is defined as the correct deployment of stent at both ends with
      visualization of drainage of the liquid.

      Clinical success: It is defined as resolution of symptoms and significant reduction in of
      collection size (< 50% or <5 cm in size).

      Recurrence: It is appearance of symptomatic fluid collection evident on imaging during
      follow-up after documented clinical success.

      Adverse events: It is defined as undesirable situations during the study period whether
      related or unrelated to the EUS guided drainage.

      1.8 Follow-up Patient will be assessed on day 1 to 3, then at 1, 4, 8 weeks followed by 12
      and 24 weeks by personnel participating in the study. At each visit, information regarding
      signs and symptoms, adverse events and recurrence will be collected. In case of mortality
      during study period, any possible relation to endoscopic procedure will be investigated and
      will be noted.

      1.9 Sample size calculation The success rate of metal stent is assumed as 75 % and 45% for
      plastic stent. The required sample size with 80% power and 0.05 as type 1 error is 40 per
      group

      Statistical Formula for estimation of sample size :

      n= 2 (Zα +Zβ)2 (P1+Q1+P2+Q2)/ (P1 -P2 ) X(P1-P2)

      where, n = Sample size

      P1 proportion of outcome measure under Group1 (Success rate of metal stent and assumed to be
      75 %) Q1 proportion of failure rate metal stent (1 - 0.85 ) P2 proportion of success rate in
      plastic group2 (success rate and assumed as 45 %) Q2 proportion failure rate of plastic stent
      in group 2 (1 - 0.45) zα is factor corresponding to type 1 error with two sided test and is
      taken as 1.96 Zβ factor corresponding to type 11 error i.e (1- β) is power of and is usually
      taken as 80 % and the value =0.84 Forty patients will be recruited in each group to reject
      the null hypothesis that the proportion of clinical success in the LAMS group is equal to
      that of the plastic stent group with an 80% power with 5% type 1 error. A planned interim
      analysis will be done at half of the recruitment.

      1.10 Statistical analyses The continuous variables will be described as mean, standard
      deviation, median, range and interquartile range. Categorical variables will be described as
      percentages of different categories.

      Primary outcome will be tested with chi-square test or Fisher's exact test. The level of
      significance has been set at 5%. To quantify the magnitude of the difference the relative
      risk and odds ratio will be calculated with 95% confidence interval. Univariate and
      multivariate analysis will be done to determine which are the factors associated with
      clinical success and clinical recurrence. Kaplan-Meier survival analysis will be done for
      appearance clinical recurrence.

      1.11 Withdrawal of individual subjects Subjects can leave the study at any time for any
      reason if they wish to do so without any consequences. The treating physician can decide to
      withdraw a subject from the study for any medical reason. In case of withdrawal, the reason
      for withdrawal and, if applicable, the alternative treatment, would be recorded.

      1.12 Participating centres Asian Institute of Gastroenterology - Hyderabad
allocation: Randomized
intervention model: Parallel Assignment
primary purpose: Treatment
masking: None (Open Label)
measure: Number of patient achieving Clinical Success
time frame: 4 weeks
description: Clinical success at 4 weeks determined by the reduction of the collection (<50% or <5 cm in size) along with resolution of symptoms.
measure: Re-Interventions
time frame: 4 weeks
description: The number of re-interventions required to achieve primary outcome, which includes need for necrosectomy, nano-cystic drainage placement, placement for nasogastric or nasojejunal tube for feeding, need for percutaneous or surgical drainage.
measure: Number of patients achieving Long term success
time frame: 24 weeks
description: Long term success defined as absence of persistent collection or recurrence at 24 weeks.
measure: Number of patients developing Adverse events
time frame: 24 weeks
description: It is defined as undesirable situations during the study period whether related or unrelated to the EUS guided drainage.
arm group label: NAGI bi-flanged metal stent (BFMS)
arm group type: Experimental
description: The WON will be punctured using a standard 19-gauge FNA needle and the aspirate was sent for biochemical and microbial analysis. A 0.025-inch (Visiglide; Olympus Corporation, Tokyo, Japan) or 0.035-inch stiff guidewire (Jag Wire; Boston Scientific) passed through the needle into the cyst cavity to form at least 1 to 2 loops under fluoroscopic guidance. A 6F cystotome (Endo-flex GmbH Dusseldorf, Germany) will be passed over the guidewire for creating a fistula. Subsequently, a 6-mm balloon dilator (Hurricane; Boston Scientific Corporation or Titan balloon, Wilson Cook) will be used to further dilate the fistula tract. After this, the stent delivery catheter is advanced over the guidewire across the PFC wall and the BFMS (Nagi; Taewoong Medical, Gyeonggi-do, South Korea) deployed using sonographic, fluoroscopic and endoscopic visualization.
arm group label: Plastic stents
arm group type: Experimental
description: Double-pigtail plastic stents will be used. A minimum of one 10Fr pigtail plastic stent will be placed. After initial EUS-guided access, the ostomy will be dilated first, using a cystotome, and secondly with a balloon dilation. The plastic stent will be inserted and delivered following the routine technique of each interventional endoscopist. The number of the plastic stents and the size of the balloon used to dilate the ostomy will depend on the WON size and content.
intervention type: Device
intervention name: Endosonography guided transmural drainage
description: The procedures would be performed by experienced endoscopists. All procedures will be performed with the patient in the left lateral position under propofol sedation after administration of intravenous antibiotics (third generation cephalosporins) A therapeutic linear echo-endoscope (UCT-180; Olympus Ltd, Tokyo, Japan) will be used; the PFC assessed for size, wall maturity, thickness, interposing collaterals and percentage of solid debris
arm group label: NAGI bi-flanged metal stent (BFMS)
arm group label: Plastic stents
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: No
last name: Nitin Jagtap, MD
phone: 04023378888
email: docnits13@gmail.com
last name: Krithikrishna Koduri, MD
phone: 04023378888
email: krithivk@gmail.com
responsible party type: Sponsor
mesh term: Pancreatitis
mesh term: Pancreatitis, Acute Necrotizing
mesh term: Necrosis
sharing ipd: No
ipd description: Data sharing won't be allowed to outside researcher.