Alfapump® System in the Treatment of Refractory or Recurrent Ascites (POSEIDON Study)

NCT03973866 | Unknown DMC FDA Device

• 1 other identifier: 2017-AAR-010
• Study Type: interventional
• Target: 110
• Locations: 2 countries
• Sites: 15

Brief Summary

The POSEIDON study is a multi-center, prospective, single arm, crossover pivotal study enrolling up to 70 pivotal cohort patients and up to 45 additional Roll-in patients with refractory or recurrent ascites at up to 20 sites. Pivotal cohort patients will undergo a 3-month pre-implant observation phase after enrollment, followed by implantation of the alfapump and 24 months of post-implant follow up. An analysis will be conducted to support an application for device approval when a minimum of 40 treated pivotal cohort patients are through 6 months.

Conditions

Ascites

Outcome Measures

Primary Outcomes (3)

• Per-patient ratio of post-implant to pre-implant with respect to average monthly number of therapeutic paracentesis

  Defined as removal of ascites ≥1.5L through needle puncture of abdominal wall

  Comparing data from the post-implant 3-month observation period to data from the pre-implant 3-month observation period:

• Proportion of patients with at least 50% reduction in number of therapeutic paracenteses from the pre-observation period to post-observation period

  Defined as removal of ascites ≥1.5L through needle puncture of abdominal wall

  Comparing data from the post-implant 3-month observation period to data from the pre-implant 3-month observation period

• Combined rate of open surgical reintervention due to pump system related adverse event or to restore pump functionality, pump explant due to pump system related adverse event, or pump system related death

  Safety of the alfapump implant procedure and alfapump therapy as determined by rates of explant, reintervention, and other serious device or procedure related adverse events

  from time of pump implant through 6 months post-implant

Secondary Outcomes (4)

• Requirement for large volume paracentesis (LVP): change in the average number of LVP events per month (that consist of removing ≥ 5L of ascitic fluid)

  in the post-implant 3-month primary endpoint observation period compared to the pre-implant observation period

• Change of cumulative volume of ascitic fluid removed by means of therapeutic paracentesis

  in the post-implant 3-month primary endpoint observation period as compared to the pre-implant 3-month observation period

• Change in SF-36 Physical Component Score

  post-implant 3-month primary endpoint observation period as compared to the pre-implant 3-month observation period

• Change in Ascites-Q Score

  in the post-implant 3-month primary endpoint observation period as compared to the pre-implant 3-month observation period

Study Arms (1)

Alfapump

EXPERIMENTAL

Implantation of Alfapump

Device: Alfapump

Interventions

Alfapump DEVICE

Implantation of alfapump

Alfapump

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• At the time of Initial Screening:
• Patients \> 18 years of age
• Cirrhosis of the liver defined by histological and/or clinical, endoscopic, laboratory and radiological criteria.
• Refractory or recurrent ascites primarily managed with periodic therapeutic paracentesis . Patients must have a minimum of 2 therapeutic paracenteses in the 30 Days prior to enrollment
• Not a candidate for (e.g. refused, contraindicated) Transjugular intrahepatic portosystemic shunt (TIPS) or previously implanted TIPS is permanently obstructed or non-functioning.
• Screened for esophageal varices and on optimal management
• Absence of contraindications to prophylactic antibiotic use from time of pump implant
• Life expectancy of at least 6 months following pump implant (approximately 10 months from enrollment)
• Capable of giving written informed consent, willing to comply with study procedures including the 3-month pre-implant observation period and ability to operate and charge the device.
• Women of childbearing age should use adequate contraceptives.
• Reassessed at time of implant procedure (Pivotal Cohort Only):
• Has required a minimum of 5 therapeutic paracenteses in the 3-month observation period prior to pump implant

You may not qualify if:

• At the time of Initial Screening:
• Renal failure defined as serum creatinine higher than 1.5 mg/dL
• More than one episode of spontaneous bacterial peritonitis over the previous 6 months
• More than one episode of bacterascites over the previous 6 months
• Recurrent urinary infections as per standard criteria, defined as 2 or more episodes over the last 6 months
• Evidence of loculated ascites, as per imaging
• Hepatocellular carcinoma, exceeding Milan criteria or for which RF ablation is anticipated
• Pregnant females or females anticipating pregnancy during study period
• Patients currently enrolled in another interventional clinical study that has not reached the primary endpoint assessment point, or (for pivotal cohort) patients who have previously had an alfapump implanted
• Immuno-modulatory treatment (including azathioprine, methotrexate, anti-TNF therapies) used within last 4 months (corticosteroids at stable dose over the last 4 months but \< 15 mg/day, or in tapering doses are allowed)
• Known or suspected hepatic or extra hepatic malignancy (other than skin cancer and in-situ cancers), unless adequately treated or in complete remission for ≥ 3 years
• History of bladder cancer
• BMI\>40 presenting a risk for technical difficulties for surgery or catheter implantation
• Contraindications to general anesthesia
• Comorbid condition or other reason (example hypertension) that may preclude stopping diuretics after enrollment

Sponsors & Collaborators

• Sequana Medical N.V.: lead

Study Sites (15)

Mayo Clinic (Arizona)

Phoenix, Arizona, 85054, United States

Location

Cedars-Sinai Comprehensive Transplant Center

Los Angeles, California, 90048, United States

Location

University of Massachusetts Memorial Medical Center

Worcester, Massachusetts, 01605, United States

Location

University of Minnesota

Minneapolis, Minnesota, 55455, United States

Location

Mayo Clinic

Rochester, Minnesota, 55905, United States

Location

Duke University

Durham, North Carolina, 27705, United States

Location

Hospital of the University of Pennsylvania

Philadelphia, Pennsylvania, 19104, United States

Location

Medical University of South Carolina

Charleston, South Carolina, 29425, United States

Location

Avera Medical Group

Sioux Falls, South Dakota, 57105, United States

Location

Methodist Dallas

Dallas, Texas, 75203, United States

Location

Baylor University Medical Center (Dallas)

Dallas, Texas, 75246, United States

Location

McGuire VA Medical Center

Richmond, Virginia, 23249, United States

Location

Medical College of Wisconsin (Froedtert)

Milwaukee, Wisconsin, 53226, United States

Location

Ottawa Hospital

Ottawa, Ontario, K1H 8L6, Canada

Location

Toronto General Hospital

Toronto, Ontario, Canada

Location

Related Publications (1)

• Wong F, Vagas HE, Reddy KR, Pagadala MR, Pocha C, Sundaram V, Bajaj JS, Shlomovitz E, Bendel E, Capel J, Kamath PS; POSEIDON Study Group. The Effects of Alfapump on Ascites Control and Quality of Life in Patients With Cirrhosis and Recurrent or Refractory Ascites. Am J Gastroenterol. 2025 Oct 1;120(10):2291-2301. doi: 10.14309/ajg.0000000000003300. Epub 2025 Jan 6.

  PMID: 39760647 DERIVED

MeSH Terms

Conditions

Ascites

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Florence Wong, MD

  Toronto General Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 31, 2019
• First Posted: June 4, 2019
• Study Start: September 16, 2019
• Primary Completion: March 30, 2024
• Study Completion: June 30, 2024
• Last Updated: December 1, 2022

Record last verified: 2022-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (13); CA (2)