Clinical Evaluation of BackStop in Patients Undergoing Intraureteric Stone Lithotripsy

This study has been completed.
Information provided by:
Pluromed, Inc. Identifier:
First received: May 1, 2009
Last updated: May 4, 2009
Last verified: May 2009

The purpose of this clinical study is to evaluate BackStop, a polymer-based device that is intended to be used during ureteroscopic lithotripsy to prevent retrograde stone migration. It is a water soluble polymer with reverse thermosensitive properties; the polymer exists as a liquid at low temperature (below 17 C) and rapidly transitions to a high viscosity gel at body temperature (i.e. in the ureter). BackStop is injected above the stones in the ureter and is intended to prevent retrograde migration of stones during ureteroscopic lithotripsy. Upon completion of the lithotripsy procedure, BackStop dissolves naturally or by irrigation.

The study hypothesis is that a greater proportion of patients will experience no retropulsion of a kidney stone when BackStop is used versus no anti-retropulsion device when undergoing intracorporeal lithotripsy.

Condition Intervention
Renal Calculi
Kidney Stones
Device: BackStop
Device: Intracorporeal lithotripsy without the use of an anti-retropulsion device

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
Primary Purpose: Supportive Care
Official Title: A Randomized, Controlled, Prospective, Single Blind Clinical Evaluation of BackStop in Patients Undergoing Intraureteric Stone Lithotripsy.

Resource links provided by NLM:

Further study details as provided by Pluromed, Inc.:

Primary Outcome Measures:
  • Ability of BackStop™ to minimize migration stone fragments in the proximal ureter will and reported as "yes" or "no". [ Time Frame: intra-operative ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Extent of residual fragments remaining in ureter at the follow-up visit 2 to 4 weeks post-procedure. [ Time Frame: one month ] [ Designated as safety issue: No ]
  • In the event that stone fragments migrate retrograde, there may be a need for the physician to employ additional procedures [ Time Frame: one month ] [ Designated as safety issue: No ]

Enrollment: 68
Study Start Date: February 2008
Study Completion Date: December 2008
Primary Completion Date: November 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: BackStop
Intracorporeal lithotripsy with the use of an anti-retropulsion device.
Device: BackStop
BackStop in a gel plug that potentially prevents retropulsion during intracorporeal lithotripsy.
Active Comparator: Control
No anti-retropulsion device will be used during lithotripsy.
Device: Intracorporeal lithotripsy without the use of an anti-retropulsion device


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Patient with a solitary, radio-opaque ureteral stone in the proximal ureter.
  • Clinical indication for treatment by ureteroscopic lithotripsy.
  • Minimum 18 years old (or any institutional age limits for participation in clinical study).
  • Patients must be willing and able to participate in any follow-up visits, as required.
  • Patients must provide informed consent.

Exclusion Criteria:

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00893282

Canada, Quebec
McGill University Health Center
Montreal, Quebec, Canada, H3A1A1
Sponsors and Collaborators
Pluromed, Inc.
  More Information

Responsible Party: James Wilkie, Vice President, Operations, Pluromed, Inc. Identifier: NCT00893282     History of Changes
Other Study ID Numbers: BSTP-001 
Study First Received: May 1, 2009
Last Updated: May 4, 2009
Health Authority: Canada: Health Canada

Keywords provided by Pluromed, Inc.:

Additional relevant MeSH terms:
Kidney Calculi
Kidney Diseases
Pathological Conditions, Anatomical
Urinary Calculi
Urologic Diseases processed this record on May 26, 2016