Silicone vs Non-Silicone Stents for Kidney Stones

(BLUES Trial)

No longer recruiting at 12 trial locations

Overseen By Elaina Shoemaker

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Michigan

Disqualifiers: Anatomical anomalies, Urinary diversion, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 5 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 3

Duration: 7 to 10 days

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests two types of stents used after ureteroscopy, a procedure for treating kidney stones. The researchers aim to determine if a silicone stent performs better than a non-silicone stent for individuals with kidney stones. Participants will receive one of the stents and report their post-procedure experiences. This trial suits those diagnosed with kidney stones on one side and planning to undergo ureteroscopy. As an unphased trial, it offers participants the chance to contribute to valuable research that could enhance future kidney stone treatments.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that these stents are safe for kidney stone treatment?

Research has shown that silicone ureteral stents, such as the Imajin stent, are generally safe. They typically cause less pain and fewer urinary issues than other stent types. Studies have not identified any major problems with silicone stents.

For stents made from other materials, research also supports their safety, though they may cause more discomfort than silicone stents. Many patients experience symptoms like frequent urination or urgency, but these are usually manageable.

Both silicone and non-silicone stents are considered safe, but silicone stents may offer a more comfortable experience. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about these treatments for kidney stones because they explore the potential benefits of different stent materials. Unlike traditional stents, which are often made of materials like polyurethane, this trial is examining whether silicone stents, like the Coloplast Imajin Hydro, could offer improved patient comfort and effectiveness. Silicone is known for its flexibility and biocompatibility, which might reduce irritation and complications. By comparing these materials directly, researchers hope to discover which type of stent offers the best outcomes for patients undergoing ureteroscopy for kidney stones.

What evidence suggests that this trial's stents could be effective for kidney stones?

This trial will compare silicone ureteral stents with non-silicone ureteral stents for patients with kidney stones. Research has shown that silicone ureteral stents, which participants in one arm of this trial may receive, might be better for patients. Studies have found that silicone stents cause less discomfort and pain than non-silicone ones. Specifically, patients with silicone stents reported less pain two weeks before their stent removal. Additionally, silicone stents are recommended for patients with kidney stones due to fewer side effects. Non-silicone stents, such as those made from polyurethane, remain common but might not be as comfortable. Overall, early findings suggest that silicone stents could offer a more comfortable option for those treated for kidney stones. ^{1 3 6 7 8}

Who Is on the Research Team?

Khurshid Ghani, MD, MS, FRCS

Principal Investigator

University of Michigan

Are You a Good Fit for This Trial?

The BLUES trial is for individuals with kidney or ureter stones who can take oral medication and are willing to follow the study's procedures. They must have stones no larger than 2cm, need a stent without a string after surgery, and be able to complete surveys. Pregnant women, those allergic to polyurethane or silicone, with certain anatomical anomalies or prior urinary diversions cannot participate.

Inclusion Criteria

I am willing and able to follow all study rules and attend all appointments.

I am scheduled for a procedure to examine my ureter with stent placement without a stent string.

My kidney stones are located only in my kidneys or ureters.

Exclusion Criteria

I need a follow-up procedure to remove leftover kidney stone pieces after surgery.

I have had surgery to redirect urine flow.

You have a tube in your ureter before the procedure.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are randomly assigned to receive either the Imajin silicone stent or a non-silicone stent after ureteroscopy

7 to 10 days

1 visit (in-person)

Follow-up

Participants complete questionnaires and have follow-up information collected to assess outcomes

60 days

2 visits (in-person), additional virtual follow-ups

What Are the Treatments Tested in This Trial?

Interventions

• Non-silicone (Polyurethane/Percuflex) ureteral stent (any manufacturer)
• Silicone (Coloplast Imajin Hydro) ureteral stent
• Ureteroscopy

Trial Overview This study compares two types of ureteral stents: Imajin silicone stents versus non-silicone polyurethane stents in patients undergoing ureteroscopy for stone removal. Participants will be randomly assigned one type of stent and asked to fill out questionnaires about their experience.

How Is the Trial Designed?

Group I: Silicone (Coloplast Imajin Hydro) ureteral stent Experimental Treatment 1 Intervention

Group II: Non-silicone (Polyurethane/Percuflex) ureteral stent (any manufacturer). Experimental Treatment 1 Intervention

Ureteroscopy is already approved in European Union, United States, Canada, Japan for the following indications:

Approved in European Union as Ureteroscopy for:

• Renal calculi
• Ureteral calculi
• Upper urinary tract calculi
• Nephrolithiasis
• Ureteral obstruction

Approved in United States as Ureteroscopy for:

• Kidney stones
• Ureteral stones
• Urinary tract obstruction
• Hematuria
• Ureteral tumors

Approved in Canada as Ureteroscopy for:

• Renal calculi
• Ureteral calculi
• Upper urinary tract calculi
• Nephrolithiasis
• Ureteral obstruction

Approved in Japan as Ureteroscopy for:

• Kidney stones
• Ureteral stones
• Urinary tract obstruction
• Hematuria
• Ureteral tumors

Who Is Running the Clinical Trial?

University of Michigan

Lead Sponsor

Trials

1,891

Recruited

6,458,000+

Coloplast A/S

Industry Sponsor

Trials

155

Recruited

14,800+

Founded

1957

Headquarters

Humlebæk, Denmark

Known For

Intimate Healthcare Solutions

Top Products

Ostomy bags, Continence products, Wound dressings

Kristian Villumsen

Coloplast A/S

Chief Executive Officer since 2018

Master's degree in Political Science from Aarhus University

Preeti Jain

Coloplast A/S

Chief Medical Officer since 2023

MD from University of Copenhagen

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT05026710

Better Lithotripsy and Ureteroscopy Evaluation of Stenting ... The trial hypothesizes that a ureteral stent made of silicone, will have superior outcomes when compared to non-silicone stents. Official Title. Better ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9142971/

Silicone vs. Polyurethane Stent: The Final Countdown - PMC The Contour ureteral stent, a soft polymer, was compared in a randomised control study to the Percuflex stent, in 130 patients needing stent ...

3. urologytimes.com urologytimes.com/view/john-michael-dibianco-md-on-silicone-vs-polyurethane-stents-for-patients-with-kidney-stones

John Michael DiBianco, MD, on silicone vs polyurethane ... A study presented at the 40th Annual European Association of Urology Congress in Madrid, Spain, compared outcomes with silicone vs polyurethane stents.

4. clinicaltrials.gov clinicaltrials.gov/study/NCT06749652

Prospective, Randomized Trial Comparing Soft and Firm ... The goal of this clinical trial is to evaluate whether ureteral stent type impacts stent-related symptoms and quality of life in patients undergoing ...

5. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6998278/

Comparison of silicone versus polyurethane ureteral stents Compared to polyurethane ureteral stents, silicone ureteral stents are associated with lower body pain intensity assessed by VASP 2 weeks before stent removal.

6. sciencedirect.com sciencedirect.com/science/article/pii/S2666168323001829

Comparison of the Removal Efficiency and Safety ... Magnetic ureteral stents have the advantages of a shorter removal time, less pain during removal, and low cost in comparison to conventional stents.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC2808646/

Ureteral stent discomfort: Etiology and management - PMC Stent-related symptoms have a high prevalence and may affect over 80% of patients. They include irritative voiding symptoms including frequency, urgency, ...

8. frontiersin.org frontiersin.org/journals/surgery/articles/10.3389/fsurg.2021.764167/full

Developments in Ureteral Stent Technology The purpose of this review is to give a brief history of ureteral stent development and summarize the recent developments in ureteral stent designs.