Hydrustent biodegradable hydrogel ureteral stent for adults after kidney stone removal

Evaluation of the Safety and Performance of the Hydrustent® Biodegradable Hydrogel Ureteral Stent in Patients With Nephrolithiasis: A Multicentric, Randomized, Controlled Study

This will test whether the Hydrustent biodegradable hydrogel ureteral stent keeps urine flowing and is safe for adults after ureteroscopy or RIRS for kidney stones.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 134 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Hydrumedical (Industry-sponsored)
• Locations: 4 sites (Aveiro, Aveiro District and 3 other locations)
• Trial ID: NCT06719089 on ClinicalTrials.gov

What this trial studies

This is a multicenter, randomized, controlled device study with an initial 16-patient pilot phase followed by a 118-patient pivotal phase comparing Hydrustent to a standard ureteral stent. Adults who have had uncomplicated unilateral ureteroscopy (URS) or retrograde intrarenal surgery (RIRS) for ureteral or renal stones and require a postoperative stent will be randomized to receive either Hydrustent or a standard polyurethane double-loop stent. Key endpoints include safety, urinary patency, device durability (at least 24 hours), need for a secondary procedure to remove a stent, and stent-related urinary symptoms. Follow-up visits and safety monitoring are performed per protocol at the participating Portuguese centers.

Who should consider this trial

Good fit: Adults aged 18–70 with unilateral ureteral or renal stones who underwent uncomplicated URS or RIRS and have an indication for a postoperative 7 Fr double-loop ureteral stent of the available lengths are ideal candidates.

Not a fit: Patients with complicated or bilateral procedures, significant ureteral/anatomic abnormalities, children, or those outside the enrollment locations are unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, Hydrustent could maintain urinary flow after stone surgery while reducing stent-related symptoms and the need for a separate removal procedure.

How similar studies have performed: Other small studies of biodegradable ureteral stents have shown promising early results but evidence remains limited and heterogeneous, so this device approach is somewhat promising but not yet widely proven.

Eligibility criteria

Pilot phase:

Inclusion:

* Subjects with the ability to understand the requirements of the study, who have provided written ICF before any assessment is performed, and are willing to undergo all FU assessments according to the specified schedule;
* Adult patients, males or females, aged between 18 and 70 years old;
* Subjects with ureteral and/or renal stones who have undergone a successful, uncomplicated, unilateral URS and RIRS, with clinical indication to place a post-operative US, as judged by the medical investigator;
* Subjects with a height and body sizeable to accommodate a 22, 24, 26, 27 and 28 cm long US and diameter of 7 Fr, as judged by the medical investigator;
* Female participants of childbearing potential and male participants whose partner is of childbearing potential must be willing to ensure that they or their partner use protocol's recommended effective contraception methods during all the trial duration;
* Male participants must agree to refrain from donation of semen from the start of the study treatment up to the end of the study.

Exclusion:

* Subjects with urinary anatomic malformations or previous relevant surgical modifications.
* Subjects with known/suspicion of urothelial or renal tumour;
* Subjects with known/suspicion of extrinsic compression of the ureter and/or stricture;
* Subjects with known/suspicion of ureteral perforation and/or fistula;
* Subjects under active treatment for bladder outlet obstruction (e.g., benign prostatic obstruction), neurogenic bladder, overactive bladder, and/or urge urinary incontinence;
* Subjects with a solitary kidney;
* Subjects with calculated GFR below 60 mL/min/1.73m2;
* Subjects with known renal insufficiency or chronic impairment;
* Subjects with post-operative suspicion/known incomplete stone fragmentation with the presence of relevant residual urinary lithiasis, requiring an additional procedure;
* Subjects with active history of bleeding diathesis or currently taking anticoagulants (except antiplatelet agents);
* Subjects with pre-operative evidence of staghorn calculi;
* Subjects with suspicious/diagnosed UTI at the time of US placement, or pre-operative positive urine culture or active UTI taking antibiotic medication;
* Subjects with contrast allergy; Pregnant, lactating, or women of childbearing potential who do not employ a highly effective contraceptive method as judged by the medical investigator, and/or who are not willing to use a highly effective contraception for the duration of study participation;
* Subject with a known severe psychiatric disorder, substance abuse, or other reason for being unable to follow study FU instructions or unable to reliably complete patient questionnaires;
* Subjects with signs of local or systemic acute/active or chronic infections;
* Subjects with sensibility or known hypersensitivity to the implantable materials;
* Subjects with ureteral blockage or stricture;
* Subjects with failed guidewire placement or failed ureteroscopy access;
* Subjects with suspect ureteral avulsion;
* Subjects with untreated infected urinary obstruction of the kidneys (pyonephrosis);
* Subjects with vascular abnormalities of the renal pelvis outlet;
* Subjects with unexplained haematuria;
* Subjects with significant urethral obstruction;
* Subjects with concomitant or untreated bladder lithiasis;
* Any other condition that would deem a subject ineligible for treatment with the investigational device in the opinion of the medical investigator;
* Subject is known to be currently enrolled in another investigational study.

Pivotal phase:

Inclusion:

* Subjects with the ability to understand the requirements of the study, who have provided written or oral informed consent form before any assessment is performed, and are willing to undergo all FU assessments according to the specified schedule;
* Adult patients, males or females, aged \> 18 years old;
* Subjects with ureteral and/or renal stones who have undergone a successful, unilateral ureteroscopy and retrograde intra-renal surgery, with clinical indication to place a post-operative US, as judged by the medical investigator;
* Subjects with a height and body sizeable to accommodate a 22, 24, 26, 27 and 28 cm long US and diameter of 7 Fr, as judged by the medical investigator;
* Female participants of childbearing potential and male participants whose partner is of childbearing potential must be willing to ensure that they or their partner use protocol's recommended effective contraception methods during all the trial duration;
* Male participants must agree to refrain from donation of semen from the start of the study treatment up to the end of the study.

Exclusion:

* Urinary anatomic malformations or previous relevant surgical modifications;
* Subjects with known/suspicion of urothelial or renal tumour;
* Subjects with known/suspicion of extrinsic compression of the ureter and/or stricture;
* Subjects with known/suspicion of ureteral perforation and/or fistula;
* Subjects under active treatment for bladder outlet obstruction (e.g., benign prostatic obstruction), neurogenic bladder, overactive bladder, and/or urge urinary incontinence;
* Subjects with a solitary kidney;
* Subjects with calculated Glomerular Filtration Rate below 60 mL/min/1.73m2;
* Subjects with post-operative suspicion/known incomplete stone fragmentation with the presence of relevant residual urinary lithiasis, requiring an additional procedure;
* Subjects with active history of bleeding diathesis or currently taking anticoagulants (except antiplatelet agents);
* Subjects with pre-operative evidence of staghorn calculi;
* Subjects with suspicious/diagnosed urinary tract infection at the time of ureteral stent insertion, or pre-operative positive urine culture or active urinary tract infection taking antibiotic medication;
* Subjects with contrast allergy;
* Pregnant, lactating, or women of childbearing potential who do not employ a highly effective contraceptive method and/or who are not willing to use a highly effective contraception for the duration of study participation;
* Subject with a known severe psychiatric disorder, substance abuse, or other reason for being unable to follow study FU instructions or unable to reliably complete patient questionnaires;
* Subjects with signs of local or systemic acute/active or chronic infections;
* Subjects with sensibility or known hypersensitivity to the implantable materials;
* Subjects with ureteral blockage or stricture;
* Subjects with failed guidewire placement or failed ureteroscopy access;
* Subjects with suspect ureteral avulsion;
* Subjects with untreated infected urinary obstruction of the kidneys (pyonephrosis);
* Subjects with vascular abnormalities of the renal pelvis outlet;
* Subjects with unexplained haematuria;
* Subjects with significant urethral obstruction;
* Subjects with concomitant or untreated bladder lithiasis;
* Any other condition that would deem a subject ineligible for treatment with the investigational device in the opinion of the medical investigator;
* Subject is known to be currently enrolled in another investigational study.

Where this trial is running

Aveiro, Aveiro District and 3 other locations

• Unidade Local de Saúde da Região de Aveiro (ULSRA), E.P.E. — Aveiro, Aveiro District, Portugal (Recruiting)
• Unidade Local de Unidade Local de Saúde do Alto Ave (ULSAAVE), E.P.E — Guimarães, Braga District, Portugal (Recruiting)
• Hospital CUF Tejo — Lisbon, Portugal (Not_yet_recruiting)
• Unidade Local de Saúde do Alto Minho (ULSAM) — Viana do Castelo, Portugal (Not_yet_recruiting)

Study contacts

• Study coordinator: Ferreira (Sponsor)

Conditions Urinary Lithiasis; Biodegradable ureteral stent; kidney stones; Hydrustent; Hydrumedical