An interventional study of Biodegradable double loop ureteral stent and PolyUrethane Double Loop Ureteral Stent in Urinary Lithiasis, sponsored by Hydrumedical. Recruiting at 4 sites in Portugal. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-29.
Sponsored by Hydrumedical · Not applicable, Interventional, and Treatment
The goal of this clinical investigation is to evaluate whether the Hydrustent® medical device is safe and if maintain the urinary flow inside the ureter in adults.
The main questions it aim to answer are:
Researchers will compare the Hydrustent® medical device to a comparator (a standard medical device used in clinical practice) to determine whether Hydrustent® is at least non-inferior in terms of safety and efficacy.
Other questions that the study will answer are:
Participants will:
Multicentric, randomized, controlled clinical study comprising both phases of the pre-market device clinical development stage: pilot and pivotal. The first exploratory phase of the study (16 participants) will assess the safety of Hydrustent® for the first time in humans, while providing preliminary results on its efficacy. Following this, the second phase is confirmatory (118 participants), allowing the collection of the information necessary to evaluate the clinical performance and safety of Hydrustent®.
253 studies on the registry are indexed under Urolithiasis; 67 are open to participants now.
This study's planned enrollment of 134 is above the median of 100 across 182 interventional studies indexed under Urolithiasis.
Browse Urolithiasis studies →Hydrumedical is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Pilot phase:
Inclusion:
Exclusion:
Pivotal phase:
Inclusion:
Exclusion:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Device: PolyUrethane Double Loop Ureteral Stent
Device: Biodegradable double loop ureteral stent
This ureteral stent is based on natural polymers and degrades inside the human body without causing obstruction, avoiding the need of a second surgery for stent removal and minimizing complications related to encrustation and bacterial infections.
This ureteral stent is a double J made of 100% polyurethan, heat-sensitive and radiopaque for excellent patient tolerance and high incrustation resistance.
Primary safety endpoint assessed through adverse events and device deficiencies (Pilot and pivotal phases)
Evaluation of the number, severity, and intensity of AEs and DDs at least possibly related to either the investigational device or the comparator device that occurred within 28±1 days of stent placement.
Time frame: From surgery to the end of treatment at day 28
Primary efficacy outcome assessed by the urine drainage after stent placement (Pivotal phase)
Urine patency will be assessed using a composite endpoint based on the following criteria: 1. Diuresis (range within 0.5 to 1.5 mL/kg/h). 2. Creatinine levels in blood tests (range within 0.7 to 1.2 mg/dL for men and 0.5 to 1.0 mg/dL for women). 3. CT scan to assess the adequate upper urinary tract urine drainage (defined as the absence of significative hydronephrosis) 4. Lack of surgical intervention in the stented ureter.
Time frame: From surgery to day 1
Overall clinical success (efficacy) by evaluating the urine drainage after stent placement (Pilot phase)
Urine patency will be assessed using a composite endpoint based on the following criteria: 1. Diuresis (range within 0.5 to 1.5 mL/kg/h). 2. Creatinine levels in blood tests (range within 0.7 to 1.2 mg/dL for men and 0.5 to 1.0 mg/dL for women). 3. CT scan to assess the adequate upper urinary tract urine drainage (defined as the absence of significative hydronephrosis) 4. Lack of surgical intervention in the stented ureter.
Time frame: From surgery to the end of treatment at day 28
Overall clinical success by evaluating the urine drainage after stent placement (Pivotal phase)
Urine patency will be assessed using a composite endpoint based on the following criteria: 1. Creatinine levels in blood tests (range within 0.7 to 1.2 mg/dL for men and 0.5 to 1.0 mg/dL for women). 2. CT scan to assess the adequate upper urinary tract urine drainage (defined as the absence of significative hydronephrosis) 3. Lack of surgical intervention in the stented ureter.
Time frame: From surgery to the end of treatment at day 28
Overall safety assessed through adverse events and device deficiencies (Pilot and pivotal phases)
Evaluation of the number, severity, and intensity of AEs at least possibly related to the devices occurring and number, type and severity of DDs.
Time frame: From surgery to the end of study at day 90
Assessment of the durability of the experimental device (Pilot and pivotal phases)
Presence of an intact device with no radiographic evidence of breakage or dissolution assessed by radiological assessment
Time frame: Day 1
Technical success of the experimental device (Pilot and pivotal phases)
Complete degradation of the investigational stent as measured by radiological assessment (CT scan).
Time frame: Day 28
Devices tolerability through the assessment of urinary symptoms (Pilot and pivotal phases)
Assessment of urinary symptoms via the Ureteral Stent Symptom Questionnaire (USSQ). The total score of the questionnaire is the sum of all items across the following symptom sections: urinary symptoms, pain, sexual issues, general health, and work performance. A higher total score reflects a greater burden of symptoms and worse quality of life.
Time frame: Screening phase, during the treatment phase and up to the end of the study at day 90
Devices tolerability through the assessment of urinary symptoms (Pilot and pivotal phases)
Assessment of urinary symptoms via the Visual Analog Scale (VAS). Study participants mark their symptom intensity on a continuous line 10 centimetres long, the extremes of which indicate "no pain" and "maximum pain". A higher score indicates greater pain intensity.
Time frame: Screening phase, during the treatment phase and up to the end of the study at day 90
Devices tolerability through the assessment of urinary symptoms (Pilot and pivotal phases)
Assessment of urinary symptoms via the need of pain medication. If intervention for pain management is required, it suggests that the urinary symptoms are more severe.
Time frame: During the treatment phase and up to the end of the study at day 90
Devices tolerability through the assessment of urinary symptoms (Pilot and pivotal phases)
Assessment of urinary symptoms via the International Index of Erectile Function (IIEF-5) for male participants. The 5-item tool, with each item scored from 1 to 5, generates a total score ranging from 5 to 25 points. Lower scores indicate poorer sexual functioning, while higher scores reflect better erectile functioning.
Time frame: Screening phase, during the treatment phase and up to the end of the study at day 90
Devices tolerability through the assessment of urinary symptoms (Pilot and pivotal phases)
Assessment of urinary symptoms via the International Prostate Symptom Score (IPSS) for male participants. The questionnaire consists of two sections: fhe first section includes a 7-item tool, with each item scored from 0 to 5, generating a total score ranging from 0 to 35 points. The second section assesses quality of life, with scores ranging from 0 to 6. Lower scores indicate fewer urinary symptoms and better quality of life related to urinary symptoms.
Time frame: Screening phase, during the treatment phase and up to the end of the study at day 90
Plan to share: No
No publications or documents are linked to this record.
Started Sep 2025 (actual). Primary completion is estimated for Dec 2026, 15 months after the start.
Of 96 interventional studies with no phase under Urolithiasis, half reached primary completion within 19 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 39. This study's planned 15 months is below that.
How these figures are worked out, and which studies are left out of them.
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