NephrolithiasisPhase 4ALFA-URSNCT07124299
Alpha-Blockers Prior to Ureteral Access Sheath Placement in Flexible Ureteroscopy: A Randomized Prospective Study
A Phase 4 study testing Experimental: Alpha-blocker group in people with Nephrolithiasis and Alpha Blocker, run by Pedro de Figueiredo Buchalla at 1 site in Brazil.
Trial summary
This study aims to evaluate whether the use of alpha-blockers before flexible ureterorenolithotripsy facilitates the passage of the ureteral access sheath. The trial will enroll adult patients diagnosed with kidney stones who are scheduled for flexible ureteroscopy. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Nephrolithiasis, Alpha Blocker, Ureteral Access Sheath
- What is being tested?
- Experimental: Alpha-blocker group
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 140 participants
- Where
- 1 siteBrazil
- Study dates
- 1 Jan 2024to 1 Feb 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥ 18 years
- Diagnosis of nephrolithiasis with surgical indication for flexible ureterorenolithotripsy
- Ability to provide written informed consent
Who cannot join
- Age < 18 years
- Pregnancy
- History of ureteral stricture, prior ureteral reconstructive surgery, and/or abdominal or pelvic radiotherapy
- Prior ureteroscopy or ipsilateral double-J stent placement within the past 3 months
- Chronic use of alpha-blockers for benign prostatic hyperplasia or medical expulsive therapy for ureteral stones
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Brazil1 site, 1 recruiting
- Recruiting
Centro Universitário FMABC
Santo André, São Paulo, 09060-870
Pedro Buchalla, +5516997704207, pedrofbuchalla@gmail.com
About this study
Official title: Prospective, Randomized Study on the Efficiency of Alpha-Blockers Prior to Ureteral Sheath Placement in Flexible Ureterolithotripsy
This study aims to evaluate whether the use of alpha-blockers before flexible ureterorenolithotripsy facilitates the passage of the ureteral access sheath. The trial will enroll adult patients diagnosed with kidney stones who are scheduled for flexible ureteroscopy. Participants will be randomly assigned to receive or not receive alpha-blockers for seven days before surgery. The primary outcome is the rate of successful sheath placement without the need for a second procedure. Secondary outcomes include the incidence of ureteral injuries and the need for additional surgical interventions. The goal is to improve surgical efficiency and patient outcomes in the treatment of kidney stones.
- Conditions
- Nephrolithiasis, Alpha Blocker, Ureteral Access Sheath
- Being tested
- Experimental: Alpha-blocker group, No intervention (observational study)
- Medical subject headings
- Nephrolithiasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Experimental: Alpha-blocker groupDrug
Participants in the experimental arm will receive an oral alpha-blocker (tamsulosin 0.4 mg) once daily for 7 consecutive days before undergoing flexible ureterorenolithotripsy. The medication is intended to relax ureteral smooth muscle fibers, potentially facilitating the insertion of the ureteral access sheath and reducing the need for a secondary procedure. The dose, route, and timing are standardized for all participants in this arm.
No intervention (observational study)Drug
Participants in this arm will undergo flexible ureterorenolithotripsy without receiving any alpha-blocker prior to surgery. All other perioperative care and surgical procedures will follow the same protocol as the experimental group.
| Study group | Role | What they receive |
|---|---|---|
| Experimental: Alpha-blocker group | Active comparator | Participants will receive an alpha-blocker (e.g., tamsulosin 0.4 mg orally once daily) for 7 consecutive days prior to flexible ureterorenolithotripsy. The medication aims to relax the ureteral smooth muscle and facilitate the insertion of the ureteral access sheath during surgery. All surgical procedures will follow the standard protocol used in the participating hospitals. Receives: Drug: Experimental: Alpha-blocker group |
| No Intervention: Control group | Placebo comparator | Participants will undergo flexible ureterorenolithotripsy without the use of alpha-blockers prior to surgery. All other aspects of perioperative care and surgical technique will be identical to those of the experimental group. Receives: Drug: No intervention (observational study) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Reduction in the failure rate of ureteral access sheath insertion with preoperative tamsulosin use
Measured: During the surgical procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Aug 2025
- Study start1 Jan 2024
- Primary completion1 Jan 2026 (estimated)
- Study completion1 Feb 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for NephrolithiasisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 140 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Pedro de Figueiredo Buchalla
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Pedro de Figueiredo Buchalla, Centro Universitário FMABC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07124299
- Sponsor's protocol ID
- FMABC-ALFAURS-2025-01
- Acronym
- ALFA-URS
- Status last verified
- May 2025
- First submitted
- 9 Aug 2025
- Last updated
- 15 Aug 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 15 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prospective, Randomized Study on the Efficiency of Alpha-Blockers Prior to Ureteral Sheath Placement in Flexible Ureterolithotripsy
- ClinicalTrials.gov ID
- NCT07124299
- Acronym / sponsor ID
- ALFA-URS / FMABC-ALFAURS-2025-01
- Conditions
- Nephrolithiasis, Alpha Blocker, Ureteral Access Sheath
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 140 participants (estimated)
- Lead sponsor
- Pedro de Figueiredo BuchallaUniversity, hospital or other
- Study start
- 1 Jan 2024 (actual)
- Primary completion
- 1 Jan 2026 (estimated)
- Study completion
- 1 Feb 2026 (estimated)
- First posted
- 15 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to evaluate whether the use of alpha-blockers before flexible ureterorenolithotripsy facilitates the passage of the ureteral access sheath. The trial will enroll adult patients diagnosed with kidney stones who are scheduled for flexible ureteroscopy. Participants will be randomly assigned to receive or not receive alpha-blockers for seven days before surgery. The primary outcome is the rate of successful sheath placement without the need for a second procedure. Secondary outcomes include the incidence of ureteral injuries and the need for additional surgical interventions. The goal is to improve surgical efficiency and patient outcomes in the treatment of kidney stones.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Experimental: Alpha-blocker group | Active comparator | Drug: Experimental: Alpha-blocker groupParticipants will receive an alpha-blocker (e.g., tamsulosin 0.4 mg orally once daily) for 7 consecutive days prior to flexible ureterorenolithotripsy. The medication aims to relax the ureteral smooth muscle and facilitate the insertion of the ureteral access sheath during surgery. All surgical procedures will follow the standard protocol used in the participating hospitals. |
| No Intervention: Control group | Placebo comparator | Drug: No intervention (observational study)Participants will undergo flexible ureterorenolithotripsy without the use of alpha-blockers prior to surgery. All other aspects of perioperative care and surgical technique will be identical to those of the experimental group. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Age ≥ 18 years
- Diagnosis of nephrolithiasis with surgical indication for flexible ureterorenolithotripsy
- Ability to provide written informed consent
Key exclusion criteria (5 listed)
- Age < 18 years
- Pregnancy
- History of ureteral stricture, prior ureteral reconstructive surgery, and/or abdominal or pelvic radiotherapy
- Prior ureteroscopy or ipsilateral double-J stent placement within the past 3 months
- Chronic use of alpha-blockers for benign prostatic hyperplasia or medical expulsive therapy for ureteral stones
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Experimental: Alpha-blocker groupParticipants in the experimental arm will receive an oral alpha-blocker (tamsulosin 0.4 mg) once daily for 7 consecutive days before undergoing flexible ureterorenolithotripsy. The medication is intended to relax ureteral smooth muscle fibers, potentially facilitating the insertion of the ureteral access sheath and reducing the need for a secondary procedure. The dose, route, and timing are standardized for all participants in this arm. | Drug | Experimental: Alpha-blocker group |
| No intervention (observational study)Participants in this arm will undergo flexible ureterorenolithotripsy without receiving any alpha-blocker prior to surgery. All other perioperative care and surgical procedures will follow the same protocol as the experimental group. | Drug | No Intervention: Control group |
Primary outcome
Reduction in the failure rate of ureteral access sheath insertion with preoperative tamsulosin use
Time frame: During the surgical procedure
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Aug 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Experimental: Alpha-blocker group in people with Nephrolithiasis and Alpha Blocker, run by Pedro de Figueiredo Buchalla at 1 site in Brazil.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 15 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Pedro FB Buchalla, MD (+5516997704207, pedrofbuchalla@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Reduction in the failure rate of ureteral access sheath insertion with preoperative tamsulosin use (time frame: During the surgical procedure). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Aug 2025.