Kidney StonesNCT02028559
Safety and Effectiveness of the Ultrasonic Propulsion of Kidney Stones
A study testing Propulse 1 with C5-2 probe and Propulse 1 with SC-X probe in people with Kidney Stones and Nephrolithiasis, run by University of Washington at 2 sites in United States.
Trial summary
This study tests moving kidney stones using focused ultrasound (referred to as ultrasonic propulsion). The study includes multiple population groups to investigate the ability of our technology to: a) move stone fragments to a location within the kidney to improve their chances of passage, and thus reduce the… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Kidney Stones, Nephrolithiasis, Urolithiasis
- What is being tested?
- Propulse 1 with C5-2 probe and Propulse 1 with SC-X probe
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 172 participants
- Where
- 2 sitesUnited States
- Study dates
- 17 Dec 2013to 31 May 2026
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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
- Individuals suspected of having at least one kidney stone. This includes:
- Patients who are being managed with watchful waiting or medical therapy
- Patients who recently (but > 4 weeks) underwent lithotripsy treatment of their stones
- Patients scheduled for lithotripsy treatment
- Or
- Individuals suspected of having an obstructed stone. This includes:
Show all 24Show fewer
- Patients presenting with renal colic
- Patients presenting with hydronephrosis or dilation of the ureter
- Primary Exclusion Criteria for all groups:
- Individuals under 18 years of age
- Individuals with non-echogenic stones
- Individuals unable or unwilling to comply with the follow-up requirements
- Individuals with a coagulation abnormality or taking blood thinners or other anticoagulant at clinically significant levels
- Individuals with mobility issues who are unable to comfortably lie for up to 30 minutes or roll from their back to their side
- Individuals belonging to a vulnerable group (pregnant, mentally disabled, physically disabled, prisoner, etc.)
- Individuals who have already received four previous ultrasonic propulsion procedures.
- Individuals who have received an ultrasonic propulsion treatment within the last 4 weeks.
- Additional Exclusion Criteria for Obstructing Stone population
- Individuals with a suspicion of kidney infection or exhibiting signs of sepsis
- Individuals whom the treating physician considers to be at high risk for serious alternate diagnoses such as acute infectious etiologies (e.g. cholecystitis, appendicitis), aortic aneurysm and rupture, or bowel disorders.
- Individuals who have undergone renal transplant, or individuals who will undergo dialysis.
- Individuals with bilateral hydronephrosis
- Individuals with a single kidney
- Individuals who have already received an ultrasonic propulsion investigative treatment for the same obstructing stone
Who cannot join
None listed.
Trial locations and contacts
2 sites in 1 country.
United States2 sites
VA Puget Sound Health Care System
Seattle, Washington, 98108
University of Washington Department of Urology
Seattle, Washington, 98195
About this study
This study tests moving kidney stones using focused ultrasound (referred to as ultrasonic propulsion). The study includes multiple population groups to investigate the ability of our technology to: a) move stone fragments to a location within the kidney to improve their chances of passage, and thus reduce the occurrence of additional symptomatic events and retreatment or b) move a symptomatic stone to relieve symptoms and pain.
Read the detailed description
This is an investigator initiated, NIH-funded study conducted by the University of Washington (UW). Our research group has developed a new, non-invasive technology using low intensity focused ultrasound to reposition kidney stones by imparting sufficient acoustic energy to physically move a stone. The focused ultrasound pulses are similar to pulses that may be used in elastography or acoustic radiation force imaging. Like conventional ultrasound, the probe is placed in contact with the patient's skin to image the stone following standard ultrasound imaging procedure. The same probe is then used to focus the ultrasound and apply a burst (a sequence of pulses) of acoustic force to push the stone. Brightness mode (B-mode) imaging is interleaved with the "pushing" pulses (Push-mode) to monitor stone movement. The user controls the burst amplitude. To limit heating at the probe surface, there is a slight delay before the operator can execute the next push.
In addition to undergoing the investigational procedure, the research activities include the following:
- subjects undergo a pain questionnaire before and after the procedure and report their current level of stone pain on a scale of 0 (no pain) to 10 (worst possible pain);
- the subject's skin in the area of probe placement is observed before and after the procedure;
- subjects are contacted once-a-week for 3 weeks to evaluate for potential adverse events, pain medication use, and, if applicable, stone passage;
- subjects are requested to undergo at least one follow-up imaging 4 - 12 weeks post-procedure;
- a review of each subject's medical records is conducted 90-days post-procedure to evaluate for additional effectiveness and safety events.
- Specifically for the residual fragment population (randomized control trial), subjects are contacted every 6 months for 3 years and their electronic medical record is reviewed for 5 years for stone growth, symptomatic, unscheduled medical visits, and surgery related to stones.
Subjects that qualify for the trial are recruited into different study arms (referred to as Population groups) based on their type of stone condition (de novo stone versus post-lithotripsy fragment), size of stone (≤ 5 mm or > 5 mm), and management plan (clinical observation or surgical intervention). The objectives vary based upon the Population group. Subjects may qualify for more than one population group and may undergo the investigational procedure up to 4 times total (inclusive of both the left and right-side urinary tracts). Subjects can only be enrolled in one population group at a time, there is a separate consent for each study population, and each study population is considered independent of the other groups. Recruitment into all population groups has been completed.
- First-in-Human Population: This was the initial group of subjects included under this clinical trial. This was a 15-subject feasibility study that included a broad range of populations. This feasibility population formulated the basis for expanding the trial into a larger study addressing each population separately. This is encompassed in subject populations 2-5 below.
- De Novo Small Stone Population: Subjects undergo the investigational procedure awake and in the clinic. To qualify the subject must have a de novo stone ≤ 5 mm in largest dimension. Ultrasonic propulsion is used with the intent to help facilitate stone passage. If the stone is larger than 5 mm, subjects could be recruited into the URS subject population (see bullet point #3 below).
- Concurrent with URS Population: Subjects undergo the investigational procedure while anesthetized and concurrently undergoing a ureteroscopy guided laser lithotripsy procedure (referred to herein as URS). To qualify the subject must have at least one stone ≤ 20 mm in the largest dimension and be scheduled for surgery. Ultrasonic propulsion may be used to move a de novo stone or stone fragments of varying sizes generated over the course of the URS procedure. Note that since these subjects are anesthetized, a pain questionnaire is not included as part of their protocol.
- Obstructing Stone Population: Subjects undergo the investigational procedure awake and in the clinic or emergency department (ED) setting. To qualify the subject must have clinical imaging confirmation of an obstructing stone with their pain managed and complete a urinalysis to for assess infection risk. Ultrasonic propulsion is used with the intent to relieve the obstruction and associated pain. A subset of subjects were exposed to higher amplitude dislodging pulses, in addition to the ultrasonic propulsion pulses.
- Residual Fragment Population: Subjects undergo the investigational procedure awake and in the clinic setting. To qualify the subject must have at least one post-lithotripsy residual fragment (≤ 5 mm in largest dimension) identified either on imaging or based on the investigator's interpretation of that imaging. This is a prospective, open-label, multicenter, randomized control trial (RCT) with a treatment arm and control arm. The only difference in protocol between the two arms is that only the treatment group undergoes the investigational procedure and the associated post-procedure pain questionnaire and the post-procedure skin surface inspection. Ultrasonic propulsion is used with the intent to demonstrate: a) the ability of the ultrasonic propulsion device to reposition stones within the human kidney, b) the subsequent clinical benefit of facilitating stone passage and reducing stone burden, and c) the subsequent clinical benefit of reducing relapse. This is the only population group recruited across more than one site - the UW and the VA Puget Sound Healthcare System.
- Conditions
- Kidney Stones, Nephrolithiasis, Urolithiasis
- Being tested
- Propulse 1 with C5-2 probe, Propulse 1 with SC-X probe
- Keywords
- stones, kidney, stone fragments, lithotripsy
- Medical subject headings
- Kidney Calculi, Nephrolithiasis, Urolithiasis, Calculi
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Propulse 1 with C5-2 probeDevice
Move kidney stones with Propulse 1 device.
Propulse 1 with SC-X probeDevice
Move kidney stones with Propulse 1 device.
| Study group | Role | What they receive |
|---|---|---|
| First in Human (FIH) | Experimental | Initial phase of the trial. Includes a broad spectrum of population groups (e.g. de novo, concurrent with URS, residual fragments) to demonstrate feasibility. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure conducted with the Propulse 1 device and C5-2 transducer. Subjects (n = 15) receive up to 40 push bursts. Receives: Device: Propulse 1 with C5-2 probe |
| De Novo Small Stone | Experimental | Segment of the trial focused specifically on subjects with small (≤ 5 mm) stones under observation management. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 2) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. Receives: Device: Propulse 1 with SC-X probe |
| Concurrent with URS | Experimental | Segment of the trial focused specifically on subjects undergoing ultrasonic propulsion concurrently with their ureteroscopy guided laser lithotripsy procedure. Study provides visual observation of stone motion and any potential tissue injury. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 18) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. Receives: Device: Propulse 1 with SC-X probe |
| Obstructing Stone - Pushing only | Experimental | Segment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 16) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. Receives: Device: Propulse 1 with SC-X probe |
| Residual Fragment (Treatment group) | Experimental | Segment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Treatment arm of a randomized control trial. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 54) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. Receives: Device: Propulse 1 with SC-X probe |
| Residual Fragment (Control group) | No intervention | Segment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Control arm of a randomized control trial. Subjects (n = 54) follow same protocol as Residual Fragment (Treatment group) but do not receive the ultrasonic propulsion intervention. |
| Obstructing Stone - Pushing + Dislodging | Experimental | Segment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Participants were separate from the Obstructing Stone - Pushing only based on a stone skin-to-stone distance < 8 mm. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 13) receive both Dislodging and Push bursts up to a maximum cumulative dose exposure of 5 minutes. This is the only population to receive the Dislodging bursts, which consist of higher amplitude (up to 7 MPa) and shorter duration pulses compared to pushing. The Push burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. Receives: Device: Propulse 1 with SC-X probe |
What is being measured
The primary outcome is the main question the study is designed to answer.
Measurement of Stone Motion Caused by Ultrasound
Percentage of study participants for which stone motion was observed on the real-time ultrasound images.
Measured: At the time of the procedure. To be evaluated with each therapy pulse over an approximately 1-hour study. Confirmed with post-procedure review of the study video.
Measurement of Stone Passage
The percentage of participants reporting visual observation of stone passage or confirmed with follow-up imaging. For the residual fragment RCT population specifically, the percentage of participants reporting visual observation of stone passage during the 3-week follow-up period after the procedure or randomization (Control group).
Measured: Measurement occurs over 3 weeks (weekly phone call or email encounter with the subject) plus review of the subject's medical chart up to the point the subject is exited from the study.
Measurement of Relapse
The percentage of participants experiencing stone relapse defined as: an unscheduled, symptomatic visit for stones on the study side, surgery for stones on the study side, or stone growth of a residual fragment measured by clinical imaging exams. This measurement is specific to the residual fragment population and associated randomized control trial. Only a single relapse event is counted per participant, though a participant could experience more than one event.
Measured: Measurement up to 5 years post-procedure. This includes a phone call or email exchange semi-annually for up to 3-years and a medical record review (including imaging) semi-annually for up to 5-years.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Jan 2014 (estimated)
- Study start17 Dec 2013
- Primary completion1 Aug 2025
- Study completion31 May 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for Kidney StonesStudies of the same condition, open and under way.
- More trials run by University of WashingtonThe sponsor's other registered studies.
- 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 N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Single group
- Model description
- Population groups 1-4 are single groups. Subjects are assigned based upon their underlying stone condition and the stage of the trial. Subjects enrolled into the residual fragment population (group 5) are randomized between a treatment group and concurrent control group.
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 172 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Washington
- Sponsor type
- University, hospital or other
- Collaborators
- VA Puget Sound Health Care System
- Responsible party
- Principal investigator, Jonathan Harper, MD, University of Washington
- Investigators
- Jonathan Harper, MD, Principal investigator, University of Washington
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02028559
- Sponsor's protocol ID
- STUDY00002746
- Status last verified
- Mar 2026
- First submitted
- 1 Jan 2014
- Last updated
- 1 Jun 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- Individual data sharing
- No
Publications
Hall MK, Thiel J, Dunmire B, Samson PC, Kessler R, Sunaryo P, Sweet RM, Metzler IS, Chang HC, Gunn M, Dighe M, Anderson L, Popchoi C, Managuli R, Cunitz BW, Burke BH, Ding L, Gutierrez B, Liu Z, Sorensen MD, Wessells H, Bailey MR, Harper JD. First Series Using Ultrasonic Propulsion and Burst Wave Lithotripsy to Treat Ureteral Stones. J Urol. 2022 Nov;208(5):1075-1082. doi: 10.1097/JU.0000000000002864. Epub 2022 Nov 1.
PubMed 36205340Dai JC, Sorensen MD, Chang HC, Samson PC, Dunmire B, Cunitz BW, Thiel J, Liu Z, Bailey MR, Harper JD. Quantitative Assessment of Effectiveness of Ultrasonic Propulsion of Kidney Stones. J Endourol. 2019 Oct;33(10):850-857. doi: 10.1089/end.2019.0340. Epub 2019 Sep 25.
PubMed 31333058Harper JD, Cunitz BW, Dunmire B, Lee FC, Sorensen MD, Hsi RS, Thiel J, Wessells H, Lingeman JE, Bailey MR. First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones. J Urol. 2016 Apr;195(4 Pt 1):956-64. doi: 10.1016/j.juro.2015.10.131. Epub 2015 Oct 30.
PubMed 26521719Sorensen MD, Dunmire B, Thiel J, Cunitz BW, Burke BH, Levchak BJ, Popchoi C, Holmes AE, Kucewicz JC, Hall MK, Dighe M, Dai JC, Cormack FC, Liu Z, Bailey MR, Porter MP, Harper JD. Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Kidney Stone Fragments vs Observation. J Urol. 2024 Dec;212(6):811-820. doi: 10.1097/JU.0000000000004186. Epub 2024 Aug 15.
PubMed 39146526Yang CC, Keating EE, Managuli R, Honssinger N, Holt SK, Desai AC. A Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Renal Stone Fragments vs Observation. J Urol. 2025 Jul;214(1):3-9. doi: 10.1097/JU.0000000000004501. Epub 2025 Mar 3.
PubMed 40030414Harper JD, Metzler I, Hall MK, Chen TT, Maxwell AD, Cunitz BW, Dunmire B, Thiel J, Williams JC, Bailey MR, Sorensen MD. First In-Human Burst Wave Lithotripsy for Kidney Stone Comminution: Initial Two Case Studies. J Endourol. 2021 Apr;35(4):506-511. doi: 10.1089/end.2020.0725. Epub 2020 Nov 5.
PubMed 32940089
Study at a glance
From the registry record, last updated by the sponsor on 1 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Safety and Effectiveness of the Ultrasonic Propulsion of Kidney Stones
- ClinicalTrials.gov ID
- NCT02028559
- Acronym / sponsor ID
- STUDY00002746
- Conditions
- Kidney Stones, Nephrolithiasis, Urolithiasis
- Keywords
- stones, kidney, stone fragments, lithotripsy
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 172 participants (actual)
- Lead sponsor
- University of WashingtonUniversity, hospital or other
- Collaborators
- VA Puget Sound Health Care System
- Study start
- 17 Dec 2013 (actual)
- Primary completion
- 1 Aug 2025 (actual)
- Study completion
- 31 May 2026 (estimated)
- First posted
- 7 Jan 2014 (estimated)
- Results
- Posted 1 Jun 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study tests moving kidney stones using focused ultrasound (referred to as ultrasonic propulsion). The study includes multiple population groups to investigate the ability of our technology to: a) move stone fragments to a location within the kidney to improve their chances of passage, and thus reduce the occurrence of additional symptomatic events and retreatment or b) move a symptomatic stone to relieve symptoms and pain.
Detailed description
This is an investigator initiated, NIH-funded study conducted by the University of Washington (UW). Our research group has developed a new, non-invasive technology using low intensity focused ultrasound to reposition kidney stones by imparting sufficient acoustic energy to physically move a stone. The focused ultrasound pulses are similar to pulses that may be used in elastography or acoustic radiation force imaging. Like conventional ultrasound, the probe is placed in contact with the patient's skin to image the stone following standard ultrasound imaging procedure. The same probe is then used to focus the ultrasound and apply a burst (a sequence of pulses) of acoustic force to push the stone. Brightness mode (B-mode) imaging is interleaved with the "pushing" pulses (Push-mode) to monitor stone movement. The user controls the burst amplitude. To limit heating at the probe surface, there is a slight delay before the operator can execute the next push.
In addition to undergoing the investigational procedure, the research activities include the following:
- subjects undergo a pain questionnaire before and after the procedure and report their current level of stone pain on a scale of 0 (no pain) to 10 (worst possible pain);
- the subject's skin in the area of probe placement is observed before and after the procedure;
- subjects are contacted once-a-week for 3 weeks to evaluate for potential adverse events, pain medication use, and, if applicable, stone passage;
- subjects are requested to undergo at least one follow-up imaging 4 - 12 weeks post-procedure;
- a review of each subject's medical records is conducted 90-days post-procedure to evaluate for additional effectiveness and safety events.
- Specifically for the residual fragment population (randomized control trial), subjects are contacted every 6 months for 3 years and their electronic medical record is reviewed for 5 years for stone growth, symptomatic, unscheduled medical visits, and surgery related to stones.
Subjects that qualify for the trial are recruited into different study arms (referred to as Population groups) based on their type of stone condition (de novo stone versus post-lithotripsy fragment), size of stone (≤ 5 mm or > 5 mm), and management plan (clinical observation or surgical intervention). The objectives vary based upon the Population group. Subjects may qualify for more than one population group and may undergo the investigational procedure up to 4 times total (inclusive of both the left and right-side urinary tracts). Subjects can only be enrolled in one population group at a time, there is a separate consent for each study population, and each study population is considered independent of the other groups. Recruitment into all population groups has been completed.
- First-in-Human Population: This was the initial group of subjects included under this clinical trial. This was a 15-subject feasibility study that included a broad range of populations. This feasibility population formulated the basis for expanding the trial into a larger study addressing each population separately. This is encompassed in subject populations 2-5 below.
- De Novo Small Stone Population: Subjects undergo the investigational procedure awake and in the clinic. To qualify the subject must have a de novo stone ≤ 5 mm in largest dimension. Ultrasonic propulsion is used with the intent to help facilitate stone passage. If the stone is larger than 5 mm, subjects could be recruited into the URS subject population (see bullet point #3 below).
- Concurrent with URS Population: Subjects undergo the investigational procedure while anesthetized and concurrently undergoing a ureteroscopy guided laser lithotripsy procedure (referred to herein as URS). To qualify the subject must have at least one stone ≤ 20 mm in the largest dimension and be scheduled for surgery. Ultrasonic propulsion may be used to move a de novo stone or stone fragments of varying sizes generated over the course of the URS procedure. Note that since these subjects are anesthetized, a pain questionnaire is not included as part of their protocol.
- Obstructing Stone Population: Subjects undergo the investigational procedure awake and in the clinic or emergency department (ED) setting. To qualify the subject must have clinical imaging confirmation of an obstructing stone with their pain managed and complete a urinalysis to for assess infection risk. Ultrasonic propulsion is used with the intent to relieve the obstruction and associated pain. A subset of subjects were exposed to higher amplitude dislodging pulses, in addition to the ultrasonic propulsion pulses.
- Residual Fragment Population: Subjects undergo the investigational procedure awake and in the clinic setting. To qualify the subject must have at least one post-lithotripsy residual fragment (≤ 5 mm in largest dimension) identified either on imaging or based on the investigator's interpretation of that imaging. This is a prospective, open-label, multicenter, randomized control trial (RCT) with a treatment arm and control arm. The only difference in protocol between the two arms is that only the treatment group undergoes the investigational procedure and the associated post-procedure pain questionnaire and the post-procedure skin surface inspection. Ultrasonic propulsion is used with the intent to demonstrate: a) the ability of the ultrasonic propulsion device to reposition stones within the human kidney, b) the subsequent clinical benefit of facilitating stone passage and reducing stone burden, and c) the subsequent clinical benefit of reducing relapse. This is the only population group recruited across more than one site - the UW and the VA Puget Sound Healthcare System.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 7
- Model description
- Population groups 1-4 are single groups. Subjects are assigned based upon their underlying stone condition and the stage of the trial. Subjects enrolled into the residual fragment population (group 5) are randomized between a treatment group and concurrent control group.
| Arm | Type | Receives |
|---|---|---|
| First in Human (FIH) | Experimental | Device: Propulse 1 with C5-2 probeInitial phase of the trial. Includes a broad spectrum of population groups (e.g. de novo, concurrent with URS, residual fragments) to demonstrate feasibility. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure conducted with the Propulse 1 device and C5-2 transducer. Subjects (n = 15) receive up to 40 push bursts. |
| De Novo Small Stone | Experimental | Device: Propulse 1 with SC-X probeSegment of the trial focused specifically on subjects with small (≤ 5 mm) stones under observation management. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 2) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. |
| Concurrent with URS | Experimental | Device: Propulse 1 with SC-X probeSegment of the trial focused specifically on subjects undergoing ultrasonic propulsion concurrently with their ureteroscopy guided laser lithotripsy procedure. Study provides visual observation of stone motion and any potential tissue injury. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 18) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. |
| Obstructing Stone - Pushing only | Experimental | Device: Propulse 1 with SC-X probeSegment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 16) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. |
| Residual Fragment (Treatment group) | Experimental | Device: Propulse 1 with SC-X probeSegment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Treatment arm of a randomized control trial. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 54) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. |
| Residual Fragment (Control group) | No intervention | –Segment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Control arm of a randomized control trial. Subjects (n = 54) follow same protocol as Residual Fragment (Treatment group) but do not receive the ultrasonic propulsion intervention. |
| Obstructing Stone - Pushing + Dislodging | Experimental | Device: Propulse 1 with SC-X probeSegment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Participants were separate from the Obstructing Stone - Pushing only based on a stone skin-to-stone distance < 8 mm. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 13) receive both Dislodging and Push bursts up to a maximum cumulative dose exposure of 5 minutes. This is the only population to receive the Dislodging bursts, which consist of higher amplitude (up to 7 MPa) and shorter duration pulses compared to pushing. The Push burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (24 listed)
- Individuals suspected of having at least one kidney stone. This includes:
- Or
- Individuals suspected of having an obstructed stone. This includes:
- Individuals under 18 years of age
- Individuals with non-echogenic stones
Key exclusion criteria (0 listed)
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 |
|---|---|---|
| Propulse 1 with C5-2 probeMove kidney stones with Propulse 1 device. | Device | First in Human (FIH) |
| Propulse 1 with SC-X probeMove kidney stones with Propulse 1 device. | Device | Concurrent with URS, De Novo Small Stone, Obstructing Stone - Pushing + Dislodging, Obstructing Stone - Pushing only, Residual Fragment (Treatment group) |
Primary outcome
Measurement of Stone Motion Caused by Ultrasound
Time frame: At the time of the procedure. To be evaluated with each therapy pulse over an approximately 1-hour study. Confirmed with post-procedure review of the study video.
Percentage of study participants for which stone motion was observed on the real-time ultrasound images.
Measurement of Stone Passage
Time frame: Measurement occurs over 3 weeks (weekly phone call or email encounter with the subject) plus review of the subject's medical chart up to the point the subject is exited from the study.
The percentage of participants reporting visual observation of stone passage or confirmed with follow-up imaging. For the residual fragment RCT population specifically, the percentage of participants reporting visual observation of stone passage during the 3-week follow-up period after the procedure or randomization (Control group).
Measurement of Relapse
Time frame: Measurement up to 5 years post-procedure. This includes a phone call or email exchange semi-annually for up to 3-years and a medical record review (including imaging) semi-annually for up to 5-years.
The percentage of participants experiencing stone relapse defined as: an unscheduled, symptomatic visit for stones on the study side, surgery for stones on the study side, or stone growth of a residual fragment measured by clinical imaging exams. This measurement is specific to the residual fragment population and associated randomized control trial. Only a single relapse event is counted per participant, though a participant could experience more than one event.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 1 Jun 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Results publication: PubMed 36205340Hall MK, Thiel J, Dunmire B, Samson PC, Kessler R, Sunaryo P, Sweet RM, Metzler IS, Chang HC, Gunn M, Dighe M, Anderson L, Popchoi C, Managuli R, Cunitz BW, Burke BH, Ding L, Gutierrez B, Liu Z, Sorensen MD, Wessells H, Bailey MR, Harper JD. First Series Using Ultrasonic Propulsion and Burst Wave Lithotripsy to Treat Ureteral Stones. J Urol. 2022 Nov;208(5):1075-1082. doi: 10.1097/JU.0000000000002864. Epub 2022 Nov 1.
- Results publication: PubMed 31333058Dai JC, Sorensen MD, Chang HC, Samson PC, Dunmire B, Cunitz BW, Thiel J, Liu Z, Bailey MR, Harper JD. Quantitative Assessment of Effectiveness of Ultrasonic Propulsion of Kidney Stones. J Endourol. 2019 Oct;33(10):850-857. doi: 10.1089/end.2019.0340. Epub 2019 Sep 25.
- Results publication: PubMed 26521719Harper JD, Cunitz BW, Dunmire B, Lee FC, Sorensen MD, Hsi RS, Thiel J, Wessells H, Lingeman JE, Bailey MR. First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones. J Urol. 2016 Apr;195(4 Pt 1):956-64. doi: 10.1016/j.juro.2015.10.131. Epub 2015 Oct 30.
- Results publication: PubMed 39146526Sorensen MD, Dunmire B, Thiel J, Cunitz BW, Burke BH, Levchak BJ, Popchoi C, Holmes AE, Kucewicz JC, Hall MK, Dighe M, Dai JC, Cormack FC, Liu Z, Bailey MR, Porter MP, Harper JD. Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Kidney Stone Fragments vs Observation. J Urol. 2024 Dec;212(6):811-820. doi: 10.1097/JU.0000000000004186. Epub 2024 Aug 15.
- Results publication: PubMed 40030414Yang CC, Keating EE, Managuli R, Honssinger N, Holt SK, Desai AC. A Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Renal Stone Fragments vs Observation. J Urol. 2025 Jul;214(1):3-9. doi: 10.1097/JU.0000000000004501. Epub 2025 Mar 3.
- Derived from this study: PubMed 32940089Harper JD, Metzler I, Hall MK, Chen TT, Maxwell AD, Cunitz BW, Dunmire B, Thiel J, Williams JC, Bailey MR, Sorensen MD. First In-Human Burst Wave Lithotripsy for Kidney Stone Comminution: Initial Two Case Studies. J Endourol. 2021 Apr;35(4):506-511. doi: 10.1089/end.2020.0725. Epub 2020 Nov 5.
- Link to a page at the University of Washingon Applied Physics Laboratory website that provides additional information on ultrasonic propulsion.Link provided by the sponsor.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Jonathan Harper, MD principal investigator
University of Washington
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Propulse 1 with C5-2 probe and Propulse 1 with SC-X probe in people with Kidney Stones and Nephrolithiasis, run by University of Washington at 2 sites in United States.
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 24 inclusion and 0 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: under way, not looking for participants, as of the sponsor's last update on 1 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. 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. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 1 Jun 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Measurement of Stone Motion Caused by Ultrasound (time frame: At the time of the procedure. To be evaluated with each therapy pulse over an approximately 1-hour study. Confirmed with post-procedure review of the study video.). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02028559, which also lists 6 linked publications.
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 1 Jun 2026.