Data suggest Break Wave lithotripsy is safe, effective for urolithiasis

Break wave lithotripsy appears to be safe and effective in the treatment of patients with urolithiasis, according to data from a first-in-human, prospective, international clinical trial (NCT03811171) presented at the 2024 World Congress of Endourology and Uro-Technology in Seoul, South Korea.¹

The trial enrolled a total of 44 adult patients with renal or ureteral stones.

"Break wave lithotripsy is a new minimally invasive modality that allows the treatment of stones outside of the operating room and can be done at the point of care with no anesthesia. The treatment for these patients is much easier than typical standard shockwave lithotripsy as they are not required to fast or undergo sedation or anesthesia. This will potentially change how we deal with acute kidney stones since we can now treat patients at the point of care (in the clinic or the ER) with no anesthesia with results that are similar to shockwave lithotripsy,” said presenting author Ben H. Chew, MD, MSc, FRCSC, of the University of British Columbia, in correspondence with Urology Times^®. "Stones in locations that can be visualized by ultrasound can also be treated using Break wave lithotripsy.”

In total, the trial included 44 patients, with 59% presenting with renal stones and 41% presenting with stones in the distal ureter. Patients included in the trial underwent Break Wave Lithotripsy for 30 minutes at varying dose levels up to 8 MPa of acoustic pressure.

Data showed that any stone fragmentation was achieved in 88% of patients. Of those, 70% of patients had fragments of 4 mm or smaller, 55% had fragments of 2 mm or smaller, and 49% of patients were completely stone free on CT imaging. Among all patients, 7% required retreatment with either shock wave lithotripsy or ureteroscopy.

The optimal dose setting was identified and administered to 36 of 44 patients in the trial. Among those patients, 92% achieved any stone fragmentation. Additionally, 75% of patients had stone fragments of 4 mm or smaller, and 58% of patients were stone free on CT imaging.

Of the 14 patients with stones in the lower pole, 71% had fragments of 4 mm or smaller and 29% were stone free on imaging. Of the 18 patients with stones in the distal ureter, 89% were completely stone free on imaging.

Regarding safety, no patients experience a serious adverse event (AE), hematoma, cardiac arrhythmia, nor sepsis at any dose level assessed. All patients completed the procedure.

Overall, the open-label, single-arm study enrolled 44 adult patients with renal or ureteral stones across 5 clinical trial sites in the United States and Canada. Patients were enrolled and treated with Break Wave Lithotripsy between August 2019 and February 2022.

Among all patients included in the trial, 73% (32) were male. The median age was 50 years (SD, 14). The average stone size at baseline was 6.1 mm (SD, 1.5; range, 3-9), and the average stone density was 847 HU (SD, 238; range, 450-1346).

To be eligible for enrollment, patients needed to present with at least 1 kidney stone on CT imaging. Additionally, stones needed to be within the upper urinary tract, indicated for shock wave lithotripsy per the American Urological Association (AUA) 2016 guidelines, and had to be measured under CT to be within the AUA 2016 guidelines (≤ 10 mm for lower pole stones and ≤ 20 mm for non-lower pole stones).²

Of those included in the trial, 86% received either no medication (50%) or minor analgesia (36%) (e.g., ketorolac 15-30 mg). Patients underwent Break Wave Lithotripsy with the SonoMotion Break Wave technology in either the operating room, the office/clinic, or the emergency department. Patients were followed for 90 days after the procedure.

The primary effectiveness outcome was stone fragmentation, as determined by stone passage or imaging confirmation. The primary safety outcome was the occurrence of clinically significant or symptomatic hematoma, urinary tract sepsis, or cardiac arrhythmia. Secondary effectiveness measures were stone free status and residual fragment size. The secondary safety measure was the occurrence of AEs.

Overall, the authors concluded, “Break Wave Lithotripsy appears to be a safe and effective non-invasive stone therapy requiring little to no anesthesia. It is potentially suitable for non-operative environments such as the office or ED and is being evaluated in ongoing trials.”¹

References

1. Chew BH, Harper JD, Sur RL, et al. Break WaveTM lithotripsy for urolithiasis: results of the first-in-human international multicenter clinical trial. Presented at: 2024 World Congress of Endourology and Uro-Technology. Seoul, South Korea. August 12-16, 2024. Abstract MP23-06. https://meetings.association-service.org/docs/wcet/abstracts/abstracts.aspx

2. Break Wave(TM) extracorporeal lithotripter first-in-human study. ClinicalTrials.gov. Last updated April 17, 2024. Accessed August 21, 2024. https://clinicaltrials.gov/study/NCT03811171