Calyxo Shares Clinical Data Supporting the Benefits of its CVAC System

Calyxo Inc. is touting positive results from two studies evaluating the Steerable Ureteral Renal Evacuation (SURE) procedure with its CVAC System.

Across both studies, the CVAC System demonstrated consistently high stone clearance and low residual stone volume. Topline CLEARANCE study results show 96% mean clearance and mean residual stone volume (RSV) of 14.1 mm³, independent of initial stone burden at 30 days post-procedure.¹ Two-year ASPIRE trial data, which is the first to evaluate the long-term impact of an aspiration procedure, shows significantly fewer health care consumption events (HCE; ED visits, hospitalizations, and retreatments)* with the CVAC System compared with standard ureteroscopy (URS) (3 vs. 20, p=0.0004); a 73% reduction in HCE risk (p=0.02)* and longer event-free survival with the CVAC System.² The peer‑reviewed publication of both studies in the Journal of Endourology indicates aspiration technology like the CVAC System is a clinically validated and important part of care in kidney stone treatment.

“These publications represent an important milestone not only for the CVAC System, but for the field of urology,” Calyxo CEO Joe Catanese, Ph.D., stated. “What’s most compelling is the consistency of the findings; the CVAC System delivers superior outcomes with reliably low RSV. The data show that achieving low RSV translates into meaningful long-term clinical benefits for patients. We believe this evidence defines a more rigorous standard for defining procedural success in kidney stone treatment.”

CLEARANCE is a prospective, single-arm trial designed to assess the performance of the second-generation, fully integrated CVAC System with respect to removing renal stone fragments and safety. The trial included 30 participants (32 renal units), with a total stone burden of 703.6 ± 835 mm³ (or 14.8 ± 6.4 mm linear stone burden). Topline data show that the second-generation system provides consistently high stone clearance (96.2%) and very low RSV (14.1 mm³) independent of baseline stone volume. Low RSV was maintained even with denser stones (Hounsfield Units = 1203). Postoperatively, two urinary tract infections (6.7%) were reported, both of which resolved with intravenous antibiotics. No sepsis, Grade 3 AEs, or retreatments were reported through 30 days post-procedure. This safety profile is similar to typical URS complication rates and comparable to the ASPIRE 30-day trial results.

Mean procedural time in the CLEARANCE trial was 46.4 minutes with the second-generation CVAC System compared with 66 minutes reported with the first-generation system.³ This finding validates the procedural efficiency that the second-generation CVAC System achieves by integrating direct visualization, lithotripsy, microjet irrigation, continuous flow, and active aspiration into a single device. The CVAC System is not only an all-in-one device but a high-performance aspiration technology with simultaneous irrigation and aspiration via separate channels designed for complete stone clearance. The unique mechanism of action also helps to maintain safe intrarenal pressure and temperature.^4,5

“These data demonstrate that the safety and efficacy of the second-generation CVAC System are consistent with the first-generation platform, while delivering meaningful improvements in procedural efficiency,” said Brian Eisner, M.D., chair of Urology at Tulane University School of Medicine and lead author on the CLEARANCE publication. “Taken together, these findings reinforce the improved outcomes achievable with the CVAC System and support its role as a standard of care for kidney stone removal across a broad range of stone burdens.”

ASPIRE is the first randomized controlled trial (RCT) to evaluate two-year stone removal outcomes for an aspiration procedure and the first to utilize HCE and stone events (SE) as endpoints, providing critical insights and metrics that can advance care and outcomes for patients undergoing stone removal procedures. The study included 93 participants who underwent SURE with the CVAC System or standard ureteroscopy for whom two-year data were available. Key study findings show there were significantly fewer HCE* with the CVAC System compared with URS (three vs. 20, p=0.0004) and a 73% reduction in HCE risk (p=0.02)*. Furthermore, RSV was a consistent, statistically significant predictor of HCE and SE; stone-free rate (SFR) and residual fragment counts were not predictive—highlighting the limitations of traditional, binary definitions of success. This finding mirrors the recognition in the latest AUA Guideline⁶ that stone treatment outcomes are nuanced and should incorporate volumetric measures such as residual stone burden and percent stone clearance derived from imaging.

“ASPIRE challenges how we define success in kidney stone removal,” said Thomas Chi, M.D., professor and chair for the University of Alabama at Birmingham Department of Urology, and senior author on the ASPIRE publication. “The study identifies residual stone volume as an important predictor of patient outcomes and shows that minimizing stone volume with the CVAC System can reduce unplanned hospital visits, events that carry substantial clinical and economic impact. These findings highlight the importance of minimizing residual stone burden to maximize the best possible outcome for our patients.”

The CLEARANCE and two-year ASPIRE data further demonstrate the benefits of the CVAC System. Across sponsored and independent studies, the CVAC System has consistently demonstrated low RSV independent of baseline stone burden.^7,8 Together, these findings reinforce a rigorous, patient-centered approach to kidney stone treatment, focused not only on stone clearance, but on long-term benefits.

According to the American Urological Association, approximately 10% of U.S. residents will suffer from a kidney stone at some point in their lives. Kidney stone disease is a painful condition that can result in significant healthcare costs (Current Urology Reports estimates $4.1 billion in annual direct treatment costs by 2030).

The CVAC System was cleared by the U.S. Food and Drug Administration in 2024 and enables a minimally invasive approach for kidney stone clearance. It is an all-in-one solution designed to efficiently and effectively remove kidney stones. It uses irrigation and vacuum aspiration to continuously clear stone fragments during and after laser lithotripsy, enabling physicians to achieve a stone-free outcome.

Calyxo Inc. is an innovation-driven medical device company focused on improving care for patients with kidney stones by delivering paradigm-shifting solutions that enable urologists to safely, effectively, and efficiently achieve unrivaled clinical outcomes. Learn more at calyxoinc.com.

* Limited to retreatments likely due to residual stones at the end of the procedure.

References
¹ Eisner BH, Pathak N, Sabnis R, et al. A Prospective Study of Steerable Ureteroscopic Renal Evacuation Using the Second-Generation CVAC® Aspiration System: Results from the CLEARANCE Study. J. Endourol. 2026;0(0). doi:10.1177/08927790261415603.
² Matlaga BR, Mueller TJ, Johnson B, et al. Residual Stone Volume Predicts Health Care Consumption and Stone Events: Analysis of Two-Year Results of the ASPIRE Study. J Endourolo. 2026;0(0). doi:10.1177/08927790261420565.
³ Matlaga BR, Mueller TJ, Johnson B, et al. A Prospective, Randomized, Noninferiority Study to Evaluate the Safety and Effectiveness of Steerable Ureteroscopic Renal Evacuation Compared with Standard Ureteroscopy: 30-Day Results of the ASPIRE Study. J Endourol. 2025 Jan;39(1):10-18. doi: 10.1089/end.2024.0602.
⁴ Eisner, B, IP08-05: CVAC System Maintains Consistently Low Intrarenal Pressure Independent of Ureteropelvic Junction Compliance Via Continuous Fluid Outflow, Conference Presentation, AUA 2025.
⁵ Berrios et. al. PD01-09: Impact of Steerable Ureteroscopic Renal Evacuation (SURE) Using CVAC on Intrarenal Pressure, Conference Presentation, AUA 2025.
⁶ Surgical Management of Kidney and Ureteral Stones: AUA Guideline 2026; https://www.auanet.org/guidelines-and-quality/guidelines/surgical-management-of-kidney-and-ureteral-stones
⁷ Ballantyne CC, HE Foss, JJ Cabo et al. First in-vivo multicenter experience with the novel CVAC 2.0 ureteroscope with simultaneous irrigation and aspiration functionality. World J Urol. 2025 Oct 29;43(1):645. doi: 10.1007/s00345-025-05912-x.
⁸ Cabo JJS, CC Ballantyne, VS Edmonds et al. Prospective, Real-World Evaluation of CVAC 2.0 In-Scope Aspiration System Compared with Flexible and Navigable Ureteral Access Sheath for High-Volume Stone Disease. J Endourol. 2025 Dec;39(12):1215-1221. doi: 10.1177/08927790251387343. Epub 2025 Oct 22.