Tibial neurostimulation system demonstrates safety and efficacy in urge urinary incontinence

The BlueWind RENOVA iStim system demonstrated favorable safety and statistically significant efficacy for treating urge urinary incontinence (UUI) in women, according to a study presented at the 2023 American Urological Association Annual Meeting in Chicago, Illinois.

In the poster presented at the meeting, the device is described as a “novel miniature, leadless, battery-less, sub-fascially implantable tibial neuromodulation system.  The implant is wirelessly powered and modulated by an external wearable unit.”  A clinician programmer is utilized to individually tailor stimulation parameters such as frequency, pulse width amplitude, and polarity.  Investigators conducted an individual device exemption pivotal trial (G200013) to evaluate the device’s safety and efficacy.

The investigators conducted a prospective, single-arm, open-label study, known as OASIS, of 151 women with UUI who were enrolled in 23 centers in the US and Europe.  Patients had a mean 4.8 UUI episodes per day at implantation.  Patients had to have at least 9 UUI episodes over a 7-day diary.  Device activation occurred approximately 4 weeks after implantation, with patients performing daily stimulation treatments at home twice daily for approximately 30 minutes each session.  The investigators collected voiding diaries, quality of life, and patient satisfaction questionnaires at 6 and 12 months after device activation. T he primary end points included safety, defined as adverse events (AEs) at 12 months, and efficacy, defined as at least a 50% reduction in UUI episodes compared with baseline at 6 months.

The Investigators reported that 76.4% of patients experienced at least a 50% reduction in incontinence episodes at 6 months, and 78.4% at 12 months.  In addition, 83.6% of patients at 6 months and 84.6% of patients at 12 months experienced at least a 10-point improvement (minimal important difference) in health-related quality of life (< .0001).  Seventy-four percent (74%) of patients at 6 months and 80.1% of patients at 12 months experienced an improvement in urgency episodes and voids (< .0001), and 88.0% of patients at 12 months experienced at least a 50% reduction in UUI or large-volume UUI episodes.

At 12 months, 91.6% of patients were compliant with the system, and 95% of patients reported being satisfied with the treatment.  Also at 12 months, half of patients were dry on 3 consecutive days of voiding diary.

“Tailored treatment parameters through reprogramming, together with the patient-centric approach, facilitate and improve responder rate over time,” the authors wrote in their poster.

First author John Heesakkers, MD, PhD, head of urology at the Maastricht UMC, the Netherlands, reported that there was no incidence of serious AEs related to the device or the procedure.  A total of 16 patients (10.6%) experienced procedure/wound-related AEs, and 6 patients (4.0%) experienced device-related AEs.  “We looked at safety issues within 12 months after the implantation, and they were minor—some pain problems, some wound-healing problems, but no serious adverse events,” Heesakkers told Urology Times®.

The investigators also reported that no surgical reinterventions were required; they pointed out in their poster that the device has no implantable batteries that need to be replaced, no leads that could break, and no migration as the implant is anchored to the fascia.  Asked what impressed him most about the study, Heesakkers said, “What impressed me the most is the implant because it is very small.  It is located in a position that is easy to access.  It is easy to do also for people that are not very familiar with ankle anatomy.”

REFERENCE:  Urology Times; 30 APR 2023; Benjamin P. Saylor