Treatment begins in pivotal study of rechargeable sacral neuromodulation device for OAB

The first patient has been implanted with the InterStim Micro neurostimulator in the ELITE study, which is examining the rechargeable sacral neurostimulation (SNS) system in patients with overactive bladder (OAB).¹

The study is examining the InterStim Micro in patients across all 4 symptoms for which the SNS device is indicated: urinary urge incontinence, urinary frequency, non-obstructive urinary retention, and fecal incontinence.

Keith Xavier, MD

Millions of adults in the United States suffer from bladder and bowel disorders," Keith Xavier, MD, the physician who implanted the device in a patient with OAB, stated in a press release. "Through the ELITE study, our goal is to further validate existing data that sacral neurostimulation is a safe, long-term solution for patients who are limited professionally, personally, and socially by their condition," added Xavier, a founding partner of Urology Partners of North Texas.

SNM works by sending electrical impulses to the sacral nerves, which then modulates nerve activity to foster improved brain-bladder communication. The benefits of the InterStim Micro listed by its manufacturer, Medtronic, include that it is half the size of the other available rechargeable SNM device on the market, and it can fully recharge in under 1 hour.

The target enrollment of the ELITE trial is 160 patients and the study is being conducted at 40 locations across the United States, Canada, and Australia. Patient follow-up will go on for 2 years, with key study end points being patient-reported outcomes, disease-specific quality-of-life (QoL) questionnaires, and symptom diaries.

In August 2020, the FDA approved the InterStim Micro neurostimulator, along with the InterStim SureScan MRI leads, for the treatment of patients with bladder and bowl control conditions.

Long-term SNM results

Five-year follow-up data from a prospective, multicenter study were previously published showing the efficacy and QoL benefits of SNM (InterStim Micro) in patients with bothersome symptoms of overactive bladder, including urinary urge incontinence and/or urgency-frequency. Successful treatment was defined as a “urinary urge incontinence or urgency-frequency response of 50% or greater improvement in average leaks or voids per day, or return to normal voiding, defined as fewer than 8 voids per day.”² The investigators measured QoL using the International Consultation on Incontinence Modular Questionnaire (ICIQ-OABqol).

Overall, 272 patients had the device implanted. The average age was 57 years and 91% of patients were women. Among the 202 patients with urinary urge incontinence, the mean number of leaks per day at baseline was 3.1. Among the 189 patients with urgency-frequency, the mean number of voids per day at baseline was 12.6.

Modified completers analysis showed a 5-year therapeutic success rate of 67% and completers analysis showed a success rate of 82% . The mean reduction from baseline among patients with urinary urge incontinence was 2 leaks per day, and the mean reduction from baseline among patients with urgency-frequency was 5.4 voids per day.

There was a significant improvement in QoL in all ICIQ-OABqol measures (P <.0001). All 272 patients were evaluable for safety. The most frequently occurring adverse events related to the device were an undesirable change in stimulation (22%), implant site pain (15%), and therapeutic product ineffectiveness (13%).

References

1. Medtronic Announces First Patient Implanted in ELITE Study of InterStim™ Micro. Posted October 6, 2020. Accessed October 6, 2020. https://prn.to/2F4ygZA.

2. Siegel S, Noblett K, Mangel J, et al. Five-Year follow-up results of a prospective, multicenter study of patients with overactive bladder treated with sacral neuromodulation. J Urol. 2018;199(1):229-236. doi: 10.1016/j.juro.2017.07.010