Novel Implantable Tibial Neuromodulation System Shows Promising Results in Treatment of OAB

Objectives: This trial examines a novel miniature, battery-less, implantable tibial neuromodulation device (iTNM) (figure 1).

The design of this wirelessly powered implant supports current steering towards the nerve and results in improved energy transfer. A wearable device powers and controls the stimulation parameters. A Clinician Programmer is used to individually tailor stimulation parameters, prescribe Multiple Treatment Programs (MTP) if needed, and assess compliance with therapy.

This trial was conducted to evaluate the safety and efficacy of the iTNM for treating Urgency Urinary Incontinence (UUI) in women.

Methods: Women were enrolled in this prospective, single arm, open-label study. Inclusion criteria required at least 9 UUI episodes per 7-day diary. The study was conducted at 23 centers in the United States and Europe.

A minimally invasive surgical technique was developed to place the device subfascially, with direct visualization of the tibial NeuroVascular Bundle (NVB) with intra-operative testing used to optimize placement.

The implant was activated at ~4 weeks after implantation. Patients were instructed to perform treatments daily with the wearable device for 30-120 minutes.

Stimulation programs were individualized according to a predefined algorithm for non-responders or partial responders. Multiple Treatment Programs were set when needed to allow patients to switch between programs at home.

Efficacy endpoints were UUI episodes at 6 and 12 months compared to baseline. Safety endpoint was incidence of adverse events at 12 months post implantation.

Results: One hundred and fifty-one subjects, mean age 59.6 (SD: 12.1), have been successfully implanted. The subjects demonstrated mean baseline of 4.72 UUI/day (SD 3.0) and 10 voids/day (SD 3.2). At 6 and 12 months, 76.4% and 78.4% of participants were therapy responders in the ITT analysis set. In the completer set analysis at 12 months, 67% achieved ≥ 75% reduction in UUI episodes. Fifty percent were considered “dry” at 12 months (defined as 3 consecutive diary days without leaks). (Figure 2)

Compliance and patient satisfaction were both high at 91.6% and 95% respectively.

No Serious Adverse Events (SAEs) related to the device or the procedure were recorded throughout 12 months. Six patients (4.0%) experienced device related adverse events, and 10 patients (6.6%) experienced wound related AEs, classified as either mild or moderate.

Conclusions: The iTNM system showed high efficacy in reducing UUI episodes. Efficacy was durable with a growing proportion of responders throughout 12 months of follow-up. Patient-centric approach may have contributed to high patient compliance and satisfaction.

The open procedure and direct visualization of the NVB demonstrated a favorable safety profile with no device or procedure related SAEs and a low rate of AE’s.