A First-In-Human Feasibility Study of a New Implantable Tibial Nerve Stimulator for Overactive Bladder Syndrome

Abstract

Objectives: This study aimed to evaluate the preliminary feasibility and safety of a new implantable tibial nerve stimulator device in patients with overactive bladder (OAB).

Materials and methods: Ten patients with OAB in whom conservative treatments had failed participated in the study. All patients received daily stimulation therapy for two weeks and weekly stimulation therapy for 13 weeks, at the lowest electrical output amplitude at which paresthesia or motor response occurred. OAB symptoms (three-day bladder diary), quality-of-life scores (OAB-questionnaire Short Form), and patient global response (GRA) were assessed at each follow-up visit.

Results: Among the patients enrolled (mean age 68 years), seven were OAB-wet and three OAB-dry. After 13 weeks of therapy delivery, a reduction in the number of daily voids during waking hours (8.5 ± 2.5 to 6.3 ± 1.9; p = 0.016), incontinence episodes (2.5 ± 1.8 to 0.3 ± 0.5; p < 0.001), and the daily voids associated with urgency (7.6 ± 3.1 to 3.0 ± 3.1; p < 0.001) was reported. Eight of the ten subjects were classified as responders for ≥one OAB component, with one patient reporting worsened symptoms of urgency (+6%). All ten patients reported global improvement in symptoms on the GRA with a median score of 6. Improvements in OAB severity and health-related quality-of-life scores were noted from pre- to posttreatment across participants (p < 0.001). No serious adverse effects were noted.

Conclusion: This first-in-human pilot study allowed for capture of preliminary safety and effectiveness information on a new implantable tibial nerve stimulator device in the population of interest to adequately power a larger, pivotal randomized study.

Clinical trial registration: The Clinicaltrials.gov registration number for the study is NCT04115228.

Keywords: Feasibility; overactive bladder; tibial nerve; urgency urinary incontinence.