Treatment of UUI by SNM with an implantable pulse generator (IPG) and lead, with continuous 24/7 stimulation, has been standard of care for 20+ years.  Neuspera’s battery-less ultra-miniaturized-IPG/lead (0.12cc), implanted in a single procedure, is wirelessly powered via an external device for short daily stimulation durations. If efficacy is similar to traditional devices, the studied device can potentially reduce infection risk, complications and costs associated with traditional systems. We report initial results of the SANS-UUI study related to objective improvements and quality of life.

The multi-center, open-label trial included subjects with ≥6-month history of UUI and ≥4 UUI events on a 72-hour voiding diary.  Subjects completed a 21-day trial period with 2-hours of daily stimulation. Subjects with <50% UUI reduction at 21 days increased stimulation to 4-hours for 14 days. All responders (≥50% UUI reduction) at end of trial (21 or 35 days) continued into the follow-up period. The ICIQ-OAB was collected at baseline and at the Month 3 visit. For the ICIQ-OAB, a 10-point change in the score from baseline represents a clinically meaningful improvement in health-related quality of life (HRQL).

All 34 implanted subjects (94% women, mean age 62 yrs) completed trialing and ≥1-month follow-up, 33 subjects at 2 hrs and 1 at 4 hrs daily stimulation. All 34 subjects continue in the trial.  Responder rate was significantly greater than 50% at end of trial, 1- and 3-months, Table 1. Reductions in baseline UUI (4.1 ± 2.0, mean ± SD) to end-of-trial, 1-, and 3-month visits were statistically significant (Table 1), and 29% of subjects were dry at 3 months. Subjects stimulated 2.1 ± 0.6 hrs daily (mean ± SD) from implant to 3 months.

Five subjects had <50% response at 1-month. All were responders at 3-months. There were 24 device / procedure related AEs in 11 subjects. Four surgical revisions occurred: 2 lead dislodgements and 2 lead fractures. All 4 subjects restarted the trial phase, are included in Table 1 and were responders at last follow-up. One additional device fracture was reported in a subject with a previous fracture and revision with shorter implant model is pending. 

Seventeen subjects had completed the Month 3 visit at the time of this report, and 100% (17/17) of them completed the measure; one subject did not complete the Concern subscale. The overall total score shows a clinically and statistically significant improvement in the ICIQ-OAB at Month 3 from baseline, with a mean increase of 37.6 ± 21.2 (P<0.0001). Clinically and statistically significant improvements at Month 3 from baseline were also seen for all the subscores: Coping (45.7 ± 22.9, P<0.0001), Concern (38.9 ± 24.6, P<0.0001), Sleep (30.1 ± 27.9, P=0.0004), and Social (28.9 ± 18.8, P<0.0001).

Using the Neuspera ultra-miniaturized SNM system 2 hrs / day is safe and effective with 85% and 94% of subjects with clinically and statistically significant improvements in UUI at 1 and 3 months, respectively.  This therapy also demonstrated a clinically and statistically significant improvement in Overall ICIQ-OABqol and each of its sub-component at 3 months.

Short-term follow-up demonstrates the successful use of Neuspera’s ultra- miniaturized SNM system to treat patients with UUI. As this is intended as a first phase of larger trial, more subjects and longer-term outcomes are still needed to confirm its safety and efficacy.