An implantable neuromodulation device the size of a nickel, named ‘eCoin’, is safe and effective for treating urge urinary incontinence (UUI) associated with overactive bladder (OAB), according to a paper in the Journal of Urology.

First-line therapy for OAB is usually pharmacological but many patients do not respond, so alternatives are needed. In a prospective study carried out at seven institutes in the USA and New Zealand, the eCoin device was implanted in the medial lower leg of patients in an office-based procedure under local anaesthetic, after which efficacy and safety were assessed. “It was noteworthy how easy the eCoin device was to implant both for the patient and physician,” comments corresponding author Scott MacDiarmid.

After the device was activated, electrical stimulation to the tibial nerve was delivered as a constant-current pulse (20 pulses per second; pulse width 0.2 ms) with the stimulation pulse amplitude (0.5–15 mA) adjusted to the highest comfortable level for the patient, for 30-minute stimulation sessions every 2 days for 12 weeks.

Across the seven sites, 46 participants were implanted with the device, with a mean age of 63.4 ± 11.5 years; 98% of study participants were female. Patients experienced a median of 4.2 episodes of UUI per day at the baseline point (range 1–14.0). The median number of episodes of UUI dropped to 1.7 (range 0–10.7) per day at 3 months and 1.5 (range 0–10.7) episodes per day at 6 months, a median 71% relative reduction in number of episodes at 12 weeks (P = 0.001). Notably, after 6 months of therapy, 31 of the 46 participants (67.4%) continued to respond, with 22 (47.8%) experiencing a reduction in UUI of >75% and 11 (23.9%) participants experiencing complete cessation of UUI. Patient-reported outcome measures also reflected these data, with an I-QOL change from baseline of nearly three times the minimally important difference for this measure, and 15/46 (33%) of patients feeling “very much better” according to the PGI-I questionnaire. No revision or removal was needed because of discomfort, pain, or infection at the implant or incision site.

MacDiarmid concludes: “We need to continue to offer therapies beyond medications that fail to reach the patient’s treatment goal in the majority of cases. eCoin is an exciting new therapy that, with FDA approval, will provide us with a safe and effective treatment tool for these refractory patients.”