Medtronic Tibial Stim Approval to Impact OAB Market

by Victor Pikov, contributing editor

September 2025 issue, BioElectRx Business Report

According to our 2024 Market Report on Bioelectronic Medicine, OAB is the leading segment in the bioelectronic medicine market and is poised for continued growth in coming years due to an aging population, chronic stress, and growing patient awareness of neuromodulation therapies. In the OAB market, implantable SNS devices hold the lion’s share, while wearable devices for percutaneous and transcutaneous tibial nerve stimulation remain on the margins, as we reported in our December 2024 issue.

This month, the OAB market became more crowded following Medtronic’s FDA PMA approval for its implantable TNS device Altaviva. The approval is based on results from Medtronic’s single-arm TITAN 2 pivotal clinical study, in which 188 OAB patients with urgency symptoms were treated with TNS for 6 months. The PMA approval took 17 months, in contrast to the speedier nine-month approval for Neuspera’s iSNM device, as reported in our June 2025 issue.

Medtronic becomes the third US player in implantable TNS, following Valencia Technologies with their eCoin device (PMA approval in 2022) and BlueWind Medical with their Revi device (510(k) de novo clearance in 2023). When comparing TNS efficacy (defined as 50% or greater reduction in urgency symptoms) Altaviva appears less efficacious with 61% efficacy in its pivotal clinical study compared with 70-78% efficacy for eCoin and 78% efficacy for Revi.

From an engineering standpoint, one key difference lies in device volumes: Altaviva is significantly larger (at 7.4 cc) than either eCoin (at 1.4 cc) or Revi (at 0.25 cc). Another key difference between these devices is in batteries: Altaviva uses a rechargeable battery that needs recharging once or twice per year, eCoin uses a 75 mAh primary battery with a typical lifespan of three years, and Revi has no battery, instead requiring a calf-attached charger during each therapy session.

From both efficacy and volume standpoints, Altaviva seems slightly inferior to existing TNS devices. However, both Altaviva and eCoin offer better therapy compliance than Revi due to their long-lasting batteries.

Next, let’s compare implantable TNS and SNS therapies, as both implantable therapy types are approved for treating the same subset of OAB patients with urgency symptoms, representing more than 80% of all patients. Urgency is the most bothersome of OAB symptoms, so these patients are rather compelled (urged) to undergo implantation surgery to achieve relief from this symptom.

Implantable SNS devices on the U.S. market include Medtronic’s InterStim devices and Boston Scientific’s Axonics devices with regular-sized IPGs and the recently approved Neuspera’s iSNM lead without the IPG or battery.

When comparing efficacy of SNS devices, iSNM excelled in its pivotal study with 96% efficacy compared with 88- to 93% efficacy for Axonics and 79% efficacy for InterStim.

When considering implantation procedures for TNS and SNS therapies, TNS devices offer advantages, as they do not require sedation or fluoroscopy, in contrast to SNS devices, which require both. Mr. Surek, CEO of Valencia Technologies, commented to our newsletter that “SNS devices penetrated 0.2% of the market. There are many reasons why, but mostly because no one wants a battery and leads implanted in their spine and back. This market is not growing, also Medtronic and Boston Scientific only focus on the SNS implanters and that is about 2k doctors. The other 6-8k surgeons have said “no thank you” to SNS because of all the after-implant service that takes place at the office where implant was performed. eCoin democratizes the OAB neuromodulation implants because of ease of implantation and absence of after-implant service. We implant it, forget it, and see you 3+ years from now for a new implant – we unclog the practice. 91% of our patients get 2 or less programming visits over 3 years.”

Stimulation regimens for implantable TNS and SNS therapies differ significantly. TNS devices deliver stimulation for 30-60 min every one to four days, while SNS devices deliver stimulation continuously for 24 hours. As TNS devices are placed at a distance of 3-5 mm from the posterior branch of the tibial nerve, they require a current level of about 6 mA for nerve activation with potential current spread to other nerves. SNS devices are placed about 1 mm from the sacral nerve and typically require only 2-3 mA for nerve activation.

Considering these differences, it might be appropriate to position existing implantable TNS devices as a second-line therapy for OAB patients due to their ease of implantation and highly reduced need for after-implant programming, while implantable SNS devices serve as a third-line therapy based on their superior efficacy and long-term compliance that comes at the price of higher invasiveness and associated surgical costs.

The OAB neuromodulation market in the U.S. has become quite crowded with six implantable TNS and SNS devices, but the shakeup will continue in the years ahead, as several more startups race to the finish line. These include Coloplast with an implantable TNS device, Uro Medical with an implantable SNS device, Amber Therapeutics with an implantable pudendal nerve stimulation device, Juniper Biomedical with an implantable pelvic nerve stimulation device, and InnoCon Medical with a partially-implantable dorsal genital nerve stimulation device.

While Medtronic’s PMA-approved Altaviva device adds another option to the growing OAB neuromodulation market, its larger size and lower efficacy compared to competitors suggest the TNS segment may best serve as a more affordable and less invasive second-line therapy before patients consider the more effective but also more invasive SNS devices.