Clinical and technical evidence

A literature search was carried out for this briefing in accordance with the interim process and methods statement. This briefing includes the most relevant or best available published evidence relating to the clinical effectiveness of the technology. Further information about how the evidence for this briefing was selected is available on request by contacting

Published evidence

Three studies are summarised in this briefing. They include 2 prospective, single-arm, before-and-after observational studies and a case series, including a total of 62 people with faecal incontinence.

The clinical evidence and its strengths and limitations is summarised in the overall assessment of the evidence.

Overall assessment of the evidence

Overall, the available evidence suggests that using Axonics SNM system can help reduce episodes of faecal incontinence and improve quality of life. It also suggests that the system is straightforward to charge and that most people are satisfied with their therapy. No unanticipated or serious device-related events were reported in any of the studies.

The evidence base for using Axonics SNM system in the treatment of faecal incontinence is limited. Available evidence comes from a total of 62 people in 2 single-armed studies (1 of which was not primarily designed to evaluate the effectiveness in the treatment of faecal incontinence) and a small case series. There is a lack of randomised trials and a lack of direct comparison between Axonics SNM system and the standard care alternative.

Clinical effectiveness in treating faecal incontinence has not been shown for longer than 2 years. An extended follow up would be desirable, given the intended duration of implant with the rechargeable SNM device.

Only 1 of the studies was exclusively done in the UK (Dudding 2017). This was a small, single-centre case series involving 5 people. Data from this study were published in a conference abstract only and could not be fully assessed for statistical or clinical significance. The ARTISAN‑SNM study included 1 UK centre but the proportion of people with faecal incontinence from this UK study site was not reported. The remaining study (Jottard et al. 2020) was done in Belgium which may limit generalisability to the NHS. This study reports on a single-nonstaged procedure which differs to current clinical practice that recommends an external trial phase is done before having a permanent implant.

Jottard et al. (2020)

Intervention and comparator

Axonics SNM System, no comparator.

Key outcomes

Most people (n=13, 87%) had a 50% or higher reduction in faecal incontinence episodes at 4 weeks (as documented in patient bowel diaries). Using Axonics SNM system was associated with a 75% reduction in weekly faecal incontinence episodes at 4 weeks and a 79% reduction at 6 months (from a median of 8 at baseline to 1.5 at 4 weeks and at 6 months, p=0.001 for both time points). Twelve of the 13 people (92%, per protocol) who had a 50% or higher reduction in faecal incontinence episodes at 4 weeks, also had a 50% or higher reduction in faecal incontinence episodes at 6 months. Health change and quality of life, as measured by the symptom-related quality of life survey (SF‑36), improved significantly at 6 months (p=0.016). There were no unanticipated device- or procedure-related adverse events. Mean time to recharge the system was 37 minutes (plus or minus 3 minutes) once or twice per week. All patients were moderately or very satisfied with the system and its effect.

Strengths and limitations

Study involves a small number of people and has a short-term follow up of up to 6 months. The study reports on a single-nonstaged procedure and may not be generalisable to current clinical practice which advises that an external trial phase is done before having a permanent implant.

Pezzella et al. (2021), Benson et al. (2020) and McCrery et al. (2020)

Study size, design and location

Prospective, multicentre, before-and-after study (ARTISAN-SNM study) of 129 people with urinary urgency incontinence (UUI) in whom symptoms were not controlled with or who could not tolerate more conservative treatments. Study done in the US (14 centres), Belgium (1 centre), the Netherlands (2 centres), France (1 centre) and the UK (1 centre).

Of the 129 people in the study, 33% (n=42) had faecal incontinence at baseline (a score of 6 or greater on the Cleveland Clinic Florida-Faecal Incontinence Score [CCF‑FIS]. Six‑month data from this trial is reported in McCrery et al. (2020), 1‑year data in Benson et al. (2020) and 2‑year data in Pezzella et al. (2021).

Intervention and comparator

Axonics SNM System, no comparator.

Key outcomes

At 6 months, the average CCF‑FIS score in the 41 people with faecal incontinence available at follow up was 4.6 (plus or minus 0.3) compared with 9.3 (plus or minus 0.3) at baseline. For 73% of these people (n=30) the CCF‑FIS score was less than 6 at 6 months. At 1 year, the average CCF‑FIS score in all people with faecal incontinence reduced from 9.3 (plus or minus 0.5) at baseline to 3.9 (plus or minus 0.6) at 1 year (p<0.0001). At 2 years, CCF‑FIS was statistically significantly reduced to 3.7 (plus or minus 0.5; p value<0.001). All people in the study were able to recharge their device during the 2‑year study. There were no serious device-related adverse events reported.

Strengths and limitations

Multicentre study which included 1 UK centre. This was a non-randomised study, with no comparator or placebo arm. It was not primarily designed to evaluate the efficacy of Axonics SNM system in people with faecal incontinence.

Dudding (2017)

Intervention and comparator(s)

Axonics SNM System, no comparator.

Key outcomes

All patients reported a good response to therapy at 1 month after implantation, defined as over 75% reduction in episodes of faecal incontinence. The St Mark's continence score was reduced from a mean of 18 at baseline to 5 at 1 month. At 3 months, 4 out of 5 patients continued to benefit from therapy. Recharging was done at a median of 7 days (range: 7 to 10 days) with no patient needing greater than 60 minutes per charging session. No patient reported any problems with recharging the device.

Strengths and limitations

This is a UK NHS study. It is a single-site case series involving a small sample of people with no comparator group. The statistical and clinical significance of efficacy outcomes were not reported, and no baseline demographics were available.


The company proposes that the environmental impact of the rechargeable device would be reduced because of less frequent replacement of neurostimulator devices. There is no published evidence supporting this assumption.

Recent and ongoing studies

No ongoing or in-development trials evaluating the use of the technology in the treatment of faecal incontinence were identified.