*3.1.5.2 Efficacy and safety profile*

This first reported human phase 1 study enrolled 17 patients with a median BMI of 40.2 kg/m<sup>2</sup> who underwent the ACE procedure [34]. Adverse events involved gastric pain (n = 7), sore throat (n = 4), diarrhea (n = 4), nausea (n = 3), and

constipation (n = 4), but resolved with conservative treatment within 15 days after surgery. No SAE occurred. Patients demonstrated a median % EWL of 34.9% (IQR 17.8–46.6) in the first year. This phase 1 study showed that the ACE stapler is safe and effective in humans. The study was funded by Barosense until sufficient funds could no longer been raised and further research was discontinued. However, randomized controlled trials and long-term follow up are needed to determine its place in the treatment of obesity. With acquisition by Boston Scientific Group, follow-up research on the ACE procedure may be on the horizon in the near future.

## *3.1.6 The incisionless magnetic anastomosis system*

The incisionless magnetic anastomosis system (IMA) manufactured by GI Windows (Boston, MA) is a compression anastomosis technology used to create a dual-path enteral bypass in the small bowel with the use of octagon shaped selfassembling magnets.

## *3.1.6.1 Technique*

Under fluoroscopic guidance, self-assembling magnets are delivered in the proximal jejunum and ileum by simultaneous upper and lower endoscopy. After deployment and coupling due to the magnetic field, the tissue in between will be pressed against each other causing necrosis. The necrotized tissue induces remodeling of the surrounding tissue, leading to the formation of a jejunal-ileal anastomosis. After the anastomosis has been established, the coupled magnets will be expelled by the feces.
