BACKGROUND & STUDY AIMS: Prospective study of efficacy and safety of Motorized Spiral Enteroscopy (MSE) to perform biliary endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy at 5 European centers. PATIENTS & METHODS: Consecutive patients with biliary indications for enteroscopy-assisted ERCP. Objectives were technical success, adverse event rate and patient radiation exposure. RESULTS: 89 patients were enrolled, 1 pancreatic indication excluded, all with variations of Billroth II reconstruction (29.5%) or Roux-en-Y reconstruction (70.5%), either with naive papilla (39%) or hepaticojejunostomy (61%). Main indications were anastomotic stricture treatment and/or biliary stone removal. Enteroscopy to reach the bile duct was possible in 65/88 patients (74%), bile duct cannulation in 54/88 (61%) and therapeutic ERCP was technically successful in 48/88 (54%). In Billroth II variations technical success was achieved in 13/26 (50%) compared to 35/62 (57%, p=0.5792 Chi square) in Roux-en-Y reconstructions (including bariatric gastric bypass). ERCP with intact papilla was successful in 17/34 (50%) compared to 31/54 (57%, p=0.4968 Chi square) in hepaticojejunostomy. In July 2023 the study was prematurely terminated since MSE was withdrawn by the manufacturer because of safety issues. Overall, in 12/88 (14%) patients adverse events (AE) were recorded and 6 (7%) were considered serious. Only 1 SAE was attributable to MSE enteroscopy: perforation of the proximal oesophagus during enteroscope insertion. CONCLUSIONS: This prospective multicenter study was prematurely discontinued due to withdrawal of the MSE by the manufacturer because of safety issues. Technical success of MSE-assisted biliary ERCP in different types of surgically altered anatomy was 54%, which was lower than anticipated. There was one oesophageal perforation attributable to the use of MSE. (clinicaltrials.gov: NCT05129449)