Prospective multicentre randomised trial comparing the efficacy and safety of single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) versus Roux-en-Y gastric bypass (RYGB): SADISLEEVE study protocol

Abstract

Introduction: Despite the non-negligible weight loss failure rate at midterm, Roux-en-Y gastric bypass (RYGB) remains the reference procedure in the treatment of morbid obesity with metabolic comorbidities. A recently emerged procedure, the single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S), could be more effective on weight loss with similar morbidity and lower weight loss failure rate than RYGB. We propose the first randomised, open, multicentre superiority trial comparing the SADI-S to RYGB (SADISLEEVE).

Methods and analysis: The main objective is to demonstrate the superiority at 2 years after surgery of the SADI-S compared with RYGB in term of excess weight loss percentage. The secondary objectives are the evaluation of nutritional status, metabolic outcomes, overall complication rates and quality of life, within 2 years after surgery. Key inclusion criteria are obese patients with body mass index (BMI) ≥40 kg/m² or ≥35 kg/m² with at least one comorbid condition and candidate to a first bariatric procedure or after failure of sleeve gastrectomy. Patients randomised by minimisation in two arms, based on centre, surgery as a revisional procedure, presence of type 2 diabetes and BMI >50 kg/m² will be included over 2 years.A sample size of 166 patients in each group will have a power of 90% to detect a probability of 0.603 that excess weight loss in the RYGB arm is less than excess weight loss in the SADI-S arm with a 5% two-sided significance level. With a drop-out rate of 10%, it will be necessary to include 183 patients per group.

Ethics and dissemination: The study was approved by Institutional Review Board of Centre Hospitalier Universitaire Morvan (CPP1089-HPS1). Study was also approved by the French national agency for drug safety (2018061500148). Results will be reported in peer-reviewed scientific journals.

Trial registration number: NCT03610256.

Keywords: clinical trials; nutrition & dietetics; surgery.

Figure 1

Roux-en-Y gastric bypass.

Figure 2

Single anastomosis duodeno–ileal bypass with sleeve gastrectomy.

Figure 3

Participant timeline diagram. BMI, body mass index; %EBWL, excess body weight loss percentage; %EWL, excess weight loss percentage; HbA1c, glycated haemoglobin; HDL, high-density lipoproteins; LDL, low-density lipoproteins; GIQLI, Gastrointestinal Quality of Life Index; RYGB, Roux-en-Y gastric bypass; SADI-S, single anastomosis duodeno–ileal bypass with sleeve gastrectomy; SF, short form; SG, sleeve gastrectomy; TG, triglycerides.

Figure 4

Theorical and real inclusions curves. The blue curve shows the rate of expected hypothetical inclusions needed to complete recruitment on time (n=366). The red curve shows the real number of inclusions between October 2018 and January 2020 (n=178).