Omega Gastric Bypass (150cm) Compared to the Roux-en-Y Gastric Bypass (YOMEGA-2 Multicentric Trial)

Randomized Controlled Non-inferiority Trial Evaluating the Safety and Efficacy of the Omega Gastric Bypass With 150 cm Biliopancreatic Loop Length Compared to the Roux-en-Y Gastric Bypass

Obesity with its consequences such as type 2 diabetes, high blood pressure, dyslipidemia, fatty liver disease, sleep apnea and cancers, remains a major healthcare problem worldwide. Bariatric surgery, combined with nutritional education and close monitoring, has been shown to be the most effective treatment for patients with morbid obesity resulting in significant and lasting weight loss and improvements in co-morbidities . With nearly 50000 procedures per year France ranks third in the world in terms of care for patients suffering from morbid (BMI ≥ 40 kg/m²) and severe (BMI 35-40 kg/m²) obesity.

In parallel with the significant increase in the number of patients operated on for obesity in the world, over the past two decades, significant development has been observed in the field of bariatric surgery with a decrease or even disappearance of some procedures and the appearance of others.

Performed for more than 40 years, the Roux-en-Y Gastric Bypass (RYGB) is a restrictive and malabsorptive procedure and currently is considered as gold standard procedure for the treatment of morbid obesity and its comorbidities. However, despite the good effectiveness (with an average Excess Weight Loss % (EWL%) of approximatively 70% at 2 years), RYGB is technically demanding procedure with learning curve requiring more than 100 cases and an overall complication rate ranging from 10% to 20% Introduced in 2001, one anastomosis gastric bypass (OAGB) is a modified gastric bypass that consists of a single gastrojejunal anastomosis between a long gastric pouch and a jejunal (biliopancreatic) omega loop. In Sept. 2019, taking into account the results from YOMEGA trial, the French High Authority for Health (Haute Autorité de Santé (HAS)) recommended to ban OAGB with 200 cm or longer BPL and urged to assess the efficacy and safety of OAGB with 150 cm BPL in a randomized controlled trial. Indeed, YOMEGA-2 trial is logical continuity of the YOMEGA trial.

The aim of this study is to assess weight loss efficiency and the nutritional safety of the OAGB-150 in comparison to a standard (RYGB).

The hypothesis of this study is that the OAGB with a 150 cm BPL could have the same efficacy on weight loss and nutritional complication rate in comparison to the RYGB at 2 years.

Inclusion Criteria:

• Patient aged from 18 to 65 years old
• Type III obesity (BMI ≥ 40 kg/m²), or Type II obesity BMI 35-40 kg/m2 associated with at least one co-morbidity which will be improved by surgery (high blood pressure, type 2 diabetes mellitus, obstructive sleep apnea, dyslipidemia, arthrosis)
• Patient who had benefited from an Upper GI Endoscopy with biopsies to look for Helicobacter pylori within 12 months before surgery
• Patient who has benefited from a multidisciplinary evaluation at least 6 months, with a favorable opinion for a gastric bypass
• Patient who understood and accepted the need for a long-term follow-up
• Patient who agreed to be included in the study and who signed the informed consent form
• Patient affiliated to a social security scheme
• For child-bearing aged women, efficient contraception

Exclusion Criteria:

• History of previous bariatric surgery
• History of chronic inflammatory bowel disease
• Presence of chronic diarrhea
• Presence of a severe and evolutive life threatening pathology
• Presence of dysplastic modifications of the gastric mucosa, chronic atrophic gastritis or history of gastric cancer
• Presence of an unhealed gastro-duodenal ulcer
• Presence of Helicobacter pylori resistant to medical treatment
• Presence of esophagitis
• Pregnancy or desire to be pregnant during the study
• Mentally unbalanced patients, under supervision or guardianship
• Patients who don't understand French and not able to give consent
• Patient included and followed in another interventional trial
• Unable to consent, under tutelage or curatorship, or judiciary safeguard
• Presence of type 1 diabetes