Study of the Effects of Obeticholic Acid on Farnesoid X Receptor Expression in Jejunum and on Gut Microbiota in Morbidly Obese Patients and Healthy Volunteers

OCAPUSH (EudraCT 2014-002313-33) is a double-blind placebo-controlled parallel-arms study of the effects of obeticholic acid on farnesoid X receptor expression in jejunum and on gut microbiota in morbidly obese patients and healthy volunteers. Obeticholic acid (OCA, 6-ethyl-chenodeoxycholic acid, INT-747) is a semi-synthetic derivative of the major human bile acid chenodeoxycholic acid and will be administered orally at a dose of 25 mg/day during three weeks to 20 morbidly obese patients awaiting Roux-en-Y gastric bypass and to 20 healthy volunteers. On the days before the first and after the last dose faeces and blood are sampled for the analyses of bile acids and the gut microbiota. On the day after the last dose a push-enteroscopy is performed in conscious sedation for biopsy taking in the jejunum.These procedures are repeated 6 month after surgery in the morbid obese patients. Inclusion criteria are male or female gender, 20-65 years of age and morbid obesity (BMI >35 kg/m2) eligible for bariatric surgery. Exclusion criteria are liver diseases other that fatty liver disease, other significant morbidity, medications known to interact with OCA, pregnancy, uncertainty about safe and reliable contraception, and problems to understand or adhere to the protocol. The primary objectives of this pharmacodynamic trial are the study of the effect of OCA on the expression of FXR in the jejunum and small intestinal permeability, and on fecal bile acids and gut microbiota. The secondary objectives are the study of the effects of OCA on the genome-wide FXR DNA binding sites (cistromics) with the global gene expression profile (transcriptomics) in human jejunum.