Evaluation of an Oral Microbiota-based Therapeutic as a Treatment Option for PSC

Inclusion Criteria: * Ages 18-76 * Serum total bilirubin at screening ≤ 2x the upper limit of normal * Absence of biliary obstruction and malignancy by ultrasound or equivalent imaging within 6 months of study entry * Anticipated maintenance of current medication regimen through the treatment period (UDCA, azathioprine, corticosteroid, methotrexate, 5-ASA, biologic therapy and/or probiotic) * 3-month washout period of obeticholic acid or other experimental therapies for PSC * Stated willingness to comply with all study procedures and availability for the duration of trial to follow-up by telephone, in-person, email, and/or video visits or correspondence. * Informed consent Exclusion Criteria: * Antibiotic therapy (except vancomycin) within 3 months or anticipated antibiotic use in the course of the MTT treatment * Presence of complications of advanced PSC, such as hepatic encephalopathy, ascites, history of esophageal varices, portal hypertension, hepato-renal syndrome, portopulmonary syndrome, and hepato-pulmonary syndrome * Evidence for viral hepatitis (history of Hepatitis C is eligible with undetectable HCV RNA); HIV/AIDS * Metabolic or inherited liver disease (e.g., Wilson's, hemochromatosis, alpha-1-antitrypsin deficiency) * Another disease involving bile ducts (e.g., primary biliary cholangitis, IgG4-related cholangitis, secondary sclerosing cholangitis) * Evidence of cirrhosis on the last magnetic resonance cholangiopancreatography (within 6 months) * Pregnancy or attempting to become pregnant or breastfeeding. * History of liver transplantation, anticipated need for liver transplantation within 12- months from randomization, or a Model of End Stage Liver Disease (MELD) score of ≥15 * Active malignancy * Active alcohol overuse (\>4 drinks per day for men, and \>2 drinks per day for women) * Moderate-to-severe renal impairment with a calculated creatinine clearance of \< 45 mL/min * Neutropenia (an absolute neutrophil count \< 0.5 x 109 cells/L) * History of allergic reaction to vancomycin * History of allergic reaction to amoxicillin or other beta-lactam antibiotics * Any other conditions or abnormalities that, in the opinion of the investigator, may compromise the safety of the subject or interfere with the subject participating in or completing the study * Total colectomy