A Research Study to Evaluate Safety and Efficacy of DUR-928 in Subjects With Primary Sclerosing Cholangitis (PSC)

Inclusion Criteria:

• Verified diagnosis of primary sclerosing cholangitis (PSC) for at least 12 months,with or without inflammatory bowel disease (IBD).
• Serum alkaline phosphatase (ALP) ≥ 1.5 times ULN and with no >15% fluctuation in thepast 3 months.
• In subjects receiving treatment with ursodeoxycholic acid (UDCA), therapy must bestable for at least 3 months and at a dose not greater than 20 mg/kg/day.
• Subjects of childbearing potential must agree to use a medically acceptable method ofcontraceptive to prevent pregnancy in the subject and/or the partner for the durationof their participation in the trial up to 2 months after the last study drug dosing.

Exclusion Criteria:

• Presence of documented secondary sclerosing cholangitis or small duct PSC
• Bacterial cholangitis within 30 days prior to Screening
• Presence of percutaneous drain or endoscopic bile duct stent
• History of, or suspicion of cholangiocarcinoma.
• Prior liver transplantation, or currently listed for liver transplantation
• Presence of other concomitant liver diseases
• Moderate to Severe active IBD or flare in colitis activity within the last 3 months
• Any severe and/or untreated concomitant cardiovascular, renal, endocrine orpsychiatric disorder
• Any active malignant disease (within 3 years), other than non-melanomatous skin cancer
• Human immunodeficiency virus (HIV) infection
• Existing or intended pregnancy, or breast feeding
• Has received medication from another clinical trial within the past 30 days