Study to Evaluate EP547 in Subjects With Cholestatic Pruritus Due to Primary Biliary Cholangitis or Primary Sclerosing Cholangitis

Inclusion Criteria: * Age 18 to 80 years * Documented primary biliary cholangitis (PBC) or primary sclerosing cholangitis (PSC) * Presence of consistent moderate to severe pruritus * Use of anti-pruritic and anti-cholestatic (including UDCA and obeticholic acid) medication allowed if meeting additional criteria * Individuals with concomitant inflammatory bowel disease must meet additional relevant criteria Exclusion Criteria: * Pruritus associated with an etiology other than PBC or PSC * Prior or planned liver transplantation * Evidence of compensated or decompensated cirrhosis * Alternative causes of liver disease * Presence of documented secondary sclerosing cholangitis * Current evidence of clinically significant high-grade strictures or presence of biliary stent * History of significant small bowel resection or short bowel syndrome * Has exclusionary laboratory or biochemical results at Screening