Progressive Familial Intrahepatic Cholestasis Treatment with Maralixibat over an Extended Term – Phase III

MRX-503: An Extension Study to Evaluate the Long-term Safety and Efficacy of Maralixibat in the Treatment of Subjects with Progressive Familial Intrahepatic Cholestasis

Protocol Description

This multi-center research program evaluates the effectiveness, potential side effects, and how the body processes the drug maralixibat when used as a therapy for progressive familial intrahepatic cholestasis (PFIC) in children, adolescents and teens over an extended period of time. PFIC is a rare genetic condition in which cells in the liver cannot release bile, a fluid that helps the body digest food. As a result, bile builds up in the liver, leading to symptoms such as jaundice, itching, impaired growth, and delayed puberty.

Study Level: Phase III

Eligibility Criteria

This study (MRX-503) is open to patients who have PFIC and who participated in an earlier maralixibat study protocol (MRX-502). 
Males and Females: 1 to 18 years of age


The study drug will be given as an oral solution taken twice a day. Each day, participants or their caregivers will be required to complete study questionnaires using an electronic data logging device provided by the study team. Participants will receive examinations, including blood and urine sampling, and ultrasound imaging at specific intervals.
Visits: 16
Duration: 2 years

Status: Enrolling by Invitation

Source(s) of Support

Mirum Pharmaceuticals

Contact Information

For more information about the study or enrollment, please contact:
Clinical Research Nurse Coordinator Amanda Blasko, RN, BSN