An Extension Study of Maralixibat in Patients With Progressive Familial Intrahepatic Cholestasis (PFIC)

Study Overview
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Brief Summary
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The primary objective of this open label extension study is to evaluate the long-term safety and tolerability of maralixibat.

Detailed Description
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The study will be conducted at multiple sites in North America, Europe, Asia, and South America.

Official Title
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An Open-label Extension Study to Evaluate the Long-term Safety and Efficacy of Maralixibat in the Treatment of Subjects With Progressive Familial Intrahepatic Cholestasis (PFIC)

Conditions
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Progressive Familial Intrahepatic Cholestasis (PFIC)

Intervention / Treatment
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* Drug: Maralixibat


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Provide informed consent and assent (as applicable) per Institutional Review Board/Ethics Committee (IRB/EC) Completion of study MRX-502 Exclusion Criteria: Any female who is pregnant or lactating or who is planning to become pregnant Administration of prohibited medication between the MRX-502 EOT visit and the MRX 503 Baseline Visit (Day 0) History of non-compliance in study MRX-502, non-adherence to medical regimens, unreliability, mental instability or incompetence that could compromise the validity of informed consent or lead to non-adherence with the study protocol based on Investigator judgment Experienced an adverse event (AE) or serious adverse event (SAE) related to maralixibat during the MRX-502 study that led to permanent discontinuation of the subject from maralixibat Any other conditions or laboratory abnormalities that, in the opinion of the Investigator or Sponsor Medical Monitor, may compromise the safety of the subject, or interfere with the subject participating in or completing the study

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Maralixibat<br>All subjects will receive Maralixibat oral solution | Drug: Maralixibat<br>* All subjects will receive Maralixibat oral solution (up to 600 microgram per kilogram [mcg/kg]) twice daily<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Treatment Emergent Adverse Events (TEAEs) during the study |  | From baseline through time of interim analysis, up to 120 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from maralixibat baseline over the course of the study in the weekly average morning ItchRO(Obs)™ (Itch Reported Outcome) severity score |  | From baseline through study completion, up to approximately 4 years | 
| Maintenance of treatment effect based on the average morning ItchRO(Obs)™ severity scores over the time |  | From baseline through study completion, up to approximately 4 years | 
| Mean change from baseline over time in serum bile acid (sBA) levels |  | From baseline through study completion, up to approximately 4 years | 
| Change from maralixibat baseline over the course of the study in the weekly average morning ItchRO(Obs)™ (Itch Reported Outcome) frequency score |  | From baseline through study completion, up to approximately 4 years | 
| Mean change from baseline over time in height and weight z-scores |  | From baseline through study completion, up to approximately 4 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cholestasis, Maralixibat, Mutation, PFIC, PFIC2, Bile Duct Diseases, Liver Diseases, Biliary Tract Diseases, Digestive System Diseases, Pediatric