Long-Term Low-Intervention SafEty and Clinical Outcomes Clinical Study of LivmArli® in Patients With Alagille Syndrome in the European Union (LEAP-EU)

Inclusion Criteria: * Informed consent and assent (as applicable) * ≥2 months of age at Day 1 * A clinically and/or genetically confirmed ALGS diagnosis with pruritus secondary to chronic cholestasis * For the primary cohort, prescribed Livmarli at time of study entry * For the supplemental cohort, prescribed Livmarli prior to study entry Exclusion Criteria: * History of Liver Transplant * Any contraindications against Livmarli (as per SmPC) * Any condition or abnormality that, in the opinion of the investigator, may interfere with the participation in or completion of the study * Received an investigational drug within 30 days before the first dose of Livmarli (Participation in previous maralixibat studies or expanded-access programs is acceptable.) * Baseline data before start of treatment of Livmarli are unavailable (\<2 values before treatment) for key safety (LFTs, FSV laboratory results) and key efficacy (sBA, pruritus) parameter