Summary: This is a Phase 1/2, multinational, open-label, escalating-dose study to evaluate the safety and efficacy of an intravenous infusion of GNT0003 in patients with Crigler-Najjar aged ≥10 years and requiring phototherapy. Patients will received a single administration of GNT0003 and will be followed for safety and efficacy of approximately 60 months (5 years):~a follow-up of approximately 12 months (...