Safety, Pharmacokinetics, Pharmacodynamics, and Efficacy of Migalastat in Pediatric Subjects (Aged 12 to <18 Years)

This was a Phase 3b, 2-stage, open-label, uncontrolled, multicenter study to evaluate the safety, PK, PD, and efficacy of migalastat treatment in pediatric participants 12 to \<18 years of age and weighing ≥ 45 kilograms (99 pounds) with Fabry disease and amenable GLA variants. Participants must have been naïve to enzyme replacement therapy (ERT) or have stopped ERT at least 14 days at the time of screening. Stage 1 was a treatment period of approximately 1 month (4 weeks); Stage 2 was a treatment period of 11 months and a 30-day (untreated) safety follow-up period. There was no break in treatment between Stages 1 and 2. Prior to Stage 1, there was a screening period lasting at least 14 days and up to 30 days (or more, if GLA genotyping was required). Stages 1 and 2 together consisted of a 12-month treatment period, and a 30-day safety follow-up period, for a total of approximately 13 months. Upon study completion, participants had the option to enroll in a long-term extension study conducted under a separate protocol (NCT04049760). Participants were randomly assigned 1:1:1 to 1 of 3 PK sampling groups using interactive response technology (IRT). Four blood samples for the determination of migalastat concentrations in plasma were collected during Stage 1 study drug administration, and 1 PK (trough) sample was collected at Month 6 and again at Month 12.