Population Pharmacokinetics of Oral Migalastat in Adolescents and Adults With and Without Renal Impairment.

Migalastat is approved for the treatment of Fabry disease (FD) with amenable variants. Objectives were to characterize effects of estimated glomerular filtration rate (eGFR) on oral clearance (CL), predict doses in mild to moderate renal impairment and in pediatric patients with FD, and to improve designs of FD studies. A 2-compartment model was fit to data from 260 subjects with/without FD and iteratively refined with evolving data. FD, eGFR, and weight affected CL, while weight and FD affected volume. Optimal sampling theory was used to choose pharmacokinetic sampling times for pediatric studies. Doses in patients with renal impairment and in pediatrics were determined by targeting exposure in adults receiving migalastat 123 mg every other day. A clinical study was conducted in 20 adolescent patients with FD ≥45 kg. eGFR had the largest effect on CL. Simulations showed that exposures in moderate renal impairment were within phase 2-3 exposures; patients aged 2-17 years require weight-based dosing; and predicted exposures in adolescent patients ≥45 kg receiving migalastat 123 mg every other day were similar to adults (data confirmed in a clinical study). Model-informed drug development optimized dosing and design of clinical studies and supported that no dose adjustments were needed in patients with mild to moderate renal impairment or in adolescent patients ≥45 kg.