Pharmacokinetics, Safety, and Efficacy of Gadopiclenol in Pediatric Patients Aged 2 to 17 Years.

Objectives: The aim of this study was to evaluate the pharmacokinetic (PK) profile, safety, and efficacy of gadopiclenol, a new high-relaxivity gadolinium-based contrast agent, in children aged 2 to 17 years.

Materials And Methods: Children scheduled to undergo contrast-enhanced magnetic resonance imaging of the central nervous system (CNS cohort) or other organs (body cohort) were included sequentially into 3 age groups (12-17, 7-11, and 2-6 years). Gadopiclenol was administered at the dose of 0.05 mmol/kg. A sparse sampling approach was applied, with 4 blood samples per child collected up to 8 hours postinjection. Population PK modeling was used for the analysis, including the CNS cohort and adult subjects from a previous study. Adverse events were recorded, and efficacy was assessed for all children.

Results: Eighty children were included, 60 in the CNS cohort and 20 in the body cohort. The 2-compartment model with linear elimination from the central compartment developed in adults was also suitable for children. Pharmacokinetic parameters were very similar between adults and children. Terminal elimination half-life was 1.82 hours for adults and 1.77 to 1.29 hours for age groups 12-17 to 2-6 years. The median clearance ranged from 0.08 L/h/kg in adults and 12-17 years to 0.12 L/h/kg in 2-6 years. The median central and peripheral volumes of distribution were 0.11 to 0.12 L/kg and 0.06 L/kg, respectively, for both adults and children. Simulations of plasma concentrations showed minor differences, and median area under the curve was 590 mg·h/L for adults and 582 to 403 mg·h/L for children. Two patients (2.5%) experienced nonserious adverse events considered related to gadopiclenol: a mild QT interval prolongation and a moderate maculopapular rash. Despite the limited number of patients, this study showed that gadopiclenol improved lesion detection, visualization, and diagnostic confidence.

Conclusions: The PK profile of gadopiclenol in children aged 2 to 17 years was similar to that observed in adults. Thus, there is no indication for age-based dose adaptation, and comparable plasma gadopiclenol concentrations are predicted to be achieved with body weight-based dosing in this population. Gadopiclenol at 0.05 mmol/kg seems to have a good safety profile in these patients and could improve lesion detection and visualization, therefore providing better diagnostic confidence.