Affiliation:
1. Anhui Provincial Center for Drug Clinical Evaluation Yijishan Hospital of Wannan Medical College Wuhu Anhui China
2. Wannan Medical College Wuhu China
Abstract
AbstractIntroductionLamotrigine (LTG) is an antiepileptic drug that has been used in pediatric epilepsy as a combination therapy or monotherapy after stabilization in recent years. However, there are significant drug–drug interactions (DDI) between LTG and combined drugs such as carbamazepine (CBZ) and valproic acid (VPA). It is particularly important to consider the risk of DDI in combination therapy for intractable epilepsy in pediatric patients. Therefore, it is necessary to adjust the dosage of LTG accordingly. The aim of this study was to establish and validate a pediatric physiologically based pharmacokinetic (PBPK) model for predicting LTG exposure. The model is designed to explore the potential for quantifying pharmacokinetic (PK) DDI of LTG when administered concurrently with CBZ or VPA in pediatric patients.MethodAdult and pediatric PBPK models for LTG and VPA were developed using PK‐Sim® software in combination with physiological information and drug‐specific parameters, and a DDI model was developed in combination with the published CBZ model. The models were validated against available PK data.ResultsPredictive and observational results in adults, children, and the DDI model were in good agreement. The recommended doses of LTG for preschool children (2–6 years) and school‐aged children (6–12 years) in the absence of drug interactions were 1.47 and 1.2 times higher than those for adults, respectively; 3.1 and 2.6 times higher than those for adults in combination with CBZ; and 0.67 and 0.57 times lower than those for adults in combination with VPA. In addition, plasma exposures in adolescents (12–18 years) were similar to those in adults at the same doses.ConclusionWe have successfully developed PBPK models and DDI models for LTG in adults and children, which provide a reference for rational drug use in the pediatric population.