Phenobarbital Bioequivalence in Chinese Population: Considering the Role of Food on Pharmacokinetics

Epilepsy is one of the most severe neurological disorders in the world, which might seriously endanger the lives of patients. Phenobarbital is an important medicine clinically used for the treatment of epilepsy, and it is irreplaceable in the treatment of generalized tonic-clonic seizures, focal seizures, status epilepticus, and pediatric epilepsy. However, the original research medicine of phenobarbital has not been launched in China. Therefore, an economical and effective generic medicine is of great significance to patients. In this study, a single-center, randomized, open-label, single-dose, two-formulation, two-period, two-sequence crossover design and parallel design were adopted. The phenobarbital tablets produced by Shandong Xinhua Pharmaceutical Co., Ltd. were used as the test formulation, and Phenobal produced by Fujinaga Pharmaceutical Co., Ltd. was used as the reference formulation for a bioequivalence study. Additionally, the influence of food on the pharmacokinetic parameters al was investigated. The results showed that the test formulation and the reference formulation were bioequivalent, and food might reduce the C_max (maximum concentration) and exposure of phenobarbital. This study provides data support for the marketing of generic phenobarbital medicines and offers a theoretical basis for the rational administration of phenobarbital. The clinical trial was registered in Chinese Clinical Trial Registry (Registration numbers: CTR20242404 and CTR20244155).