Abstract
The purpose of the present study was to evaluate the bioequivalence of two risperidone tablets, Risperdal (Janssen Korea Co., Ltd.) and Rispen (Myung In Pharm. Co., Ltd), according to the guidelines of Korea Food and Drug Administration (KFDA). The risperidone release from the two risperidone formulations in vitro was tested using KP VIII Apparatus II method with various of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty four healthy male subjects, $23.33\;{\pm}2.10$ years in age and $69.24{\pm}8.05\;kg$ kg in body weight, were divided into two groups and a randomized $2\;{\times}\;2$ cross over study was employed. After one tablet containing 2 mg as risperidone was orally administered, blood was taken at predetermined time intervals and the concentrations of risperidone in serum were determined using HPLC method with UV detector. The dissolution profiles of two formulations were similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t$,$C_{max},\;and\;T_{max}$ were calculated and ANOVA test was utilized for the analysis of the parameters using logarithmically transformed $AUC_t$,$C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the Risperdal were 0.20, -1.29 and -11-09% for $AUC_t$,$C_{max},\;and\;T_{max}$, respectively There were no sequence effects two formulations in parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g.,$log(0.90){\sim}log(1.30)$ and $log(0.84){\sim}log(1.09)$ for$AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA guideline for the bioequivalence were satisfied, indicating Rispen tablet and Risperdal tablet were bioequivalent.
