Pharmacokinetics and relative bioavailability of valaciclovir hydrochloride tablets in Chinese healthy volunteers

    HU Xiao, ZHANG Hong, XIA Chunª²Hua, CHEN Yueª²Jiang

    Institute of Clinical Pharmacology, Jiangxi Medical College, Nanchang 330006, China

    ¡¾Abstract¡¿ AIM: To study the pharmacokinetics and relative bioavailability of valaciclovir hydrochloride tablets and evaluate its bioequivalence. METHODS: A single oral dose 600 mg of 2 valaciclovir hydrochloride tablets was given to 18 healthy volunteers in an open randomized crossover study. The concentration of acyclovir in plasma was determined by HPLC at different time points within 14 h following administration. The pharmacokinetic parameters were calculated by BAPP 2.0 software and the bioequivalence was evaluated by two oneª²sided t test and 90%confidence intervals. RESULTS: The calibration curve of acyclovir was linear in the range of 0.1~4.0 ¦Ìg/mL (r=0.9999), and an intraª²day and interª²day RSD of<7.00% was observed. The concentrationª²time curve after administration was best fitted to a one compartment open model, and main pharmacokinetic parameters were as follows: Tmax were (1.50¡À0.40) and (1.40¡À0.40) h; Cmax were (2.70¡À0.68) and (2.87¡À0.75) ¦Ìg/mL; t1/2 were (3.00¡À0.65) and (3.28¡À0.67) h; AUC0-14 were 9.07¡À2.43 and 9.71¡À2.70 ¦Ìg¡¤h/mL. The relative bioavailability of the test preparations compared with the reference preparations was (96.4¡À23.7)%. There was no statistically singnificant difference in parameters Tmax, t1/2, Cmax, MRT, AUC0-14 and AUC0-¡Þ between the 2 products (P>0.05). CONCLUSION: The 2 valaciclovir hydrochloride tablets were bioequivalent. ......