Bioequivalence of ritodrine hydrochloride tablets in Chinese healthy volunteers

Objective To evaluate the bioequivalence of two preparations of ritodrine hydrochloride tablets.Methods A single oral dose of 10 mg test and reference ritodrine hydrochloride tablets were given to 22 female healthy volunteers in a randomized crossover study.The concentrations of ritodrine hydrochloride were determined by HPLC-MS /MS method.The pharmacokinetic paramters and relative bioavailability were calculated by DAS 2.0 software,then the bioequivalence was judged.Results The main pharmacokinetic parameters of two preparations were as follows: Cmax were(5.71±1.83),(5.61±2.03) ng·mL-1,Tmax were(0.54±0.45),(0.46±0.24) h,t1/2 were(3.64±3.99),(4.25±4.02) h,AUC0-t were(12.31±5.20),(12.01±5.42) h·ng·mL-1,respectively.The relative bioavailability of test tablets was(105.3±19.96)%.The 90% CIs for the ratios of AUC0-t,Cmax were 95.8%-111.6%,95.4%-108.2%,respectively.Conclusion The results demonstrated that the two preparations were bioequivalent.