Pharmacokinetics
The mean plasma concentration-time curves are illustrated inFigure 2 (fasting) and Figure 3 (fed). A biphasic decline manner was shown, which initially decrease rapidly and described a somewhat decrease. Besides, the concentration-time curve of gefitinib was similar as for R and T formulations. Pharmacokinetic parameters of gefitinib under fasting and fed conditions were presented inTable 2 . AUC0-t accounted for ≥90% of the total AUC0-∞ for all subjects, indicating that the plasma concentration-time profiles were represented nicely. The CV values of the pharmacokinetic parameters were similar with more than 50%. It is noted that the mean Cmax and AUC were in the range of 208.01-260.05 ng/mL, 6520.42-7334.52 h*ng/mL. In addition, the meant t1/2 was in the range of 29.50-35.10 hour. Moreover, no significant differences were detected in either the absorption or elimination phases of the R- and T-formulations of gefitinib, with similar values of pharmacokinetic parameters under fasting and feeding conditions. Figure 2 and Figure 3 also demonstrated the generally consistent absorption as described using concentration-time curve of post-administration of 12 hour.