PEG 400 oral solution and PVPVA solid dispersion suspension were orally administered to rats under fasted conditions at doses of 0.3 mg/head or 1 mg/kg, respectively. The results of the rat pharmacokinetic study are shown in Table and Fig. . Both the oral solution and solid dispersion suspension was efficient, with BA approaching 100%. Thus, both the oral solution and solid dispersion suspension are solubility enhanced formulations that can be used for human ADME studies. Here, we discuss the selection criteria for the two formulations. Solid dispersions can be developed as typical dosage forms of tablets or capsules, which can be proposed as to-be-marketed oral formulations.