In vitro-in vivo evaluation of fast-dissolving tablets containing solid dispersion of pioglitazone hydrochloride

Investigation of in vitro/in vivo behavior of fast-dissolving tablets containing solid dispersions of pioglitazone hydrochloride (PIO) is the focus of the present research work. The effect of various hydrophilic polymers on the aqueous solubility of PIO was studied. Poly vinyl pyrrolidine K 30 (PVPK 30) carrier was selected and solid dispersions were prepared by various methods. Evaluation of solid dispersion for percentage yield, drug content, solubility, and Fourier Transform Infrared-indicated kneading method was most appropriate. Furthermore, the dissolution studies exhibited an enhancement in drug dissolution. One-way ANOVA of in vitro data suggested that there was significant (P <= 0.05) difference in dissolution profile of PIO solid dispersion when compared with pure drug and commercial product. Infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction performed on solid dispersion indicated lack of physicochemical interaction between the drug and the carrier. The selected formulation is compressed into fast-dissolving tablets which were further evaluated for tablet properties and in vitro drug release. In vivo studies of pure drug, selected formulation, and marketed product were carried out in male Wistar rats and pharmacokinetic parameters were calculated using Kinetica software 2000. The best formulation has shown T-max of 1 hour which was highly significant (P < 0.01) when compared with pure drug and marketed formulation. Therefore, the solid dispersions prepared by kneading method using PVPK 30 as hydrophilic carrier can be successfully used for improvement of dissolution of PIO and resulted in faster onset of action as indicated by in vivo studies.