Study of a novel disintegrable oleanolic acid-polyvinylpolypyrrolidone solid dispersion

Novel solid dispersions of oleanolic acid-polyvinylpolypyrrolidone (OLA-PVPP SDs) were designed and prepared to improve the apparent solubility of drug, as well as to improve the stability, fluidity and compressibility of SDs. Disintegrable OLA-PVPP SDs were then evaluated both in vitro and in vivo. DSC, XRD, IR and SEM analysis proved the formation of OLA-PVPP SD and its amorphous state. The results of fluidity study, moisture absorption test and stability test showed that OLA-PVPP SD with good fluidity and qualified stability was successfully obtained. Meanwhile excellent dissolution rate was achieved for in vitro studies; dissolution test showed that similar to 50-75% of OLA was dissolved from SDs within the first 10min, which is about 10-15 times of free OLA. In vivo study indicated that the formation of solid dispersion could largely improve the absorption of OLA, resulting in a much shorter T-max (p < .05) and higher C-max (p < .01) than those of free drug. The AUC(0 ->infinity) of OLA-PVPP SDs (1:6) were 155.4 +/- 37.24 h.ng/mL compared to the 103.11 +/- 26.69 h.ng/mL and 94.92 +/- 13.05 h.ng/mL of OLA-PVPP physical mixture (1:6) and free OLA, respectively. These proved PVPP could be a promising carrier of solid dispersions and was industrially feasible alternative carrier in the manufacture of solid dispersions.