Improvement of ursodeoxycholic acid bioavailability by 2-hydroxypropyl-beta-cyclodextrin complexation in healthy volunteers.

Tablets containing the inclusion complex of ursodeoxycholic acid (UDCA) with 2-hydroxypropyl-beta-cyclodextrin were prepared by direct compression. Plasma concentrations of UDCA were determined in six healthy volunteers after oral administration of tablets containing the inclusion complex or UDCA alone (Ursacol). Following the administration of the complex tablets, the mean area under the plasma concentration curve (AUC) and the maximum UDCA plasma concentration (Cmax) were significantly higher than those obtained after the administration of the commercial ones. Moreover, the time of maximum plasma concentration (tmax) appeared at a shorter time. These results may be explained by the increase of the UDCA dissolution rate via complex formation.