Dissolution Testing as a Prognostic Tool for Oral Drug Absorption: Dissolution Behavior of Glibenclamide

Purpose. The dissolution behavior of two commercially availableglibenclamide formulations was tested in various media. The aim of thestudy was to investigate whether the use of biorelevant dissolutionmedia (BDM) would be advantageous over the use of standard mediafor predicting the in vivo performance of the two formulations.Methods. The dissolution tests were performed using USP 23 apparatus2. Conventional buffers and USP media were compared with two BDMcontaining different amounts of lecithin and sodium taurocholate.Results. The dissolution of two drug powders was highly dependenton wetting, particle size, pH, and the composition of the mediumused. In addition, the dissolution behavior of the two glibenclamideformulations showed differences in all media tested. The dissolutionresults of the two formulations were compared with those from anin vivo bioequivalence study undertaken by the central quality controllaboratory of the German pharmacists (ZL). The bioequivalencecriterion set by the ZL requires more than 80;pc drug release within 10minutes. Results in FaSSIF, one of the BDMs, met the ZL criterionand this medium was also able to discriminate between the twoformulations. This was not the case for the other media tested.Conclusions. The study indicates that BDM are better able to discriminatebetween glibenclamide formulations than standard dissolutionmedia.