Non-compendial vs compendial analytical tests - a powerful tool for predicting in vitro similarity of highly viscous oral suspension

Abstract

In vitro dissolution profiles are increasingly used to evaluate drug release characteristics of pharmaceutical products. The dissolution methods is expected to be an appropriate tool for checking consistency of the pharmaceutical attributes by discriminating similarities and dissimilarities between different drug formulations. Expansion in development of novel “special” dosage forms, due to the manner in which these dosage forms release the active pharmaceutical ingredient, usually requires applying non-compendial dissolution strategy that differs from the traditional compendial recommendations. For demonstrating sameness in the dissolution profile, in vitro drug release comparison between test and reference product of highly viscous oral suspension by applying non-compendial peak vessel against conventional hemispheric vessel was demonstrated in this study. All reference batches exhibited high variability in dissolution data when using hemispheric vessel due to forming mound compact mass at the bottom of the vessel. Different strategies for samples manipulation, before and during dissolution period, were performed in order to eliminate additional variabilities. Modifications of conventional USP 2 apparatus such as using peak vessel provided with more reproducible and reliable result for distinguishing in vitro similarities between different formulations of oral suspensions. Misinterpretation of dissolution data can lead to negative impact on product development. Taking time to observe and evaluate what is happening to the product in the vessel during dissolution is of curtail consideration for proper selection of the dissolution strategy. Keywords: oral suspensions; in-vitro release; hydrodynamic variability; USP apparatus 2/ Paddle apparatus; peak vessel