Physicochemical Characterization and Oral Dosage Form Selection Based on the Biopharmaceutics Classification System

Identifying an active lead molecule, selecting a viable drug candidate and developing a marketable product are profoundly influenced by molecular properties and dosage form design. This chapter discusses the importance of a molecule's physicochemical properties and the link with oral dosage form design strategies. The Biopharmaceutics Classification Scheme (BCS) is used to identify oral dosage form options that have the best chance of overcoming drug delivery problems. Physicochemical characterization not only can guide the selection of formulation strategies but also, if incorporated into the lead selection process, can influence analog selection and lead optimization. The end result of considering physicochemical properties is to reduce the risk of failure by facilitating the identification of appropriate dosage form design options and, at the same time, allow discovery chemists to maximize chances of identifying commercially viable leads. Keywords: absorption; bioavailability; formulation; permeability; solid forms; solubility; stability