ABSTRACT
Ping Gao Small Molecule Pharmaceutics, Amgen, Inc., Thousand Oaks, California, U.S.A.
Walter Morozowich Prodrug/Formulation Consultant, Kalamazoo, Michigan, U.S.A.
INTRODUCTION
Background on Conventional Self-Emulsifying Drug Delivery Systems and the Supersaturatable Formulations
Low water solubility is widely recognized as the main reason for the poor oral absorption of many new chemical entities. Conventional solubilization approaches such as salt formation, cosolvents and, more recently, surfactant-based micellar systems, are now widely employed in enhancing the oral absorption of drugs, primarily poorly soluble drugs. In particular, self-emulsifying drug delivery systems (SEDDS) are commonly employed in improving the oral exposure of poorly soluble, lipophilic drugs (1-5). However, a high surfactant level is needed in the conventional SEDDS formulations in order to prevent precipitation of the drug on dilution with water in the gastrointestinal (GI) tract. The surfactants that are commonly employed in SEDDS formulations can increase the incidence of
GI side-effects (6,7) and, therefore, a reduced amount of surfactant in the formulations should minimize the surfactant-induced GI side-effects (8-10).
