Feature article: Amorphous Solid Dispersion Speciation - Impact of Polymer Chemistry & Drug Properties

The amorphous state is a high-energy physical form that can enhance solubility beyond that of crystalline forms. In an ASD, API is typically for­mulated with a polymer that helps to both maintain the API in the amorphous form in the solid state and may act as a precipitation inhibitor to sustain the amorphous solubility upon dissolution.

Formulation development of ASDs focuses on polymer se­lection, the ratio of drug to polymer, and the design of the ASD particles to develop a system that is physically stable while also demonstrating optimal performance. ASD performance is defined by enhancement in bioavailability, driven by supersaturation of dissolved drug and the formation of drug-polymer colloids. This article focuses on the use of in vitro techniques for character­izing ASD performance and on how these techniques can be used to help better understand the role of polymer chemistry in ASD performance. READ NOW >