Functional excipients are critical to the successful application of HME to resolve formulation challenges. Whilst polymers show potential in both controlled release and in improving the solubility and dissolution of poorly soluble compounds they are not ideal materials for extrusion. Lipid excipients are distinctly different to polymers and behave differently in HME. This article highlights two glyceride-esters: Compritol® 888 ATO and Precirol® ATO 5. They melt at relatively low temperatures and recrystallize quickly. They extrude well and can produce strand-like extrudates which can be down streamed into powders or granules.
These glyceride-esters can be used as release retarding agents/dissolution modifiers for both insoluble and soluble drugs even for high drug loading. In combination with plastic polymers they also can act as plasticizer/processing aid enabling lower temperature process and continuous production.
At Gattefossé we aim to share our knowledge to help formulators use lipid excipients to their best advantage.