Solid Dispersion Technology, Amorphous Solid Dispersion

Combining increased solubility and improved stability for a stable form

Amorphous solid dispersions combine the increased solubility of amorphous material and the improved stability for a more stable solid form. Amorphous API material have higher energy states versus crystalline API but potentially lower physical and chemical stability. Polymers are utilized in spray drying and hot-melt extrusion to improve the solid-state stability of amorphous solid dispersions. Typical advantages of solid dispersions over other technologies for improving dissolution rate, solubility and bioavailability include:

Broad applicability over a diverse compound property space
Accommodates high dose applications for safety studies
Applicable for either tableting or encapsulation as drug product formats
Applicable for extended-release and combination formulations
Readily scalable processing

Advantages of amorphous solid dispersions

Broad applicability
High-dose applications
Tablets (MR, XR) and capsules
Scalability of processes

Amorphous solid dispersion

When a solid dispersion is determined to be the proper approach for addressing bioavailability issues, the choice between spray drying and hot-melt extrusion technologies is typically based on several target product profile and commercial considerations including:

Physical and chemical stability
Drug loading requirements
Food effect and variability
Combination versus single API products
Commercial consideration

Best practices have also been developed for technology transfer between spray drying and hot-melt extrusion. Spray drying is often used for feasibility, preclinical and phase I studies due to lower API requirements versus HME approaches.