By Dr. Ashish Punia, Ph.D.
Merck & Co., Rahway, NJ

A considerable portion of small molecule pharmaceutical drugs suffer from poor aqueous solubility. Amorphous solid dispersion (ASD) is a leading technology to enhance the aqueous solubility and thus bioperformance of poorly soluble drug. Various ASD approaches have been successfully applied in commercial and development pipeline drug products including spray dried dispersion (SDD), hot melt extrusion (HME), electrospraying and co-precipitated amorphous dispersion (cPAD). cPAD process approach has garnered tremendous research interest due its unique ability to address the inherent process and material characteristic challenges associated with widely utilized SDD and HME manufacturing approaches. Here, we will demonstrate the application of cPAD in three case studies to: a) resolve manufacturing challenges for a pharmaceutical drug with low glass transition temperature; b) obtain high bulk density ASD intermediates to enable downstream process advantages; and c) understand the interplay of surface composition, processing condition and release performance of a hierarchical ASD. These case studies demonstrate the wide utilization of cPAD as an emerging ASD technology to help develop ASDs with enhanced processability and dissolution performance.