Rheological Properties and Process Temperature Prediction for the Hot Melt Extrusion of Artesunate with Soluplus®/Span®20.

The Active Pharmaceutical Ingredients (API) are highly sensitive molecules and generally have low water solubility and must have their biological performance preserved and enhanced by any process. Hot-melt Extrusion (HME) is one of the preferred methods of preparing Amorphous Solid Dispersions (ASD) for poorly soluble APIs. For HME, the Temperature Profile of Extrusion (TPE) is fundamental to predicting the processability of the mixture among API, polymer, and other ingredients. Dynamic rheological studies can determine the initial TPE from the Soft Point of Mixture (SPM) and the Initial Fusion Plato Temperature (IFPT) by the method of Talmadge-Fitch. Using this approach, the work sought the best extrusion conditions to make blends of Artesunate (AS), Soluplus®, and Span®20 compositions using rheological, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis. Rheology studies associated with conventional ASD formation analysis is a powerful tool for fast and high performance in the extruder. This work shows that using rheology to find the softness point of the mixture is a good tool to set up a fine temperature extrusion profile.