Application of hot melt extrusion for improving bioavailability of artemisinin a thermolabile drug

Hot melt extrusion has been used to produce a solid dispersion of the thermolabile drug artemisinin. Formulation and process conditions were optimized prior to evaluation of dissolution and biopharmaceutical performance. Soluplus (R), a low T-g amphiphilic polymer especially designed for solid dispersions enabled melt extrusion at 110 degrees C although some drug-polymer incompatibility was observed. Addition of 5% citric acid as a pH modifier was found to suppress the degradation. The area under plasma concentration time curve (AUC(0-24h)) and peak plasma concentration (C-max) were four times higher for the modified solid dispersion compared to that of pure artemisinin.