Physicochemical characterisation of spray dried ternary solid dispersions of simvastatin. Processability, tableting and dissolution

Abstract

Simvastatin(SMV) is poorly soluble drug classified as belonging to Class II of Biopharmaceutics Classification System. Common approach to improve apparent solubility of drugs is production of amorphous solid dispersions (ASD) by means of spray drying(SD) or hot-melt extrusion. Spray drying of low-glass transition temperature(Tg) ASDs is challenging due to the risk of material being exposed to SD outlet temperatures close to its Tg which may result in melting of ASD and subsequent crystallisation of amorphous drug. It was hypothesised that addition of easily-crystallising material to ASD will improve its SD processability. In addition, it was hypothesised that produced ternary solid dispersions (TSD)composed of amorphous composite of drug and the polymer (PVP K17, 55 and 150) and crystalline, soluble nanoparticles (NaCl) will improve dissolution of TSD tablets. The dissolution of SMV from TSDs was faster compared with that of binary solid dispersion in case of SMV-TSDs produced with PVP K55 and 150. The tabletability assessment showed increase in compression led to increase in tensile strength and decrease in porosities of SDs tablets.

Keywords

• intrinsic dissolution
• polyvinylpyrrolidone and sodium chloride
• simvastatin