FORMULATION AND CHARACTERIZATION OF ATORVASTATIN SOLID DISPERSIONS FOR IMPROVED BIOAVAILABILITY

Solid dispersions (SDs) of atorvastatin (ATS) using PEO-PPO blockcopolymer resulted in the formation of an amorphous product with enhanceddissolution and bioavailability. Solubility enhancement was observed in thepresence of selected carriers and it increased with the increase inconcentration of carriers. The carrier and the active ingredient are dissolvedin a suitable organic solvent is evaporated to an elevated temperature orunder vaccum. As the solvent is being removed, super saturation occursfollowed by simultaneous precipitation of the constituents resulting in asolid residue. The solvent-based process uses organic solvent to dissolve andintimately disperse the drug and carrier molecule The accumulativesolubility of atorvastatin (ATS) from PEO- PPO block copolymer(Poloxamer 188) was found to be superior from glyceryl monostearate andPEG 4000 carriers due to increased content which played major role insolubility enhancement thus improving dissolution rate of SD2 batch withmaximum drug release (98.08 %) in 120 minutes. The optimized SDs werecharacterized by saturation solubility study, drug content, in vitrodissolution, fourier transform infra-red spectroscopy, scanning electronmicroscopy, and x-ray diffraction. Capsules containing optimized SDs wereprepared and compared with marketed brand (LIPITOR®). Finally it can beconcluded that optimized SDs of ATS ameliorate the solubility anddissolution of drug. Since the batch SD2 elicited superior results, it can beproposed as good candidate for systemic product development.