Atorvastatin calcium is an anti-hyper lipidemic drug with poor oral bio-availability (14%) because of extensive hepatic first pass metabolism. Also it has diversity in solid state stability associated with dissolution related problems as it was a poorly soluble drug. The objective of this present research work was to develop a novel gel liquisolid formulation in order to improve solid state stability cum dissolution properties of Atorvastatin calcium.
Liquisolid compacts were prepared by dissolving the drug in non-volatile solvent and converting it into a gel by adding gelling agent. The gel was converted to powder by adding an adsorbent, Neusilin US2. The powder was granulated and finally compressed into tablets. In vivo bioavailability studies of the gel were carried out in comparison with pure drug suspension.
Results & Discussion
Based on the in vitro dissolution tests performed on the liquisolid & direct compression batches of atorvastatin calcium, it was found that there was a significant difference in the dissolution profile of liquisolid formulation over direct compression formulation which were prepared by gel liquisolid technique. The Liquisolid compacts showed faster release compared to pure drug tablets prepared by direct compression. DSC and XRPD studies were performed and they confirmed that the drug was present in amorphous form in Liquisolid compacts. In vivo bioavailability studies confirmed that Liquisolid compact formulations showed higher bioavailability compared to pure drug tablets prepared by direct compression.
- Plasma concentration time profile after oral administration of Liquisolid compact (LS) and direct compression (DC) tablets