Formulation and Evaluation of Posaconazole Bilayer Delayed Release Tablets Using Solid Dispersion Technique

Abstract

The aim of present investigation to formulate bilayer tablets of posaconazole by using solvent evaporation technique. Posaconazole belongs to BCS class 2 which has high permeability and low solubility. In order to enhance the solubility of posaconazole solvent evaporation technique was applied where HPMC AS was used as carrier. This tablet consist of two layers of which first layer serves as loading dose which produce immediate release of drug and second layer serves as maintenance dose that provide controlled release of drug. The whole bilayer tablet is coated with Eudragit L30D55 to produce delayed release and protect drug from acid environment in stomach. The drug excipient compatibility study was performed by FTIR and no interaction was found. Croscaramellose was used in immediate release layer as superdisintegrant. Methocel K100M and Methocel E5M are used for sustain drug release in control release layer. The powder blend for evaluated for flow properties like angle of repose, bulk density, tapped density, Carr’s index and Hausner’s ratio which showed good results. Invitro dissolution studies was performed with USP dissolution apparatus 2- Paddle type. Invitro dissolution was performed for 2 hours in 0.1N HCl which showed no drug release followed by 6.8 phosphate buffer for 12 hours. The bilayer tablet showed initial release to provide loading dose of drug followed by controlled release up to 12 hours. Change in concentration of polymer and superdisintegrant showed impact on drug release profile. Increase in concentration of superdisintegrant in immediate release layer showed increased % drug release. Whereas increase in sustain release polymers in controlled release layer showed decrease % drug release. F9 batch showed satisfactory release up to 100% for 12 hours and was selected as best formulation. Reproducible batch for F9 was formulated and called F10 which also showed satisfactory results.