Hot Melt Coating: Development and Optimization of Controlled Release Formulation and Process of Oxcarbazepine

Hot-melt coating process (HMCP) is being developed to formulate lipid based oral controlled release formulation system for anti-epileptic drug Oxcarbazepine. Pellets containing Active ingredient in the core portion were prepared by extrusion spheronization process with use of appropriate filler and binder. These core pellets were then coated using hot-melt coating technology with different levels of solid lipid material and a hydrophilic component. Formulation and Process parameters were optimized to achieve targeted drug release profile and other target product profile with particular focus on HMCP. Quality by design (QbD) with DOE approach was used for designing and development of the formulation, by putting risk assessment (FMEA, Fish-bone diagram), screening (by Plackett Burman), and optimization (by CCC) studies. Appropriate ‘design space’ was proposed based on the optimization studies. The results demonstrated that the level of Low melting coating component and a hydrophilic component influenced the drug release rate from the formulation, and the rate of release could be optimized by varying the amount of these components in the formulation. Processing parameters like Temperature of the coating solution and atomization air, Atomization air pressure and Spray rate also affects the drug release rate and other parameters like coating efficiency and mean particle size. For optimized formulation, dissolution data model fitting was also carried out which adequately fits to Higuchi model suggesting that the drug release occurred predominantly by diffusion.