Formulation of Diclofenac Sodium Delayed-Release Disintegrating Tablets

The aim of this study was to design diclofenac sodium delayed-release (DR) disintegrating tablets, which upon oral ingestion rapidly disintegrate into DR pellets without affecting drug release pattern. Diclofenac sodium was mixed with microcrystalline cellulose (MCC) and different enteric polymers to produce DR matrix pellets by high-shear pelletization process. The process variables involving the different stages of high-shear pelletization process such as premixing of the solids; liquid addition stage; wet massing stage; and drying stage along with formulation variables including different types and amount of enteric polymers were investigated. Diclofenac sodium DR pellets were successfully prepared in a single step without DR polymer membrane coating and the dissolution profile was comparable with reference product, Voveran®, diclofenac sodium DR tablets. The optimised DR multiparticulates were compressed with tabletting excipients into multiple unit pellet system (MUPS) tablets. The percentage of DR pellets in the tablet compression blend, the different size fraction of filler excipients, the compression machine speed were considered to have less variation in content uniformity in tablets by using a 3³ factorial design. By including an optimum amount of DR pellets in the compression blend containing tabletting excipients of desired size distribution, the tablets with less variation in content uniformity and unaffected drug release profile, at all compression machine speeds is achievable.