The aim of this study was to develop and evaluate a multiparticulate modified release system, composed of minitablets with a sustained release matrix system coated with a pH-dependent release polymer, using mesalamine as a model drug. Polyox® WSR 1105 was the polymer used in the matrix system and Eudragit® L30D55 was used as a pH-dependent polymer. The minitablets (with 20%, 30% or 40% Polyox® concentration) were prepared by dry granulation, which led to good quality minitablets. The developed minitablets were coated in a fluidized bed at 8% of the coating level. Dissolution studies were performed in media that simulated the gastrointestinal tract (pH 1.4, 6.0 and 7.2) and showed that formulations with higher Polyox® concentrations were capable of... |