ABSTRACT
In this study, fluvoxamine maleate sustained-release pellet system tablets were prepared and were used to evaluate their release behaviors in vitro. Fluvoxamine maleate pellets were prepared using centrifugal-spherization method and coated by fluidized bed as bottom-spray. The multi-unit sustained-release pellets and appropriate excipients for prescription volumes were mixed uniformly and then compressed to tablets. Screening and determining the optimal formulation of drug loaded pellets through L8 (24) Taguchi experiment. Using Minitab software to design a DOE experiment with 24 partial factors, including material temperature, fan speed, atomization pressure, and spray rate to optimize the bottom spray coating process. Taking monostearate glycerol ester with a particle size of 24-40 mesh as the main diluent for tableting to relieve the delamination phenomenon between pellets and excipients during tablet pressing and reduce mechanical damage to the coating film. By examining the powder fluidity indexes such as angle of repose, bulk density, tapped density, and Hausner ratio of mixed particles, it was found that the flowability and compressibility are good and suitable for direct compression. Evaluate the basic properties of the sustained-release tablets, investigate the in vitro release behavior and study the release mechanism. The results of in vitro release test showed that the self-made sustained-release tablets could disintegrate into independent pellet units in phosphate buffer at pH 6.8 and release slowly within 24 h, which conformed to the first-order drug release model. The fluvoxamine maleate sustained-release pellet system tablets meet the requirements of preparation design and has a great commercial prospect.
ABSTRACT
OBJECTIVE: To prepare mifepristone gastric retentive multi-unit pellet system (MUPs), and study its release behaviors in vitro. METHODS: A sustained release layer and mucous adhesive layer were coated onto extrusion spherized mifepristone pellets. The gastric retentive sustained release pellets were mixed with granules which were wet granulated from micronized mifepristone and compressed into MUPs tablets. Investigation and evaluation of the in vitro release of mifepristone MUPs tablets were carried out from different aspects. RESULTS: The turning point of pH value for the solubility of mifepristone was 3.0.Micronized mifepristone showed higher dissolving rate and apparent solubility. The gastric retentive mifepristone MUPs tablets had faster release than marketed mifepristone tablets. The in vitro adhesive experiment with pig stomach showed that mucous adhesive mifepristone pellets could be entrapped into the gastric mucous and retained for a long time. The accelerated stability study showed that mifepristone MUPs tablets were as stable as marketed mifepristone tablets. CONCLUSION: Novel mifepristone gastric retentive MUPs tablets are successfully prepared. The release characteristics in vitro indicate that the product may have higher bioavailability than marketed mifepristone tablets with significantly lower variability.