Actarit Hydrogel Sustained-release Tablets

Actarit is a new antirheumatic agent . Its antirheumatism mechanism is different from other antirheumatic agent. Actarit could alleviate symptom by regulate immune system, and be classfied as DMARDS agent . Two sustained release tablets with once and twice daily administration(named ActA and ActB) were prepared by using hydropropyl methylcellulose as basic matrix material and other excipients. Different kinds of scientific methods in vivo and in vitro were used to evaluate the self-made sustained release tablets.Actarit solubilities in different solvent and stability were determined .Based on UV method, the analytical method in vitro of Actarit sustained- release tablets was set up. The determination of drug plasma concentation was performed with HPLC. Methods were demonstrated convenient, rapid, and suitable to the study.The effect of different formula composition, preparation procedure and dissolution condition on the drug release from the formulation was studied by determining the cumulative release of 0-14hr and 0-12hr respectively . Based on single-factor tests, the optimal formulation was obtained by 3⁴ factors-analysis orthogonal. The release mechanism of Actarit from matrixe was also studied, and the result of which showed that the release mainly depended on non-Fickian mechanism, namely synergic effect of diffusion and erosion. But there were some differences in proportion of diffusion and erosion in two sustained release tablets.With three crossover design, the pharmacokinetics of Actarit sustained release tablets in dogs was studied comparing with the reference tablet. The mean residence time (MRT) and T_max of ActA and ActB were notablely decreased, and the relative bioavailability were ( 94.54± 17.62 ) %and(103.33 ±21.66)% respectively. It was demonstrated that the two sustained release tablets both were bioequivalent to reference tablet and have better in vitro-in vivo correlation...