Consistency evaluation of domestic generic rifampicin capsules and reference drug in vitro

This study was to evaluate quality consistency of domestic generic and reference preparations. Content and related substances of domestic generic preparations and reference preparation were inspected according to Chinese Pharmacopeia 2015. Then the basic solution for determining dissolution curve was established through preliminary experiment and validation for determination. The dissolution curves of domestic rifampicin capsules and reference preparation were compared in four dissolution mediums: HCl(pH 1. 2), PBS(pH 4. 0), PBS(pH 6. 8)and pure water, respectively. Results showed that the content and related substances of domestic generic and reference preparations complied with the quality standard, but impurity profile displayed that impurities in domestic generic preparations were less than those in the reference preparation, with the content of rifampin quinine being especially less. Furthermore, dissolution of domestic generic and reference preparations were compared, and their dissolution curves were not similar. It is suggested that consistency between domestic rifampicin capsules and reference preparation should be evaluated by bioequivalence test.