In vitro Bioequivalence Study of Five Generic Products and the Innovator Brand of Mebeverine Hydrochloride Extended- Release Capsules in Iran Market

Abstract

Physicians tend to prescribe brand-name medicines for treating specific diseases. This might be due to the better clinical effects of these medicines compared to the generic ones. The aim of the present study was to evaluate in vitro bioequivalency between five generic products (T1, T2, T3, T4, T5) of mebeverine 200 mg extended-release capsules marketed in Iran and the innovator brand (Colofac® retard, Abbott Healthcare SAS, France). To evaluate the differences between generic products and the innovator brand, weight variation and dissolution analysis were performed. Acceptance value was calculated to investigate weight variation between different products. Dissimilarity factor (f1 ) and similarity factor (f2 ) were calculated to differentiate between the dissolution profile of the innovator brand and generic products. Innovator brand and all the generic formulations passed the United States Pharmacopoeia (USP) weight variation test. However, dissolution results indicated that among five generic formulations only T1, T4 and T5 were similar to the innovator brand but T2 and T3 did not pass USP requirements. Some pharmaceutical formulations may pass the pharmacopeia requirements but might show significant differences through in vitro equivalence studies. These differences could result in clinically diverse effects. Moreover, dissolution analysis seems to be a suitable procedure to detect these variations.