Currently, East African Community (EAC) member states do not have capacity to carry out studies known as bioequivalent (BE) studies for generic (copy of the original brands) medicines. These studies are very important as they show whether generic medicines are basically the same with original brands. Due to lack of this capacity the quality of locally manufactured medicines may not be fully known. This study intends to conduct a BE study of a locally produced medication called enalapril (which is a drug for treatment of high blood pressure) a key step towards enforcement of BE requirements in East Africa. The study will enroll fourteen (14) healthy adult volunteers aged 18-55 years^. Both drugs, brand and generic will be sourced from a registered distributor. The reference pharmaceutical product (or the original product) will be Enam™ 5mg tablets while the local generic product will be Cardace™ 5mg. One tablet of either the Cardace™ 5mg or Enam™ 5mg will be given by mouth to the volunteers with 240 mL of water. A 5.0 mL blood sample for the enalapril assay will be drawn into EDTA-K3 anticoagulant tubes before and after taking medication. The blood samples will be processed and kept frozen. After seven days, the study will be repeated in the same manner with the alternative medication being tested. Blood samples will be analyzed for enalapril using a machine known as LC MS/MS. The scientists will then carry out calculation to determine the similarity between the generic and original products of enalapril tablets. The results of this study will be shared with the Pharmacy & Poisons Board (the national Drug Regulatory Authority) as part of policy enforcers, for their information. However, our results will not affect the drugs registration status.

The East African Community (EAC) member states do not as a requirement conduct bioequivalent (BE) studies for generic medicines hence the quality of most of locally manufactured generic drugs is not fully established. This study aims to conduct a BE study of a locally-produced brand of enalapril 5mg tablets as an initial step of introduction of BE studies in EAC. The study will be an open-label, non-replicated, two-sequence, two-period crossover design with a seven-day washout period between each treatment phase. The study will enroll fourteen (14) healthy male adult volunteers aged 18 - 55 years with a body mass index of between 20and 30 kg/m^2.Both drugs, brand and generic will be sourced from registered distributor. The reference pharmaceutical product will be Enam™ 5mg tablets while the local generic product will be Cardace™ 5mg tablets. One tablet of either the Cardace™ 5mg or Enam™ 5mg will be given orallyto the volunteers with 240 mL of water. A 5.0 mL blood sample for the enalapril assay will be drawn at time 0, 0.5, 1.0, 1.75, 2.25, 3,3.75, 5, 8, 12, and 24  hours dosing. The blood samples will be centrifuged at 1000 g for 10 minutes at room temperature and serum stored frozen at -35°C. After seven days, the study will be repeated in the same manner to complete the crossover design. Serum samples will be analyzed for enalapril plus its metabolite enaprilat, and the internal standard according to a validated Liquid chromatography-tandem mass spectrometry method.The following pharmacokinetic parameters will be calculated:elimination rate constant (Ke), maximum concentration (Cmax), time at maximum concentration (Tmax), elimination half-life (T_1/2), area under the curve at time t (AUC0–t), and area under the curve extrapolated to infinity (AUC0–∞).Bioequivalence will be assessed by means of an analysis of variance (ANOVA) of the crossover design and estimating 90% confidence intervals for the ratio of the means of the test/reference products using log-transformed data. For AUC, the 90% confidence interval should be within the acceptance range 80-125%.