Bioequivalence evaluation of two omeprazole enteric-coated formulations inhumans

Omeprazole, a proton pump inhibitor, effectively suppresses the gastric aci d secretion in the parietal cells of the stomach. Several previously publis hed papers focus on the pharmacokinetics of the drug and its interactions w ith physiological aspects or with other drugs. The increasing number of ome prazole containing products available in the market, raises questions of th erapeutic equivalence and/or generic substitution. The bioequivalence evalu ation between two or more formulations provides information about in vivo p erformance. In a favorable decision regarding bioequivalence, the products are considered to have a similar therapeutic efficacy when used under the s ame therapeutic conditions. This paper reports the design, results and some important aspects involved in a bioequivalence study between two solid ora l formulations from different manufacturers. Some important findings were t he high intra-suject variability observed for C-max and the variability obs erved between subject profiles, probably caused by the multi-unit type of f ormulations studied. (C) 1999 Elsevier Science B.V. All rights reserved.