Pharmacodynamics and kinetics of omeprazole MUPS 20 mg and pantoprazole 40mg during repeated oral administration in Helicobacter pylori-negative subjects

Background: Omeprazole has become available in a tablet formulation, a Mult iple Unit Pellet System (MUPS) containing a large number of small individua lly enteric-coated micropellets. Aim: To compare the acid-inhibitory effect of omeprazole MUPS 20 mg with pa ntoprazole 40 mg and to describe the pharmacokinetics of both drugs followi ng administration on day 1 and day 6. Methods: Randomized, two-way crossover study, Sixteen Helicobacter pylori-n egative healthy subjects, whose gastric acidity fell below pH 4 for 70% of a 24-h baseline period were included, Intragastric pH was measured continuo usly, Results: On day 1 both drugs significantly raised median 24-h gastric pH co mpared to baseline. Median pH and percentages of time above pH 3 and 4 on d ay 1 and day 6 of administration were not significantly different, with the exception of median daytime pH on day 6, which was significantly higher wi th omeprazole (4.65 vs. 4.05), AUC and C-max of omeprazole were significant ly increased on day 6. AUC and C-max of pantoprazole were not significantly increased. Conclusions: No significant difference in acid-inhibitory effect on day 1, On day 6 median daytime pH was significantly higher with omeprazole MUPS, b ut the percentages of time spent above pH 3 and 4 were not significantly di fferent. The significant increase in bioavailability of omeprazole may cont ribute to the increased effect on day 6.