Effect of rabeprazole (E3810), a novel proton pump inhibitor, on intragastric pH in healthy volunteers

In this study, we examined the effect of rabeprazole (E3810), a novel proto n pump inhibitor, on gastric acidity under physiological conditions in heal thy volunteers using 24-hour intragastric pH monitoring. Twenty-four-hour i ntragastric pH monitoring was performed three times to seven subjects rando mly assigned in a cross over fashion to one of the following groups; withou t drug administration (basal), and with 10 mg or 20 mg of rabeprazole for f our days. The median pH for 24 hours was 2.15 in the basal study, while the corresponding median pH were 5.05 and 5.90 after treatment with 10 mg and 20 mg of rabeprazole, respectively. Significant differences in the median p H were observed between the basal study and that after administration of th e 10 mg and 20 mg doses of rabeprazole. The cumulative percentage of pH rea dings above the threshold pH 4 value, was 34.1% in the basal study, and 72. 6% and 78.3% after treatment with 10 mg and 20 mg doses of rabeprazole, res pectively. This result indicates that the efficacy of rabeprazole allows fo r substantial control of gastric acidity with once-daily dosing, and that b oth the 10 mg and 20 mg doses result in potent inhibition of gastric acid s ecretion. (C) 1998 Tohoku University Medical Press.