Effects of rabeprazole, 20 mg, or esomeprazole, 20 mg, on 24-h intragastric pH and serum gastrin in healthy subjects

Aim : To compare the antisecretory effects of rabeprazole and esomeprazole in an open, randomized, two-way crossover, clinical pharmacology study. Methods : Twenty-four healthy subjects (14 men, 10 women; mean age 26.8 years) received rabeprazole 20 mg or esomeprazole 20 mg daily on days 1–5, witha 14-day ‘wash-out’. Intragastric pHwasrecordedcontinuously, and serum gastrin measured, on days 0, 1 and 5. Results : On day 0, mean intragastric pH AUC was significantly higher before the esomeprazole than before the rabeprazole treatment in four of the five time intervals analysed. On days 1 and 5, mean intragastric pH AUC was higher after rabeprazole than esomeprazole during 5–11, 14–24 and 0–24 h after dosing. Mean pH AUC in the first 5 h after dosing on day 5 was higher after esomeprazole than rabeprazole (P=0.012). On day 1, mean per cent times pH > 3 and > 4 were significantly greater after rabeprazole than esomeprazole during 0–14, 14–24 and 0–24 h. On day 5, mean serum gastrin AUC0-4 was higher (P = 0.017) after rabeprazole than esomeprazole (335 vs. 316 pg/mL.h). Conclusion : In this clinical pharmacology study, rabeprazole 20 mg daily was more effective than esomeprazole 20 mg daily in increasing intragastric pH and maintaining pH > 3 and > 4. On day 5, mean pH AUC was higher after esomeprazole than rabeprazole.