title: Combined analysis of three crossover clinical pharmacology studies of effects of rabeprazole and esomeprazole on 24-h intragastric pH in healthy volunteers.
abstract: OBJECTIVE
  To compare antisecretory effects of rabeprazole and esomeprazole after single and repeat dosing in Helicobacter pylori-negative healthy volunteers.
  
  
  METHODS
  Results were pooled from three smaller, open, crossover, randomized studies to obtain data from 80 subjects. The studies compared: (a) 5 days' dosing of 20 mg rabeprazole and esomeprazole (n = 24); (b) single doses of rabeprazole 20 mg and esomeprazole 40 mg (n = 27) and (c) 5 days' dosing of rabeprazole 10 mg and esomeprazole 20 mg (n = 29). Washout periods were > or =14 days. Intragastric pH was recorded continuously for 24 h on days 0, 1 and 5.
  
  
  RESULTS
  Single doses of rabeprazole 20 mg maintained 24-h intragastric pH >4 for longer than esomeprazole 20 mg (45% vs. 32%; P < 0.001); rabeprazole 20 mg and esomeprazole 40 mg were equivalent in their effects. After 5 days' dosing, rabeprazole 20 mg maintained pH >4 for longer than esomeprazole 20 mg (62% vs. 56%; P = 0.046); the reverse was true for esomeprazole 20 mg vs. rabeprazole 10 mg (56% vs. 48%; P = 0.035). In general, intragastric pH AUC during 0-5 h after dosing was higher after esomeprazole than rabeprazole, whereas the reverse was true during the night.
  
  
  CONCLUSIONS
  The order of effects on 24-h pH was: rabeprazole 10 mg < or = esomeprazole 20 mg < rabeprazole 20 mg = esomeprazole 40 mg. Esomeprazole acts faster, whereas rabeprazole's effect lasts longer.
authors.affiliation: Hammersmith Medicines Research, Central Middlesex Hospital, London, UK.
authors.forename: V
authors.initials: V
authors.lastname: Norris
authors.forename: K
authors.initials: K
authors.lastname: Baisley
authors.forename: K
authors.initials: K
authors.lastname: Dunn
authors.forename: S
authors.initials: S
authors.lastname: Warrington
authors.forename: A
authors.initials: A
authors.lastname: Morocutti
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000494:pharmacology*; D000328:Adult; D000897:Anti-Ulcer Agents / Q000494:pharmacology*; D018592:Cross-Over Studies; D064098:Esomeprazole / Q000494:pharmacology*; D005260:Female; D005745:Gastric Acidity Determination; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008297:Male; D064750:Rabeprazole
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D064750:Rabeprazole; D064098:Esomeprazole