title: An open-label, parallel, multiple-dose study comparing the pharmacokinetics and gastric acid suppression of rabeprazole extended-release with esomeprazole 40 mg and rabeprazole delayed-release 20 mg in healthy volunteers.
abstract: BACKGROUND
  Novel rabeprazole extended-release (ER) formulations were developed to provide prolonged gastric acid suppression and potentially improved clinical outcomes in GERD patients.
  
  
  OBJECTIVE
  To evaluate the pharmacodynamics and pharmacokinetics of six rabeprazole-ER formulations vs. esomeprazole 40 mg and rabeprazole delayed-release (DR) 20 mg.
  
  
  METHODS
  Helicobacter pylori-negative healthy subjects were randomised to receive one of eight treatments once daily for 5 days. Twenty-four-hour intragastric pH was monitored on days -1, 1 and 5. Rabeprazole plasma concentrations were measured on day 5.
  
  
  RESULTS
  A total of 248 subjects (N=31/group) were enrolled in the study. On day 5, rabeprazole-ER groups provided mean durations of 18.5-20.2 h (77.0-84.1% of 24-h) with intragastric pH >4.0 vs. esomeprazole 40 mg (15.9 h/66.1% of 24-h) and rabeprazole-DR 20 mg (15.2 h/63.2% of 24-h). A similar increase was observed on day 1. While percentage of daytime (8 am-10 pm) with intragastric pH >4.0 on day 5 was overall similar across the groups, percentage of night-time (10 pm-8 am) with intragastric pH >4.0 was higher with the rabeprazole-ER groups (57.0-72.4%) vs. esomeprazole 40 mg (32.8%) and rabeprazole-DR 20 mg (34.0%).
  
  
  CONCLUSIONS
  Rabeprazole-ER once daily for 5 days demonstrated a significantly longer duration of gastric acid suppression in 24 h vs. esomeprazole 40 mg and rabeprazole-DR 20 mg. The increase in acid suppression was predominantly due to prolonged acid suppression during the night-time; this was supported by the extended-release pharmacokinetic characteristics.
authors.affiliation: St. Mary's Hospital, McGill University, Westmount, Montreal, QC, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Morelli
authors.forename: H
authors.initials: H
authors.lastname: Chen
authors.forename: G
authors.initials: G
authors.lastname: Rossiter
authors.forename: B
authors.initials: B
authors.lastname: Rege
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000008:administration & dosage* / Q000493:pharmacokinetics; D000328:Adult; D000897:Anti-Ulcer Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D003692:Delayed-Action Preparations / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D064098:Esomeprazole / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005260:Female; D005744:Gastric Acid / Q000502:physiology; D005745:Gastric Acidity Determination; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D064750:Rabeprazole; D013223:Statistics as Topic; D055815:Young Adult
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D003692:Delayed-Action Preparations; D064750:Rabeprazole; D064098:Esomeprazole