title: Acid inhibition effect of ilaprazole on Helicobacter pylori-negative healthy volunteers: an open randomized cross-over study.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effects and safety of different doses of ilaprazole on healthy volunteers without a Helicobacter pylori infection.
  
  
  METHODS
  A total of 12 healthy Chinese volunteers were enrolled and divided into four groups randomly, with a 5-day treatment of oral ilaprazole 5mg, 10mg and 20mg or omeprazole 20mg, respectively. After an interval of a 14-day washout phase, each was switched to another dose group and eventually completed all four regimens. The percentage time of intragastric pH>4 was the major index. The polymorphisms of the metabolic enzyme CYP2C19 in these volunteers were also detected.
  
  
  RESULTS
  The percentage time of intragastric pH>4 in the ilaprazole 5, 10 and 20mg groups were 80.4%, 88.1% and 91.0%, respectively, during the first 24h, compared to that of the 20mg omeprazole group (76.6%, P>0.05). Ilaprazole 20mg provided a significant higher mean 24-h pH than that of the same dose of omeprazole both on Day 1 (7.78 vs 6.67, P<0.01) and Day 5 (7.95 vs 7.44, P<0.05). No CYP2C19-dependent difference or obvious adverse effect were found in any ilaprazole groups.
  
  
  CONCLUSIONS
  Low dose ilaprazole offers a gastric acid inhibition comparable to a routine dose of omeprazole, and further investigations in patients with acid-associated diseases are needed.
authors.affiliation: Department of Gastroenterology Department of Clinical Pharmacology, Shanghai, China.
authors.forename: Yi Qi
authors.initials: YQ
authors.lastname: DU
authors.forename: Wen Yuan
authors.initials: WY
authors.lastname: Guo
authors.forename: Duo Wu
authors.initials: DW
authors.lastname: Zou
authors.forename: Xian Bao
authors.initials: XB
authors.lastname: Zhan
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.forename: Jin Hong
authors.initials: JH
authors.lastname: Hu
authors.forename: Yan Fang
authors.initials: YF
authors.lastname: Gong
authors.forename: Jia
authors.initials: J
authors.lastname: He
authors.forename: Jian Ping
authors.initials: JP
authors.lastname: Lu
authors.forename: Zhao Shen
authors.initials: ZS
authors.lastname: Li
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D001562:Benzimidazoles / Q000008:administration & dosage* / Q000009:adverse effects*; D018592:Cross-Over Studies; D065731:Cytochrome P-450 CYP2C19; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D016480:Helicobacter pylori; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects*; D008297:Male; D009853:Omeprazole / Q000008:administration & dosage; D011110:Polymorphism, Genetic; D054328:Proton Pump Inhibitors; D012016:Reference Values; D013270:Stomach / Q000187:drug effects*; D013454:Sulfoxides / Q000008:administration & dosage* / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D001562:Benzimidazoles; D004791:Enzyme Inhibitors; D054328:Proton Pump Inhibitors; D013454:Sulfoxides; C119615:ilaprazole; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D009853:Omeprazole