A Pharmacokinetic and Safety Study of Single and Multiple Doses of Rabreprazole in Pediatric Patients With Gastroesophageal Reflux Disease (GERD) 1 to 11 Years Old, Inclusive

This is an open-label (both the physician and the patient know the name of the study medication), multi-center, Phase 1 study, consisting of 2 parts. The first part of the study will be non-randomized, all patients will receive the same dose. In the second part of the study, patients will be randomized (study medication assigned by chance) into 2 dose groups. The purpose of the study is to evaluate the pharmacokinetics, pharmacodynamics (clinical global impressions and formulation palatability) and safety of rabrepazole after single and multiple daily administration at 2 dose levels in children between the ages of 1 and 11 years, inclusive, with GERD. As this study is an exploratory assessment of the pharmacokinetics, pharmacodynamics and safety of rabeprazole in children, no formal hypothesis testing is applied. Safety and tolerability, including monitoring of adverse events, clinical laboratory results, physical examination, vital signs and ECG measurements, will be evaluated throughout the study. Patients will receive rabeprazole sodium as single daily oral doses for 5 successive days as a bead formulation. Patients in the first part of the study will receive single and multiple daily every 24 hours doses of 0.14 mg/kg, using increments of 1 mg dose. Safety and pk data from part 1 of the study will determine the 2 dosages to be studied in part 2 of the study.