Pharmacodynamics and safety of pantoprazole in neonates, preterm infants, and infants aged 1 through 11 months with a clinical diagnosis of gastroesophageal reflux disease.

Background: Limited data on proton pump inhibitors in infants led regulatory agencies to request sponsors to conduct pediatric studies.

Aim: To determine the pharmacodynamic response to pantoprazole in infants with GERD to aid the dose selection for an efficacy study.

Methods: In two open-label studies, neonates and preterm infants (study 1, ~1.2 mg/kg [high dose]) and infants 1 through 11 months (study 2, ~0.6 [low dose] or ~1.2 mg/kg [high dose]) received once-daily pantoprazole. Twenty-four-hour dual-electrode pH-metry parameters were compared between predose and steady state (≥5 days) (two-sided paired t test). Treatment was administered for ≤6 weeks.

Results: In studies 1 and 2, 21 and 24 patients, respectively, were enrolled for pharmacodynamic evaluation. The high dose provided similar responses in the two studies and improved these parameters significantly: mean gastric pH and percent time gastric pH > 4 increased (p < 0.05 both studies), normalized area under the curve (AUC) of gastric H(+) activity decreased (p < 0.05 study 2), and normalized AUC of esophageal H(+) activity decreased (p < 0.05 both studies). The AUC of esophageal pH < 4 decreased. Normalized AUC of esophageal H(+) activity decreased (p < 0.05 both studies), indicating refluxate pH increased, although this was not reflected in any change in mean esophageal pH or reflux index. The normalized AUC of esophageal H(+) activity was a more sensitive measure of changes in esophageal pH.

Conclusions: In neonates, preterm infants, and infants aged 1 through 11 months, pantoprazole (high dose) improved pH-metry parameters after ≥5 consecutive daily doses, and was generally well tolerated for ≤6 weeks.