Scintigraphic assessment of the intragastric distribution and gastric emptying of an encapsulated drug: the effect of feeding and of a proton pump inhibitor

SUMMARY Background: Local delivery of therapeutic agents to the stomach may be a useful strategy in the treatment of Helicobacter pylori infection. We aimed to see whether the intragastric distribution and gastric retention of a therapeutic agent could be improved, either by giving omeprazole or by dosing after a meal. Methods: Twelve healthy volunteers took part in this double-blind placebo-controlled crossover study comparing the effects of omeprazole 20 mg twice daily for 5 days with placebo, and the fasted with the fed state, on the gastric emptying and intragastric distribution of a soluble scintigraphic marker contained in a drug capsule. Results: Dosing after food profoundly prolonged gastric residence of the drug label, prolonging mean time to 50% emptying (T50) from 0.5 ± 0.1 h in the fasted state to 2.0 ± 0.2 h when given after food. Food also improved intragastric distribution by increasing delivery to the body and fundus. Omeprazole enhanced the effect of food, prolonging T50 to 2.9 ± 0.3 h, but had no effect in fasted subjects. Conclusions: Dosing after food markedly improves the aspects of local drug delivery to the stomach investigated in this study, and omeprazole enhances this effect. Post-prandial dosing may, therefore, be useful for improving delivery of some anti-Helicobacter agents.