Review article: immediate-release proton-pump inhibitor therapy--potential advantages

Area of Science:

• Pharmacology
• Gastroenterology

Background:

• Oral proton-pump inhibitors (PPIs) typically have delayed absorption due to enteric coatings, which protect acid-labile drugs but also delay their antisecretory effect.
• This delay can impact the speed at which therapeutic acid suppression is achieved.

Purpose of the Study:

• To provide an overview of the pharmacokinetics and pharmacodynamics of a novel immediate-release omeprazole formulation.
• To compare the potential advantages of this immediate-release omeprazole over conventional delayed-release PPIs.

Main Methods:

• Pharmacokinetic and pharmacodynamic analysis of immediate-release omeprazole (IR-OME).
• Comparison of C(max) and t(max) between IR-OME and delayed-release omeprazole.
• Assessment of 24-hour intragastric pH profiles after steady-state dosing.

Main Results:

• Immediate-release omeprazole demonstrated a higher mean peak plasma concentration (C(max)) and a significantly shorter mean time to reach C(max) (t(max)) compared to delayed-release omeprazole.
• A single daily dose of 40 mg IR-OME resulted in a median intragastric pH above 4.0 for 18.6 hours/day at steady-state.
• The presence of sodium bicarbonate in IR-OME protects omeprazole from gastric acid and may accelerate proton pump activation through rapid acid neutralization.

Conclusions:

• Immediate-release omeprazole provides rapid absorption and a faster onset of antisecretory effect.
• This rapid action is attributed to the protective effect of sodium bicarbonate against gastric acid.
• IR-OME achieves accelerated acid suppression without compromising the overall duration of acid control.