Pharmacokinetics of Immediate-Release vs. Delayed-Release Omeprazole in Gastroparesis

University of Louisville12 enrolled

Overview

The purpose of this study is to compare the blood drug levels of two prescribed medications, immediate-release omeprazole 40 mg powder and delayed-release omeprazole 40 mg capsule to determine which drug is better absorbed in patients with a slow stomach emptying (gastroparesis). Delayed-release omeprazole has a protective coating to prevent the drug omeprazole from being neutralized by stomach acid. Immediate-release omeprazole has sodium bicarbonate (antacid) which neutralizes the stomach acid, eliminating the need for a protective coating. Immediate-release omeprazole suspension may have a more rapid pharmacokinetic profile and greater overall drug absorption in gastroparesis.

Hypothesis: Immediate-release omeprazole suspension may have a more rapid pharmacokinetic profile and greater overall drug absorption in gastroparesis. This will result in shorter time to maximal drug concentration, greater maximal concentration, and greater total area under the curve of the concentration vs. time plot. Primary Objective: To compare the pharmacokinetics of omeprazole between immediate-release suspension and delayed-release capsules in patients with heartburn associated with gastroparesis. Study design: randomized, open-labeled, crossover treatment for 7 days with 10-14 days washout. Pharmacokinetic studies will be performed after 7 days on study drug.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Gastroparesis

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Symptoms of heartburn \>2 days per week off antireflux therapy, defined by "a burning feeling rising from the stomach or lower chest up towards the neck" * Symptoms of gastroparesis \>1 month in duration, defined by nausea, vomiting, bloating, dyspepsia, early satiety, or effortless regurgitation. * Prior abnormal 4-hour gastric emptying scan within the past 3 years Exclusion Criteria: * History of esophageal or gastric surgery * Severe gastroparesis with any of the following: vomiting with dehydration requiring IV hydration, hospitalization, weight loss \>10 % pre-illness weight, requiring feeding jejunostomy tubes * Presence of gastric electrical stimulator * Symptoms of retching with vomiting more than 2 days per week * Diagnosis of diabetes * Disorders of small bowel motility (such as pseudo-obstruction or dumping syndrome) * Disorders of small bowel absorption * Diagnosis of gastric outlet, small bowel or colon mechanical obstruction * Diagnosis of acid hypersecretory syndrome * Disorders affecting proton pump inhibitor metabolism (such as liver failure) * Known allergy or side effects to proton pump inhibitor * Non-ambulatory patients: bed-ridden, nursing home resident, etc. * Pregnancy

Outcomes

Primary Outcomes

Time to Maximal Omeprazole Concentration (Tmax)

Time to max concentration for Immediate release vs. Delayed release omeprazole

Time frame: 10, 20, 30, 45, 60, 90, 120, 150, 180, 210, 240 and 300 min after the study drug was ingested on day 7 of treatment

Maximal Concentration of Omerazole

Maximal concentration of immediate-release vs. delayed-release omeprazole

Time frame: 10, 20, 30, 45, 60, 90, 120, 150, 180, 210, 240 and 300 min after the study drug was ingested on day 7 of treatment

Area Under the Curve for Omeprazole Plasma Concentration

The area under the curve for omeprazole concentration-time curve for immediate release and delayed release omeprazole.

Time frame: 0 to 5 hrs after the study drug was ingested on treatment day 7