CYP2C19 Genotype Predictor of Gastric Acid Suppression
Study Details
Study Description
Brief Summary
If CYP2C19 genotype can predict the efficacy of healing erosive esophagitis and gastric acid secretion in patients taking once a day omeprazole.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
| Early Phase 1 |
Detailed Description
Proton pump inhibitors are metabolized through the CYP2C19 hepatic enzyme system. Several variant genotypes of this enzyme exist which may lead to decreased, normal or increased metabolism of the proton pump inhibitor. With alteration of metabolism, the degree of gastric acid suppression achieved and efficacy in treating reflux could be affected. For example, Asian populations who have low activity of CYP2C19, commonly need lower doses of proton pump inhibitors to manage gastroesophageal reflux because of more sustained blood levels and availability of the drug. Theoretically, those patients who are rapid metabolizers would receive less effective treatment with proton pump inhibitors
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Omeprazole Patients will undergo whole blood testing for CYP2C19 genotype and will be started on omeprazole 40 mg once daily in the morning 30 minutes before breakfast. The Mayo Dysphasia Questionnaire 30 day (MDQ-30day) will be used during the study. At the end of 8 weeks, patients will undergo dual probe pH/impedance testing on therapy and a clinically indicated endoscopy to rule out Barrett's esophagus and assess healing. CYP2C19 genotyping will be performed in the Mayo laboratory. |
Drug: Omeprazole
Patients with LA Grade B-D erosive esophagitis identified at the time of endoscopy will be prospectively recruited. Patients will undergo whole blood testing for CYP2C19 genotype and will be started on omeprazole 40 mg once daily in the morning 30 minutes before breakfast. The Mayo Dysphasia Questionnaire -30 day (MDQ-30day) will be used during the study. At the end of 8 weeks, patients will undergo dual probe pH/impedance testing on therapy and a clinically indicated endoscopy to rule out Barrett's esophagus and assess healing. CYP2C19 genotyping will be performed in the Mayo laboratory.
Other Names:
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Outcome Measures
Primary Outcome Measures
- The correlation specific to CYP2C19 genotype with gastric acid suppression by omeprazole. [8 weeks]
Secondary Outcome Measures
- To assess patients gastrointestinal symptoms, in patients with EoE by means of standard validated questionnaires [30 days]
trouble swallowing, heartburn, acid regurgitation
Eligibility Criteria
Criteria
Inclusion criteria:
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Age 18 or older
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Have either mild-to-moderate Los Angeles (LA) Classification System grade B, moderately severe LA grade C, or severe LA grade D erosive reflux esophagitis
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Or patients having a clinically indicated pH/impedance monitoring on proton pump inhibitor therapy for indications of gastroesophageal reflux disease.
Exclusion criteria:
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Neoplasm of the esophagus or stomach
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Use of drugs that interfere with CYP2C19 metabolism Diazepam, phenytoin, amitriptyline, clomipramine, clopidogrel Cyclophosphamide, progesterone, fluoxetine, fluvoxamine, ketoconazole Lansoprazole, omeprazole, ticlopidine
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Evidence of active H. pylori infection
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Inability to read due to: Blindness, cognitive dysfunction, or English language illiteracy
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Disorders which predispose to unreliable responses such as Schizophrenia, Alzheimer's disease or significant memory loss
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Mayo Clinic in Rochester | Rochester | Minnesota | United States | 55905 |
Sponsors and Collaborators
- Mayo Clinic
Investigators
- Principal Investigator: David Katzka, MD, Mayo Clinic
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 12-008053