What side effects are associated with this type of intervention?

Common treatments affected by CYP2C19 genetic variants include medications like diazepam, clopidogrel, and certain antidepressants. Known side effects of these treatments can vary based on the individual's CYP2C19 genotype. For example, poor metabolizers of diazepam may experience prolonged sedation and increased risk of adverse effects such as dizziness and cognitive impairment. Clopidogrel's efficacy can be reduced in poor metabolizers, leading to a higher risk of cardiovascular events. Antidepressants metabolized by CYP2C19 may cause side effects like nausea, headache, and insomnia, with variations in severity depending on the metabolic rate.

What prior FDA approvals exist?

The FDA has recognized the importance of CYP2C19 genetic variants in drug metabolism, particularly for medications like clopidogrel, where genetic testing can help predict therapeutic response. While there are no specific FDA-approved treatments targeting CYP2C19 genetic variants, the agency has provided guidelines for using genetic information to optimize drug therapy. This includes adjusting dosages or selecting alternative medications based on a patient's CYP2C19 genotype to improve efficacy and reduce adverse effects.

What other types of research exist?

Promising alternatives to limonene metabolism measurement for assessing CYP2C19 genetic variants include: 1) Saliva-based genetic testing, which is non-invasive and can accurately identify CYP2C19 variants. 2) Buccal swab tests, which are easy to administer and provide reliable genetic information. 3) Blood-based pharmacogenomic assays, which, although minimally invasive, offer comprehensive genetic profiling and can be integrated with routine clinical workflows.

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Limonene Metabolism and CYP2C19 Genetic Variants

N/A

Recruiting

Research Sponsored by Stanford University

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Age range: Greater than 18 years and less than 45 years

Be between 18 and 65 years old

Must not have

Past medical history of cerebrovascular or cardiovascular disease

Age less than 18 years old or age greater than 45 years old

Timeline

Screening 3 weeks

Treatment Varies

Follow Up 2 hours

Awards & highlights

No Placebo-Only Group

Summary

This trial tests a way to identify people with certain genetic traits by measuring a substance in their breath after drinking orange peel extract.

Who is the study for?

This trial is for men and women of East Asian ethnicity, aged between 18 and 45 years. It aims to find out if a simple test can be made to check genetic differences affecting how the body handles certain substances.

What is being tested?

The study is testing whether limonene, a common substance found in citrus oils, can help develop a non-invasive tool to screen for genetic variants that affect drug metabolism.

What are the potential side effects?

Since this trial involves measuring metabolism rather than treating disease, side effects are not the main focus. However, any potential mild reactions from exposure to limonene will be monitored.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

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I am between 19 and 44 years old.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:

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I have a history of stroke or heart disease.

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I am either younger than 18 or older than 45.

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I have experienced chest pain or shortness of breath in the last month.

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I am not taking any medications that affect CYP2C19 enzyme activity.

Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ 2 hours

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~2 hours

This trial's timeline: 3 weeks for screening, Varies for treatment, and 2 hours for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.

Primary study objectives

Breath limonene value in parts per billion

Awards & Highlights

No Placebo-Only Group

All patients enrolled in this study will receive some form of active treatment.

Trial Design

2Treatment groups

Experimental Treatment

Group I: Wildtype CYP2C19Experimental Treatment1 Intervention

The group of participants has been genotyped to have wild-type CYP2C19. The participants will consume 1 oz water mixed with 500mg limonene (Jarrow Formula orange peel extract) and be asked to swish 5 times and swallow. All participants will then provide breath samples over the course of 2 hours. The breath sample outcomes will be compared to those of the CYP2C19\*2 and/or CYP2C19\*3 study subjects.

Group II: CYP2C19*2 and CYP2C19*3 VariantsExperimental Treatment1 Intervention

The group of participants has been genotyped to have the CYP2C19\*2 and/or CYP2C19\*3 variant during the first part of the study. The participants will consume 1 oz water mixed with 500mg limonene (Jarrow Formula orange peel extract) and be asked to swish 5 times and swallow. All participants will then provide breath samples over the course of 2 hours. The breath sample outcomes will be compared to those of the wild-type CYP2C19 study subjects.

0 / 5Eligibility criteria met

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.

Mechanism Of Action

Side Effect Profile

Prior Approvals

Other Research

CYP2C19 genetic variants affect the metabolism of various drugs, leading to differences in drug efficacy and safety among individuals. Treatments for conditions influenced by CYP2C19 activity often involve medications that are metabolized by this enzyme, such as certain antidepressants, proton pump inhibitors, and antiplatelet agents. The mechanisms of action for these treatments typically involve the modulation of neurotransmitter levels, reduction of stomach acid production, or inhibition of platelet aggregation. Understanding these mechanisms is crucial for patients with CYP2C19 genetic variants because it helps in tailoring medication choices and dosages to optimize therapeutic outcomes and minimize adverse effects. The trial measuring limonene metabolism aims to develop a non-invasive screening tool to identify these genetic variants, potentially allowing for more personalized and effective treatment plans.

Comprehensive overview of the pharmacogenetic diversity in Ashkenazi Jews.