Transporter Mediated Uptake of Montelukast
Public ClinicalTrials.gov record NCT00513760. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
Characterization of Transporter Mediated Uptake of Montelukast in Humans
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
Leukotriene receptor antagonists (LTRAs) are frequently prescribed to reduce the symptoms associated with asthma. Singulair, manufactured by Merck, is a popular LTRA, however its effectiveness varies greatly between individuals. We are interested in understanding why the effectiveness of Singulair varies so greatly. For an oral drug such as Singulair to be effective, the body must efficiently absorb it. We have found that blood levels of Singulair vary greatly between individuals, and we think that this variability is responsible for variability in response. Drug absorption occurs primarily in the intestine. Due to differences in the chemical properties of drugs, some drugs can be absorbed easily while other drugs require help from special proteins produced by the cells that line the intestine. These proteins, or transporters act like turnstiles to allow drugs to move from the intestine to the bloodstream and are known to be inhibited by components of citrus juice. The activity of a transporter can be influenced by individual genetic variability. We think that Singulair requires help from a transport protein to be absorbed and that genetic variability in this transporter leads to variability in the blood level of Singulair. In this proposal we will use citrus juice (grapefruit and orange) to inhibit intestinal membrane transport proteins and show that Singulair requires these transporters to be efficiently absorbed. Eventually, what we learn from this work will allow doctors to quickly test individuals with asthma to determine how well they will absorb Singulair and possibly other LTRAs. Knowing this will allow the doctor to adjust the drug treatment on an individual basis to maximize benefit in the treatment of asthma.
Study identification
- NCT ID
- NCT00513760
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Not applicable
- Enrollment
- 27 participants
Conditions and interventions
Conditions
Interventions
- Grapefruit juice Dietary Supplement
- Orange Juice Dietary Supplement
- Gatorade Dietary Supplement
Dietary Supplement
Eligibility (public fields only)
- Age range
- 15 Years to 18 Years
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- May 31, 2007
- Primary completion
- Aug 31, 2014
- Completion
- Nov 30, 2014
- Last update posted
- Feb 9, 2025
2007 – 2014
United States locations
- U.S. sites
- 1
- U.S. states
- 1
- U.S. cities
- 1
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Nemours Children's Clinic | Jacksonville | Florida | 32207 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT00513760, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Feb 9, 2025 · Synced Sep 8, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT00513760 live on ClinicalTrials.gov.