Clinical trial NCT00817999: The Impact of Grapefruit Juice on the Response to Clopidogrel
Official title: The Impact of Grapefruit Juice on the Response to a Loading Dose and Maintenance Dose of Clopidogrel in Healthy Volunteers
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Healthy
Keywords: Platelet Aggregation Inhibition
Lead sponsor: Creighton University
Sponsor class: OTHER
First posted: 2009-01-07
Enrollment: 32
Sex: ALL
Minimum age (years): 19
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: SCREENING

Brief summary: This study will measure the percentage of platelet aggregation inhibition with a loading dose of clopidogrel (300 mg) using the VerifyNow Assay System in healthy volunteers who have drank 11 oz of grapefruit juice. It will also measure the percentage of platelet aggregation inhibition with a maintenance dose of clopidogrel (75 mg/day) using the VerifyNow Assay System in healthy volunteers who have drank 11 oz grapefruit juice daily.

Detailed description: This study will examine the effect of GFJ on the loading dose (300 mg) of clopidogrel and will evaluate the effect of GFJ on the maintenance dose (75 mg/day) of clopidogrel. Subjects will be randomized to either initially receive GFJ prior to their loading dose of clopidogrel or receive GFJ prior to their second loading dose. The subjects who have been randomized to receive GFJ initially will drink two small cans (11 oz total) of regular strength GFJ in the morning, followed two hours later by a loading dose (300 mg) of clopidogrel and will then return to the clinic 6 hours after their loading dose to have their platelet inhibition measured. Subjects will have \~ 5 milliliters (1 teaspoonful) of whole blood drawn from an antecubital vein in their forearm via a 21 gauge needle attached to a blue-top plastic vacuette sodium citrate blood collection (Greiner, Monroe, NC) tube to test inhibition of platelet aggregation. After their first loading dose, a 2 week washout period will follow to allow for their platelet aggregation to return to normal. Following the washout period, the subjects will take their second loading dose of clopidogrel and again return to the clinic for platelet inhibition measurement. The same timing will be followed for the loading dose taken without prior GFJ.

During the maintenance dose phase of this study, subjects will take 75 mg/day clopidogrel for 7 days with or without GFJ. Subjects will be randomized to either GFJ during the first period or GFJ during the second period. A minimum 2 week washout period will occur between the two 7 day courses of clopidogrel. Platelet inhibition measurement will occur at the end of each 7 day period as described above.

Eligibility criteria: Inclusion Criteria:

* Ages 19-40
* Health status confirmed by medical history and physical examination and laboratory analysis

Exclusion Criteria:

* Pregnancy
* Taking routine prescription or over-the-counter prescriptions
* Taken over-the-counter analgesic/anti-inflammatory medication within two weeks of study participation
* Recently had grapefruit juice or regularly drinks grapefruit juice

Primary outcomes:
measure: % Platelet Inhibition
timeFrame: 6 hours
Secondary outcomes:
Other outcomes:
Locations:
city: Omaha
country: United States
facility: Creighton Cardiac Center
state: Nebraska
Study officials:
affiliation: Creighton Cardiac Center
name: Tammy Burns, PharmD
role: PRINCIPAL_INVESTIGATOR
References: