The Impact of Grapefruit Juice on the Response to Clopidogrel

• Sponsor: Creighton University (Other)
• Overall Status: Completed
• CT.gov ID: NCT00817999
• Collaborator: (none)
• Enrollment: 32
• Location: 1
• Arms: 2
• Duration (Months): 31.9
• Patients Per Site Per Month: 1

Study Details

Study Description

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.

Condition or Disease	Intervention/Treatment	Phase
Healthy	Dietary Supplement: Grapefruit juice; Drug: Clopidogrel 75 mg/day; Drug: Clopidogrel 300 mg	Phase 4

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.

Study Design

• Study Type: Interventional
• Actual Enrollment: 32 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: None (Open Label)
• Primary Purpose: Screening
• Official Title: The Impact of Grapefruit Juice on the Response to a Loading Dose and Maintenance Dose of Clopidogrel in Healthy Volunteers
• Study Start Date: Nov 1, 2008
• Actual Primary Completion Date: Jul 1, 2011
• Actual Study Completion Date: Jul 1, 2011

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Loading Dose Participants received a 300 mg dose of clopidogrel with or without GFJ.	Dietary Supplement: Grapefruit juice; Participants received grapefruit juice during 1 of the 2 periods.; Drug: Clopidogrel 300 mg
Experimental: Maintenance Dose Participants received clopidogrel 75 mg/day for 7 days with or without GFJ	Dietary Supplement: Grapefruit juice; Participants received grapefruit juice during 1 of the 2 periods.; Drug: Clopidogrel 75 mg/day

Outcome Measures

Primary Outcome Measures

1. % Platelet Inhibition [6 hours]

   % platelet inhibition measured by Verify Now

Eligibility Criteria

Criteria

• Ages Eligible for Study: 19 Years to 40 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

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

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Creighton Cardiac Center	Omaha	Nebraska	United States	68131

Sponsors and Collaborators

• Creighton University

Investigators

• Principal Investigator: Tammy Burns, PharmD, Creighton Cardiac Center

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Creighton University
• ClinicalTrials.gov Identifier: NCT00817999
• Other Study ID Numbers: 08-15073
• First Posted: Jan 7, 2009
• Last Update Posted: Oct 1, 2012
• Last Verified: Aug 1, 2012

• Keywords provided by Creighton University: Platelet Aggregation Inhibition
• Additional relevant MeSH terms: Clopidogrel

Study Results

Participant Flow

Arm/Group Title	Loading Dose	Maintenance Dose
Arm/Group Description	Healthy volunteers who received a 300 mg dose of clopidogrel with or without grapefruit juice.	Healthy volunteers who received clopidogrel 75 mg/day for 7 days during each period with or without grapefruit juice.
Period Title: Grapefruit Juice
STARTED	15	17
COMPLETED	15	17
NOT COMPLETED	0	0
Period Title: Grapefruit Juice
STARTED	15	17
COMPLETED	15	17
NOT COMPLETED	0	0

Baseline Characteristics

Arm/Group Title	Loading Dose	Maintenance Dose	Total
Arm/Group Description	Total of all reporting groups
Overall Participants	15	17	32
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	15 100%	17 100%	32 100%
>=65 years	0 0%	0 0%	0 0%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	24.4 (5.9)	25.47 (5.66)	25.47 (5.66)
Sex: Female, Male (Count of Participants)
Female	10 66.7%	13 76.5%	23 71.9%
Male	5 33.3%	4 23.5%	9 28.1%
Region of Enrollment (participants) [Number]
United States	15 100%	17 100%	32 100%

Outcome Measures

1. Primary Outcome

Title	% Platelet Inhibition
Description	% platelet inhibition measured by Verify Now
Time Frame	6 hours

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Loading Dose With Grapefruit Juice	Maintenance Dose With Grapefruit Juice	Loading Dose Without Grapefruit Juice	Maintenance Dose Without Grapefruit Juice
Arm/Group Description
Measure Participants	15	17	15	17
Mean (Standard Deviation) [percentage of platelet inhibition]	23.4 (14.2)	24.6 (24.2)	41.2 (19.1)	59 (22.5)

Adverse Events

Arm/Group Title	Loading Dose		Maintenance Dose
Arm/Group Description
All Cause Mortality
	Loading Dose		Maintenance Dose
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	/ (NaN)		/ (NaN)
Serious Adverse Events
	Loading Dose		Maintenance Dose
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/15 (0%)		0/17 (0%)
Other (Not Including Serious) Adverse Events
	Loading Dose		Maintenance Dose
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/15 (0%)		0/17 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.