Biosynthesis of PGD2 in Vivo (Niacin)
We would like to see if aspirin could block niacin-induced flushing by analyzing blood and urine after taking aspirin.
Phase I: 5 days of 81 mg aspirin/placebo followed by 600 mg Niacin, 2 week washout and 5 days taking the alternate. The order in which this is given will be randomized or assigned by chance.
Phase II: One study week consisting of 5 days of taking 81 mg Aspirin, taken once daily, followed by a single dose of 600 mg Niacin on day 6.
Phase III: 5 days taking 81 mg Aspirin/placebo, 10 day washout in between.
Phase IV: Use of extended release niacin instead of instant release.
Phase V: A Celebrex study is necessary to explore the contribution of Cox-2 to niacin induced flushing.
|Healthy Volunteer||Dietary Supplement: 5 days of placebo followed by 600mg niacin Dietary Supplement: aspirin first Drug: 81 mg Aspirin Dietary Supplement: Niaspan Drug: Celebrex and niacin||Phase 4|
|Study Design:||Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Prevention
|Official Title:||A Pilot Study to Measure Plasma and Urinary Prostaglandin D2 Metabolites Evoked by Niacin|
- Area under the urinary prostaglandins concentration versus time curve (AUC) in response to niacin and aspirin [ Time Frame: -2-0, 0-2, 2-4, 4-6, 6-12 and 12-24 hours pre or post niacin ]Area under the urinary prostaglandins concentration versus time curve (AUC) in response to niacin with or without pretreatment of aspirin will be studied. Area under the urinary prostaglandins concentration versus time curve (AUC) in response to aspirin will also be studied.
- Area under the flushing response versus time curve (AUC) in response to niacin [ Time Frame: 5 mins before niacin to 6 hours after niacin administertion (continuously) ]Area under the flushing response versus time curve (AUC) in response to niacin with or without pretreatment of aspirin will be studied.
|Study Start Date:||July 2007|
|Study Completion Date:||January 2012|
|Primary Completion Date:||January 2012 (Final data collection date for primary outcome measure)|
Placebo Comparator: Phase I, Period B
Period B: 5 days of placebo, followed by a single dose of 600mg niacin.
Dietary Supplement: 5 days of placebo followed by 600mg niacin
600 mg niacin
Other Name: Niaspan
|Placebo Comparator: sugar pill||
Dietary Supplement: aspirin first
5 days taking 81 mg Aspirin followed by a single dose of 600 mg Niacin
Placebo Comparator: low dose aspirin or placebo
5 days taking either 81 mg aspirin/placebo with at least 10 day washout in between.
Drug: 81 mg Aspirin
5 days taking 81 mg Aspirin
|Active Comparator: Single dose 2 gms Niaspan for 8 days||
Dietary Supplement: Niaspan
Other Name: niacin
Placebo Comparator: Celebrex / Placebo
Celebrex 200 mg/Placebo taken for 5 days, two times daily, followed by single dose of 600 mg niacin on day five. At least 10 days in between each dosing period.
Drug: Celebrex and niacin
Data will be handled exactly like phase 1.
Other Name: niacin
The purpose of this study is to look at the roles of various blood cells and their contributions of different prostaglandins. The intention is that by better understanding these prostaglandins and various metabolites, it will provide insights into their roles in the cardiovascular system.
Prostaglandins and metabolites are naturally occurring substances found in the blood and urine which can act as markers which can be quantified and studied as we will be doing in this study. Flushing response to niacin will also be assessed by laser doppler measuring blood flow of the facial skin.
Untransformed and transformed data will be subjected to exploratory analysis of variance appropriated for a three factor design with one two period crossover factor and two non-repeated factors. Additionally, volunteer's test(s) for paired observations will characterize the magnitude of the niacin effect on the response variables within selected time points.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01275300
|United States, Pennsylvania|
|University of Pennsylvania Hospital|
|Phila., Pennsylvania, United States, 19104|