An interventional study of Aspirin and Placebo in Hyperlipidemia, sponsored by University of Pennsylvania. Completed at 1 site in United States. Open to participants aged 18 Years to 70 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-02-09.
Sponsored by University of Pennsylvania · Not applicable, Interventional, and Basic science
The investigator would like to see if aspirin could block niacin-induced flushing by analyzing blood and urine after taking aspirin.
Phase I: Subjects were assigned to either placebo or aspirin groups. They were given 5 days of 81 mg aspirin or placebo. On day 5, they were given a single dose of niacin (600 mg) administered 30 minutes after the last dose of aspirin or placebo. The same subjects came back for cross-over study and were assigned to a different group. There was a 2-week washout period between each treatment. Urine was collected sequentially for analysis
Phase II: The same study subjects come back for an open label one week study. They were given 5 days of taking 81 mg Aspirin, taken once daily, followed by a single dose of 600 mg Niacin on day 6. Urine was collected sequentially for analysis
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.
821 studies on the registry are indexed under Hyperlipidemias; 105 are open to participants now.
This study's enrollment of 9 is below the median of 87 across 691 interventional studies indexed under Hyperlipidemias.
Browse Hyperlipidemias studies →University of Pennsylvania is the lead sponsor of 1,635 studies on the registry; 239 are open to participants now.
Of its 154 completed or terminated interventional studies of FDA-regulated products, 104 (68%) have results posted.
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age between 18-70
Exclusion Criteria:
Subjects were given 5 days of placebo. On day 5, they were given a single dose of niacin (600 mg) administered 30 minutes after the last dose of placebo. Urine was collected sequentially for analysis. The same subjects came back for cross-over study and were assigned to Aspirin group. There was a 2-week washout period between each treatment.
Drug: Placebo · Drug: Niacin
Subjects were given 5 days of 81 mg aspirin. On day 5, they were given a single dose of niacin (600 mg) administered 30 minutes after the last dose of aspirin or placebo. Urine was collected sequentially for analysis.
Drug: Aspirin · Drug: Niacin
In phase II study, subjects were given 5 days of 81 mg aspirin. On day 6, they were given a single dose of niacin (600 mg) administered 24 hours after the last dose of aspirin. Urine was collected sequentially for analysis
Drug: Aspirin · Drug: Niacin
Also known as: Aspirin 81 mg
Also known as: Niacin 600 mg
Percentage Change of Area Under Curve for the Urinary Prostaglandins Concentration Versus Time Curve (AUC) in Response to Aspirin or Placebo
Percentage change of area under the urinary prostaglandins concentration versus time curve (AUC) in response to niacin with or without pretreatment of aspirin was studied. This outcome measures whether aspirin instead of placebo will impact the subjects' response to niacin. The area was normalized by percentile.
Time frame: -2-0, 0-2, 2-4, 4-6, 6-12 and 12-24 hours pre or post niacin
| Milestone | "Placebo+Niacin First, Then Aspirin+Niacin | Aspirin+Niacin First, Then Placebo+Niacin |
|---|---|---|
| Started | 5 | 4 |
| Completed | 5 | 4 |
| Not completed | 0 | 0 |
| Milestone | "Placebo+Niacin First, Then Aspirin+Niacin | Aspirin+Niacin First, Then Placebo+Niacin |
|---|---|---|
| Started | 5 | 4 |
| Completed | 5 | 4 |
| Not completed | 0 | 0 |
| Milestone | "Placebo+Niacin First, Then Aspirin+Niacin | Aspirin+Niacin First, Then Placebo+Niacin |
|---|---|---|
| Started | 5 | 4 |
| Completed | 5 | 4 |
| Not completed | 0 | 0 |
| Milestone | "Placebo+Niacin First, Then Aspirin+Niacin | Aspirin+Niacin First, Then Placebo+Niacin |
|---|---|---|
| Started | 5 | 4 |
| Completed | 5 | 4 |
| Not completed | 0 | 0 |
| Milestone | "Placebo+Niacin First, Then Aspirin+Niacin | Aspirin+Niacin First, Then Placebo+Niacin |
|---|---|---|
| Started | 5 | 4 |
| Completed | 5 | 4 |
| Not completed | 0 | 0 |
Percentage change of area under the urinary prostaglandins concentration versus time curve (AUC) in response to niacin with or without pretreatment of aspirin was studied. This outcome measures whether aspirin instead of placebo will impact the subjects' response to niacin. The area was normalized by percentile.
| Percentage change of area under curve | Placebo | Aspirin |
|---|---|---|
| Percentage Change of Area Under Curve for the Urinary Prostaglandins Concentration Versus Time Curve (AUC) in Response to Aspirin or Placebo | 95 (93 to 97) | 43 (38 to 48) |
Collected over 8 weeks. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| P1: Placebo/Aspirin Followed by Niacin | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| P2: Aspirin and Niacin | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| Age, Categorical(Participants) | All Study Participants |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 9 |
| >=65 years | 0 |
| Age, Continuous(years) | All Study Participants |
|---|---|
| Mean | 34 ± 3 |
| Sex: Female, Male(Participants) | All Study Participants |
|---|---|
| Female | 4 |
| Male | 5 |
| Region of Enrollment(participants) | All Study Participants |
|---|---|
| United States | 9 |
This study is completed, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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