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NCT00508989 · ClinicalTrials.gov registry record · Phase 2
Niacin to Improve Blood Flow in People With Sickle Cell Disease
A Phase 2 study, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
- Completed
- Registry status
- Phase 2
- Development phase
- 30
- Enrollment target
NCT00508989: Completed Phase 2 study, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
NCT00508989 is a Phase 2 study that has completed, run by National Heart, Lung, and Blood Institute (NHLBI). The registered enrollment target is 30 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (77% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00508989, a Phase 2 study, has completed, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 30 participants
- Enrollment target
Study Summary
This study will determine whether niacin can improve blood flow in people with sickle cell disease, in which abnormal red blood cells interfere with blood flow to cause the disease symptoms. Niacin, a drug that has been used to increase HDL (good cholesterol) levels, improves blood flow in people without sickle cell disease. This study will see if it can do the same in people with the disease. Patients with sickle cell disease between 18 and 65 years of age may be eligible for this study. Candidates are screened with a medical history, physical examination, blood tests, echocardiogram and 6-minute walk test of exercise capacity. Participants have the following baseline blood flow studies: * Flow-mediated dilation (FMD): An ultrasound picture of the artery in the forearm is obtained. A blood pressure cuff is then placed on the upper arm and inflated for 5 minutes. After the pressure cuff is released, the ultrasound is repeated. * Peripheral artery tonometry (PAT): A sensor is placed on the subject s finger. The sensor puts pressure on the finger and measures blood flow. * Standard forearm blood flow test: Small tubes are placed in the artery of the forearm at the inside of the elbow. Saline is infused into one tube. Pressure cuffs are applied to the wrist and upper arm. A strain gauge (rubber band device) is placed around the forearm. When the cuffs are inflated, blood flows into the arm, stretching the strain gauge, and the flow measurement is recorded. Blood samples are collected from the tube in the artery to measure blood counts, proteins and other chemicals. At various times, small doses of the following drugs are administered through the tube in the vein: * Sodium nitroprusside causes blood vessels to dilate and increases blood flow to the heart. * Acetylcholine causes blood vessels to dilate and slows heart rate. * LNMMA decreases blood flow by blocking the production of nitric oxide. Blood flow is measured after each dose of the different drugs. T
Interventions
- DRUG Placebo
- DRUG Acetylcholine
- DRUG L-NMMA
- DRUG Niacin-ER
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 30 participants |
| Start Date | 2007-07-24 |
| Est. Completion | 2015-12-24 |
| Phase | Phase 2 |
What the finished NCT00508989 record still lists
NCT00508989 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 30 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (77% lower).
The record links to 0 conditions, and to 4 interventions - of which Placebo is the first listed.
NCT00508989 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00508989 about?
NCT00508989 is a clinical study titled "Niacin to Improve Blood Flow in People With Sickle Cell Disease". This study will determine whether niacin can improve blood flow in people with sickle cell disease, in which abnormal red blood cells interfere with blood flow to cause the disease symptoms. Niacin, a drug that has been used to increase HDL (good cholesterol) levels, improves blood flow in people wi...
What is the current status of trial NCT00508989?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 30 participants. The study started on 2007-07-24. Estimated completion is 2015-12-24.
What interventions are being tested in trial NCT00508989?
The interventions under investigation include: Placebo (DRUG), Acetylcholine (DRUG), L-NMMA (DRUG), Niacin-ER (DRUG).
Who is sponsoring clinical trial NCT00508989?
This trial is sponsored by National Heart, Lung, and Blood Institute (NHLBI), which has 501 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00508989's enrollment target sits among peer trials
30 1582nd of 2000 higher than 332 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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