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NCT00056433 · ClinicalTrials.gov registry record · Phase 1
Evaluation of Hydroxyurea Plus L-arginine or Sildenafil to Treat Sickle Cell Anemia
A Phase 1 study, sponsored by National Institutes of Health Clinical Center (CC).
- Completed
- Registry status
- Phase 1
- Development phase
- 39
- Enrollment target
NCT00056433: Completed Phase 1 study, sponsored by National Institutes of Health Clinical Center (CC).
NCT00056433 is a Phase 1 study that has completed, run by National Institutes of Health Clinical Center (CC). The registered enrollment target is 39 participants, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (35% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00056433, a Phase 1 study, has completed, sponsored by National Institutes of Health Clinical Center (CC).
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 39 participants
- Enrollment target
Study Summary
Patients with sickle cell disease have abnormal hemoglobin (the protein in red blood cells that carries oxygen to the body). This abnormality causes red blood cells to take on a sickle shape, producing disease symptoms. Fetal hemoglobin, a type of hemoglobin present in fetuses and babies, can prevent red cells from sickling. The drug hydroxyurea increases fetal hemoglobin production in patients with sickle cell disease by making a molecule called nitric oxide. The drugs L-arginine and Sildenafil (Viagra) increase the amount or the effect of nitric oxide. This study will evaluate: * The safety of giving L-arginine or Sildenafil together with hydroxyurea in patients with sickle cell disease; * The effectiveness of L-arginine plus hydroxyurea or Sildenafil plus hydroxyurea in increasing fetal hemoglobin in patients with sickle cell disease; and * The effectiveness of L-arginine plus hydroxyurea or Sildenafil and hydroxyurea in lowering blood pressure in the lungs of patients with sickle cell disease. (Pulmonary blood pressure is elevated in about one-third of patients with sickle cell disease, and this condition increases the risk of dying from the disease.) Patients with hemoglobin S-only, S-beta-thalassemia, or other sickle cell disease genotype may be eligible for this study. Before starting treatment, patients will have a complete medical history and physical examination. All patients will take hydroxyurea once a day every day by mouth for at least 2 months. They will be admitted to the NIH Clinical Center to take their first dose of hydroxyurea, and will have blood drawn through a catheter (plastic tube placed in a vein) every hour for 6 hours for tests to determine nitric oxide levels. After discharge, they will return to the clinic once every 2 weeks to check for treatment side effects and for blood tests to monitor hemoglobin and fetal hemoglobin levels. After fetal hemoglobin levels have been stable for 2 months, patients will be admitted to the Clinical Ce
Interventions
- DRUG Hydroxyurea
- DRUG L-Arginine
- DRUG Sildenafil
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 39 participants |
| Start Date | 2003-03-10 |
| Est. Completion | 2006-12-27 |
| Phase | Phase 1 |
What the finished NCT00056433 record still lists
NCT00056433 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 39 participants, a relatively small participant target, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (35% lower).
The record links to 0 conditions, and to 3 interventions - of which Hydroxyurea is the first listed.
NCT00056433 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00056433 about?
NCT00056433 is a clinical study titled "Evaluation of Hydroxyurea Plus L-arginine or Sildenafil to Treat Sickle Cell Anemia". Patients with sickle cell disease have abnormal hemoglobin (the protein in red blood cells that carries oxygen to the body). This abnormality causes red blood cells to take on a sickle shape, producing disease symptoms. Fetal hemoglobin, a type of hemoglobin present in fetuses and babies, can preven...
What is the current status of trial NCT00056433?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 39 participants. The study started on 2003-03-10. Estimated completion is 2006-12-27.
What interventions are being tested in trial NCT00056433?
The interventions under investigation include: Hydroxyurea (DRUG), L-Arginine (DRUG), Sildenafil (DRUG).
Who is sponsoring clinical trial NCT00056433?
This trial is sponsored by National Institutes of Health Clinical Center (CC), which has 338 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00056433's enrollment target sits among peer trials
39 1191st of 2000 higher than 804 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 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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