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NCT00492531 · ClinicalTrials.gov registry record · Phase 2
Sildenafil Therapy for Pulmonary Hypertension and Sickle Cell Disease
A Phase 2 study, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
- Terminated
- Registry status
- Phase 2
- Development phase
- 74
- Enrollment target
NCT00492531: Clinical Trial Phase 2 study, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
NCT00492531 is a Phase 2 study that was terminated before completion, run by National Heart, Lung, and Blood Institute (NHLBI). The registered enrollment target is 74 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (44% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00492531, a Phase 2 study, was terminated before completion, sponsored by National Heart, Lung, and Blood Institute (NHLBI).
- TERMINATED
- Registry status
- Phase 2
- Development phase
- 74 participants
- Enrollment target
Study Summary
This study will examine whether the drug sildenafil can lower blood pressure in the pulmonary artery (the blood vessel that leads from the heart to the lungs) in patients with sickle cell disease and pulmonary hypertension (high blood pressure in the lungs). It will see if this treatment can reduce disease complications, such as shortness of breath, pain crisis, pneumonia, and increase survival. Patients 12 years of age and older with sickle cell disease and pulmonary hypertension may be eligible for this study. Participants are randomly assigned to receive sildenafil or placebo (sugar pill) for 16 weeks. Before starting treatment, patients have baseline studies, including a pregnancy test for females of childbearing age; a chest x-ray; pulmonary function tests to measure how much air the patient can breathe in and out; an echocardiogram (heart ultrasound); a 6-minute walk test to measure exercise capacity; a quality-of-life assessment and a pain inventory. Patients with moderate to severe pulmonary hypertension undergo heart catheterization to evaluate the severity of hypertension before beginning sildenafil therapy. During treatment, patients are monitored with the following: * Blood tests: weeks 6, 10 and 16. * Echocardiogram: weeks 6 and 16. * 6-minute walk test: weeks 6, 10 and 16. * Measurements of weight, blood pressure and heart rate: weeks 6, 10 and 16. * Pregnancy test for women of childbearing age: weeks 6, 10 and 16. * Pain questionnaire once a day for a week: weeks 6 and 1.0 * Quality-of-life questionnaire: week 16. * Heart catheterization: week 16 for patients with moderate to severe hypertension. At the end of the 16-week period, patients may opt to continue to receive sildenafil and monitoring in an open-label phase of the study for up to 1 year.
Primary Outcome
The primary outcome measure was change in exercise capacity assessed by 6 minute walk distance in meters from baseline to 16 weeks. Subjects without a week 16 assessment had their last observation carried forward.
Interventions
- DRUG Placebo
- DRUG Sildenafil
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 74 participants |
| Start Date | 2007-06 |
| Est. Completion | 2009-10 |
| Phase | Phase 2 |
Why NCT00492531 stopped before completion
NCT00492531 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 74 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (44% lower).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT00492531 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00492531 about?
NCT00492531 is a clinical study titled "Sildenafil Therapy for Pulmonary Hypertension and Sickle Cell Disease". This study will examine whether the drug sildenafil can lower blood pressure in the pulmonary artery (the blood vessel that leads from the heart to the lungs) in patients with sickle cell disease and pulmonary hypertension (high blood pressure in the lungs). It will see if this treatment can reduce ...
What is the current status of trial NCT00492531?
This trial is currently terminated. It is a Phase 2 study. The enrollment target is 74 participants. The study started on 2007-06. Estimated completion is 2009-10.
What interventions are being tested in trial NCT00492531?
The interventions under investigation include: Placebo (DRUG), Sildenafil (DRUG).
Who is sponsoring clinical trial NCT00492531?
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 NCT00492531's enrollment target sits among peer trials
74 920th of 2000 higher than 1,077 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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