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NCT00644605 · ClinicalTrials.gov registry record · Phase 3
A Study to Assess the Efficacy and Safety of 20, 40, and 80mg of Sildenafil Three Times a Day in the Treatment of Pulmonary Arterial Hypertension
A Phase 3 study, sponsored by Pfizer's Upjohn has merged with Mylan to form Viatris.
- Completed
- Registry status
- Phase 3
- Development phase
- 275
- Enrollment target
NCT00644605: Completed Phase 3 study, sponsored by Pfizer's Upjohn has merged with Mylan to form Viatris.
NCT00644605 is a Phase 3 study that has completed, run by Pfizer's Upjohn has merged with Mylan to form Viatris. The registered enrollment target is 275 participants, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (64% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00644605, a Phase 3 study, has completed, sponsored by Pfizer's Upjohn has merged with Mylan to form Viatris.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 275 participants
- Enrollment target
Study Summary
To evaluate the effect of three doses of oral sildenafil (20, 40 and 80 mg three times a day \[TID\]) on exercise capacity, as measured by the 6-Minute Walk test, as well as the safety and tolerability, after 12 weeks of treatment in subjects with pulmonary arterial hypertension who are aged 18 years and over. To investigate the plasma concentration-effect relationship and to determine the population pharmacokinetic (PK) parameters.
Interventions
- DRUG placebo
- DRUG sildenafil
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 275 participants |
| Start Date | 2002-10 |
| Est. Completion | 2003-11 |
| Phase | Phase 3 |
What the finished NCT00644605 record still lists
NCT00644605 is an interventional study that assigns participants to a tested intervention. The registered 275 participants enrollment target is mid-sized for trials with a published cap, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (64% lower).
The record links to 0 conditions, and to 2 interventions - of which placebo is the first listed.
NCT00644605 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00644605 about?
NCT00644605 is a clinical study titled "A Study to Assess the Efficacy and Safety of 20, 40, and 80mg of Sildenafil Three Times a Day in the Treatment of Pulmonary Arterial Hypertension". To evaluate the effect of three doses of oral sildenafil (20, 40 and 80 mg three times a day \[TID\]) on exercise capacity, as measured by the 6-Minute Walk test, as well as the safety and tolerability, after 12 weeks of treatment in subjects with pulmonary arterial hypertension who are aged 18 year...
What is the current status of trial NCT00644605?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 275 participants. The study started on 2002-10. Estimated completion is 2003-11.
What interventions are being tested in trial NCT00644605?
The interventions under investigation include: placebo (DRUG), sildenafil (DRUG).
Who is sponsoring clinical trial NCT00644605?
This trial is sponsored by Pfizer's Upjohn has merged with Mylan to form Viatris, which has 158 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00644605's enrollment target sits among peer trials
275 1206th of 2000 higher than 794 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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