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NCT00455715 · ClinicalTrials.gov registry record · Phase 4
A Placebo-Controlled Single-Dose Trial of Sildenafil in Schizophrenia
A Phase 4 study, sponsored by Massachusetts General Hospital.
- Completed
- Registry status
- Phase 4
- Development phase
- 18
- Enrollment target
NCT00455715: Completed Phase 4 study, sponsored by Massachusetts General Hospital.
NCT00455715 is a Phase 4 study that has completed, run by Massachusetts General Hospital. The registered enrollment target is 18 participants, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (97% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00455715, a Phase 4 study, has completed, sponsored by Massachusetts General Hospital.
- COMPLETED
- Registry status
- Phase 4
- Development phase
- 18 participants
- Enrollment target
Study Summary
The study is a double-blind, placebo-controlled, random-order, single-dose crossover trial of sildenafil 50 \& 100 mg added to stable antipsychotic treatment in schizophrenia patients to assess whether this PDE5 inhibitor improves cognitive functioning (including verbal memory, fluency, attention, spatial memory, motor speed, and executive function) and clinical symptoms (psychotic, negative, mood symptoms, and self-reports of side-effects).
Interventions
- DRUG Sildenafil
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 18 participants |
| Start Date | 2006-02 |
| Est. Completion | 2008-09 |
| Phase | Phase 4 |
What the finished NCT00455715 record still lists
NCT00455715 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 18 participants, a relatively small participant target, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (97% lower).
The record links to 0 conditions, and to 1 intervention - of which Sildenafil is the first listed.
NCT00455715 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00455715 about?
NCT00455715 is a clinical study titled "A Placebo-Controlled Single-Dose Trial of Sildenafil in Schizophrenia". The study is a double-blind, placebo-controlled, random-order, single-dose crossover trial of sildenafil 50 \& 100 mg added to stable antipsychotic treatment in schizophrenia patients to assess whether this PDE5 inhibitor improves cognitive functioning (including verbal memory, fluency, attention, s...
What is the current status of trial NCT00455715?
This trial is currently completed. It is a Phase 4 study. The enrollment target is 18 participants. The study started on 2006-02. Estimated completion is 2008-09.
What interventions are being tested in trial NCT00455715?
The interventions under investigation include: Sildenafil (DRUG).
Who is sponsoring clinical trial NCT00455715?
This trial is sponsored by Massachusetts General Hospital, which has 2,032 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00455715's enrollment target sits among peer trials
18 1842nd of 2000 higher than 147 of 2,000 other Phase 4 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 4 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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