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NCT05555615 · ClinicalTrials.gov registry record · Phase 2
Extension Study of Pimavanserin in Irritability Associated With Autism Spectrum Disorder
A Phase 2 study, sponsored by ACADIA Pharmaceuticals.
- Terminated
- Registry status
- Phase 2
- Development phase
- 209
- Enrollment target
NCT05555615: Clinical Trial Phase 2 study, sponsored by ACADIA Pharmaceuticals.
NCT05555615 is a Phase 2 study that was terminated before completion, run by ACADIA Pharmaceuticals. The registered enrollment target is 209 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (57% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05555615, a Phase 2 study, was terminated before completion, sponsored by ACADIA Pharmaceuticals.
- TERMINATED
- Registry status
- Phase 2
- Development phase
- 209 participants
- Enrollment target
Study Summary
52-week, open-label extension study of double-blind study ACP-103-069 to determine the long-term safety and tolerability of pimavanserin for the treatment of irritability associated with ASD in children and adolescents (aged 5 to 17 years). ACP-103-069 is a 6-week, randomized, double-blind, fixed-dose, placebo controlled, parallel group study of pimavanserin in children and adolescents with irritability associated with autism spectrum disorder (ASD).
Primary Outcome
Number (%) of patients with treatment emergent adverse events
Interventions
- DRUG Pimavanserin
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 209 participants |
| Start Date | 2022-11-02 |
| Est. Completion | 2025-02-14 |
| Phase | Phase 2 |
Why NCT05555615 stopped before completion
NCT05555615 is an interventional study that assigns participants to a tested intervention. The registered 209 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (57% higher).
The record links to 0 conditions, and to 1 intervention - of which Pimavanserin is the first listed.
NCT05555615 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05555615 about?
NCT05555615 is a clinical study titled "Extension Study of Pimavanserin in Irritability Associated With Autism Spectrum Disorder". 52-week, open-label extension study of double-blind study ACP-103-069 to determine the long-term safety and tolerability of pimavanserin for the treatment of irritability associated with ASD in children and adolescents (aged 5 to 17 years). ACP-103-069 is a 6-week, randomized, double-blind, fixed-d...
What is the current status of trial NCT05555615?
This trial is currently terminated. It is a Phase 2 study. The enrollment target is 209 participants. The study started on 2022-11-02. Estimated completion is 2025-02-14.
What interventions are being tested in trial NCT05555615?
The interventions under investigation include: Pimavanserin (DRUG).
Who is sponsoring clinical trial NCT05555615?
This trial is sponsored by ACADIA Pharmaceuticals, which has 35 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05555615's enrollment target sits among peer trials
209 294th of 2000 higher than 1,707 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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