NCT05999240

Pimavanserin for Rigid-compulsive Symptoms in Autism Spectrum Disorder

A Target Engagement Study of Pimavanserin for Behavioral Inflexibility With Open Label Trial for Rigid Rigid-compulsive Behavior in Adolescents and Adults With Autism

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: New York State Psychiatric Institute · Academic / Other
• Sex: All
• Age: 12 Years – 40 Years
• Healthy volunteers: Not accepted

Summary

This Phase 2 study examines the safety, tolerability, and preliminary efficacy of pimavanserin in individuals with Autism Spectrum Disorder. Male or female participants aged 12 to 40 years of age will be randomized to receive single doses of either placebo or pimavanserin in this randomized, placebo-controlled, cross-over designed study, followed by open label extension.

Detailed description

The goal of this clinical trial is to learn the safety, tolerability and to assess pimavanserin for effects on behavioral rigidity and rigid-compulsive behavior in adolescents and adults with Autism Spectrum Disorder. Participants who meet protocol criteria will be randomly assigned to receive either pimavanserin or placebo in a 1:1 ratio in the Treatment Period. After completing the second experimental day of the cross-over trial, participants will immediately enter the Open-Label Trial, where they will take pimavanserin 34 mg for six weeks total. There will be 2 recruiting sites with a total sample of 30 participants. Blinding will be maintained by using identical tablets containing either Pimavanserin or placebo.

Conditions

• Autism Spectrum Disorder

Interventions

Type	Name	Description
DRUG	Pimavanserin Tartrate 34 Mg ORAL CAPSULE [NUPLAZID]	Participants will be randomized to take a single dose of either pimavanserin 34 mg or placebo at Visit 2.
DRUG	Placebo	Placebo for Pimavanserin Tartrate 34 Mg ORAL CAPSILE \[NUPLAZID\]

Timeline

• Start date: 2025-10-01
• Primary completion: 2026-12-31
• Completion: 2026-12-31
• First posted: 2023-08-21
• Last updated: 2026-04-01

Locations

2 sites across 1 country: United States

Regulatory

• FDA-regulated drug study