NCT05999240 · New York State Psychiatric Institute
Pimavanserin for Rigid-compulsive Symptoms in Autism Spectrum Disorder
What this study is about
This Phase 2 study examines the safety, tolerability, and preliminary effectiveness of pimavanserin in individuals with Autism Spectrum Disorder.
View original scientific description
This Phase 2 study examines the safety, tolerability, and preliminary efficacy of pimavanserin in individuals with Autism Spectrum Disorder. Male or female participants aged 16 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.
Interventions
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 \[NUPLAZID\]
Primary outcome measures
Evaluate the impact of a single dose of pimavanserin 34 mg versus placebo
Time frame: Post Intervention, 30 days after study completion
Assessed using cognitive neuroscience task, comparison between pimavanserin and placebo within participants in single-dose cross-over experiment.
Evaluate pimavanserin for treatment of restricted/repetitive behavior in ASD
Time frame: 6 weeks of Open-Label treatment
Assessed using the Repetitive Behavior Scale - Revised (RBS-R) rated at baseline, 3, and 6 weeks. The RBS-R is a 44-item self-report form used to measure the wide range of repetitive behavior in children, adolescents, and adults with Autism Spectrum disorders. The scale consists of six subscales with questions related to Stereotyped Behavior, Self-injurious Behavior, Compulsive Behavior, Routine Behavior, Sameness Behavior, and Restricted Behavior rated between 0 to 3 on severity of each item.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Participant must be at least 16 years old and no greater than 40 years old.
- Participants 18 years of age or older or a legally acceptable representative must be able and willing to sign an informed consent document indicating understanding of the protocol and procedures and willingness to participate in full. For adult participants, a parent, caregiver, or other adult informant must also sign an informed consent document indicating understanding the requirements for completing their portion of the study and their willingness to participate. For a participant who is under 18 years of age, a parent or guardian must sign an informed consent document indicating understanding the protocol and procedures and willingness to participate in full. Signed assent indicating understanding and willingness to participate is required of participants under 18 years of age.
- Participant must have a diagnosis of Autism Spectrum Disorder, according to DSM-5 criteria, made by a li
Where
- Lawrence, Kansas
- White Plains, New York
Collaborators
ACADIA Pharmaceuticals Inc., University of Kansas Medical Center, Research Foundation for Mental Hygiene, Inc., Weill Medical College of Cornell University
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 1, 2026 · Source of record for eligibility and locations