Extension Study of Pimavanserin in Irritability Associated With Autism Spectrum Disorder

Acadia Pharmaceuticals

Status and phase: Enrolling; Phase 3; Phase 2

Conditions: Irritability Associated With Autism Spectrum Disorder

Treatments: Drug: Pimavanserin

Study type: Interventional

Funder types: Industry

Identifiers

NCT05555615

ACP-103-070

Details and patient eligibility

About

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).

Full description

This study will be conducted as a 52-week, open-label extension study of the antecedent double-blind study to determine the long-term safety and tolerability of pimavanserin for the treatment of irritability associated with ASD in children and adolescents (5 through 17 years old at the time of enrolling into the antecedent double-blind study).

Enrollment: 228 estimated patients

Sex: All

Ages: 5 to 18 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Has completed the treatment period of study ACP-103-069
• Informed consent prior to the conduct of any study procedures
• Continues to be both clinically stable and not at imminent risk of suicide or injury to self, others, or property
• Continues to be medically stable at enrollment
• For female patients only: unable to become pregnant or agree to use a highly effective non-hormonal method of contraception. Females of childbearing potential must have a negative pregnancy test

Exclusion criteria

• Patient or parent/legally accepted representative is judged by the Investigator to be inappropriate for the study
• Requires treatment with a medication prohibited by the protocol, including concomitant psychotropic drugs targeting irritability, including those used off-label (clonidine, guanfacine, and propranolol; lithium, valproate), medications that prolong the QT interval; and strong cytochrome P450 (CYP) 3A4 enzyme (CYP3A4) inhibitors and inducers
• At a significant risk of suicide, or is a danger to self or others
• At risk of significant violent behavior to the extent that participation would pose an undue risk to other patients, caregivers, or others
• Positive urine drug test
• Serious and/or unstable psychiatric, neurologic, cardiovascular, respiratory, gastrointestinal, renal, hepatic, hematologic, or other medical disorder, including cancer or malignancies
• Any change in medical or treatment status that may increase the risk associated with taking pimavanserin, would interfere with safety assessments, or would confound the interpretation of study results
• Clinically significant abnormal ECG of protocol-defined cardiac conduction abnormalities
• Weight <15 kg
• Additional inclusion/exclusion criteria apply. Subjects will be evaluated at screening to ensure that all criteria for study participation are met.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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228 participants in 1 patient group

Pimavanserin

Experimental group

Description:

Pimavanserin once daily. All patients will receive the pimavanserin low dose (patients aged 5 to 12 years: 10 mg/day pimavanserin; patients aged 13 to 17 years: 20 mg/day) the first 2 weeks of the study. Thereafter, the dose may be increased to the high dose (5 to 12 years: 20 mg/day; 13 to 17 years: 34 mg/day) based on the Investigator's assessment of clinical response. After Week 2 and up to Week 20, dose adjustments are allowed at any clinic visit based on the Investigator's assessment of clinical response and tolerability. No further dose adjustments are allowed after Week 20.

Treatment:

Drug: Pimavanserin