A PET Study Following a Single Oral Dose of ITI-333 in Healthy Subjects

An Open-label, Positron Emission Tomography (PET) Study to Evaluate Brain Receptor Occupancy, Safety, Tolerability, and Pharmacokinetics After Single Oral Doses of ITI-333 in Healthy Subjects

This is an open-label, single-dose study of up to 4 dose levels of ITI-333 in healthy male and female subjects. Each cohort will enroll 6 subjects. Subjects will have a baseline PET/CT scan and a postdose PET/CT scan using [14C]-MDL100907 to characterize 5-HT2A receptor occupancy

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Drug: ITI-333

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Creve Coeur, Missouri, United States, 63141
      • Clinical Site 2
    • St Louis, Missouri, United States, 63110
      • Clinical Site 1

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy male and female subjects between 18 and 45 years old (inclusive);
• BMI inclusive of 18.0-32.0 kg/m2 at screening and a minimum weight of 50 kg;
• Willing to be confined to the clinical research unit for the duration of the inpatient period of the study;

Exclusion Criteria:

• Clinically significant abnormality within 2 years of Screening that in the Investigator's opinion may place the subject at risk or interfere with study outcome variables; this includes, but is not limited to, history of or current cardiac, hepatic, renal, neurologic, gastrointestinal (including history of gastric bypass), pulmonary, endocrinologic, hematologic, or immunologic disease or history of malignancy;
• Clinically significant abnormal findings in vital sign assessments, including blood oxygen saturation (SpO2) < 96% and respiratory rate < 12 breaths per min;
• History of psychiatric condition that in the Investigator's opinion may be detrimental to participation in the study;
• Any condition which would preclude MRI or PET/CT examination (eg, implanted metal, claustrophobia, unable to fit in PET/CT or MRI scanners).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort A1: ITI-333 2.25 mg	Drug: ITI-333; ITI-333 oral solution
Experimental: Cohort A2: ITI-333 dose to be determined based on Cohort A1	Drug: ITI-333; ITI-333 oral solution
Experimental: Cohort A3: ITI-333 dose to be determined based on Cohort A1 and A2	Drug: ITI-333; ITI-333 oral solution
Experimental: Cohort A4: ITI-333 dose to be determined based on Cohort A1, A2 and A3	Drug: ITI-333; ITI-333 oral solution

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pharmacodynamics: 5-HT2A receptor occupancy (RO) using [11C]-MDL100907		baseline 90-minute PET scan between Day -10 and Day -1, and a 90-minute PET scan starting at approximately 1 hour postdose
Pharmacokinetics: AUC0-t	Area under the plasma concentration time curve from time zero to the last measurable of concentration of ITI-333	predose and multiple timepoints up to 24 hours postdose
Pharmacokinetics: Cmax	Maximum observed plasma concentration	predose and multiple timepoints up to 24 hours postdose
Pharmacokinetics: Tmax	Time to reach maximum observed plasma concentration	predose and multiple timepoints up to 24 hours postdose

Secondary Outcome Measures

Outcome Measure	Time Frame
Percentage of subjects with treatment-emergent adverse events	up to 30 days after last dose
Change from baseline in systolic and diastolic blood pressure	Up to Day 7
Change from baseline in ECG QT interval	Up to Day 7
Change from baseline in aspartate aminotransferase	Up to Day 7
Change from baseline in alanine aminotransferase	Up to Day 7

Collaborators and Investigators

• Sponsor: Intra-Cellular Therapies, Inc.
• Collaborators: National Institute on Drug Abuse (NIDA)

Study record dates

Study Major Dates

• Study Start (Actual): July 26, 2022
• Primary Completion (Actual): May 3, 2023
• Study Completion (Actual): May 3, 2023

Study Registration Dates

• First Submitted: July 20, 2022
• First Submitted That Met QC Criteria: July 20, 2022
• First Posted (Actual): July 22, 2022

Study Record Updates

• Last Update Posted (Estimated): September 10, 2025
• Last Update Submitted That Met QC Criteria: September 3, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: ITI-333-003

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No