CompletedNCT05732194Updated Jun 9, 2026Results posted

Multiple Ascending Dose Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of ITI 333 in Healthy Volunteers

A Phase 1 interventional study of ITI-333 and Placebo in Healthy Volunteers, sponsored by Intra-Cellular Therapies, Inc.. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-09.

Sponsored by Intra-Cellular Therapies, Inc. · Phase 1, Interventional, and Treatment

Phase: Phase 1
Study type: Interventional
Enrollment: 32
Allocation: Randomized
Ages: 18 Years to 45 Years
Sex: All

Study summary

The study will be conducted as a single-center, randomized, double-blind, placebo-controlled, ascending dose study in up to 4 sequential cohorts of healthy subjects. Each cohort will enroll 8 subjects: 6 subjects will receive ITI-333 and 2 subjects will receive placebo once daily for 14 days.

Conditions studied

Healthy Volunteers

In context

Lead sponsor

Intra-Cellular Therapies, Inc. is the lead sponsor of 40 studies on the registry; 12 are open to participants now.

Of its 23 completed or terminated interventional studies of FDA-regulated products, 10 (43%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years to 45 Years
Sexes eligible: All
Accepts healthy volunteers: Yes

Eligibility criteria

Key Inclusion Criteria:

Healthy male and female subjects between 18 and 45 years old (inclusive);
BMI inclusive of 18-32 kg/m2 at screening and a minimum weight of 50 kg;
Willingness to remain in the clinic for the inpatient portion of the study and return for follow-up visit(s) as required by protocol and as deemed necessary by the Investigator.

Key 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, GI, 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;
CRP, ESR, or fibrinogen that are above normal reference ranges at Screening or Day 1.

Study design

Phase: Phase 1
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Sequential assignment
Masking: Double (Participant, Investigator)
Enrollment: 32 participants (actual)

Study arms

Experimental
Cohort 1: 0.75 mg ITI-333 or placebo once daily for 14 days
Drug: ITI-333 · Other: Placebo
Experimental
Cohort 2: 1.5 mg ITI-333 or placebo once daily for 14 days
Drug: ITI-333 · Other: Placebo
Experimental
Cohort 3: 3 mg ITI-333 or placebo once daily for 14 days
Drug: ITI-333 · Other: Placebo
Experimental
Cohort 4: 6 mg ITI-333 or placebo once daily for 14 days
Drug: ITI-333 · Other: Placebo

Interventions

DrugITI-333
ITI-333 oral solution
OtherPlacebo
Matching placebo

What researchers measure

Primary outcomes

Pharmacokinetics: AUC0-tau
Area under the plasma drug concentration-time curve (AUC) from time zero to the end of dosing interval
Time frame: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Pharmacokinetics: Cmax
Maximum plasma concentration of ITI-333 over a dosing interval
Time frame: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Pharmacokinetics: Tmax
Time of maximum plasma concentration of ITI-333 over a dosing interval
Time frame: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Percentage of Subjects With Treatment-emergent Adverse Events
Time frame: up to 30 days after last dose
Change From Baseline in Systolic and Diastolic Blood Pressure
Time frame: Baseline and Day 17
Change From Baseline in SpO2
Time frame: Baseline and Day 17
Change From Baseline in ECG QTcF Interval
Time frame: Baseline and Day 17
Change From Baseline in Aspartate Aminotransferase
Time frame: Baseline and Day 17
Change From Baseline in Alanine Aminotransferase
Time frame: Baseline and Day 17

Results

Posted Mar 31, 2026

Participant flow

Participant flow — Overall Study
Milestone	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Started	6	6	6	6	8
Completed	6	6	6	5	7
Not completed	0	0	0	1	1

Outcome measures

PrimaryPharmacokinetics: AUC0-tau

Area under the plasma drug concentration-time curve (AUC) from time zero to the end of dosing interval

Time frame:: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Reported as:: Mean · h*ng/mL

Pharmacokinetics: AUC0-tau
h*ng/mL	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333
Pharmacokinetics: AUC0-tau	94.927 ± 77.467	107.30 ± 57.596	294.48 ± 161.01	1059.5 ± 185.18

PrimaryPharmacokinetics: Cmax

Maximum plasma concentration of ITI-333 over a dosing interval

Time frame:: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Reported as:: Mean · ng/mL

Pharmacokinetics: Cmax
ng/mL	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333
Pharmacokinetics: Cmax	8.810 ± 3.644	16.75 ± 6.142	41.60 ± 16.29	117.3 ± 27.13

PrimaryPharmacokinetics: Tmax

Time of maximum plasma concentration of ITI-333 over a dosing interval

Time frame:: Day 14: predose (0), 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h postdose
Reported as:: Median · h

Pharmacokinetics: Tmax
h	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333
Pharmacokinetics: Tmax	1.500 (1.00 to 1.50)	1.000 (1.00 to 1.50)	1.000 (1.00 to 2.00)	1.000 (1.00 to 1.00)

PrimaryPercentage of Subjects With Treatment-emergent Adverse Events

Time frame:: up to 30 days after last dose
Reported as:: Count of participants · Participants

Percentage of Subjects With Treatment-emergent Adverse Events
Participants	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Percentage of Subjects With Treatment-emergent Adverse Events	0	1	4	2	4

PrimaryChange From Baseline in Systolic and Diastolic Blood Pressure

Time frame:: Baseline and Day 17
Reported as:: Mean · mmHg

Change From Baseline in Systolic and Diastolic Blood Pressure
mmHg	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Systolic Blood Pressure	-2.3 ± 8.33	2.3 ± 4.93	10.7 ± 11.15	5.5 ± 5.75	3.8 ± 10.40
Diastolic Blood Pressure	-0.3 ± 8.48	0.5 ± 6.75	3.3 ± 7.55	4.0 ± 4.34	2.9 ± 6.36

PrimaryChange From Baseline in SpO2

Time frame:: Baseline and Day 17
Reported as:: Mean · % (percentage of oxygen saturation)

Change From Baseline in SpO2
% (percentage of oxygen saturation)	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Change From Baseline in SpO2	0.3 ± 0.82	1.5 ± 0.55	0.5 ± 1.05	-0.2 ± 1.33	0.6 ± 0.92

PrimaryChange From Baseline in ECG QTcF Interval

Time frame:: Baseline and Day 17
Reported as:: Mean · msec

Change From Baseline in ECG QTcF Interval
msec	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Change From Baseline in ECG QTcF Interval	-12.5 ± 8.46	-4.3 ± 9.00	-0.3 ± 23.72	-8.7 ± 9.31	-4.6 ± 14.28

PrimaryChange From Baseline in Aspartate Aminotransferase

Time frame:: Baseline and Day 17
Reported as:: Mean · U/L

Change From Baseline in Aspartate Aminotransferase
U/L	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Change From Baseline in Aspartate Aminotransferase	-0.8 ± 6.08	-1.5 ± 3.94	-3.7 ± 4.27	2.0 ± 7.48	-0.3 ± 2.12

PrimaryChange From Baseline in Alanine Aminotransferase

Time frame:: Baseline and Day 17
Reported as:: Mean · U/L

Change From Baseline in Alanine Aminotransferase
U/L	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
Change From Baseline in Alanine Aminotransferase	0.0 ± 16.61	2.8 ± 14.65	1.5 ± 15.60	4.3 ± 19.37	2.8 ± 3.41

Adverse events

Collected over Up to 30 days after the last dose. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
0.75 mg ITI-333	0/6 (0%)	0/6 (0%)	0/6 (0%)
1.5 mg ITI-333	0/6 (0%)	0/6 (0%)	1/6 (16.7%)
3 mg ITI-333	0/6 (0%)	0/6 (0%)	4/6 (66.7%)
6 mg ITI-333	0/6 (0%)	0/6 (0%)	2/6 (33.3%)
Pooled Placebo	0/8 (0%)	0/8 (0%)	4/8 (50%)

Most frequent other events

Showing 10 of 12

Most frequent other events
Event	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo
HeadacheNervous system disorders	0/6	1/6	3/6	0/6	2/8
SomnolenceNervous system disorders	0/6	0/6	1/6	0/6	0/8
Alanine aminotransferase increasedInvestigations	0/6	0/6	1/6	0/6	0/8
C-reactive protein increasedInvestigations	0/6	0/6	1/6	0/6	0/8
Back painMusculoskeletal and connective tissue disorders	0/6	0/6	0/6	1/6	1/8
RhabdomyolysisMusculoskeletal and connective tissue disorders	0/6	0/6	1/6	0/6	0/8
PruritusSkin and subcutaneous tissue disorders	0/6	0/6	0/6	1/6	0/8
Rash maculo-papularMusculoskeletal and connective tissue disorders	0/6	0/6	0/6	1/6	0/8
DizzinessNervous system disorders	0/6	0/6	0/6	0/6	1/8
Blood creatine phosphokinase increasedInvestigations	0/6	0/6	0/6	0/6	1/8

Baseline characteristics

Age, Continuous
Age, Continuous(years)	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo	Total
Mean	33.3 ± 7.66	30.3 ± 8.48	37.2 ± 7.33	28.7 ± 11.24	34.1 ± 8.95	32.8 ± 8.77

Sex: Female, Male
Sex: Female, Male(Participants)	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo	Total
Female	2	4	0	6	5	17
Male	4	2	6	0	3	15

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	0.75 mg ITI-333	1.5 mg ITI-333	3 mg ITI-333	6 mg ITI-333	Pooled Placebo	Total
American Indian or Alaska Native	0	0	0	0	0	0
Asian	0	0	0	0	0	0
Native Hawaiian or Other Pacific Islander	0	0	0	0	0	0
Black or African American	1	0	0	3	2	6
White	5	6	6	3	6	26
More than one race	0	0	0	0	0	0
Unknown or Not Reported	0	0	0	0	0	0

Study locations

1 site

Clinical Site 1
Miami, Florida 33014-3616, United States

References and documents

Study documents

Study protocol · Nov 6, 2023
Statistical analysis plan · Nov 13, 2023

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Jun 9, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT05732194
Lead sponsor: Intra-Cellular Therapies, Inc.
Collaborators: National Institute on Drug Abuse (NIDA)
Responsible party: Sponsor
First posted: Feb 16, 2023
Start date: Jan 18, 2023
Primary completion: Sep 1, 2023
Completion: Sep 1, 2023
Results posted: Mar 31, 2026
Last update: Jun 9, 2026

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.

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