A Clinical Trial That Will Study the Efficacy and Safety of an Investigational Drug in Acutely Psychotic People With Schizophrenia

Recruitment Status
COMPLETED - HAS RESULTS
(See Contacts and Locations)Verified April 2026 by Otsuka Pharmaceutical Development & Commercialization, Inc.
Sponsor
Otsuka Pharmaceutical Development & Commercialization, Inc.
Information Provided by (Responsible Party)
Otsuka Pharmaceutical Development & Commercialization, Inc.
Clinicaltrials.gov Identifier
NCT04092686
Other Study ID Numbers:
SEP361-302
First Submitted
September 12, 2019
First Posted
September 16, 2019
Results First Posted
May 25, 2026
Last Update Posted
June 17, 2026
Last Verified
April 2026

ClinicalTrials.gov processed this data on May 2026. Link to the current ClinicalTrials.gov record .

History of Changes

Study Details

Study Description

This is a multicenter, randomized, double-blind, parallel-group, fixed-dosed study evaluating the efficacy and safety of two doses of SEP-363856 (75 and 100 mg/day) versus placebo over a 6-week Treatment Period in acutely psychotic participants with schizophrenia. This study is projected to randomize approximately 462 participants to 3 treatment groups (SEP-363856 75 mg/day, SEP-363856 100 mg/day, or placebo) in a 1:1:1 ratio. Treatment assignment will be stratified by country. Study drug will be taken once a day and may be taken with or without food.

This study is designed to test the hypotheses that treatment with SEP-363856 in adult participants with schizophrenia will result in significantly greater reduction (i.e. improvement) in PANSS total score and CGI-S score at Week 6 from Baseline when compared to placebo. The overall Type I error is controlled for two hierarchical families of hypotheses. The first family includes hypotheses about the testing of change from Baseline in PANSS total score at Week 6 between each of the SEP-363856 dose levels vs. placebo. The second family of hypotheses are about the testing of change from Baseline in CGI-S score at Week 6 between each of the SEP-363856 dose levels vs. placebo.

Sumitomo Pharma America Inc. was the former Sponsor and conducted this study. Sumitomo was responsible for analysis and clinical study report (CSR) completion. Otsuka took over study after IND was transferred and is concluding activities with registry postings.

Condition or DiseaseIntervention/Treatment
Schizophrenia
Drug: SEP-363856 75mgDrug: SEP-363856 100mgDrug: Placebo

Study Design

Study TypeInterventional
Actual Enrollment464 participants
Design AllocationRandomized
Interventional ModelParallel Assignment
MaskingQuadruple
Primary PurposeTreatment
Official TitleA Randomized, Double-blind, Parallel-group, Placebo-controlled, Fixed-dose, Multicenter Study to Evaluate the Efficacy and Safety of SEP-363856 in Acutely Psychotic Subjects With Schizophrenia
Study Start DateOctober 13, 2019
Actual Primary Completion DateJune 13, 2023
Actual Study Completion DateJune 13, 2023

Groups and Cohorts

Group/CohortIntervention/Treatment
SEP-363856 75mg
SEP-363856 75mg dosed once daily
Drug: SEP-363856 75mg
SEP-363856 75mg tablet dosed once daily
SEP-363856 100mg
SEP-363856 100mg dosed once daily
Drug: SEP-363856 100mg
SEP-363856 100mg tablet dosed once daily
Placebo
Placebo dosed once daily
Drug: Placebo
Placebo tablet dosed once daily

Outcome Measures

Primary Outcome Measures
  1. Change From Baseline in PANSS Total Score at Week 6
    PANSS was an interview-based assessment comprised of 30 items and 3 subscales (Positive, Negative, General Psychopathology). The Positive subscale assessed hallucinations, delusions, and related symptoms; the Negative subscale assessed emotional withdrawal, lack of motivation, and similar symptoms; and the General Psychopathology subscale addressed other symptoms such as anxiety, somatic concern, and disorientation. An anchored Likert scale from 1 - 7, where values of 2 and above indicated the presence of progressively more severe symptoms, was used to score each item. Individual items were then summed to determine scores for the 3 subscales, as well as a total score. PANSS total score ranges from: 30-210, where a higher score indicates greater severity. A negative change from baseline indicates improvement.
Secondary Outcome Measures
  1. Change From Baseline in CGI-S Score at Week 6
    The CGI-S is a single-item clinician-rated assessment of the participant's current illness state on a 7-point scale (score range: 1-7), where a higher score is associated with greater illness severity. A negative change from baseline indicates improvement.

Eligibility Criteria

Ages Eligible for Study(Adult, Older Adult)
Sexes Eligible for StudyAll
Accepts Healthy VolunteersNo
Inclusion Criteria
1. Male or female participant between 18 to 65 years of age (inclusive) at the time of consent. 2. Participant must give written informed consent and privacy authorization prior to participation in the study. 3. Participant meets the Diagnostic and Statistical Manual of Mental Illnesses (DSM-5 )criteria for schizophrenia as established by clinical interview at screeing. 4. Participant must have a Clinical Global Impression - Severity (CGI-S) score ≥ 4. 5. Participant must have a Positive and Negative Syndrome Scale (PANSS) total score ≥ 80 and a PANSS item score ≥ 4 on 2 or more of the following PANSS items: delusions, conceptual disorganization, hallucinations, and unusual thought content. 6. Participant has an acute exacerbation of psychotic symptoms (persisting no longer than 2 months prior to providing informed consent). 7. Participant has marked deterioration of functioning in one or more areas. 8. Participant is, in the opinion of the Investigator, generally healthy based on screening medical history, physical examination (PE), neurological examination, vital signs, electrocardiogram (ECG) and clinical laboratory values.
Exclusion Criteria
1. Participant has a DSM-5 diagnosis or presence of symptoms consistent with a DSM-5 diagnosis other than schizophrenia. Exclusionary disorders include but are not limited to alcohol use disorder (within past 12 months), substance (other than nicotine or caffeine) use disorder within past 12 months, or lifetime history of significant substance abuse that, in the opinion of the Investigator or Sponsor, may have had a significant and potentially permanent impact on the brain or other body systems, major depressive disorder, bipolar I or II disorder, schizoaffective disorder, obsessive compulsive disorder, and posttraumatic stress disorder. Symptoms of mild to moderate mood dysphoria or anxiety are allowed so long as these symptoms are not the primary focus of treatment. 2. Participant is at significant risk of harming self, others, or objects based on Investigator's judgment. 3. Participant has any clinically significant unstable medical condition or any clinically significant chronic disease that in the opinion of the Investigator, would limit the participant's ability to complete and/or participate in the study 4. Female participant who is pregnant or lactating 5. Participant has any clinically significant abnormal laboratory value(s) at Screening as determined by investigator.

Contacts and Locations

Sponsors and CollaboratorsOtsuka Pharmaceutical Development & Commercialization, Inc.
Locations
Research Site | Rogers Arkansas, United States, 72758Research Site | Anaheim California, United States, 92805Research Site | Bellflower California, United States, 90706Research Site | Culver City California, United States, 90230Research Site | Long Beach California, United States, 90806Research Site | San Diego California, United States, 92102Research Site | Sherman Oaks California, United States, 91403Research Site | Hollywood Florida, United States, 33021Research Site | Miami Springs Florida, United States, 33166Research Site | Atlanta Georgia, United States, 30331Research Site | Decatur Georgia, United States, 30030Research Site | Chicago Illinois, United States, 60641Research Site | Lake Charles Louisiana, United States, 70629Research Site | Gaithersburg Maryland, United States, 20877Research Site | St Louis Missouri, United States, 63125Research Site | Marlton New Jersey, United States, 08053Research Site | New York New York, United States, 10032Research Site | Richardson Texas, United States, 75080Research Site | Burgas , Bulgaria, 8000Research Site | Kardzhali , Bulgaria, 6600Research Site | Novi Iskar , Bulgaria, 1282Research Site | Plovdiv , Bulgaria, 4000Research Site | Sofia , Bulgaria, 1202Research Site | Sofia , Bulgaria, 1431Research Site | Zagreb , Croatia, 10090Research Site | Daugavpils , Latvia, LV-5417Research Site | Riga , Latvia, LV-1005Research Site | Strenči , Latvia, LV-4730Research Site | Arkhangelsk , Russia, 163530Research Site | Engel's , Russia, 413124Research Site | Moscow , Russia, 117152Research Site | Moscow , Russia, 141371Research Site | Saint Petersburg , Russia, 188820Research Site | Saint Petersburg , Russia, 190005Research Site | Saint Petersburg , Russia, 192019Research Site | Saint Petersburg , Russia, 197341Research Site | Saratov , Russia, 410028Research Site | Saratov , Russia, 410060Research Site | Stavropol , Russia, 357034Research Site | Tomsk , Russia, 634014Research Site | Belgrade , Serbia, 11000Research Site | Kovin , Serbia, 26220Research Site | Kragujevac , Serbia, 34000Research Site | Niš , Serbia, 18000Research Site | Novi Kneževac , Serbia, 23330Research Site | Vršac , Serbia, 26300Research Site | Kharkiv , Ukraine, 61068Research Site | Kherson , Ukraine, 73488Research Site | Kyiv , Ukraine, 01030Research Site | Kyiv , Ukraine, 01133Research Site | Kyiv , Ukraine, 08631Research Site | Lviv , Ukraine, 79021Research Site | Vinnytsia , Ukraine, 21005
Study Documents (Full Text)
Documents provided by Otsuka Pharmaceutical Development & Commercialization, Inc.: Study Protocol  October 12, 2022Documents provided by Otsuka Pharmaceutical Development & Commercialization, Inc.: Statistical Analysis Plan  July 13, 2023