SchizophreniaPhase 3NCT04115319
A Study of the Long-term Safety and Tolerability of an Investigational Drug in People With Schizophrenia.
A Phase 3 study testing SEP363856 and quetiapine XR in people with Schizophrenia, run by Otsuka Pharmaceutical Development & Commercialization, Inc. at 42 sites in 4 countries.
Trial summary
A clinical study to evaluate the long-term safety and tolerability of an investigational drug in people with schizophrenia. This study is accepting male and female participants between 18 years old -65 years old who have been diagnosed with schizophrenia. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Schizophrenia
- What is being tested?
- SEP363856 and quetiapine XR
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 305 participants
- Where
- 42 sitesin 4 countries
- Study dates
- 21 Nov 2019to 30 Dec 2022
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- The main inclusion criteria include, but are not limited to the following:
- Male or female participant between 18 to 65 years of age (inclusive) at the time of consent.
- Participant meets DSM-5 criteria for a diagnosis of schizophrenia as established by clinical interview at screening (using the DSM-5 as a reference and confirmed using the SCID-CT). The time since the participant's diagnosis must be ≥ 1 year prior to Screening.
- Participant must have a CGI-S score ≤ 4 at Screening and Baseline.
- Participant must have a PANSS total score ≤ 80 at Screening and Baseline.
- Participant is judged to be clinically stable (i.e., no evidence of an acute exacerbation) by the Investigator for at least 8 weeks prior to Screening.
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- Participant has had no change in antipsychotic medication(s) (minor dose adjustments for tolerability purposes are permitted) for at least 6 weeks prior to Screening.
- Participants taking an antipsychotic agent at Screening may participate in this study only if there are signs of intolerability or lack of efficacy of the current antipsychotic (as determined by the Investigator).
- Participant is, in the opinion of the Investigator, generally healthy based on Screening medical history, PE, neurological examination, vital signs, electrocardiogram (ECG) and clinical laboratory values (hematology, chemistry and urinalysis).
Who cannot join
- Main exclusion criteria include, but are not limited to:
- Participant was hospitalized for a psychiatric illness within the 8 weeks prior to Screening.
- Participant has a current 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, schizoaffective disorder, ,bipolar I or II disorder, obsessive compulsive disorder, and posttraumatic stress disorder, symptoms of mild to moderate mood dysphoria or anxiety are allowed so long as theses symptoms are not the primary focus of treatment.
- Participant is judged to be resistant to antipsychotic treatment by the Investigator, based on failure to respond to 2 or more marketed antipsychotic agents within a 1-year period prior to Screening, given at adequate dose as per labeling, for at least 4 weeks.
- Participant answers "yes" to "Suicidal Ideation" Item 4 (active suicidal ideation with some intent to act, without specific plan) or Item 5 (active suicidal ideation with specific plan and intent) on the C-SSRS assessment at Screening (i.e., in the past one month) or at Baseline (i.e., since last visit).
- Participant is at significant risk of harming self or others based on Investigator's judgment.
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- Participant has attempted suicide within 6 months prior to Screening.
- Participant has received treatment with a psychotropic medication or herbal supplement within 3 days or 5 half-lives (whichever is longer)
- Participant has been treated with quetiapine or quetiapine XR within the 6 weeks prior to Screening or has a history of inadequate response or intolerability to quetiapine or quetiapine XR.
- 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.
- Participant has any clinically significant abnormal laboratory value(s) at Screening as determined by investigator.
Trial locations and contacts
42 sites in 4 countries.
42 sites in 4 countries
United States18 sites
Research Site
Atlanta, Georgia, 30328
Research Site
Cedarhurst, New York, 11516
Research Site
Cerritos, California, 90703
Research Site
Charlotte, North Carolina, 28211
Research Site
Hoffman Estates, Illinois, 60169
Research Site
Jamaica, New York, 11432
Research Site
Las Vegas, Nevada, 89102
Research Site
Lincolnwood, Illinois, 60712
Research Site
Miami, Florida, 33122
Research Site
Miami Lakes, Florida, 33016
Research Site
North Canton, Ohio, 44720
Research Site
Oakland, California, 94607
Research Site
Oceanside, California, 92056
Research Site
Rochester, New York, 14618
Research Site
San Diego, California, 92103
Research Site
Shreveport, Louisiana, 71101
Research Site
St Louis, Missouri, 63128
Research Site
Torrance, California, 90502
Russia13 sites
Research Site
Arkhangelsk, 163530
Research Site
Moscow, 127083
Research Site
Omsk, 644070
Research Site
Saint Petersburg, 188357
Research Site
Saint Petersburg, 190121
Research Site
Saint Petersburg, 192019
Research Site
Saint Petersburg, 195176
Research Site
Saint Petersburg, 199106
Research Site
Smolensk, 214031
Research Site
Stavropol, 357034
Research Site
Tomsk, 634014
Research Site
Yaroslavl, 150003
Research Site
Yekaterinburg, 620030
Ukraine6 sites
Research Site
Ivano-Frankivsk, 76011
Research Site
Kharkiv, 61068
Research Site
Kyiv, 03049
Research Site
Smila, 20708
Research Site
Ternopil, 46027
Research Site
Uzhhorod, 88000
Romania5 sites
Research Site
Brasov, 500079
Research Site
Bucharest, 041914
Research Site
Bucharest, 060222
Research Site
Bucharest, 41914,
Research Site
Iași, 700282
About this study
Official title: A Randomized, Double-blind, Active Comparator-Controlled Study to Evaluate the Long-term Safety and Tolerability of SEP-363856 in Subjects With Schizophrenia
A clinical study to evaluate the long-term safety and tolerability of an investigational drug in people with schizophrenia.
This study is accepting male and female participants between 18 years old -65 years old who have been diagnosed with schizophrenia. This study will be conducted in approximately 50 study centers worldwide. The study will last approximately 57 weeks.
Read the detailed description
This is a 52-week, multicenter, randomized, double-blind, parallel-group, flexible-dose study designed to evaluate the long-term safety and tolerability of SEP-363856 (50 to 100 mg/day) compared with quetiapine XR (400 to 800 mg/day) in clinically stable adult participants with schizophrenia. This study is projected to randomize a least 300 participants to two treatment groups (SEP-363856 50 to 100 mg/day or quetiapine XR 400 to 800 mg/day) in a 2:1 ratio. Study drug will be taken once a day and may be taken without food or with a light meal.
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.
- Conditions
- Schizophrenia
- Being tested
- SEP363856, quetiapine XR
- Keywords
- schizophrenia
- Medical subject headings
- Schizophrenia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SEP363856Drug
SEP-363856, 50mg, 75mg, 100mg, flexibly dosed once daily capsule
quetiapine XRDrug
Also called Seroquel XR
quetiapine XR, 400, 600, 800 mg, flexibly dosed once daily capsule
| Study group | Role | What they receive |
|---|---|---|
| SEP363856 | Experimental | SEP363856 50mg, 75mg, 100mg, flexibly dosed once daily capsule Receives: Drug: SEP363856 |
| quetiapine XR | Active comparator | quetiapine XR, 400, 600, 800 mg, flexibly dosed once daily capsule Receives: Drug: quetiapine XR |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), and Adverse Events (AEs) Leading to Study Discontinuation
An AE was any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug related. Untoward medical occurrences that occured after first administration of study drug were considered AEs. A SAE is an AE that meets one or more criteria: results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in persistent or significant disability or incapacity, or is a congenital anomaly or birth defect.
Measured: From first dose of the study drug up to 7 days after last dose of study drug (Up to 53 weeks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Oct 2019
- Study start21 Nov 2019
- Primary completion30 Dec 2022
- Study completion30 Dec 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for SchizophreniaStudies of the same condition, open and under way.
- More trials run by Otsuka Pharmaceutical Development & Commercialization, Inc.The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- A Randomized, Double-blind, Active Comparator-Controlled Study
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 305 participants (actual)
Sponsor and investigators
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04115319
- Sponsor's protocol ID
- SEP361-304
- Other IDs
- 2019-002259-40, 2019
- Status last verified
- Sep 2024
- First submitted
- 2 Oct 2019
- Last updated
- 31 Dec 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Anonymized Individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.
Study at a glance
From the registry record, last updated by the sponsor on 31 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomized, Double-blind, Active Comparator-Controlled Study to Evaluate the Long-term Safety and Tolerability of SEP-363856 in Subjects With Schizophrenia
- ClinicalTrials.gov ID
- NCT04115319
- Acronym / sponsor ID
- SEP361-304
- Conditions
- Schizophrenia
- Keywords
- schizophrenia
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 305 participants (actual)
- Lead sponsor
- Otsuka Pharmaceutical Development & Commercialization, Inc.Industry (pharma, biotech, devices)
- Study start
- 21 Nov 2019 (actual)
- Primary completion
- 30 Dec 2022 (actual)
- Study completion
- 30 Dec 2022 (actual)
- First posted
- 4 Oct 2019 (actual)
- Results
- Posted 31 Dec 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A clinical study to evaluate the long-term safety and tolerability of an investigational drug in people with schizophrenia.
This study is accepting male and female participants between 18 years old -65 years old who have been diagnosed with schizophrenia. This study will be conducted in approximately 50 study centers worldwide. The study will last approximately 57 weeks.
Detailed description
This is a 52-week, multicenter, randomized, double-blind, parallel-group, flexible-dose study designed to evaluate the long-term safety and tolerability of SEP-363856 (50 to 100 mg/day) compared with quetiapine XR (400 to 800 mg/day) in clinically stable adult participants with schizophrenia. This study is projected to randomize a least 300 participants to two treatment groups (SEP-363856 50 to 100 mg/day or quetiapine XR 400 to 800 mg/day) in a 2:1 ratio. Study drug will be taken once a day and may be taken without food or with a light meal.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- A Randomized, Double-blind, Active Comparator-Controlled Study
| Arm | Type | Receives |
|---|---|---|
| SEP363856 | Experimental | Drug: SEP363856SEP363856 50mg, 75mg, 100mg, flexibly dosed once daily capsule |
| quetiapine XR | Active comparator | Drug: quetiapine XRquetiapine XR, 400, 600, 800 mg, flexibly dosed once daily capsule |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Male or female participant between 18 to 65 years of age (inclusive) at the time of consent.
- Participant meets DSM-5 criteria for a diagnosis of schizophrenia as established by clinical interview at screening (using the DSM-5 as a reference and confirmed using the SCID-CT). The time since the participant's diagnosis must be ≥ 1 year prior to Screening.
- Participant must have a CGI-S score ≤ 4 at Screening and Baseline.
- Participant must have a PANSS total score ≤ 80 at Screening and Baseline.
- Participant is judged to be clinically stable (i.e., no evidence of an acute exacerbation) by the Investigator for at least 8 weeks prior to Screening.
Key exclusion criteria (11 listed)
- Participant was hospitalized for a psychiatric illness within the 8 weeks prior to Screening.
- Participant has a current 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, schizoaffective disorder, ,bipolar I or II disorder, obsessive compulsive disorder, and posttraumatic stress disorder, symptoms of mild to moderate mood dysphoria or anxiety are allowed so long as theses symptoms are not the primary focus of treatment.
- Participant is judged to be resistant to antipsychotic treatment by the Investigator, based on failure to respond to 2 or more marketed antipsychotic agents within a 1-year period prior to Screening, given at adequate dose as per labeling, for at least 4 weeks.
- Participant answers "yes" to "Suicidal Ideation" Item 4 (active suicidal ideation with some intent to act, without specific plan) or Item 5 (active suicidal ideation with specific plan and intent) on the C-SSRS assessment at Screening (i.e., in the past one month) or at Baseline (i.e., since last visit).
- Participant is at significant risk of harming self or others based on Investigator's judgment.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| SEP363856SEP-363856, 50mg, 75mg, 100mg, flexibly dosed once daily capsule | Drug | SEP363856 |
| quetiapine XRAlso: Seroquel XRquetiapine XR, 400, 600, 800 mg, flexibly dosed once daily capsule | Drug | quetiapine XR |
Primary outcome
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), and Adverse Events (AEs) Leading to Study Discontinuation
Time frame: From first dose of the study drug up to 7 days after last dose of study drug (Up to 53 weeks)
An AE was any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug related. Untoward medical occurrences that occured after first administration of study drug were considered AEs. A SAE is an AE that meets one or more criteria: results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in persistent or significant disability or incapacity, or is a congenital anomaly or birth defect.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 31 Dec 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. Anonymized Individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
42 sites in 4 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing SEP363856 and quetiapine XR in people with Schizophrenia, run by Otsuka Pharmaceutical Development & Commercialization, Inc. at 42 sites in 4 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 31 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 42 sites in United States, Russia, Ukraine, Romania. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 31 Dec 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), and Adverse Events (AEs) Leading to Study Discontinuation (time frame: From first dose of the study drug up to 7 days after last dose of study drug (Up to 53 weeks)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 31 Dec 2025.