A Phase 3 interventional study of SEP-363856 in Schizophrenia, sponsored by Otsuka Pharmaceutical Development & Commercialization, Inc.. Completed at 25 sites in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-12-11.
Sponsored by Otsuka Pharmaceutical Development & Commercialization, Inc. · Phase 3, Interventional, and Treatment
This study evaluated how well SEP-363856 works and how safe it is in people with schizophrenia that switch to SEP-363856 from their current antipsychotic medication.
This was an 8-week, outpatient, multicenter, open-label, single-group, flexible-dose study.
Following a screening period of up to 21 days, eligible participants took part in the study. In the 8-week treatment period, participants were treated with SEP-363856 while continuing to take the full dose of their pre-switch antipsychotic. After the end of the treatment period, participants were required to complete the follow-up visit, 7 days after the last dose of SEP-363856.
3,471 studies on the registry are indexed under Schizophrenia; 472 are open to participants now.
This study's enrollment of 101 is above the median of 70 across 2,872 interventional studies indexed under Schizophrenia.
Browse Schizophrenia studies →Otsuka Pharmaceutical Development & Commercialization, Inc. is the lead sponsor of 289 studies on the registry; 18 are open to participants now.
Of its 104 completed or terminated interventional studies of FDA-regulated products, 69 (66%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria: This list is not all inclusive
Exclusion Criteria:This list is not all inclusive
Participants received flexible doses of SEP-363856 50 to 100 milligrams per day (mg/day), orally, once daily (QD) up to Week 8. The dose was titrated up from 50 mg/day on Days 1 to 3, to 75 mg/day on Days 4 to 7. Beginning Day 8, the dose was adjusted within the range of 50 mg/day to 100 mg/day in 25 mg increments (i.e. 50, 75, or 100 mg/day) up to Week 8.
Drug: SEP-363856
SEP-363856 flexibly dosed for 8 weeks.
Percentage of Participants Who Discontinued From the Study Due to Clinical Reasons
Discontinuation for clinical reasons was defined as reasons due to adverse event (AE) or lack of efficacy. AEs are defined as untoward medical occurrences that started at the same time of or after the first dose of study drug. The percentage of participants who discontinued for clinical reasons was calculated by a proportion consisting of the number of participants who experience a discontinuation event due to clinical reasons as the numerator divided by the number of participants in the safety population as the denominator multiplied by 100 along with a corresponding 95% confidence interval (CI). 95% CI was calculated using the normal approximation method.
Time frame: From the first dose of the study drug up to end of follow up (up to Week 9)
Percentage of Participants Who Discontinued From the Study Due to Any Reason
The percentage of participants who discontinued from the study due to any reason was calculated by a proportion consisting of the number of participants who experience a discontinuation event due to any reason as the numerator divided by the number of participants in the safety population as the denominator multiplied by 100 along with a corresponding 95% CI. 95% CI was calculated using the normal approximation method.
Time frame: From first dose of the study drug up to end of follow-up period (up to Week 9)
Participants took part in the study at 26 clinical sites in the United States (US) from 19 December 2022 to 01 April 2024.
| Milestone | SEP-363856 |
|---|---|
| Started | 101 |
| Safety population | 101 |
| Completed | 83 |
| Not completed | 18 |
| Withdrew: Adverse event | 7 |
| Withdrew: Withdrawal by subject | 3 |
| Withdrew: Lost to follow-up | 3 |
| Withdrew: Lack of efficacy | 1 |
| Withdrew: Non-compliance with study drug | 4 |
Discontinuation for clinical reasons was defined as reasons due to adverse event (AE) or lack of efficacy. AEs are defined as untoward medical occurrences that started at the same time of or after the first dose of study drug. The percentage of participants who discontinued for clinical reasons was calculated by a proportion consisting of the number of participants who experience a discontinuation event due to clinical reasons as the numerator divided by the number of participants in the safety population as the denominator multiplied by 100 along with a corresponding 95% confidence interval (CI). 95% CI was calculated using the normal approximation method.
| percentage of participants | SEP-363856 |
|---|---|
| Percentage of Participants Who Discontinued From the Study Due to Clinical Reasons | 7.9 (2.7 to 13.2) |
The percentage of participants who discontinued from the study due to any reason was calculated by a proportion consisting of the number of participants who experience a discontinuation event due to any reason as the numerator divided by the number of participants in the safety population as the denominator multiplied by 100 along with a corresponding 95% CI. 95% CI was calculated using the normal approximation method.
| percentage of participants | SEP-363856 |
|---|---|
| Percentage of Participants Who Discontinued From the Study Due to Any Reason | 17.8 (10.4 to 25.3) |
Collected over From first dose of study drug up to end of follow up period (up to Week 9). Non-serious events are listed at a 2% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| SEP-363856 | 0/101 (0%) | 4/101 (4%) | 13/101 (12.9%) |
| Event | SEP-363856 |
|---|---|
| SchizophreniaPsychiatric disorders | 4/101 |
| Event | SEP-363856 |
|---|---|
| DizzinessNervous system disorders | 5/101 |
| InsomniaPsychiatric disorders | 4/101 |
| Dry mouthGastrointestinal disorders | 3/101 |
| NauseaGastrointestinal disorders | 3/101 |
Safety population included all participants that were enrolled and received the study drug.
| Age, Continuous(years) | SEP-363856 |
|---|---|
| Mean | 48.1 ± 12.02 |
| Sex: Female, Male(Participants) | SEP-363856 |
|---|---|
| Female | 29 |
| Male | 72 |
| Ethnicity (NIH/OMB)(Participants) | SEP-363856 |
|---|---|
| Hispanic or Latino | 18 |
| Not Hispanic or Latino | 83 |
| Unknown or Not Reported | 0 |
| Race (NIH/OMB)(Participants) | SEP-363856 |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 3 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 64 |
| White | 32 |
| More than one race | 1 |
| Unknown or Not Reported | 1 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: 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.
Supporting information: Study protocol, Sap, Icf
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Otsuka Pharmaceutical Development & Commercialization, Inc.