Trial Outcomes & Findings for A Clinical Study That Will Evaluate How Well SEP-363856 Works and How Safe it is in People With Schizophrenia That Switch to SEP-363856 From Their Current Antipsychotic Medication (NCT NCT05628103)
NCT ID: NCT05628103
Last Updated: 2025-11-12
Results Overview
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.
COMPLETED
PHASE3
101 participants
From the first dose of the study drug up to end of follow up (up to Week 9)
2025-11-12
Participant Flow
Participants took part in the study at 26 clinical sites in the United States (US) from 19 December 2022 to 01 April 2024.
A total of 243 participants were screened, of which 101 participants entered the study, and all 101 participants received at least one dose of SEP-363856 in the 8-week treatment period.
Participant milestones
| Measure |
SEP-363856
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.
|
|---|---|
|
Overall Study
STARTED
|
101
|
|
Overall Study
Safety Population
|
101
|
|
Overall Study
COMPLETED
|
83
|
|
Overall Study
NOT COMPLETED
|
18
|
Reasons for withdrawal
| Measure |
SEP-363856
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.
|
|---|---|
|
Overall Study
Adverse Event
|
7
|
|
Overall Study
Withdrawal by Subject
|
3
|
|
Overall Study
Lost to Follow-up
|
3
|
|
Overall Study
Lack of Efficacy
|
1
|
|
Overall Study
Non-Compliance With Study Drug
|
4
|
Baseline Characteristics
A Clinical Study That Will Evaluate How Well SEP-363856 Works and How Safe it is in People With Schizophrenia That Switch to SEP-363856 From Their Current Antipsychotic Medication
Baseline characteristics by cohort
| Measure |
SEP-363856
n=101 Participants
Participants received flexible doses of SEP-363856 50 to 100 mg/day, orally, 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.
|
|---|---|
|
Age, Continuous
|
48.1 years
STANDARD_DEVIATION 12.02 • n=10 Participants
|
|
Sex: Female, Male
Female
|
29 Participants
n=10 Participants
|
|
Sex: Female, Male
Male
|
72 Participants
n=10 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
18 Participants
n=10 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
83 Participants
n=10 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Asian
|
3 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Black or African American
|
64 Participants
n=10 Participants
|
|
Race (NIH/OMB)
White
|
32 Participants
n=10 Participants
|
|
Race (NIH/OMB)
More than one race
|
1 Participants
n=10 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=10 Participants
|
PRIMARY outcome
Timeframe: From the first dose of the study drug up to end of follow up (up to Week 9)Population: Safety population included all participants that were enrolled and received the study drug. Percentages are rounded off to the nearest decimal point.
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.
Outcome measures
| Measure |
SEP-363856
n=101 Participants
Participants received flexible doses of SEP-363856 50 to 100 mg/day, orally, 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.
|
|---|---|
|
Percentage of Participants Who Discontinued From the Study Due to Clinical Reasons
|
7.9 percentage of participants
Interval 2.7 to 13.2
|
SECONDARY outcome
Timeframe: From first dose of the study drug up to end of follow-up period (up to Week 9)Population: Safety population included all participants that were enrolled and received the study drug. Percentages are rounded off to the nearest decimal point.
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.
Outcome measures
| Measure |
SEP-363856
n=101 Participants
Participants received flexible doses of SEP-363856 50 to 100 mg/day, orally, 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.
|
|---|---|
|
Percentage of Participants Who Discontinued From the Study Due to Any Reason
|
17.8 percentage of participants
Interval 10.4 to 25.3
|
Adverse Events
SEP-363856
Serious adverse events
| Measure |
SEP-363856
n=101 participants at risk
Participants received flexible doses of SEP-363856 50 to 100 mg/day, orally, 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.
|
|---|---|
|
Psychiatric disorders
Schizophrenia
|
4.0%
4/101 • From first dose of study drug up to end of follow up period (up to Week 9)
Safety population included all participants that were enrolled and received the study drug.
|
Other adverse events
| Measure |
SEP-363856
n=101 participants at risk
Participants received flexible doses of SEP-363856 50 to 100 mg/day, orally, 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.
|
|---|---|
|
Gastrointestinal disorders
Dry mouth
|
3.0%
3/101 • From first dose of study drug up to end of follow up period (up to Week 9)
Safety population included all participants that were enrolled and received the study drug.
|
|
Gastrointestinal disorders
Nausea
|
3.0%
3/101 • From first dose of study drug up to end of follow up period (up to Week 9)
Safety population included all participants that were enrolled and received the study drug.
|
|
Nervous system disorders
Dizziness
|
5.0%
5/101 • From first dose of study drug up to end of follow up period (up to Week 9)
Safety population included all participants that were enrolled and received the study drug.
|
|
Psychiatric disorders
Insomnia
|
4.0%
4/101 • From first dose of study drug up to end of follow up period (up to Week 9)
Safety population included all participants that were enrolled and received the study drug.
|
Additional Information
Clinical Transparency
Otsuka Pharmaceutical Development & Commercialization, Inc.
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place