A Trial of the Safety and Efficacy of SEP-363856 in the Treatment of Adults With Major Depressive Disorder

Study Overview
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Brief Summary
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This is a Phase 2/3, Multicenter, Randomized, Double-blind, Placebo-controlled Trial of the Safety and Efficacy of Flexible Doses of SEP-363856 as Adjunctive Therapy in the Treatment of Adults with Major Depressive Disorder (MDD)

Official Title
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A Phase 2/3, Multicenter, Randomized, Double-blind, Placebo-controlled Trial of the Safety and Efficacy of Flexible Doses of SEP-363856 as Adjunctive Therapy in the Treatment of Adults With Major Depressive Disorder

Conditions
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Major Depressive Disorder

Intervention / Treatment
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* Drug: SEP-363856
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and Female subjects between 18-65 years of age, with a primary diagnosis of major depressive disorder and in a current major depressive episode Current major depressive episode must be at least 8 weeks and no longer than 2 years in duration History of an inadequate response to at least 1 and no more than 3 antidepressant treatments in the current major depressive episode Exclusion Criteria: Subjects who report an inadequate response to more than 3 antidepressant treatments in the current episode Subjects with a lifetime history of schizophrenia spectrum or other psychotic disorder, bipolar or related disorder, major or mild neurocognitive disorder, neurodevelopmental disorder of greater than mild severity or of a severity that impacts the participant's ability to consent/ follow study directions/ or otherwise safely participate in the study, borderline or antisocial personality disorder. Subjects with a current diagnosis of post-traumatic stress disorder, obsessive compulsive disorder, panic disorder, or eating disorder (including anorexia nervosa or bulimia). Sexually active subjects, who could become pregnant, not agreeing to practice 2 sponsor approved methods of birth control or remain abstinent during the trial and for 30 days (females) or 90 days (males) after last dose of study drug.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SEP-363856 & ADT (Antidepressant Therapy)<br> | Drug: SEP-363856<br>* Tablet<br>|
| Placebo Comparator: Placebo & ADT (Antidepressant Therapy)<br> | Other: Placebo<br>* Placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Montgomery Åsberg Depression Rating Scale (MADRS) | Change from the baseline to the Montgomery Åsberg Depression Rating Scale (MADRS) total score. The Montgomery Åsberg Depression Rating Scale consists of 10 items, each rated from 0 to 6 (for a total score of 0 to 60). A higher score represents a higher severity of the level of depression. | From baseline to week 14 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical Global Impression - Severity of Illness (CGI-S) | Change from baseline in the Clinical Global Impression - Severity of Illness (CGI-S). Clinical Global Impression - Severity of Illness will be measured on a scale from 1-7 where a higher score represents a higher severity of disease. | From baseline to week 14 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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MDD, SEP-363856, Antidepressant Therapy, ADT, Depression, Depressive Disorder, Major Mood Disorders, Mental Disorders