A Study of Rapastinel as Adjunctive Therapy in the Prevention of Relapse in Patients With Major Depressive Disorder

Study Overview
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Brief Summary
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This study will evaluate the efficacy, safety and tolerability of rapastinel 450 milligrams (mg) intravenous (IV) once weekly or once every 2 weeks versus placebo as an adjunctive treatment to ongoing anti-depressive therapy (ADT) in the prevention of relapse in participants with Major Depressive Disorder (MDD).

Official Title
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A Randomized, Double-blind, Placebo-controlled, Multicenter Study of Rapastinel as Adjunctive Therapy in the Prevention of Relapse in Patients With Major Depressive Disorder

Conditions
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Depressive Disorder, Major

Intervention / Treatment
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* Drug: Rapastinel
* Drug: Placebo-matching Rapastinel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Meet Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for MDD Current major depressive episode of at least 8 weeks and not exceeding 18 months in duration at Screening Have no more than partial response (< 50% improvement) to ongoing treatment with a protocol-allowed antidepressant If female of childbearing potential, have a negative serum β-human chorionic gonadotropin (β-hCG) pregnancy test. Exclusion Criteria: DSM-5-based diagnosis of any disorder other than MDD that was the primary focus of treatment within 6 months before Screening Lifetime history of meeting DSM-5 criteria for: Schizophrenia spectrum or other psychotic disorder Bipolar or related disorder Major 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 Dissociative disorder Posttraumatic stress disorder MDD with psychotic features Significant suicide risk, as judged by the Investigator.

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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Rapastinel 450 mg Weekly<br>Rapastinel 450 milligrams (mg) intravenous (IV) once a week during OLTP followed by rapastinel 450 mg IV once a week during DBTP. | Drug: Rapastinel<br>* Rapastinel pre-filled syringes for IV injections.<br>|
| Experimental: Rapastinel 450 mg Every 2 Weeks<br>Rapastinel 450 mg IV once a week during OLTP followed by rapastinel 450 mg IV once every 2 weeks during DBTP. | Drug: Rapastinel<br>* Rapastinel pre-filled syringes for IV injections.<br>|
| Placebo Comparator: Placebo<br>Rapastinel 450 mg IV once a week during OLTP followed by placebo-matching rapastinel 450 mg IV once a week during DBTP. | Drug: Placebo-matching Rapastinel<br>* Placebo-matching rapastinel pre-filled syringes for weekly IV injections.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to First Relapse During the First 52 Weeks of the Double-Blind Treatment Period | The time in days to first relapse is defined as the number of days from the date of randomization to the first relapse. | 52 Weeks | 
| Number of Participants Experiencing Suicidal Ideation or Suicidal Behavior Based on Columbia-Suicide Severity Rating Scale (C-SSRS) Using 5-Point Scales | On the C-SSRS, the 5 types of suicidal ideation are: Type 1: Wish to be dead Type 2: Non-specific active suicidal thoughts Type 3: Active suicidal ideation with any methods (not plan) without intent to act Type 4: Active suicidal ideation with some intent to act, without specific plan Type 5: Active suicidal ideation with specific plan and intent | 104 Weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to First Relapse During the Entire Double-Blind Treatment Period | The time in days to first relapse is defined as the number of days from the date of randomization to the first relapse. | 104 Weeks |