Phase 2, Double-Blind, Placebo-Controlled, Randomized Withdrawal, Parallel Efficacy and Safety Study of GLYX- 13 in Subjects with Inadequate/Partial Response to Antidepressants during the Current Episode of Major Depressive Disorder

Summary

Phase 2, double-blind, placebo-controlled, parallel, 6-week randomized withdrawal study following a 6-
week partial double blind stabilization period with adaptive dosing interval-finding.


On Week 1 Day 1, Each subject[Right Quote]s eligibility will be confirmed;Each subject will then
receive an IV dose of GLYX-13 (5 mg/kg or 10 mg/kg) by infusion over approximately 1 to 3.5 minutes
depending upon mass, under partial double blind conditions.

During the 6-week stabilization phase, If HDRS-17 score is reduced
and amp;gt;50% from predose (baseline) score, then the subject will receive an IV injection of placebo. If score is
reduced and amp;lt;50% from predose baseline, subject will receive an IV dose of GLYX-13.

At the Week 7 visit, One-third of subjects from each dose group will be randomized to receive IV injections of placebo. The other two-thirds of subjects from each dose group will be randomized to continue
to receive IV injections of GLYX-13

Subjects who do not achieve and amp;gt;50% reduction in HDRS-17 score from predose baseline at least twice
during the stabilization phase will be terminated from the study after HDRS-17 assessment at the Week 7
visit.
At the end of the 6-week randomized withdrawal period (Week 13 visit) all subjects who have an HDRS-
17 score reduced and amp;lt;50% from predose baseline will be terminated from the study. All subjects who have
HDRS-17 scores reduced and amp;gt;50% from predose baseline will continue to return weekly up to 4 weeks (Washout Phase) to receive single blind injections of placebo. If at any visit, HDRS- 17 score has increased such that HDRS-17 score is within 20% of predose baseline, the subject will be terminated from the study

Participant Eligibility

1. Male and female subjects
2. Aged 18 to 65 years
3. Meets Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR)
criteria for major depressive disorder (MDD)
4. Current episode has lasted >= 8 weeks before Screening with an inadequate response
(<50% reduction in the Antidepressant Treatment Response Questionnaire [ATRQ]) to all
approved antidepressant agent(s) administered at an adequate dose and duration for the
current episode
5. Taking no antidepressant agent currently or taking an SSRI or SNRI from among the
following: SSRI: SSRIs: citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine,
paroxetine CR, sertraline; SNRIs: desvenlafaxine, duloxetine, venlafaxine, venlafaxine
XR, to treat their depression. any adjunctive agent to treat depression must have been stopped at least 14 days prior to dosing study drug.
6. HDRS-17 score >= 18 at screening.
7. HDRS-17 score >= 18 at predose baseline.
8. Female subjects of childbearing potential with a negative pregnancy test prior to
entry into the study and who are practicing an adequate method of birth control (eg oral
or parenteral contraceptives, intrauterine device, barrier, abstinence) and who do not plan
to become pregnant during the course of the study. Female subjects may be included
without a negative pregnancy test if they are surgically sterile or at least 2 years
post-menopausal.
9. Clinical laboratory values < 2 times the upper limit of normal (ULN) or deemed not
clinically significant per the investigator and Naurex medical monitor
10. Ability to understand the requirements of the study, provide written informed consent,
abide by the study restrictions, and agree to return for the required assessments
11. Based on the investigator and Naurex medical monitor[Single Quote]s clinical judgment, subjects with
eating disorders, obsessive compulsive disorder (OCD), panic disorder, post-traumatic
stress disorder (PTSD), and generalized anxiety disorders secondary to major depressive
episodes (MDEs) are permitted.