Add-On Study of MSI-195 (S-Adenosyl-L-Methionine, SAMe) for Patients With Major Depressive Disorder (MDD)

A Double-Blind, Placebo-Controlled, Randomized Add-On Study of MSI-195 (Methylation Sciences Inc. S-Adenosyl-L-Methionine, SAMe) For Patients With Major Depressive Disorder(MDD) Who Have Had An Inadequate Response to Current Antidepressant Therapy

The purpose of this study is to determine the efficacy and safety of 800 mg MSI-195 in reducing symptoms of depression in Major Depressive Disorder (MDD)patients with inadequate response to current antidepressant therapy.

Inclusion Criteria:

• Meets the Diagnostic and Statistical Manual of Mental Disorder, 4th Edition, Text Revision (DSM-IV-TR) criteria for Major Depressive Disorder (MDD)
• A total score of 16 or higher on the Hamilton Rating Scale for Depression- 17 item version (HAM-D17) at the Screening and Baseline Visits, with a score of ≥2 on mood item 1.
• Have experienced 1-4 prior Major Depressive Episodes. Patients with more than 5 lifetime episodes (including current episode) will require discussion with the medical monitor prior to inclusion.
• Failed 1-3 treatment regimens in the current depressive episode
• Received an adequate dose and duration of Antidepressant Therapy (ADT) (on ADT for at least 6 weeks with a stable dose for at least 3 weeks)

Exclusion Criteria:

• Failed 4 or more adequate treatment regimens in current episode of depression
• patient may have a significant risk for suicidal behavior during the course of their participation in the study
• Intolerance to SAMe; Prior use of MSI-195
• History of any of the following psychiatric disorders: eating disorder within 6 months; obsessive compulsive disorder, psychotic disorder, bipolar disorder, mental retardation, dementia or other forms of cognitive impairment at any time or alcohol or substance abuse
• >3X upper limit of normal (ULN) Alkaline Phosphatase, aspartate aminotransferase (AST), alanine aminotransferase (ALT); >1.5X ULN total bilirubin
• Pregnant or lactating women
• Any history of seizures, excluding febrile seizures
• Known positivity for human immunodeficiency virus