Pattern Separation, Brain Derived Neurotrophic Factors, and Mechanisms of Vortioxetine

The U.S. Food and Drug Administration approved vortioxetine to treat major depressive
disorder in 2013. Researchers believe vortioxetine may improve pattern separation and pattern
completion (i.e., a neurological function) in people with major depressive disorder; thus,
this research study aims to determine how vortioxetine increases a person's ability to think.
The current study is an open label trial, therefore, all participants will receive
vortioxetine. Furthermore, participants receive the vortioxetine at no cost. It will take
participants 6 weeks to complete this study. Participants are asked to come to the Mass
General Hospital campus for 1 screening visit which includes a full psychiatric evaluation,
and 5 additional study visits. During study visits, participants will meet with a clinician
and then complete computer based cognitive tests.

Inclusion Criteria:

1. Meets Diagnostic and Statistical Manual of Mental Disorders (Versions 4 and 5)
criteria for and Major Depressive Disorder.

2. Hamilton Depression Rating Scale-17 score greater than 18.

3. Men and women between ages >=18 and 65.

Exclusion Criteria:

1. Meets Diagnostic and Statistical Manual of Mental Disorders (versions 4 and 5)
criteria for schizophrenia, schizoaffective disorder, obsessive compulsive disorder.

2. Unable to follow instructions or otherwise unable to participate in the trial.

3. Pregnant women or women of child bearing potential who are not using a medically
accepted means of contraception (defined as oral contraceptive pill or implant,
condom, diaphragm, spermicide, intrauterine device, tubal ligation, partner with
vasectomy)

4. Patients who, in the investigator's judgment, pose a current, serious suicidal or
homicidal risk.

5. Serious or unstable medical illness including cardiovascular, hepatic, renal,
respiratory, endocrine, neurologic, or hematologic disease.

6. History of seizure disorder.

7. The following Diagnostic and Statistical Manual of Mental Disorders (Version 4)
diagnoses (any current or past history, except substance abuse disorders):

Organic mental disorders, schizoaffective disorder, delusional disorder, psychotic
disorders not elsewhere classified.

8. History of multiple adverse drug reactions or allergy to the study drugs.

9. Patients with mood congruent or mood incongruent psychotic features

10. Current use of other psychotropic drugs.

11. Clinical or laboratory evidence of hypothyroidism.

12. Patients who have failed to respond during the course of their current major
depressive episode to at least one adequate antidepressant trial, defined as six weeks
or more of treatment with citalopram 40 mg/day (or its antidepressant equivalent)

13. Patients who have had electroconvulsive therapy within the 6 months preceding
baseline.

14. Concomitant use of serotonergic agents

15. Meets Diagnostic and Statistical Manual of Mental Disorders (versions 4 and 5)
criteria for bipolar disorder