Near-infrared Transcranial Laser Therapy in Subjects With Major Depressive Disorder: A Study of Dosing With Laser

Inclusion Criteria:

1. Subjects age at screening will be between 18 and 75 years old (inclusive).
2. Diagnosis of major depressive disorder (Mini International Neuropsychiatric Interview,MINI)
3. QIDS-CR≥12 at screening
4. CGI-S ≥4 or higher, i.e., "moderately depressed"
5. Women of child-bearing potential must use a double-barrier method for birth control (e.g. condoms plus spermicide) if sexually active.
6. Subject Informed Consent obtained in writing in compliance with local regulationsprior to enrollment into this study.
7. The subject is willing to participate in this study for at least 12 weeks.
8. Subjects will need to be on stable dose(s) of antidepressants (if taking any) for atleast six weeks prior to enrollment.

Exclusion Criteria:

1. Decrease in Symptoms of Depression Questionnaire (SDQ) self-report from screening tobaseline >=30%, calculated as [(SDQ screening-88) - (SDQ initial-88) / (SDQscreening-88)] >=30/100. A score of 88 is "normal" in SDQ.
2. The subject is pregnant or lactating.
3. The subject failed more than 2 adequate treatments with FDA approved antidepressantsduring current episode per Antidepressant Treatment Response Questionnaire (ATRQ)criteria (less than 50% decrease in depressive symptomatology).
4. Structured psychotherapy focused on treating the subject's depression is permitted ifstarted at least 8 weeks prior to the screening visit.
5. Substance dependence or abuse in the past 3 months.
6. History of a psychotic disorder or psychotic episode (current psychotic episode perMINI assessment).
7. Bipolar affective disorder (per MINI assessment).
8. Unstable medical illness, defined as any medical illness which is not well-controlledwith standard-of-care medications (e.g., insulin for diabetes mellitus).
9. Active suicidal or homicidal ideation (both intention and plan are present), asdetermined by Columbia-Suicide Severity Rating Scale (C-SSRS) screening.
10. The subject has a significant skin condition (i.e., hemangioma, scleroderma,psoriasis, rash, open wound or tattoo) on the subject's scalp that is found to be inproximity to any of the procedure sites.
11. The subject has an implant of any kind in the head (e.g. stent, clipped aneurysm,implantable shunt - Hakim valve).
12. Any use of light-activated drugs (photodynamic therapy) within 14 days prior to studyenrollment (in US: Visudine (verteporfin) for age related macular degeneration;Aminolevulinic Acid- for actinic keratoses; Photofrin (porfimer sodium) - foresophageal cancer, non-small cell lung cancer; Levulan Kerastick (aminolevulinic acidHCl) - for actinic keratosis; 5-aminolevulinic acid (ALA)- for non-melanoma skincancer)
13. Recent history of stroke (90 days).
14. The subject failed a device-based intervention FDA-approved for the treatment ofdepression, during the current episode (e.g. less than 50% decrease in depressivesymptomatology with Transcranial Magnetic Stimulation).
15. History of dementia, traumatic brain injury (TBI) or any other organic neurologicaldisorder.