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

Study purpose: To assess and compare the effect(s) of each of the four doses of NIR-TLT on symptomatology of depression: antidepressant effect, in subjects with major depressive disorder (MDD). To assess the safety and tolerability of each dose of NIR-TLT. Compare the effect(s) of each of the four doses of NIR-TLT in brain electrophysiology. To describe the findings visualized in PET, related to the cerebral metabolism of the participants, before and after receiving the intervention under study. Study design: This protocol is a multicentered, randomized, simulated, and double-blind clinical study. This work will randomize 112 subjects into 4 equal groups: bilateral continuous wave (BCW), bilateral pulsed wave (BPW 1-2) y SHAM. All subjects, investigators (except the study statistician), and outcomes assessors will be blind to group assignment. The device operator will be aware of group assignments. All subjects will receive 3 NIR-TLT treatments per week for 6 weeks. A follow-up evaluation will be performed 2 weeks after the end of the study. The treatment will follow these specifications: wavelength 830 nm; average irradiance 54,8 mW / cm2; average fluence of 65,8 J / cm2 (consistently with parameters used in the ELATED-2 study at MGH with the device Omnilux New U), being the total Fluency delivered: 3.6 kJ (bilateral) o 1.8 kJ (unilateral), either on the subject's forehead, at or near electroencephalography sites (EEG) F3 and F4. All NIR-TLT sessions will last 20 minutes, regardless of group assignment. Study population: Patients eligible for study participation will be diagnosed with major depressive disorder (MDD) by DSM criteria. Subjects will be between 18-75 years of age (have not had 76st birthday) on the date of screening. Duration of participation: Subjects will be followed in the study for 8 weeks (a 6-week treatment period, plus 2 weeks of follow-up). The total duration of the study will be 24 months. Assessment criteria: The primary efficacy criteria is the improvement in depressive symptoms from each of the four doses of NIR-TLT. Assessed using HAMD-17, at 3 time points (visit 1, visit 9 and visit 18).