This pilot study aims at exploring the efficacy of iTBS compared to 10Hz protocol and explore potential biomarkers of treatment response

Inclusion Criteria:

• outpatients
• voluntary and competent to consent
• Mini-International Neuropsychiatric Interview (MINI) confirmed diagnosis of Major Depressive Disorder (MDD), single, recurrent between ages 18-65
• failed to achieve a clinical response to an adequate dose of an antidepressant based on an Antidepressant Treatment History Form (ATHF) score of ≥ 3 in the current episode or have been unable to tolerate at least 2 separate trials of antidepressants of inadequate dose and duration (ATHF 1 or 2)
• have a score of ≥ 18 on the Hamilton Depression Rating Score 17-item (HDRS-17)
• have had no increase or initiation of any psychotropic medication in the 4 weeks prior to screening able to adhere to the treatment schedule
• Pass the TMS adult safety screening (TASS) questionnaire
• have normal thyroid functioning based on pre-study blood work

Exclusion Criteria:

• have a history of substance dependence or abuse within the last 3 months
• have a concomitant major unstable medical illness, cardiac pacemaker or implanted medication pump
• have active suicidal intent
• are pregnant
• have a lifetime MINI diagnosis of bipolar I or II disorder, schizophrenia, schizoaffective disorder, schizophreniform, delusional disorder, or current psychotic symptoms
• have a MINI diagnosis of obsessive-compulsive disorder, post-traumatic stress disorder (current or within the last year), anxiety disorder (generalized anxiety disorder, social anxiety disorder, panic disorder), or dysthymia assessed by a study investigator to be primary and causing greater impairment than MDD