The goal of this clinical trial is to test whether an accelerated deep Transcranial Magnetic Stimulation (dTMS) protocol can reduce depressive symptoms in older adults (ages 60-85) with Major Depressive Disorder (MDD) who have not tolerated or responded to antidepressant medications. The study will evaluate whether accelerated dTMS administered over 5 consecutive days is safe and well-tolerated in this population, and whether it produces greater reductions in depressive symptoms compared to placebo stimulation.

This study will investigate the effects of an accelerated intermittent theta burst protocol (a-iTBS) using the H7 deep Transcranial Magnetic Stimulation (dTMS) coil to target the anterior cingulate cortex (ACC) in older adults (aged 60-85) with Major Depressive Disorder (MDD). Twenty-four older adults with treatment-resistant MDD will participate in a single site, double-blind, randomized sham-controlled trial using an accelerated schedule of multiple dTMS sessions per day for 5 consecutive days. The primary goal of the study is to establish the feasibility of an accelerated aiTBS protocol of the ACC in older adults with treatment resistant depression, and to obtain preliminary evidence of treatment efficacy.

Inclusion Criteria:

• are between 60- 85 years old (on the day of randomization)
• have been diagnosed with DSM5 Major Depressive Disorder, with the current episode longer than 4 weeks but less than 5 years
• did not respond to/did not tolerate, or failed to achieve remission with at least one antidepressant trial of 8 week minimum duration
• are willing to provide informed consent
• are able to follow the treatment schedule
• are stable on medications for 2 months and are not expected to change medication during the entire study period (if they are taking medications)
• have a satisfactory safety screening questionnaire for TMS

Exclusion Criteria:

• have a metal plate in your head (such as an ear implant, implanted brain stimulators, aneurysm clips). Dental devices and implants that are non-magnetic are safe
• have known increased pressure or a history of increased pressure in their brain, which may increase their risk for having seizures
• have a cardiac pacemaker
• have an implanted medication pump
• have a central venous line
• have a history of any psychotic disorder, bipolar disorder, eating disorder, obsessive compulsive disorder, post-traumatic stress disorder, or dementia
• have a history of substance abuse in the last 6 months
• have a history of stroke or other brain lesions
• have a personal history of epilepsy
• have a family history of epilepsy
• are a pregnant or breast-feeding woman
• have a history of abnormal MRI of the brain
• have untreated hypo- or hyper-thyroidism
• have unstable medical condition(s)
• have any other known contraindications to TMS
• are on unstable doses of any psychotropic medication such as - antidepressants, antipsychotic, mood stabilizers or memory enhancing medications
• require daily doses of benzodiazepines or hypnotics within two weeks of randomization