Pilot Accelerated Theta Burst in Treatment-Resistant Bipolar Depression

Inclusion Criteria: * Male or female, 18 to 80 years of age. * Able to provide informed consent. * Diagnosed with Bipolar Disorder and currently experiencing a Major Depressive Episode (MDE). * Meet the threshold on the total MADRS score of \>/=20 at baseline. * In good general health, as ascertained by medical history. * If female, a status of non-childbearing potential or use of an acceptable form of birth control. * History of rTMS failure with FDA approved rTMS parameters is permitted. Exclusion Criteria: * Female of childbearing potential who is not willing to use one of the specified forms of birth control during the study. * Female that is pregnant or breastfeeding. * Female with a positive pregnancy test at participation. * Total MADRS score of \< 20 at study entry. * Current diagnosis of a Substance Use Disorder (Abuse or Dependence, as defined by DSM-IV-TR), with the exception of nicotine dependence. * Current diagnosis of Axis I disorders other than Dysthymic Disorder, Generalized Anxiety Disorder, Social Anxiety Disorder, Panic Disorder, Agoraphobia, or Specific Phobia (unless one of these is comorbid and clinically unstable, and/or the focus of the participant's treatment for the past six months or more). * History of schizophrenia or schizoaffective disorders, or any history of psychotic symptoms in the current or previous depressive episodes. * Any Axis I or Axis II Disorder, which at screening is clinically predominant to their bipolar depression or has been predominant to their bipolar depression at any time within six months prior to screening. * Considered at significant risk for suicide during the course of the study. * Has a clinically significant abnormality on the screening examination that might affect safety, study participation, or confound interpretation of study results. * Participation in any clinical trial with an investigational drug or device within the past month or concurrent to study participation. * Any current or past history of any physical condition which in the investigator's opinion might put the subject at risk or interfere with study results interpretation. * History of positive screening urine test for drugs of abuse at screening: cocaine, amphetamines, barbiturates, opiates. * Current (or chronic) use of opiates. * History of epilepsy. * History of shrapnel or metal in the head or skull. * History of cardiovascular disease or cardiac event. * History of OCD. * History of autism spectrum disorder. * Current psychosis * Any change in medication of which the study PI is not aware of.