An interventional study of Device: Stimulation-ON and Device: Stimulation-OFF in Bipolar II Disorder and Bipolar II Disorder, Most Recent Episode Major Depressive, sponsored by Andrew Krystal. Recruiting at 1 site in United States. Open to participants aged 22 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-08-17.
Sponsored by Andrew Krystal · Not applicable, Interventional, and Treatment
Neurons are specialized types of cells that are responsible for carrying out the functions of the brain. Neurons communicate with electrical signals. In diseases such as major depression this electrical communication can go awry. One way to change brain function is using electrical stimulation to help alter the communication between groups of neurons in the brain.
The purpose of this study is to test a personalized approach to brain stimulation as an intervention for bipolar depression The study researchers will use a surgically implanted device to measure each individual's brain activity related to his/her depression. The researchers will then use small electrical impulses to alter that brain activity and measure whether these changes help reduce depression symptoms. This study is intended for patients with major depression whose symptoms have not been adequately treated with currently available therapies.
The device used in this study is called the NeuroPace Responsive Neurostimulation (RNS) System. It is currently FDA approved to treat patients with epilepsy. The study will test whether personalized responsive neurostimulation can safely and effectively treat bipolar depression.
This is a single-center 3-stage feasibility study of personalized closed-loop stimulation for treatment resistant Bipolar Depression. Depending on participant's results at each stage, he/she might not be eligible to proceed to all 3 stages.
Stage 1 of the study will involve surgically implanting small, thin electrodes in brain regions that regulate depression in order to identify personalized treatment sites. The researchers will test stimulation in the different brain regions and their effect on bipolar depression symptoms. The electrodes will be surgically removed at the end of Stage 1.
Stage 2 will involve a second brain surgery to implant the NeuroPace RNS® System. Researchers will use information from Stage 1 to decide where to implant the electrodes of the RNS System. Over the next \~4-18 months, participants will have regular study visits in the clinic where the researchers will determine a personalized brain activity pattern that correlates with depression symptoms and can be paired with stimulation to improve depression symptoms.
Stage 3 will be 36-40 weeks long and will involve turning ON and OFF the intervention to test its effectiveness. Participants will have a variable start time for Stage 3 to facilitate blinding of both patients and clinician raters. This variable time will be randomized from conditions of 0 days, 2 weeks, or 4 weeks (during which time participants will remain on optimized closed-loop stimulation). Each participant will have three 12-week periods: closed-loop stimulation (intervention), open-loop/fixed intermittent stimulation (active control), and sham (passive control), order counterbalanced.
At the end of this stage the participant can choose to continue with long-term follow-up or have the RNS System surgically removed.
1,601 studies on the registry are indexed under Bipolar Disorder; 254 are open to participants now.
This study's planned enrollment of 10 is below the median of 64 across 1,223 interventional studies indexed under Bipolar Disorder.
Browse Bipolar Disorder studies →Andrew Krystal is the lead sponsor of 3 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
This is a crossover trial. Each patient will receive 12 wks of stimulation ON (arm 1), stimulation OFF (arm 2), and Stimulation ON Active Control (fixed intermittent) (arm 3) in random order.
Device: Device: Stimulation-ON
This is a crossover trial. Each patient will receive 12 wks of stimulation ON (arm 1), stimulation OFF (arm 2), and Stimulation ON Active Control (fixed intermittent) (arm 3) in random order.
Device: Device: Stimulation-OFF
This is a crossover trial. Each patient will receive 12 wks of stimulation ON (arm 1), stimulation OFF (arm 2), and Stimulation ON Active Control (fixed intermittent) (arm 3) in random order.
Device: Device: Stimulation -ON Active Control
Active neurostimulation from the NeuroPace RNS® System triggered by a biomarker
No neurostimulation from the NeuroPace RNS® System
Active neurostimulation from the NeuroPace RNS® System triggered with a fixed duty cycle
Change in Montgomery-Asberg Depression Rating Scale (MADRS) score
Effect size comparing closed-loop stimulation, open-loop (fixed intermittent) stimulation, and sham stimulation (MADRS score before and after each treatment period of the crossover). Higher MADRS score indicates more severe depression; the overall score ranges from 0 to 60.
Time frame: Administered twice at baseline and every 2 weeks for the 36-40 weeks of Stage 3
Change in Hamilton Depression Rating Scale (HAMD-17) score
Effect size comparing closed-loop stimulation, open-loop (fixed intermittent) stimulation, and sham stimulation (HAMD-17 score before and after each treatment period of the crossover). The score for Hamilton Depression Rating Scale ranges from 0-50, with a higher score indicating more severe depression.
Time frame: Administered at baseline and every 4 weeks for the 36-40 weeks of Stage 3
Change in the Inventory of Depressive Symptomatology Self-Report (IDS-SR) score
Effect size comparing closed-loop stimulation, open-loop (fixed intermittent) stimulation, and sham stimulation (IDS-SR score before and after each treatment period of the crossover). The scores range from 0 to 27, with higher scores indicating more depressive symptoms.
Time frame: Administered at baseline and every 4 weeks for the 36-40 weeks of Stage 3
Daily stimulation events
Number of daily stimulation events
Time frame: Up to 24 weeks
Stimulation duration
Cumulative stimulation duration per day
Time frame: Up to 24 weeks
Stimulation site identification
The number of patients that move from Stage 1 to Stage 2 (stimulation site identified that acutely improved symptoms)
Time frame: Decision made in the 1-3 months following Stage 1
Biomarker identification in Stage 1
Number of patients in whom we can identify a neural biomarker
Time frame: Decision made in the 1-3 months following Stage 1
Number of patients who had viable biomarker(s) identified in Stage 2
Number of patients in whom we can utilize the biomarker to drive stimulation events using the RNS® System
Time frame: Once at the end of Stage 2, ranging from 4-15 months
Number and severity of adverse events
The number and type of serious adverse events that occur in comparison to comparable deep brain stimulation trials
Time frame: Through study completion, average of 2.5-3 years
Plan to share: No
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