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Not yet taking people in United StatesPhase 1/2

Sonication-based OCD Neurosurgical Intervention Via Capsulotomy

Key facts

Who runs it
Brigham and Women's Hospital
Where
Boston and Palo Alto, United StatesSee the 2 sites
Trial code
Status
Not yet recruiting
Phase
Phase 1/2
People taking part
66 people, planned
Started
Aug 2026
Expected to end
Aug 2032
Type of study
Interventional, 2 groupsOne group gets an existing treatment, for comparison.
Treatments tested
  • ExAblate MR-guided Focused Ultrasound Bilateral Anterior Capsulotomy
Record updated
25 February 2026

Who can take part

Age
25 years to 64 years
Sex
Women and men
Healthy volunteers
Cannot take part

The registry criteria, word for word

Show all 26 criteriaShow less

Who can take part

  • 25-64 years, inclusive
  • Patients who are able and willing to give consent and able to attend study visits, as determined by both study psychiatrist and the surgeon
  • DSM-5 diagnosis of Obsessive-Compulsive Disorder (OCD), at least 5-year illness history, with a minimum score of 28 on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) for stage I and a minimum score of 24 on Y-BOCS for stage II
  • Medication-refractoriness as determined by an adequate dose and duration of standard psychiatric treatments (including psychotherapy and/or pharmacology) as determined by psychiatrists associated with the study. Including specifically:; Failed adequate trial of three or more medications accepted as first line in the treatment of OCD such as selective serotonin reuptake inhibitors (SSRIs, e.g. fluoxetine, citalopram), selective serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs, e.g. clomipramine) or other antidepressants at the maximal tolerated dose. Adequate maximal doses and minimal duration of these medication are listed in Table 2 below; Attempted augmentation, if tolerated, by at least two medications known to be second line treatments for OCD such as clonazepam, haloperidol, risperidone, olanzapine, gabapentin; An adequate trial of cognitive behavioral therapy (CBT) delivered by a therapist experienced in treating OCD. Criteria for an adequate CBT are listed in Table 3 below; In stage II patients that cannot tolerate pharmacotherapy or participate in psychotherapy will be included in the study
  • A consistent dose of all medications in the 30 days prior to study entry
  • Able to communicate sensations during the ExAblate MRgFUS treatment

Who cannot take part

  • Lifetime diagnosis of psychosis or bipolar disorder or presence of suicidality (as measured by a score >=2, item 9 of the BDI or high suicidal risk measured by the Columbia Suicide Severity Rating Scale (C-SSRS)). Subjects with stable, chronic anxiety or depressive disorders may be included provided their medications have been stable for at least 3 months prior to study entry and if deemed appropriately managed by the site psychiatrist
  • Severely impaired renal function (estimated glomerular filtration rate < 30ml/min/1.73 m2) or receiving dialysis
  • Receiving anticoagulant (e.g. warfarin) or antiplatelet (e.g. aspirin) therapy within one week of focused ultrasound procedure or drugs known to increase risk of hemorrhage (e.g. Avastin) within one month of focused ultrasound procedure. Receiving medications or supplements that increase the risk of bleeding such as NSAIDS, Ginko Baloba and Ginseng within one week of focused ultrasound procedure
  • Presence of significant cognitive impairment (as measured by a score <25 on the mini-mental state examination, MMSE)
  • DSM-5 diagnosis of substance use disorder (SUD) within the past 6 months
  • Patients with unstable cardiac status [e.g. unstable angina pectoris on medication; patients' medication (other than diuretic); patients on anti-arrhythmic drugs; severe hypertension (diastolic BP > 100 on medication)]
  • Cerebrovascular disease (e.g. CVA within 6 months), history of intracranial hemorrhage or intracranial aneurysms requiring treatment or arterial venous malformations (AVMs) requiring treatment
  • Patients with brain tumors, epilepsy, neurodegenerative disease or any other major neurological disorder
  • Patients with standard contraindications for MR imaging such as non-MRI compatible implanted metallic devices including cardiac pacemakers, size limitations, etc
  • Known intolerance or allergies to MRI contrast agent (e.g. Gadolinium or Magnevist) including advanced kidney disease
  • Current medical condition resulting in abnormal bleeding and/or coagulopathy
  • Life-threatening systemic disease that include and not limited to the following will be excluded from the study participation: HIV, liver failure, blood dyscrasias, etc
  • Laboratory biochemical evidence of abnormal bleeding and/or coagulopathy, including risk factors for intraoperative or postoperative bleeding (platelet count less than 100,000 per cubic millimeter or abnormal INR)
  • Currently pregnant (as determined by history and serum HCG) or lactating
  • Untreated, uncontrolled sleep apnea
  • Subjects who weigh more than the upper weight limit of the MR scanner table and who cannot fit into the MR scanner
  • An Overall Skull Density Ratio of less than 0.40 as calculated from the screening CT
  • Individuals who are not able or willing to tolerate the required prolonged stationary supine position during treatment
  • Are participating or have participated in another clinical trial in the last 30 days
  • Patients unable to communicate with the investigator and staff

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

  • Are you between 25 and 64 years old?

Where in United States

  • Brigham and Women's HospitalBoston, United StatesNot yet recruiting
  • Stanford UniversityPalo Alto, United StatesContact: Bhati Mahendra, MDNot yet recruiting

About the trial

What the trial wants to find out

The goal of this clinical trial is to determine if ExAblate MR-guided Focused Ultrasound (MRgFUS) bilateral anterior capsulotomy can be used safely and effectively to relieve symptoms of moderate to severe obsessive compulsive disorder (OCD) in individuals who have not benefited from psychotherapy and medications.

Read full original descriptionShow less

The main questions it aims to answer are:

1. Can ExAblate MRgFUS capsulotomy be safely delivered to individuals suffering from treatment-refractory OCD through an intact skull with a risk and side-effect profile that is comparable to other neurosurgical approaches for capsulotomy? 2. Will ExAblate MRgFUS capsulotomy result in improvement in clinical symptoms and quality of life metrics that are similar to those seen with other surgical approaches for capsulotomy?

In the first stage of the study, participants with severe, treatment resistant OCD (n=10) will be recruited in two centers (Harvard and Stanford) and treated with best medical care (BMT) for 6 months. Thereafter, they will receive the ExAblate MRgFUS procedure and then another BMT for 12 months. In the second stage of the study, participants with moderate to severe OCD (n=56) will be recruited in a multi-center study and treated with BMT plus real or sham MRgFUS for 12 months. Thereafter, those who received sham MRgFUS and did not improve will receive real MRgFUS and then treated with BMT for another 12 months.

The 2 groups in the trial

  • Active FUSExisting treatment, for comparison

    The treatment volume and plan will be defined by the neurosurgeon. The ExAblate MRgFUS system will automatically compute the number of sonications, and the (per sonication spot) phase and amplitude corrections necessary for the system to produce a focal spot at each of the desired locations. The target selected for this study is the anterior limb of the internal capsule (ALIC). The target will be approximately 7-10mm rostral to the anterior edge of the anterior commissure, in the ventral part of the ALIC. A central point in the targeted area will be targeted with a low dose, sub-lethal energy level sonication to confirm the targeting accuracy on the MR images. Focal point position and/or transducer location will be adjusted as necessary.

    Treatment: ExAblate MR-guided Focused Ultrasound Bilateral Anterior Capsulotomy

  • Sham FUSSham treatment, for comparison

    The sham procedure will be identical in planning and execution to the ExAblate procedure with the only exception being that the energy output will be 0 for the sham-treated subjects. To perform the sham treatment, the sonication will be performed with energy output disabled. For sham subjects, the physician will interact with a subject in a similar manner and for a similar duration to simulate an actual procedure. When possible, the treating physician may determine a sonication (treatment) time for sham subjects to be similar to that which is occurring in the ExAblate procedure to maintain consistency between treatment arms. It should be noted that all treatment times of both treatment arms will be captured in the study CRF.

    Treatment: ExAblate MR-guided Focused Ultrasound Bilateral Anterior Capsulotomy

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov.
Official title
ExAblate MR-guided Focused Ultrasound Bilateral Anterior Capsulotomy for Treatment of Obsessive-Compulsive Disorder
Fit questions
Built from NCT06131502, who can take part
Record updated
25 February 2026