rTMS for Obsessive-Compulsive Disorder

(BOSS-OCD Trial)

Overseen By Nina E. Bahl, MSc

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Centre for Addiction and Mental Health

Must be taking: SSRIs

Must not be taking: Benzodiazepines, Anticonvulsants

Disqualifiers: Substance use disorder, Seizures, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 30

Duration: 6 weeks

48 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores a new method to help individuals with obsessive-compulsive disorder (OCD) using repetitive transcranial magnetic stimulation (rTMS), which employs magnets to stimulate specific brain areas. The researchers aim to determine if a personalized approach, guided by brain activity, is more effective than the standard method. This includes a treatment called Brain-Oscillation Synchronized Stimulation of the DMPFC. It targets individuals with OCD who have not found success with previous treatments like therapy or medication and are fluent in English. Participants should not have certain medical conditions, such as a history of seizures or metal implants.

As an unphased trial, this study provides a unique opportunity to contribute to groundbreaking research that could lead to new treatment options for OCD.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you must not have started or increased any psychotropic medications in the 4 weeks before screening. If you take more than 2mg of lorazepam or any anticonvulsant medication, you may not be eligible.

What prior data suggests that this rTMS technique is safe for OCD?

Research has shown that repetitive transcranial magnetic stimulation (rTMS) is a safe and non-invasive treatment. It uses magnetic fields to stimulate nerve cells in the brain. Studies have found that patients generally tolerate rTMS well. Most people experience only mild side effects like headaches or scalp discomfort, which usually resolve quickly.

Early research suggests that personalized, EEG-triggered rTMS is also safe. This type of rTMS targets specific brain patterns to enhance effectiveness. As this trial explores new applications of rTMS, researchers are closely monitoring safety. However, since rTMS is already used to treat other conditions, its overall safety record remains reassuring. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the treatment for Obsessive-Compulsive Disorder (OCD) using Brain-Oscillation Synchronized Stimulation of the DMPFC because it offers a novel approach compared to traditional options like SSRIs and CBT. Unlike standard treatments, this method uses personalized, EEG-triggered repetitive Transcranial Magnetic Stimulation (rTMS), which precisely targets brain activity patterns. This EEG synchronization allows for more tailored intervention, potentially enhancing effectiveness and reducing side effects. By directly modulating brain oscillations linked to OCD, this technique promises faster and more specific relief for patients.

What evidence suggests that this trial's treatments could be effective for OCD?

Research has shown that repetitive transcranial magnetic stimulation (rTMS) can help people with Obsessive-Compulsive Disorder (OCD). This treatment uses magnetic fields to stimulate specific brain areas, such as the dorsomedial prefrontal cortex, potentially reducing OCD symptoms. In this trial, participants will receive either a personalized, EEG-triggered rTMS or a non-personalized, non-EEG-triggered rTMS. Studies have found the personalized approach promising, as it adjusts to an individual's brain activity and might work better than the standard method. This personalized approach aims to more effectively target and improve OCD symptoms by matching the brain's natural rhythms. ^{1 2 3 4 6}

Who Is on the Research Team?

Brigitte Zrenner, MD

Principal Investigator

Centre for Addiction and Mental Health

Are You a Good Fit for This Trial?

This trial is for adults aged 18-65 with primary OCD that hasn't improved after therapy or an SSRI. Participants must have a Y-BOCS score >20, speak English fluently, and not be on new psychotropics within the last month. Excluded are those with TMS contraindications like metal implants, pacemakers, seizure history, substance use disorders (except nicotine/caffeine), or serious medical conditions.

Inclusion Criteria

Do not meet criteria for substance use disorder as determined by the MINI (with the exception of nicotine and caffeine)

Have a Y-BOCS score >20

Are fluent in the English language (spoken, written, reading)

Exclusion Criteria

Have any contraindications to TMS as determined by the Transcranial Magnetic Stimulation Adult Safety Screen (TASS) questionnaire

Are pregnant or breast feeding

Have any metal implants or dentures

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive EEG-triggered or non-EEG triggered rTMS treatment for OCD

6 weeks

30 sessions (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

1 week

What Are the Treatments Tested in This Trial?

Interventions

• Brain-Oscillation Synchronized Stimulation of the DMPFC

Trial Overview The study tests whether personalized EEG-triggered rTMS is more effective than standard non-EEG triggered rTMS when applied to the dorsomedial prefrontal cortex in treating refractory OCD. It also looks at changes in neurophysiological markers associated with these treatments.

How Is the Trial Designed?

Group I: Personalized, EEG-triggered rTMS Experimental Treatment 1 Intervention

Group II: Non-personalized, non-EEG triggered rTMS Active Control 1 Intervention

Who Is Running the Clinical Trial?

Centre for Addiction and Mental Health

Lead Sponsor

Trials

388

Recruited

84,200+

Published Research Related to This Trial

In a study involving 61 treatment-refractory OCD patients, all three rTMS protocols combined with exposure and response prevention (ERP) led to significant reductions in OCD symptoms, with a response rate of 57.4%.

Both high-frequency rTMS to the left dorsolateral prefrontal cortex and the left pre-supplementary motor area resulted in decreased activation in brain areas related to planning and error processing, which correlated with symptom improvement, although no significant differences in symptom reduction were found between the different rTMS groups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

TMS-induced plasticity improving cognitive control in OCD I: Clinical and neuroimaging outcomes from a randomised trial of rTMS for OCD. Fitzsimmons, SMDD., Postma, T., van Campen, AD., et al.[2023]

In a study involving 20 patients with treatment-resistant obsessive-compulsive disorder, sequential low-frequency rTMS targeting the right dorsolateral prefrontal cortex and supplementary motor area showed no significant therapeutic effect compared to sham treatment over 10 sessions.

Despite the lack of efficacy in reducing obsessive-compulsive symptoms, rTMS was found to be a safe treatment method, with no significant changes in cognitive function observed.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A randomized controlled study of sequentially applied repetitive transcranial magnetic stimulation in obsessive-compulsive disorder. Kang, JI., Kim, CH., Namkoong, K., et al.[2019]

In a double-blind study involving 18 subjects with treatment-resistant OCD, repetitive transcranial magnetic stimulation (rTMS) did not show significant efficacy compared to sham treatment after 10 sessions.

After extending to 20 sessions, rTMS resulted in a significant reduction in OCD symptoms, but this effect was not maintained when accounting for depression, indicating limited effectiveness for OCD treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Repetitive transcranial magnetic stimulation for the treatment of obsessive compulsive disorder: a double-blind controlled investigation. Sachdev, PS., Loo, CK., Mitchell, PB., et al.[2007]

In a randomized sham-controlled study involving 21 medication-resistant OCD patients, 67% of those receiving active rTMS to the supplementary motor area showed a significant response, compared to only 22% in the sham group, indicating the efficacy of rTMS in reducing OCD symptoms.

Patients who underwent 8 weeks of active rTMS experienced a substantial improvement in their OCD symptoms, with scores on the Yale-Brown Obsessive Compulsive Scale decreasing from an average of 28.2 to 14.5, suggesting that rTMS may normalize cortical hyper-excitability associated with OCD.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Randomized sham-controlled trial of repetitive transcranial magnetic stimulation in treatment-resistant obsessive-compulsive disorder. Mantovani, A., Simpson, HB., Fallon, BA., et al.[2021]

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT06942559

Brain-Oscillation Synchronized Stimulation of the DMPFC The study aims to compare the clinical effects of EEG-triggered, personalized rTMS (i.e., experimental arm) in the treatment of OCD to those of non-EEG ...

2. withpower.com withpower.com/trial/phase-obsessive-compulsive-disorder-2025-e599b

rTMS for Obsessive-Compulsive Disorder (BOSS-OCD Trial) Trial Overview The study tests whether personalized EEG-triggered rTMS is more effective than standard non-EEG triggered rTMS when applied to the dorsomedial ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6047114/

Transcranial magnetic stimulation in obsessive-compulsive ... TMS is a non-invasive brain stimulation technique that has shown promise as an adjunct treatment for the symptoms of Obsessive-Compulsive Disorder (OCD).

4. sciencedirect.com sciencedirect.com/science/article/pii/S027858462400215X

Transcranial magnetic stimulation for obsessive ... We systematically reviewed randomised controlled trials (RCTs) applying TMS in obsessive compulsive disorder (OCD) and post-traumatic stress disorder (PTSD)

5. researchgate.net researchgate.net/publication/394479361_Obsessive-Compulsive_Disorder

Obsessive-Compulsive Disorder Emerging neurostimulation therapies, encompassing both noninvasive and invasive techniques, offer promising alternatives for managing OCD.

6. biologicalpsychiatryjournal.com biologicalpsychiatryjournal.com/article/S0006-3223(23)01589-5/fulltext

Closed-Loop Brain Stimulation Here, we elucidate the possibility and provide first evidence that repetitive TMS (rTMS) synchronized with specific brain states induces LTP-/ ...