Summary: Stanford Neuromodulation Therapy (SNT) Trial

Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial

Authors

Eleanor J. Cole, Ph.D., Angela L. Phillips, Ph.D., Brandon S. Bentzley, M.D., Ph.D., et al.

Key Takeaways

• Remission: 79% of participants in the active treatment group met criteria for remission (MADRS score ≤10) at the primary endpoint.
• Duration: The treatment protocol was administered over a 5-day period.
• Durability: Statistically significant improvements in depressive symptoms were maintained at the 4-week follow-up.
• Safety Profile: The protocol was well tolerated; no serious adverse events or evidence of cognitive decline were reported.
• Targeting: The protocol utilizes functional MRI (fMRI) to identify individual-specific coordinates for stimulation.

Why This Matters for SAINT

This study evaluated the efficacy and safety of Stanford Neuromodulation Therapy (SNT), also referred to as SAINT (Stanford Accelerated Intelligent Neuromodulation Therapy), through a double-blind, sham-controlled, randomized trial. The trial was designed to assess whether an accelerated, fMRI-guided intermittent theta-burst stimulation (iTBS) protocol could reduce depressive symptoms in patients with treatment-resistant depression (TRD).

1. Evaluation of Accelerated iTBS Schedule

The study assessed a compressed schedule consisting of 10 iTBS sessions per day (1,800 pulses per session, 50-minute inter-session intervals) over 5 consecutive days. The results indicate that this high-dose, accelerated delivery is a feasible and safe alternative to standard TMS protocols, which typically span 6 to 8 weeks.

2. Functional Connectivity-Based Targeting

The SAINT protocol utilizes personalized fMRI mapping to guide the stimulation. The stimulation targets the specific subregion of the left dorsolateral prefrontal cortex (L-DLPFC) that shows the strongest functional anticorrelation with the subgenual anterior cingulate cortex (sgACC). This methodological approach is intended to account for individual neuroanatomical variation.

3. Application of Spaced Learning Theory

The protocol’s design—specifically the 50-minute intervals between 10-minute stimulation blocks—is based on the principle of spaced learning. This interval is intended to optimize the induction of long-term potentiation (LTP) and neural plasticity within the targeted circuits. The 79% remission rate observed in the active group suggests that this delivery method effectively modulates circuits involved in mood regulation.

4. Outcomes for Treatment-Resistant Depression (TRD)

The trial demonstrates that, in a cohort of patients who have failed multiple pharmacological interventions, an accelerated, personalized neuromodulation protocol can achieve a significant reduction in symptom severity. These findings provide evidence for the efficacy of the protocol in a controlled clinical setting.

Expert Perspective

“In a rigorously controlled, treatment-resistant cohort, SAINT delivered rapid, outsized antidepressant effects—with remission rates approaching 80% and large effect sizes that far exceeded sham. This trial reframes the ceiling of neuromodulation efficacy, demonstrating that meaningful remission in treatment-resistant depression can be both rapid and robust.” – Brandon Bentzley, MD, PhD.

Study Overview and Methodology

The study was a double-blind, sham-controlled, randomized controlled trial (RCT) designed to investigate the efficacy of SAINT compared to a placebo (sham) stimulation for the treatment of moderate-to-severe TRD.

Participants: 29 adults with treatment-resistant major depressive disorder were randomized. Participants had histories of non-response to multiple standard treatments and were experiencing depressive episodes of significant duration.

• Active Group: Received the SAINT protocol: 10 daily sessions of fMRI-guided iTBS (90,000 total pulses) for 5 days.
• Sham Group: Received a treatment that mimicked the acoustic and sensory experience of TMS using a sham coil that delivered no magnetic stimulation to the cortex.

Follow-up: The primary endpoint was reached 5 days post-treatment, with longitudinal follow-up conducted over 4 weeks to assess the durability of the clinical response.

Key Findings

• Remission Rates: At the primary endpoint, 79% (11 out of 14) of the active group achieved remission, compared to 13% (2 out of 15) in the sham group.
• Response Time: Clinical improvement was observed within the 5-day treatment window, significantly shorter than the 6-to-8-week timeline typical of standard iTBS or SSRI interventions.
• Safety and Tolerability: No serious adverse events were reported. There were no observed negative effects on cognitive function or memory. The most common side effects were fatigue and localized scalp discomfort.
• Clinical Efficacy: SAINT demonstrated a high effect size in a population that had previously not achieved adequate response from conventional antidepressant therapies.

Frequently Asked Questions

1. What is the safety profile of SAINT? The trial data indicates that SAINT is safe and well-tolerated. Reported side effects were mild and transient, primarily consisting of scalp discomfort and fatigue. Standardized testing showed no impairment in memory or cognitive performance following the high-dose stimulation.

2. What is the observed durability of the treatment? The study monitored participants for 4 weeks post-treatment. During this period, the majority of participants in the active group who achieved remission maintained their clinical status. Further research is required to determine the long-term durability and the potential need for maintenance therapy.

3. How does SAINT differ from standard TMS? SAINT differs from standard TMS in two primary technical areas: the condensation of the treatment schedule (5 days vs. 6 weeks) and the use of individualized fMRI-guided targeting. While standard TMS uses a uniform targeting method for all patients, SAINT uses functional connectivity mapping to locate a patient-specific stimulation site.

Citation & Original Source

Cole, E. J., Phillips, A. L., Bentzley, B. S., Wheeler, A. R., Nejad, R., Pankow, H., Hoffman, K., Guerin, J., Choi, J. H., Harris, J. J., Bergen-Ciccarelli, N. K., Soneji, N., Pisani, S. L., Conti-Vock, A. K., Tellez-Prado, M., Prasad, R., Stimpson, K. J., Bishop, J. H., Aratake, T., . . . Williams, N. R. (2022). Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial. The American Journal of Psychiatry, 179(2), 132–141. https://doi.org/10.1176/appi.ajp.2021.20101429

Read the Full Study Here: The American Journal of Psychiatry