Trial results for a pilot study investigating the Safe and Sound Protocol (SSP) for Post Traumatic Stress Disorder (PTSD) were posted on ClinicalTrials.gov on 2025-09-05, showing a mean reduction of 9.9 points in PTSD symptoms for the SSP plus psychotherapy group.
Background
Post Traumatic Stress Disorder (PTSD) is a mental health condition that can arise after experiencing or witnessing a traumatic event. Anxiety often co-occurs with PTSD, impacting daily functioning. The Safe and Sound Protocol (SSP) is a passive acoustic intervention designed as a "neural exercise" to promote efficient regulation of autonomic state. Previous research has indicated that SSP can improve autonomic function, auditory hypersensitivities, and emotion regulation in individuals with Autism Spectrum Disorders. This observational pilot study aimed to establish methods for a future randomized controlled trial to test the utility of SSP for trauma treatment.
Trial design
This completed observational pilot study, designated as Phase NA, enrolled 45 participants. The study investigated individuals with Post Traumatic Stress Disorder and Anxiety. The trial examined outcomes in a group receiving Psychotherapy + SSP compared to a group receiving Psychotherapy (Treatment as Usual). The study's purpose was to establish methods for an upcoming randomized controlled trial to test the utility of the SSP for trauma treatment.
Key results
The trial reported several key measurements related to changes from baseline:
- Change From Baseline in Post Traumatic Stress Disorder Symptoms (score on a scale):
- For the Psychotherapy + SSP group, the mean change was -9.9 (Standard Deviation 11.1).
- For the Psychotherapy (Treatment as Usual) group, the mean change was -2.3 (Standard Deviation 12.2).
- Change From Baseline in Anxiety Symptoms (score on a scale):
- For the Psychotherapy + SSP group, the mean change was -1.9 (Standard Deviation 3.5).
- For the Psychotherapy (Treatment as Usual) group, the mean change was -0.8 (Standard Deviation 3.4).
- Change From Baseline in Self-reported Disruption of Autonomic Reactivity (score on a scale):
- For the Psychotherapy + SSP group, the mean change was -1.7 (Standard Deviation 5.5).
- For the Psychotherapy (Treatment as Usual) group, the mean change was -0.1 (Standard Deviation 5.2).
- Change From Baseline in Mean Heart Period During Posture Shifts [SSP Arm Only] (milliseconds):
- For the Psychotherapy + SSP group, the mean change was -99.8 (Standard Deviation 117.0).
- For the Psychotherapy + SSP group, the mean change was -90.0 (Standard Deviation 134.0).
- For the Psychotherapy + SSP group, the mean change was -70.2 (Standard Deviation 142.).
- Change From Baseline in Respiratory Sinus Arrhythmia (RSA) During Posture Shifts [SSP Arm Only] (ln[milliseconds]^2):
- For the Psychotherapy + SSP group, the mean change was -.35 (Standard Deviation 1.00).
- For the Psychotherapy + SSP group, the mean change was -.43 (Standard Deviation 1.44).
- For the Psychotherapy + SSP group, the mean change was -.04 (Standard Deviation 1.33).
What this means
The posted results from this pilot study suggest that the Safe and Sound Protocol (SSP) when combined with psychotherapy may lead to greater reductions in symptoms for individuals with Post Traumatic Stress Disorder and Anxiety. Specifically, the Psychotherapy + SSP group showed a larger mean decrease in PTSD symptoms (-9.9 points) compared to the Psychotherapy (Treatment as Usual) group (-2.3 points). Similar trends were observed for anxiety symptoms and self-reported disruption of autonomic reactivity. Additionally, the SSP arm showed changes in physiological measures like mean heart period and respiratory sinus arrhythmia. As a pilot study, these findings provide preliminary data to inform the design of future randomized controlled trials to further evaluate the efficacy of SSP for trauma treatment.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study "The Effects of the Safe and Sound Protocol on PTSD Symptoms and Anxiety" were posted on 2025-09-05 on clinicaltrials.gov.