Trial Outcomes & Findings for Oxytocin to Treat PTSD (NCT NCT04228289)
NCT ID: NCT04228289
Last Updated: 2026-03-11
Results Overview
Change in Post Traumatic Stress Disorder symptom severity as measured by Clinician Administered Post Traumatic Stress Disorder (PTSD) Scale (CAPS-5) for clinician-rated posttraumatic stress symptoms. The CAPS-5 is a 30-item structured interview. CAPS-5 total symptom severity score is calculated by summing severity scores for the 20 PTSD symptoms, each with severity scores ranging from 0-4. The overall total severity score for CAPS-5 ranges from 0-80, with lower scores representing better outcomes (less severe PTSD).
COMPLETED
PHASE2
180 participants
From baseline to of Treatment (10 weeks)
2026-03-11
Participant Flow
Participants were recruited through Veterans Administration (VA) clinics, VA clinician referrals, and flyers at designated VA and Community-Based Outpatient Clinic (CBOC) locations. Following preliminary eligibility screening, veterans completed private written informed and a baseline assessment. The baseline assessment included a battery of standardized self-report and interview measures. Enrollment occurred from January 2021 through September 2024.
Participants were 180 adult United States military veterans meeting diagnostic criteria for Post Traumatic Stress Disorder. Veterans who were taking psychotropic medications were required to be on a stable dose for 4 weeks before enrolling.
Participant milestones
| Measure |
Oxytocin
A 40-International Unit (IU) dose of intranasal oxytocin self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
Placebo
An identical intranasal placebo dose was self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
|---|---|---|
|
Overall Study
STARTED
|
92
|
88
|
|
Overall Study
COMPLETED
|
68
|
68
|
|
Overall Study
NOT COMPLETED
|
24
|
20
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Oxytocin to Treat PTSD
Baseline characteristics by cohort
| Measure |
Oxytocin
n=92 Participants
A 40-International Unit (IU) dose of intranasal oxytocin self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
Placebo
n=88 Participants
An identical intranasal placebo dose was self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
Total
n=180 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
43.6 years
STANDARD_DEVIATION 11.3 • n=9 Participants
|
46.6 years
STANDARD_DEVIATION 14.2 • n=9 Participants
|
45 years
STANDARD_DEVIATION 12.9 • n=18 Participants
|
|
Sex: Female, Male
Female
|
25 Participants
n=9 Participants
|
22 Participants
n=9 Participants
|
47 Participants
n=18 Participants
|
|
Sex: Female, Male
Male
|
67 Participants
n=9 Participants
|
66 Participants
n=9 Participants
|
133 Participants
n=18 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
14 Participants
n=9 Participants
|
9 Participants
n=9 Participants
|
23 Participants
n=18 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
78 Participants
n=9 Participants
|
78 Participants
n=9 Participants
|
156 Participants
n=18 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=9 Participants
|
1 Participants
n=9 Participants
|
1 Participants
n=18 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
2 Participants
n=9 Participants
|
0 Participants
n=9 Participants
|
2 Participants
n=18 Participants
|
|
Race (NIH/OMB)
Asian
|
1 Participants
n=9 Participants
|
0 Participants
n=9 Participants
|
1 Participants
n=18 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=9 Participants
|
0 Participants
n=9 Participants
|
0 Participants
n=18 Participants
|
|
Race (NIH/OMB)
Black or African American
|
21 Participants
n=9 Participants
|
16 Participants
n=9 Participants
|
37 Participants
n=18 Participants
|
|
Race (NIH/OMB)
White
|
62 Participants
n=9 Participants
|
65 Participants
n=9 Participants
|
127 Participants
n=18 Participants
|
|
Race (NIH/OMB)
More than one race
|
3 Participants
n=9 Participants
|
5 Participants
n=9 Participants
|
8 Participants
n=18 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
3 Participants
n=9 Participants
|
2 Participants
n=9 Participants
|
5 Participants
n=18 Participants
|
|
Region of Enrollment
United States
|
92 Participants
n=9 Participants
|
88 Participants
n=9 Participants
|
180 Participants
n=18 Participants
|
PRIMARY outcome
Timeframe: From baseline to of Treatment (10 weeks)Population: Analysis population includes participants who completed treatment.
Change in Post Traumatic Stress Disorder symptom severity as measured by Clinician Administered Post Traumatic Stress Disorder (PTSD) Scale (CAPS-5) for clinician-rated posttraumatic stress symptoms. The CAPS-5 is a 30-item structured interview. CAPS-5 total symptom severity score is calculated by summing severity scores for the 20 PTSD symptoms, each with severity scores ranging from 0-4. The overall total severity score for CAPS-5 ranges from 0-80, with lower scores representing better outcomes (less severe PTSD).
Outcome measures
| Measure |
Oxytocin
n=68 Participants
40 IU intranasal oxytocin
Oxytocin: 40 IU intranasal spray
|
Placebo
n=65 Participants
intranasal saline spray
Placebo: matching intranasal spray
|
|---|---|---|
|
Change in Post Traumatic Stress Disorder Symptom Severity - Clinician Rated
|
-10.1 units on a scale
Standard Deviation 11.8
|
-12 units on a scale
Standard Deviation 12.8
|
PRIMARY outcome
Timeframe: From baseline to end of Treatment (10 weeks)Population: Population analysis includes participants who completed the treatment phase.
Change in Post Traumatic Stress Disorder (PTSD) symptom severity as measured by the Posttraumatic Checklist for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition \[DSM-5\](PCL-5) for self-reported symptoms. The PCL-5 is a 20-item self-report measure that assesses the 20 symptoms of PTSD. The rating scale is 0-4 for each symptom/item, and overall scores range from 0-80, with lower scores representing better outcomes (less severe PTSD).
Outcome measures
| Measure |
Oxytocin
n=68 Participants
40 IU intranasal oxytocin
Oxytocin: 40 IU intranasal spray
|
Placebo
n=66 Participants
intranasal saline spray
Placebo: matching intranasal spray
|
|---|---|---|
|
Change in Post Traumatic Stress Disorder Symptom Severity - Self Report
|
-19.4 units on a scale
Standard Deviation 18
|
-25.2 units on a scale
Standard Deviation 18
|
Adverse Events
Oxytocin
Placebo
Serious adverse events
| Measure |
Oxytocin
n=92 participants at risk
A 40-International Unit (IU) dose of intranasal oxytocin self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
Placebo
n=88 participants at risk
An identical intranasal placebo dose was self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
|---|---|---|
|
Infections and infestations
Hospitalization from Bronchitis and Streptococcal Pharyngitis
|
1.1%
1/92 • Number of events 1 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
0.00%
0/88 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
Other adverse events
| Measure |
Oxytocin
n=92 participants at risk
A 40-International Unit (IU) dose of intranasal oxytocin self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
Placebo
n=88 participants at risk
An identical intranasal placebo dose was self-administered 30 minutes prior to the start of each weekly Prolonged Exposure therapy session.
All participants assigned to 10 weekly, 90-minute therapy sessions delivered by trained Masters or Doctoral-level clinicians consistent with the published manual.
|
|---|---|---|
|
Infections and infestations
Upper Respiratory Infection
|
13.0%
12/92 • Number of events 13 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
9.1%
8/88 • Number of events 8 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
|
Nervous system disorders
Headache
|
7.6%
7/92 • Number of events 8 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
6.8%
6/88 • Number of events 9 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
|
Musculoskeletal and connective tissue disorders
Knee Pain
|
6.5%
6/92 • Number of events 6 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
0.00%
0/88 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
|
Nervous system disorders
Migraine
|
5.4%
5/92 • Number of events 6 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
2.3%
2/88 • Number of events 2 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
|
Infections and infestations
COVID-19
|
2.2%
2/92 • Number of events 2 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
9.1%
8/88 • Number of events 8 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
|
Gastrointestinal disorders
Gastroenteritis
|
4.3%
4/92 • Number of events 4 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
5.7%
5/88 • Number of events 6 • From baseline through 10 week treatment phase and through 6 month follow up phase.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place