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Predicting Responses to PTSD Treatment With Iris and Cardiovascular Tests

Noradrenergic Biomarkers in PTSD: Precision Medicine & Mechanisms

Status
Active, not recruiting
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03539614
Acronym
PREDICT
Enrollment
87
Registered
2018-05-29
Start date
2018-06-04
Completion date
2026-12-31
Last updated
2026-08-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Posttraumatic Stress Disorder

Keywords

Prazosin, Nightmares, N-of-1

Brief summary

Post-traumatic stress disorder (PTSD) affects many individuals who experience a traumatic event. There are a variety of treatment options for PTSD, including psychotherapy (talk therapy) options, as well as medications, such as the drug prazosin. Each of the treatment options available is effective at significantly reducing the symptoms of PTSD in some, but not all, individuals with PTSD. However, investigators are not yet able to predict in advance who is likely to respond to which of the available treatments. Neither are the investigators able to explain what changes in the brain after exposure to a traumatic stressors, and why it results in persistent symptoms of PTSD for some people, but not for others. In this study, the investigators are testing two things: First, is testing whether two simple, easy tests of how an individual's blood pressure changes with standing and how an individual's eye reacts to a pulse of light may be able to predict whether that person is likely to respond to the medication prazosin for PTSD. Second, is testing whether those who have been exposed to a traumatic stress show differences in how their body regulates the response to the stress-signal noradrenaline.

Detailed description

In this study, individuals will undergo an assessment that includes taking a history of their previous exposure to traumatic events, an assessment of current mental health symptoms including those associated with PTSD, and an assessment of physiologic measures, such as blood pressure and pupillary responses to light. For individuals who have current symptoms of PTSD and for whom use of the medication prazosin is a reasonable and safe option, a second phase of the study will be offered. In this second phase, how the individual's PTSD symptoms change when taking prazosin will be assessed. In addition, to test whether any changes are related to the prazosin itself or are part of a placebo effect, the individual will be randomly assigned to periods where he or she is taking a pill that looks like prazosin but is actual placebo (a pill with no active ingredient), and periods where he or she is taking a pill that looks the same but this time is actual prazosin. Of note, there is also an additional observational portion of the protocol that is not a direct part of the interventional trial described here, but data from which will be used to help to interpret the data from the interventional trial; because reporting of study results depends on both portiosn, the study completion date estimates/reports will reflect when both the interventional and observational trial components are complete.

Interventions

DRUGPrazosin

This is an antagonist of the alpha1 receptor for noradrenaline. It is FDA approved for the treatment of hypertension, and has also been used for benign prostatic hypertrophy (BPH). Most recently, it has been found to be helpful for symptoms of PTSD in some but not all participants.

DRUGPlacebo

This is a capsule containing an inert substance, in order to provide blinding to participants and study staff of when participants are on active medication and when they are not during the later portions of the trial.

Sponsors

VA Office of Research and Development
Lead SponsorFED

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)

Masking description

During the portion of the study where participants are receiving either placebo or blinded prazosin, the participants, care providers, and outcomes assessors will all be blinded as to whether the participant is at that time receiving prazosin or placebo.

Intervention model description

This study is a modified cross-over study, also called an aggregated N-of-1 study. Each participant who meets criteria for participation in and completes the treatment portion of the study will spend time on open-label prazosin, blinded prazosin, and placebo.

Eligibility

Sex/Gender
ALL
Age
21 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

* Veteran of the U.S. Armed Forces * Current diagnosis of PTSD (as documented in clinical chart and/or per participant report; a rule out diagnosis from a VA provider accompanied by a referral to the VA PTSD Outpatient Clinic (POC) will also be considered sufficient for inclusion) * Woman of childbearing potential must agree to abstain from sexual relations that could result in pregnancy or use an effective method of birth control acceptable to both participant and study clinician during the study. Men are not required to use contraception during the study.

Exclusion criteria

* Psychiatric: * Any known diagnosis of a primary psychotic or major neurocognitive disorder, including schizophrenia, brief psychotic disorder, or Alzheimer's or other dementia, as well as bipolar type I * Severe psychiatric instability or severe situational life crises, including evidence of being actively suicidal or homicidal, or any behavior which poses an immediate danger to participant or others. * Note: Nonsuicidal depression comorbid with PTSD will not be exclusionary. Participants may continue in any concurrent psychotherapy or pharmacotherapy in which they are participating, other than pharmacotherapeutic agents specifically listed above. Participants with active suicidal ideation or with depression severe enough to require psychiatric hospitalization will be excluded. * Medical: * Significant bilateral visual loss (would preclude performing the PLR measurements) * Current pregnancy or lactation * Allergy or previous adverse reaction to prazosin or other alpha-1 antagonist * Acute or unstable chronic medical illness, including unstable angina, recent myocardial infarction (within 6 months), congestive heart failure, preexisting hypotension (systolic \<110) or orthostatic hypotension (systolic drop \> 20mmHg after two minutes standing or any drop accompanied by dizziness); autoimmune disorders; insulin-dependent diabetes * Chronic renal or hepatic failure, acute pancreatitis, Meniere's disease, benign positional vertigo, or narcolepsy * Medication / treatment: * Any use within the 7 days prior to baseline of prazosin, doxazosin, clonidine, guanfacine, trazodone, or nonbenzodiazepine hypnotics, and/or unwillingness to avoid these medications for the duration of the study * Use of avanafil (Stendra), sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra) will be not be permitted during the study dose titration period because of increased risk of hypotension in combination with alpha-1 blockers, but will be allowed at 1/2 the usual starting dose following dose titration * Current use of nitrates, or of alternative medications or supplements with significant vasodilatory properties (e.g., nitrate containing supplements) * Participants may also be excluded at the discretion of PI or study clinicians if they appear to be unsuitable for this research study for a reason not detailed here.

Design outcomes

Primary

MeasureTime frameDescription
Change in total PTSD Checklist for DSM 5 (PCL5) scoreThe PCL5 total score is assessed at baseline, during each stage of the study, and at the endpoint of the study. Thus, measurements will be scheduled to occur at the following time points, relative to the baseline visit: 0, 4, 8, 9-12, 16, and 20 weeksThe PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM 5) is a self-reported rating scale where an individual rates the severity of each symptom of PTSD on a Likert scale. The ratings on individual items are summed to create a total score, which ranges from 0 to 80, with higher scores indicating more symptoms. The relationship between changes in participants' total PCL scores at different time points and prazosin exposure - and whether this relationship is moderated by baseline biomarker values - will be analyzed using a linear mixed effects model.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORRebecca C. Hendrickson, MD PhD

VA Puget Sound Health Care System Seattle Division, Seattle, WA

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Aug 15, 2026