NCT06852469 · VA Office of Research and Development
Computational Assessment of GABA Receptor Modulation in PTSD
What this study is about
A substantial majority of Veterans with posttraumatic stress disorder (PTSD) continue to suffer even with the best current medications. Progress in developing more effective medications is hampered by the substantial variability within Veterans with PTSD, meaning the most effective medication likely varies from individual to individual.
View original scientific description
A substantial majority of Veterans with posttraumatic stress disorder (PTSD) continue to suffer even with the best current medications. Progress in developing more effective medications is hampered by the substantial variability within Veterans with PTSD, meaning the most effective medication likely varies from individual to individual. New scientific tools to help identify distinct subgroups of Veterans with PTSD who are likely to respond to specific medications could help improve treatment in this population. Research has indicated that a specific subgroup of Veterans with PTSD with a high level of anxious arousal may benefit from medications which boost signaling of the neurotransmitter gamma-aminobutyric acid (GABA). This project aims to validate a clinical test to identify these individuals using new computational and neuroimaging methods combined with the medication lorazepam, a positive GABA modulator. The ultimate goal is to use these methods in future clinical trials of new medications to target the best treatments to individual Veterans with PTSD.
Interventions
DRUG
Lorazepam 1 mg tablet
Lorazepam is an oral medication which is FDA approved to treat anxiety.
DRUG
Placebo tablet
Placebo will match the study drug in mode of administration, color, size, and taste.
Primary outcome measures
Dynamic inhibition during sensorimotor control
Time frame: 1.5 hours after dosing
A dynamic inhibition parameter will be computed for each participant and session using a proportional-derivative (PD) model of sensorimotor control performance on the rapid assessment of motor processing (RAMP) task.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- 18-65 years of age, inclusive;
- Participants must be willing to abstain from alcohol 24 hours prior to and 24 hours after the testing session;
- Participants must be able to participate and willing to give written informed consent and to comply with the study restrictions; Additional Inclusion Criteria for PTSD Group: (a) Current diagnosis of PTSD based on CAPS-5.
Exclusion criteria
- Has uncontrolled, clinically significant neurologic (including seizure disorders), cardiovascular, pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, endocrine disease, or psychiatric disorder, or other abnormality, which may impact the ability of the subject to participate or potentially confound the study results;
- Pregnancy (assessed by urine test at time of screening and prior to administration of study medication) or lactation;
- Lifetime history of a chronic psychotic disorder or bipolar disorder type I as assessed by MINI;
- Current moderate or severe substance use disorder as assessed by MINI;
- Positive urine toxicology (drugs of abuse as determined by a positive urine test) at screening and before drug administration. Subjects who screen positive for THC will be given an opportunity to be included in the event of a negative urine test 2 weeks later. THC is not infrequently used for medicinal purposes and, in California, is legal for recreational use. Subjects who are positive for THC will therefore not be excluded, but will be retested to ensure that THC is unlikely to be influencing results;
- Self-report or observable signs of drug or alcohol intoxication or withdrawal;
- Current benzodiazepine or opioid use; other psychotropic medications are allowed as long as they are at a stable dose for at least 2 weeks and do not exhibit an unsafe interaction with the study medication;
- Current or recent use of any medication deemed by the study physician (Dr. Howlett) to exhibit an unsafe interaction with lorazepam;
- Past intolerance (including allergic) to lorazepam or another benzodiazepine;
- Active suicidal ideation or otherwise considered at high suicidal risk by trained study staff using the C-SSRS;
- History of a traumatic brain injury (TBI) resulting in loss of consciousness for more than 30 minutes;
- Volunteers who do not have sufficient command of the English language, or who have any other impairment that would prevent them from reading and understanding the informed consent form(s) and completing the study procedures including clinical testing;
- Any other reason why, per study physician, the subject should not participate in this study, including concomitant disease or condition that could interfere with, or for which the study drug might interfere with, the conduct of the study, or that would, in the opinion of the study physician, pose an unacceptable risk to the subject in this study. Additional Exclusion Criteria for HC Group: (a) Axis I disorder as assessed by MINI. Additional Exclusion Criteria for fMRI Participants:
- Contraindication to magnetic resonance imaging.
- Not right-handed as assessed by Edinburgh Handedness Inventory.
Where
- San Diego, California
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 16, 2026 · Source of record for eligibility and locations