Substance P Antagonist in the Treatment of Posttraumatic Stress Disorder

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00383786
Recruitment Status : Completed
First Posted : October 4, 2006
Results First Posted : January 31, 2014
Last Update Posted : February 13, 2018
National Institute of Mental Health (NIMH)
Information provided by (Responsible Party):
Sanjay Johan Mathew, Baylor College of Medicine

Brief Summary:

This study, conducted at the NIH and the Mount Sinai School of Medicine, will examine the effectiveness of a substance P or NK1 antagonist study drug known as GR205171 in treating the symptoms of posttraumatic stress disorder (PTSD).

People between 18 and 65 years of age who have been diagnosed with PTSD may be eligible for this study. Participants undergo the following tests and procedures:

Treatment: Patients are tapered off current ineffective medications over 1 to 2 weeks. All participants receive placebo (sugar pill) at the start of the study. At some point within the first 3 weeks of the study, they are then randomly assigned either to take GR205171 or to continue with placebo for the remainder of the 10-week treatment period.

Clinic visits: Patients come to the clinic once a week during treatment. The following procedures are done at various visits.

  • Interviews, self report questionnaires and psychiatric rating scales at every visit.
  • Physical examination, blood and urine tests. Blood is drawn up to 10 times during the study.

Follow-up visits continue for up to 3 months after the end of the study, during which patients are offered standard clinical treatment.

Condition or disease Intervention/treatment Phase
PTSD Drug: NK1 Antagoist (GR205171) Procedure: Psychophysiology (Trauma Script) Procedure: Psychophysiology (Verbal Threat) Procedure: Psychophysiology (Fear Conditioning) Procedure: Psychophysiology (Affective Modulation) Procedure: Psychophysiology (Heart rate variability) Procedure: Lumbar Puncture Procedure: 24-hour plasma sampling Procedure: MRI Phase 2

Detailed Description:

Posttraumatic Stress Disorder (PTSD) is a common chronic anxiety disorder that is often debilitating and follows exposure to an overwhelming traumatic event. The burden of PTSD on individuals and society is significant. The majority of PTSD sufferers also meet the diagnostic criteria for several other psychiatric disorders and many attempt suicide. Despite the devastating impact of PTSD on the lives of millions worldwide, little is known about the etiology or pathophysiology of this disorder. Although disruptions in the hypothalamic-pituitary adrenal (HPA) Axis, noradrenergic, serotonergic systems have been proposed as neurobiological substrates in the development of PTSD, the exact underpinnings of the neurobiology of PTSD remain to be fully elucidated.

PTSD is responsive to treatment with selective serotonin reuptake inhibitors, but response rates rarely exceed 60%, and even fewer patients (20%-30%) experience improvement that could be characterized as remission. Thus, there is a clear need to develop novel and improved therapeutics for PTSD. A growing body of preclinical evidence suggests that activation of the Substance P (SP) and its receptor NK1 is anxiogenic and that NK1 antagonists, upon chronic administration, exert significant dampening (albeit complex) effects on the SP-NP system. Furthermore, several stress paradigms are believed to exert many of their deleterious effects on hippocampal structures via enhancement of SP-NK1 system. Overall, excess activity of the SP-NK1 system stands as a prime candidate for involvement in the pathophysiology of anxiety disorders such as PTSD.

In this study, we propose to investigate the potential antianxiety efficacy of the highly specific NK1 antagonist GR205171 in PTSD. Furthermore, we propose to, in a preliminary fashion, longitudinally investigate whether neuroendocrine surrogate markers are predictive of treatment response.

This is an 8-week double-blind placebo-controlled study that will examine the efficacy and safety of an NK1 antagonist in patients with PTSD.

Patients, ages 18 to 65 years with a diagnosis of PTSD, will in this pilot study be randomized to double-blind treatment to receive either the NK1 antagonist, GR205171 (5 mg/day) or placebo for a period of 8 weeks.

Approximately 52 patients will enter the study to obtain 40 subjects who complete the 8 weeks of acute NK1 antagonist treatment.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 47 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
Official Title: Evaluation of the Efficacy of the NK1 Antagonist GR205171 in Posttraumatic Stress Disorder
Study Start Date : September 2006
Actual Primary Completion Date : June 2009
Actual Study Completion Date : June 2009

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: GR205171
selective neurokinin-1 receptor antagonist, fixed 5 mg dose every day, for 8 weeks.
Drug: NK1 Antagoist (GR205171)
Procedure: Psychophysiology (Trauma Script)
Procedure: Psychophysiology (Verbal Threat)
Procedure: Psychophysiology (Fear Conditioning)
Procedure: Psychophysiology (Affective Modulation)
Procedure: Psychophysiology (Heart rate variability)
Procedure: Lumbar Puncture
Procedure: 24-hour plasma sampling
Procedure: MRI
Placebo Comparator: placebo
sugar pill
Procedure: Psychophysiology (Trauma Script)
Procedure: Psychophysiology (Verbal Threat)
Procedure: Psychophysiology (Fear Conditioning)
Procedure: Psychophysiology (Affective Modulation)
Procedure: Psychophysiology (Heart rate variability)
Procedure: Lumbar Puncture
Procedure: 24-hour plasma sampling
Procedure: MRI

Primary Outcome Measures :
  1. Changes in CAPS Scores. [ Time Frame: Baseline, 8 weeks ]
    The Clinician-Administered PTSD Scale (CAPS) is the gold standard in PTSD assessment. The CAPS is a 30-item structured interview that corresponds to the DSM-IV criteria for PTSD. This is a 17-item core symptom scale, measuring both frequency and intensity of symptoms, with the most frequently used scoring rule is to count a symptom as present if it has a frequency of 1 or more and an intensity of 2 or more. A PTSD diagnosis is made if there is at least 1 "B" symptom, 3 "C" symptoms, and 2 "D" symptoms as well as meeting the other diagnostic criteria. Scores range from 0-136 0 (best possible outcome) to 136 (worst possible outcome). The relevant time-points for reporting change were at baseline and 8 weeks.

Secondary Outcome Measures :
  1. Able to Identify Biological Markers That Predict Response to Treatment. [ Time Frame: 10 weeks ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Subjects may be included in the study only if they meet all of the following criteria:

  1. Male or female subjects, 18 to 65 years.
  2. Female subjects of childbearing potential must be using a medically accepted means of contraception.
  3. Each subject must have a level of understanding sufficient to agree to all required tests and examinations and sign an informed consent document.
  4. A negative urine toxicology.
  5. Subjects must fulfill the criteria for PTSD as defined in DSM-IV (309.81), which should be the primary diagnosis. Diagnoses are based on clinical assessment and confirmed by structured diagnostic interview SCID-P.
  6. Duration of illness of PTSD for at least 3 months.
  7. Subjects must have an initial score at Visit 1 and Visit 2 of at least 50 on the CAPS for PTSD Studies.
  8. Subjects must not have a decrease in the total score of CAPS of greater than 25% during washout (between Visits 1 and 2).


Subjects will be excluded from the study for any of the following reasons:

  1. Presence of psychotic features.
  2. Participation in a clinical trial of another investigational drug within 1 month (30 days) prior to study entry (Visit 1).
  3. Female subjects who are either pregnant or nursing.
  4. Serious, unstable illnesses including hepatic, renal, gastroenterologic, respiratory, cardiovascular (including ischemic heart disease), endocrinologic, neurologic, immunologic, or hematologic disease.
  5. Subjects with uncorrected hypothyroidism or hyperthyroidism.
  6. Previous treatment with NK1 receptor antagonist.
  7. DSM-IV substance abuse or dependence within the past 90 days.
  8. Treatment with an injectable depot neuroleptic within less than one dosing interval between depot neuroleptic injections prior to Visit 2.
  9. Treatment with a reversible MAOI, guanethidine, or guanadrel within 1 week or with fluoxetine within 6 weeks prior to Visit 2.
  10. Treatment with any other concomitant medication with primarily CNS activity.
  11. Treatment with clozapine or ECT within 12 weeks prior to Visit 2.
  12. Current diagnosis of schizophrenia or other psychotic disorder, bipolar disorder, other Axis I disorder (except for major depressive disorder, dysthymia and other anxiety disorders that followed exposure to the trauma) as defined in the DSM-IV.
  13. Patients who are currently at high risk for homicide or suicide, a score greater than 4 on item 10 of the MADRS.
  14. Current or planned litigation regarding the traumatic event.

Patients will not be allowed to receive structured psychotherapy during the trial.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00383786

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
United States, New York
Mt. Sinai Medical Center
New York, New York, United States, 10029-0574
Sponsors and Collaborators
Baylor College of Medicine
National Institute of Mental Health (NIMH)
Principal Investigator: Dennis S Charney, MD Icahn School of Medicine at Mount Sinai

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Sanjay Johan Mathew, MD, Baylor College of Medicine Identifier: NCT00383786     History of Changes
Obsolete Identifiers: NCT00211861
Other Study ID Numbers: 060253
First Posted: October 4, 2006    Key Record Dates
Results First Posted: January 31, 2014
Last Update Posted: February 13, 2018
Last Verified: January 2018

Keywords provided by Sanjay Johan Mathew, Baylor College of Medicine:
Substance P
Treatment Study
Post Traumatic Stress Disorder

Additional relevant MeSH terms:
Stress Disorders, Traumatic
Stress Disorders, Post-Traumatic
Trauma and Stressor Related Disorders
Mental Disorders
Substance P
Neurokinin A
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Autonomic Agents
Peripheral Nervous System Agents
Gastrointestinal Agents
Neurokinin-1 Receptor Antagonists