Exposure, D-cycloserine Enhancement, and Functional Magnetic Resonance Imaging (fMRI) in Snake Phobics

March 13, 2024 updated by: Hartford Hospital
The aim of the present study is to determine whether people receiving d-cycloserine and exposure therapy show different brain reactions to symptom provocation compared to people receiving placebo and exposure therapy.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

D-cycloserine (DCS) is a partial N-methyl-D-aspartate (NMDA) receptor agonist that may improve or accelerate extinction learning. We will randomly assign people with snake phobia to receive DCS or placebo, and then provide all participants with exposure therapy. We will examine whether people receiving DCS and vs. placebo show different brain reactions to symptom provocation before and after exposure therapy.

Study Type

Interventional

Enrollment (Actual)

20

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Connecticut
      • Hartford, Connecticut, United States, 06106
        • Institute of Living/Hartford Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Primary diagnosis of specific phobia (snakes)

Exclusion Criteria:

  • History of psychosis, obsessive-compulsive disorder, or mania
  • Recent substance abuse or suicidality
  • Previous receipt of study treatments

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: D-cycloserine plus exposure therapy
Single session (up to 3 hr) of in vivo exposure therapy plus 50 mg oral d-cycloserine administered 1 hr prior to exposure therapy session
Drug: D-cycloserine
50 mg d-cycloserine, oral, 1 dose
Behavioral: Exposure therapy
Single session graded in vivo exposure therapy, 60-180 minutes
Placebo Comparator: Placebo plus exposure therapy
Single session (up to 3 hr) of in vivo exposure therapy plus oral placebo capsule administered 1 hr prior to exposure therapy session
Behavioral: Exposure therapy
Single session graded in vivo exposure therapy, 60-180 minutes
Drug: Placebo
Single capsule of oral placebo, administered once 1 hr prior to exposure therapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Snake Questionnaire (SNAQ)
Time Frame: 2 weeks

30-item self-report scale of severity of snake fear and avoidance

Range: 0-30; higher values indicate greater fear severity
2 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinician's Global Impression (CGI)-Severity
Time Frame: 2 weeks

Clinician rating of global illness severity (at pre- and post-treatment)

CGI-Severity range 1-7; higher scores indicate greater illness severity.
2 weeks
Clinician's Global Impression (CGI)-Improvement
Time Frame: 2 weeks

Clinician rating of global illness severity (at post-treatment)

CGI-Improvement range 1-7; higher scores indicate poorer improvement; classified as responder if score = 1 or 2, nonresponder if score > 2
2 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Hartford Hospital

Investigators

  • Principal Investigator: David Tolin, PhD, Hartford Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

July 1, 2010

Primary Completion (Actual)

December 1, 2011

Study Completion (Actual)

December 1, 2011

Study Registration Dates

First Submitted

October 6, 2011

First Submitted That Met QC Criteria

October 11, 2011

First Posted (Estimated)

October 12, 2011

Study Record Updates

Last Update Posted (Actual)

March 15, 2024

Last Update Submitted That Met QC Criteria

March 13, 2024

Last Verified

March 1, 2024

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • NAVE003220HU

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified data will be made available upon request

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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