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Phobic DisordersPhase 3NCT01102803

D-Cycloserine to Enhance Cognitive Behavioral Therapy (CBT) for Acrophobia

A Phase 3 study testing Individual Cognitive Behavioral Therapy (CBT) and D-Cycloserine in people with Phobic Disorders, run by Southern Methodist University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

The purpose of this study is to investigate the utility of post-session administration of D-cycloserine to enhance fear extinction in a sample of people with acrophobia who will be treated with CBT. Read more about this study

Who is it for?
Ages 18 to 65 yearsHealthy volunteers can take part
Conditions the study is for
Phobic Disorders
What is being tested?
Individual Cognitive Behavioral Therapy (CBT) and D-Cycloserine
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
40 participants
Where
1 siteUnited States
Study dates
Apr 2010to Jul 2011
Phase
Phase 3
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 65 years
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • Males or females 18-65 years of age with a psychiatric diagnosis of acrophobia defined by DSM-IV criteria.
  • Willingness and ability to comply with the requirements of the study protocol.

Who cannot join

  • A lifetime history of bipolar disorder, schizophrenia, psychosis, delusional disorders or obsessive-compulsive disorder; an eating disorder in the past 6 months; organic brain syndrome, mental retardation or other cognitive dysfunction that could interfere with capacity to engage in therapy; a history of substance (amphetamines, benzodiazepines, barbiturates, cocaine metabolites, marijuana, narcotics, and sedative hypnotics) abuse or dependence or alcohol abuse or dependence (other than nicotine) in the last 6 months or otherwise unable to commit to refraining from alcohol use during the acute period of study participation.
  • Patients with posttraumatic stress disorder and panic disorder within the past 6 months are excluded. Entry of patients with other mood or anxiety disorders will be permitted in order to increase accrual of a clinically relevant sample. Patients with significant suicidal ideation (MADRS item 10 score > 3) or who have enacted suicidal behaviors within 6 months prior to intake will be excluded from study participation and referred for appropriate clinical intervention.
  • Patients must be off concurrent psychotropic medication (e.g., antidepressants, anxiolytics, beta blockers) for at least 2 weeks prior to initiation of randomized treatment.
  • Significant personality dysfunction likely to interfere with study participation.
  • Serious medical illness or instability for which hospitalization may be likely within the next year.
  • Patients with a current or past history of seizures.
Show all 12Show fewer
  • Pregnant women, lactating women, and women of childbearing potential who are not using medically accepted forms of contraception (e.g., IUD, oral contraceptives, barrier devices, condoms and foam, or implanted progesterone rods stabilized for at least 3 months).
  • Any concurrent psychotherapy initiated within 3 months of baseline, or ongoing psychotherapy of any duration directed specifically toward treatment of acrophobia is excluded. Prohibited psychotherapy includes CBT therapy focusing on exploring specific, dynamic causes of the phobic symptomatology and provides management skills. General supportive therapy initiated > 3 months prior is acceptable.
  • Prior non-response to adequately delivered exposure (i.e., as defined by the patient's report of receiving specific and regular exposure assignments as part of a previous treatment) will exclude participants from the study.
  • Patients with a history of head trauma causing loss of consciousness, seizure or ongoing cognitive impairment.
  • Patients receiving isoniazid.
  • Patients unable to understand study procedures and participate in the informed consent process.

Trial locations and contacts

1 site in 1 country.

United States1 site
  • Southern Methodist University

    Dallas, Texas, 75206

Other trials in United States

About this study

Official title: Evaluation of the Effects of Post-Session Administration of D-cycloserine On Exposure Therapy Outcomes

The purpose of this study is to investigate the utility of post-session administration of D-cycloserine to enhance fear extinction in a sample of people with acrophobia who will be treated with CBT.

Being tested
Individual Cognitive Behavioral Therapy (CBT), D-Cycloserine, Placebo
Keywords
Phobias, Anxiety Disorders, D-Cycloserine, Phobic Disorders, Mental Disorders, Heights, Acrophobia
Medical subject headings
Phobic Disorders, Anxiety Disorders, Mental Disorders, Acrophobia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Individual Cognitive Behavioral Therapy (CBT)Behavioural

    Also called CBT, DCS

    The aim of CBT is to help participants become more comfortable with heights situations. Participants will receive 2 sessions over two weeks of individual CBT.

  • D-CycloserineDrug

    D-Cycloserine

  • PlaceboDrug

    Sugar Pill

Study groups in NCT01102803
Study groupRoleWhat they receive
Sugar PillPlacebo comparatorParticipants will receive placebo augmented cognitive behavioral therapy
Receives: Behavioral: Individual Cognitive Behavioral Therapy (CBT); Drug: Placebo
D-CycloserineExperimentalParticipants will receive D-Cycloserine augmented cognitive behavioral therapy
Receives: Behavioral: Individual Cognitive Behavioral Therapy (CBT); Drug: D-Cycloserine

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Acrophobia Questionnaire With Avoidance (AAVQ)

    Self-report measure that assesses fear and avoidance of a variety of heights situations. This questionnaire (Cohen, 1977) describes 20 situations and assesses levels of avoidance (0-3) and anxiety (0-6). These scales widely used measure of acrophobia with adequate retest reliability (r = .82-.86) and validity (Baker et al., 1973). Higher scores indicate higher levels of avoidance/anxiety (i.e., worse outcome). All subscales are summed for a total score. AAVQ will be assessed at each visit throughout the 2 month protocol. The minimum score is 0, the maximum is 90.

    Measured: 2 months

Secondary outcomes (3)
  1. Attitudes Towards Heights Questionnaire (ATHQ)

    Self-report measures that assesses thoughts and feelings towards heights situations. This questionnaire (Abelson and Curtis, 1989) includes six heights situations and assesses attitudes toward these situations using a 0-10 scale. Higher scores indicate a worse outcome and total scores are summed over subscales. Will be assessed at each visit throughout the 2 month protocol. The minimum score is a 0; the maximum is a 60.

    Measured: 2 months

  2. Clinical Global Improvement Scale (CGI)

    Clinician-rated measure of improvement in acrophobia symptoms and severity. Will be assessed at each visit throughout the 2 month protocol. The CGI-S and CGI-I are widely used measures of global psychopathology severity and improvement initially developed for the study of psychotropic drugs (Guy, 1970). In order to obtain CGI ratings, the therapists (blind to study condition) interviewed the participant and used the SCID (including the specific phobia module) as well as the additional measures of acrophobia symptoms (BAT, AAQ, AAVQ, and ATHQ). In the current study, response was defined as either "very much improved" or "much improved" on CGI-I (score ≤ 2). Remission was defined as either "normal" or "minimally ill" on CGI-S (score ≤ 2). The minimum rating is a 1 and the highest is a 7. Lower scores indicate a better outcome.

    Measured: 2 months

  3. Behavioral Avoidance Test (BAT)

    During the initial screen, at post-treatment, and at follow-up, participants underwent a behavioral avoidance test in the virtual reality height environment. Participants reported on a 0-100 scale (100 being the most intense fear) their SUDS for floors 1, 2, 3, 4, 9, 19 of the virtual glass elevator and balconies. This test has been used successfully as a measure of treatment gains in previous studies of acrophobia research (Ressler et al., 2004). For the outcome analyses, we included the level of fear reported at the highest floor of the virtual elevator environment (19th floor). Higher scores indicate a worse outcome.

    Measured: 2 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted13 Apr 2010 (estimated)
  2. Study startApr 2010
  3. Primary completionJul 2011
  4. Study completionJul 2011

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Triple blind
Who is masked
Participant, Investigator, Outcomes assessor
Enrolment
40 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT01102803
Sponsor's protocol ID
KS09-81
Status last verified
Dec 2012
First submitted
9 Apr 2010
Last updated
21 Feb 2013
Data monitoring committee
No

Publications

  • Smits JA, Rosenfield D, Otto MW, Powers MB, Hofmann SG, Telch MJ, Pollack MH, Tart CD. D-cycloserine enhancement of fear extinction is specific to successful exposure sessions: evidence from the treatment of height phobia. Biol Psychiatry. 2013 Jun 1;73(11):1054-8. doi: 10.1016/j.biopsych.2012.12.009. Epub 2013 Jan 16.

    PubMed 23332511
  • Tart CD, Handelsman PR, Deboer LB, Rosenfield D, Pollack MH, Hofmann SG, Powers MB, Otto MW, Smits JA. Augmentation of exposure therapy with post-session administration of D-cycloserine. J Psychiatr Res. 2013 Feb;47(2):168-74. doi: 10.1016/j.jpsychires.2012.09.024. Epub 2012 Oct 23.

    PubMed 23098672

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Individual Cognitive Behavioral Therapy (CBT) and D-Cycloserine in people with Phobic Disorders, run by Southern Methodist University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 21 Feb 2013. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 21 Feb 2013). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Acrophobia Questionnaire With Avoidance (AAVQ) (time frame: 2 months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT01102803, which also lists 2 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Feb 2013.

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