Condition category
Mental and Behavioural Disorders
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration and not expected to be available in the future

Trial website

Contact information



Primary contact

Dr Isobel Heyman


Contact details

Department of Child and Adolescent Psychiatry - PO85
Institute of Psychiatry
De Crespigny Park
United Kingdom
+44 (0)20 3228 5222

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

A randomised double-blind placebo-controlled pilot study of D-cycloserine-augmented exposure therapy in adolescents with obsessive-compulsive disorder


Study hypothesis

The principal research objective is to establish the clinical effectiveness of D-cycloserine- (DCS-) augmented cognitive behavioural therapy (CBT) for children and adolescents with obsessive-compulsive disorder (OCD). Our hypothesis is that the effectiveness of CBT for OCD, and speed of recovery, can be improved by the addition of a small dose of DCS.

Ethics approval

Kings College Hospital Research Ethics Committee (REC) gave approval in December 2008 (ref: 08/H0808/203)

Study design

Single-centre double-blind randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Obsessive-compulsive disorder


The trial will consist of two arms. In the first arm, young people will receive cognitive behaviour therapy with a small dose of D-cycloserine (50 mg) given after sessions 3 to 12. In the second arm, young people will receive cognitive behaviour therapy with a placebo pill given after sessions 3 to 12.

Total duration of treatment in both arms is 14 weeks, and total duration of follow-up in both arms is 12 months, with follow-up evaluations planned to occur at 3 months, 6 months, and 12 months.

Intervention type



Not Applicable

Drug names


Primary outcome measure

Children's Yale Brown Obsessive Compulsive Scale (CYBOCS), a well-validated clinician administered measure of OCD severity. For each arm, this measure will be administered at the beginning of each session, and again at 3 months, 6 months and 12 months post-treatment.

Secondary outcome measures

1. Diagnosis of OCD as determined with:
1.1. The Anxiety Disorders Interview Schedule for DSM-IV (ADIS), the Child Obsessive-Compulsive Inventory (ChOCI), child and parent versions
1.2. The Strengths and Difficulties Questionnaire (SDQ), child and parent versions
1.3. The Beck Depression Inventory for Youth (BDI-Y)
1.4. The Depression Anxiety and Stress Scale (DASS) for parents
1.5. The Family Accommodation Scale (FAS)
2. Additional ‘process’ variables include measures of trait anxiety (RCMAS), threat perception (CARBQ-C/P), subjective anxiety (SUDS ratings), behavioural avoidance tasks (BATs), physiological arousal (heart rate variability) and the Patient Exposure Adherence Scale (PEAS)
3. Behavioural Avoidance Task (BAT). A single task, single-step BAT will be administered. The task will be described to the child using standardised instructions. The BAT is an individually tailored task in which the young person is asked to expose him/herself to a situation that usually causes him/her significant distress or results in compulsive rituals.
4. Subjective units of distress (SUDS). Young people will be asked to rate their subjective distress at various time points during the BAT task, based on an 8-point Likert scale thermometer (0 = none to 8 = extreme).
5. Heart Rate Variability (HRV). HRV is a measure of the beat-to-beat variations in heart rate. It is calculated by analysing a time series of beat-to-beat intervals from a heart rate monitor. HRV is an indicator of autonomic arousal, and there is a known relationship between HRV and emotional arousal. HRV has been shown to be sensitive to the emotion of fear in most people. Therefore HRV will be used as a measure of physiological arousal in relation to the BAT task. HRV will be measured using a Polar heart rate monitor (FT80). A heart rate monitor consists of two elements: a chest strap transmitter and a wrist receiver (a sports watch). The chest strap has electrodes in contact with the skin to monitor electrical voltages in the heart.
6. Cognitive and Avoidant Response Bias Questionnaire - Child and Parent Versions (CARBQ-C/P). Threat perception and coping expectations in response to both generic, non-salient situations as well as to personally salient situations (i.e. situations that the young person perceives to be anxiety provoking) will be measured using the Cognitive and Avoidant Response Bias Questionnaire (CARBQ). It is also of interest to examine parents (mothers) levels of threat perception and coping expectations for their child.

Secondary outcome measures will be completed at 3 months, 6 months and 12 months post-treatment.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) diagnosis of OCD
2. Aged 12 to 18 years
3. Either sex
4. Any ethnicity, religious background or sexual orientation
5. Referred to the National and Specialist OCD Clinic at Maudsley Hospital
6. If on medication, this should be stable for 12 weeks and not be changed during the course of the trial
7. Provision of written informed consent (patient and carer)

Participant type


Age group




Target number of participants

24, with 12 in each arm of the trial

Participant exclusion criteria

1. Current diagnosis of psychosis, current alcohol or substance abuse/dependence
2. English too poor to engage in treatment
3. Severe disabling neurological disorder
4. Medical contraindication to cycloserine, including epilepsy and porphyria
5. A diagnosed global learning disability or pervasive developmental disorder
6. Characteristics interfering with completion of treatment, e.g. life threatening or unstable medical illness
7. Pregnancy
8. Not suitable for CBT (selective mutism, lack of insight or motivation for change)

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Department of Child and Adolescent Psychiatry - PO85
United Kingdom

Sponsor information


Institute of Psychiatry, Kings College London (UK)

Sponsor details

c/o Professor Peter McGuffin
Dean's Office
PO 01
De Crespigny Park
United Kingdom

Sponsor type

Research organisation



Funder type


Funder name

National Institute for Health Research (NIHR) (UK) - Biomedical Research Centre for Mental Health (ref: PAXKAYI)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2013 results in:

Publication citations

  1. Results

    Mataix-Cols D, Turner C, Monzani B, Isomura K, Murphy C, Krebs G, Heyman I, Cognitive-behavioural therapy with post-session D-cycloserine augmentation for paediatric obsessive-compulsive disorder: pilot randomised controlled trial., Br J Psychiatry, 2014, 204, 1, 77-78, doi: 10.1192/bjp.bp.113.126284.

Additional files

Editorial Notes