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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Date results information initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Using d-cycloserine to increase the effects of exposure for children's general fears
Scientific title
d-cycloserine vs placebo combined with in-vivo exposure in the reduction of specific fears among children with broad-based anxiety disorders
Secondary ID [1] 262495 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Child anxiety 268182 0
Condition category
Condition code
Mental Health 268311 268311 0 0

Study type
Description of intervention(s) / exposure
d-cycloserine - 50 mg oral capsules, taken on 5 weekly occasions, approximately 60 minutes prior to each initial exposure
in-vivo exposure - 5 weekly sessions of approximately 30 minutes with a therapist. Exposure is conducted hierarchically during sessions to main identified fear.
Intervention code [1] 266848 0
Intervention code [2] 266849 0
Treatment: Drugs
Comparator / control treatment
placebo - oral microcellulose capsule taken as above - ie 5 indiviaul doses at weekly sessions approximately 60 minutes prior to initial exposure.
All participants (including those on placebo) receive identical in-vivo exposure.
Control group

Primary outcome [1] 269065 0
Anxiety and avoidance of key fear assessed via behavioural avoidance test
Timepoint [1] 269065 0
Pre, Weekly for 5 weeks, post
Secondary outcome [1] 276892 0
General anxiousness assessed via Spence Children's Anxiety Scale
Timepoint [1] 276892 0
Pre, Weekly for 5 weeks, post

Key inclusion criteria
DSM diagnosis of anxiety disorder
Availability of specific fear
Minimum age
7 Years
Maximum age
14 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Psychotic experiences
Suicidal risk
Kidney disease
Liver disease
Prior allergic reaction to antibiotics

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants are diagnosed and assessed by clinician who is independent of study. All those who meet criteria are invited to participate. Group allocation (active vs placebo) done by random number generator. Allocation and blind is held by hosptial pharmacist who is not involved in study in any other way. Therapist, interviewers, and participants are all blind to condition.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random number generator.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 267325 0
Government body
Name [1] 267325 0
Australian Research Council
Address [1] 267325 0
Level 2, 11 Lancaster Place
Majura Park ACT 2609
Country [1] 267325 0
Primary sponsor type
Macquarie University
Balaclava Rd
North Ryde.
NSW. 2109
Secondary sponsor category [1] 266391 0
Name [1] 266391 0
Address [1] 266391 0
Country [1] 266391 0

Ethics approval
Ethics application status
Ethics committee name [1] 269311 0
Macquarie University Human Research Ethics Committee
Ethics committee address [1] 269311 0
Balaclava Rd.
North Ryde.
NSW. 2109.
Ethics committee country [1] 269311 0
Date submitted for ethics approval [1] 269311 0
Approval date [1] 269311 0
Ethics approval number [1] 269311 0

Brief summary
The trial aims to test the efficacy of d-cycloserine (DCS) to augment the effects of in-vivo exposure for children's fears. It is hypothesised that anxious children who receive in-vivo exposure for a specific fear will show reductions in that fear and that use of DCS will increase the rate and extent of fear reduction. Children will receive 5 individual sessions of graduated exposure for a key, specific fear and will take either DCS (50 mg) or placebo approx 60 minutes before exposure.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 32803 0
Prof Ronald Rapee
Address 32803 0
Department of Psychology,
Macquarie University
NSW 2109 Australia
Country 32803 0
Phone 32803 0
+61 2 98508032
Fax 32803 0
Email 32803 0
Contact person for public queries
Name 16050 0
Prof Prof Ronald Rapee
Address 16050 0
Department of Psychology,
Macquarie University,
Sydney. NSW. 2109.
Country 16050 0
Phone 16050 0
61 2 98508032
Fax 16050 0
61 2 98508062
Email 16050 0
Contact person for scientific queries
Name 6978 0
Prof Prof Ronald Rapee
Address 6978 0
Department of Psychology,
Macquarie University,
Sydney. NSW. 2109
Country 6978 0
Phone 6978 0
61 2 98508032
Fax 6978 0
61 2 98508062
Email 6978 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
This trial finished several years ago and we do not have ethics approval to share the data!
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary
Use of the partial NMDA receptor agonist d-Cycloserine (DCS) to increase extinction to feared cues among anxious adults has shown mixed, although overall positive effects. Few studies have extended this effect to youth and none have addressed young people with broad-based anxiety such as separation anxiety, social anxiety, or generalised anxiety. In the current trial 51 children and adolescents with diagnosed anxiety disorders, aged 7-14 years received four sessions of graduated, experimenter-led, in vivo exposure to a hierarchy of feared cues relevant to their primary fear. They were randomly allocated to receive either 50 mg of DCS or a matched placebo capsule in a fully double-blind design. Both groups showed large reductions across sessions in their primary fear according to both parent and child report, but there were no significant differences between conditions at any session. The results are consistent with most studies to date of DCS-augmented exposure in young people.