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 endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
A randomised double blind placebo controlled clinical trial of the efficacy of an Australian naltrexone implant compared to oral naltrexone for the long-term management of heroin-dependent persons
Scientific title
A randomised double blind placebo controlled clinical trial of naltrexone implants for the treatment of heroin addiction
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Heroin dependence 1279 0
Condition category
Condition code
Mental Health 1366 1366 0 0

Study type
Description of intervention(s) / exposure
A randomised, double placebo, double blind trial comparing the O’Neil long acting naltrexone subcutaneous implant (3.6g release rate 0.4% / day) plus placebo capsule with placebo implant plus capsules containing 50mg naltrexone hydrochloride. Participants will receive the intervention and data will be collected for a total of 6 months.
Intervention code [1] 1203 0
Treatment: Drugs
Comparator / control treatment
Double Placebo
Control group

Primary outcome [1] 1867 0
Proportion with blood naltrexone concentrations above therapeutic levels (2 ng/ml)
Timepoint [1] 1867 0
Measured at 1, 2, 3, 4, 5, & 6 months
Primary outcome [2] 1868 0
Number of accidental opiate overdoses (hospital admissions or ED presentations) to 6 months
Timepoint [2] 1868 0
baseline to 6 months
Secondary outcome [1] 3284 0
Opiate related morbidity (hospital admissions) and mortality to 6 months
Timepoint [1] 3284 0
baseline to 6 months
Secondary outcome [2] 3285 0
Craving for heroin questionnaire (Tiffany).
Timepoint [2] 3285 0
Measured at 0, 1, 2, 3, 4, 5, & 6 months.
Secondary outcome [3] 3286 0
Proportion returning to dependent heroin/opiate use (DSM IV criteria).
Timepoint [3] 3286 0
At 6 months.
Secondary outcome [4] 3287 0
Frequency of other drug use.
Timepoint [4] 3287 0
At 0, 1, 2, 3, 4, 5, & 6 months.
Secondary outcome [5] 3288 0
Other drug related accidental overdose, other morbidity (hospital admission or ED presentation) or mortality to 6 months
Timepoint [5] 3288 0
baseline to 6 months
Secondary outcome [6] 3289 0
Opiate Treatment Index scores.
Timepoint [6] 3289 0
At 0, 1, 2, 3, 4, 5, & 6 months.

Key inclusion criteria
Heroin dependence (DSM-IV criteria which covers the previous 12 months)Resident in the Perth (Western Australia) metropolitan area or regional areas with approved study support services Willing and able to provide written informed consentWilling to be randomised to either arm of the studySatisfactory completion of screening questionnaire.
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
High risk of overdose (3+ overdoses in previous month)Non compliant with oral naltrexone (4 + times in last 3 months) or prior implantPregnancyContra indications or prior adverse reactions for study medications/procedures.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Numbered containers
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation was based on computer generated random numbers, using a variable block size with a unified allocation ratio
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Phase 2
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] 1501 0
Government body
Name [1] 1501 0
National Health & Medical Research Council
Country [1] 1501 0
Primary sponsor type
University of Western Australia
35 Stirling Highway
Secondary sponsor category [1] 1318 0
Name [1] 1318 0
Address [1] 1318 0
Country [1] 1318 0

Ethics approval
Ethics application status
Ethics committee name [1] 2923 0
University of Western Australia HREC
Ethics committee address [1] 2923 0
35 Stirling Highway,
Ethics committee country [1] 2923 0
Date submitted for ethics approval [1] 2923 0
Approval date [1] 2923 0
Ethics approval number [1] 2923 0

Brief summary
GoMedical Industries has developed a formulation of sustained release naltrexone, suitable for subcutaneous depot administration. Currently, implants are inserted by minor surgery under local anaesthetic in high risk patients under the Therapeutic Goods Administration (TGA) Special Access Category A scheme (SAS) through the Australian Medical Procedures Research Foundation (AMPRF), Western Australia. Although there is a preliminary basis for believing that this naltrexone implant treatment may offer significant benefits over oral and other naltrexone depot preparations thus far reported for managing the heroin dependent patient, this needs to be verified through a clinical trial. Hence, the main objective of this study is to provide rigorous clinical data using a double blind, double placebo controlled study, on the effectiveness of this naltrexone implant compared to oral naltrexone in the management of heroin dependent persons by primarily monitoring: maintenance of blood naltrexone and 6-b-naltrexol concentrations above therapeutic levels; prevention of accidental opiate overdose; reduced opiate use; reduced opiate related morbidity and mortality; reduced craving for heroin and other health related outcomes.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 35302 0
Address 35302 0
Country 35302 0
Phone 35302 0
Fax 35302 0
Email 35302 0
Contact person for public queries
Name 10392 0
Dr Robert Tait
Address 10392 0
School of Psychiatry & Clinical Neurosciences,
University of Western Australia,
QE II Medical Centre, MPC 521,
Nedlands, Perth SA
Country 10392 0
Phone 10392 0
+61 8 9346 2281
Fax 10392 0
+61 8 9346 3828
Email 10392 0
Contact person for scientific queries
Name 1320 0
Professor Gary Hulse
Address 1320 0
School of Psychiatry & Clinical Neurosciences
University of Western Australia
QE II Medical Centre MPC 521
Nedlands Perth
Country 1320 0
Phone 1320 0
+61 8 9346 2280
Fax 1320 0
+61 8 9346 3828
Email 1320 0

No information has been provided regarding IPD availability

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
Dimensions AIImproving Clinical Outcomes in Treating Heroin Dependence: Randomized, Controlled Trial of Oral or Implant Naltrexone2009
N.B. These documents automatically identified may not have been verified by the study sponsor.