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Trial registered on ANZCTR


Registration number
ACTRN12613000324718
Ethics application status
Approved
Date submitted
11/03/2013
Date registered
22/03/2013
Date last updated
7/11/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
CYP2D6 and the pharmacokinetics of ibogaine
Scientific title
The role of CYP2D6 in the pharmacokinetics of ibogaine in healthy volunteers
Secondary ID [1] 282110 0
None
Universal Trial Number (UTN)
Trial acronym
N/A
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Opioid dependence 288605 0
Condition category
Condition code
Mental Health 288937 288937 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
- Cohort B will consist of volunteers who receive once daily oral doses of paroxetine capsules (Days 2 to 3- paroxetine 10mg and Days 4 to 15- paroxetine 20mg) to induce a CYP2D6 poor metabolizer phenotype.
- Subjects will recieve a single oral dose of ibogaine 20mg on Day 8. Ibogaine will be given open label.
- All subjects will also receive a single oral dose of dextromethorphan 30mg on Days 1 and 7 to determine their in vivo CYP2D6 phenotype.
- All days mentioned in dosing are inclusive of the days listed above.
Intervention code [1] 286711 0
Treatment: Drugs
Comparator / control treatment
- Cohort A will consist of volunteers who receive once daily oral doses of ‘paroxetine-placebo capsules’ from Days 2 to 15.
- Subjects will recieve a single open-label oral dose of ibogaine 20mg on Day 8.
- All subjects will also receive a single oral dose of dextromethorphan 30mg on Days 1 and 7 to determine their in vivo CYP2D6 phenotype.
- All days mentioned in dosing are inclusive of the days listed above.
- Placebo capsules will be identical in appearance to those of active capsules, however will not contain paroxetine.
Control group
Placebo

Outcomes
Primary outcome [1] 289063 0
Plasma pharmacokinetics of ibogaine and its active metabolite
Timepoint [1] 289063 0
predose, 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, 72, 96, 120, 144 and 168h
Secondary outcome [1] 301663 0
Safety
Timepoint [1] 301663 0
- Safety laboratory tests: CBC, electrolytes, dipstick urine at screening and study end.
- vital signs (blood pressure, heart rate) (Day 1: 0, 2, 4h; Day 8: 0, 2, 4, 12h, 24, 48, 72, 96, 120, 144, 168h
Secondary outcome [2] 301874 0
Tolerability
Timepoint [2] 301874 0
Reported adverse events throughout study.
100mm visual analogue scales measuring “sleepy”, “energetic”, “nausea”, “anxious”, “calm” at Day 1: 0, 2, 4h; Day 8: 0, 2, 4, 12, 24, 48, 72, 96, 120, 144 and 168h
Secondary outcome [3] 301875 0
Pharmacodynamics
Timepoint [3] 301875 0
- Psychomotor performance using tests of memory and attention, including simple and choice reaction time. (Day 1: 0, 2, 4h; Day 8: 0, 2, 4, 12h; 24h (Day 9); 168h (Day 15)
- Central (tympanic) temperature (Day 1: 0, 2, 4h; Day 8: 0, 2, 4, 12h; 24h (Day 9); 168h (Day 15)
- Pupillometry to assess pupil diameter, average speed of constriction and dilation to a light flash (Day 1: 0, 2, 4h; Day 8: 0, 1, 2, 3, 4, 6, 12h; 24h (Day 9); 168h (Day 15)
- Computerised tests of memory and attention. These tests assess a range of functions, including memory, reaction time, and measures of attention, Days 1, 7, 8, 9, 15 at approximately 10AM


Eligibility
Key inclusion criteria
Healthy volunteers, drug free, good general health, normal screening lab tests and ECG
Minimum age
20 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Significant medical history, drug use

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Randomization will be based on a computer-generated random code. All study staff will be blinded to treatment allocation. Allocation concealment will be managed useing numbered containers. Subjects will be allocated the next available subject number.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer-generated random code
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 1
Type of endpoint/s
Pharmacokinetics / pharmacodynamics
Statistical methods / analysis
Comparisons of ibogaine PK data between placebo and paroxetine cohorts will be made using independent t-tests or Mann-Whitney test, as appropriate. Population PK and multivariate linear regression techniques will be used to explore the relationship(s) between PK parameters and pharmacodynamic parameters.

Pharmacodynamic variables will be summarised and graphed by Cohort, using means or medians with standard deviations or inter-quartile ranges as appropriate.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 4907 0
New Zealand
State/province [1] 4907 0

Funding & Sponsors
Funding source category [1] 286877 0
University
Name [1] 286877 0
University of Otago
Country [1] 286877 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
PO Box 913
Dunedin 9054, NZ
Country
New Zealand
Secondary sponsor category [1] 285668 0
Commercial sector/Industry
Name [1] 285668 0
Phytostan Enterprises, Inc.
Address [1] 285668 0
925 De Maisonneuve Blvd. West, Suite 110
Montreal, Quebec H3A OA5
Country [1] 285668 0
Canada

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 288940 0
Southern Health and Disability Ethics Committee
Ethics committee address [1] 288940 0
1 The Terrace
PO Box 5013
Wellington 6145
Ethics committee country [1] 288940 0
New Zealand
Date submitted for ethics approval [1] 288940 0
Approval date [1] 288940 0
11/02/2013
Ethics approval number [1] 288940 0
NTY/12/04/031

Summary
Brief summary
Since 1962 a network of lay experimental drug users have reported that ibogaine at high doses decreases opioid withdrawal symptoms in opioid dependent subjects. It is likely that the majority of the effects of ibogaine in humans are produced by the metabolite noribogaine rather than ibogaine itself. The conversion of ibogaine into noribogaine is mainly via an enzyme called CYP2D6. This enzyme belongs to the cytochrome P450 family and is involved in the metabolism of many drugs in the body. The study aims to characterize conversion of ibogaine to noribogaine based on measures of CYP2D6 activity, using single low doses of ibogaine dosed to healthy volunteers.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 38426 0
Prof Paul Glue
Address 38426 0
Psychological Medicine, Health Sciences Dunedin School of Medicine University of Otago
PO Box 913 Dunedin 9054
Country 38426 0
New Zealand
Phone 38426 0
64 3 470 3867
Fax 38426 0
Email 38426 0
Contact person for public queries
Name 38427 0
Ms Kira Garbe
Address 38427 0
Psychological Medicine, Health Sciences Dunedin School of Medicine University of Otago
PO Box 913 Dunedin 9054
Country 38427 0
New Zealand
Phone 38427 0
64 3 470 9451
Fax 38427 0
Email 38427 0
Contact person for scientific queries
Name 38428 0
Dr Helen Winter
Address 38428 0
School of Pharmacy, University of Otago
PO Box 913 Dunedin 9054
Country 38428 0
New Zealand
Phone 38428 0
64 3 479 7272
Fax 38428 0
Email 38428 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
EmbaseEffects of low dose ibogaine on subjective mood state and psychological performance.2016https://dx.doi.org/10.1016/j.jep.2016.05.022
EmbaseInfluence of CYP2D6 activity on the pharmacokinetics and pharmacodynamics of a single 20 mg dose of ibogaine in healthy volunteers.2015https://dx.doi.org/10.1002/jcph.471
N.B. These documents automatically identified may not have been verified by the study sponsor.