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Trial registered on ANZCTR


Registration number
ACTRN12612000389808
Ethics application status
Approved
Date submitted
29/03/2012
Date registered
4/04/2012
Date last updated
15/09/2020
Date data sharing statement initially provided
15/09/2020
Date results information initially provided
15/09/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
An investigation into the cognitive effects and bioavailability of components of green tea.
Scientific title
An investigation into the cognitive effects and bioavailability of components of green tea in healthy adults.
Secondary ID [1] 280240 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cognitive function in healthy adults. 286196 0
Condition category
Condition code
Alternative and Complementary Medicine 286393 286393 0 0
Herbal remedies
Mental Health 286394 286394 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The investigation will employ a single centre, double-blind, placebo controlled, five-period crossover design with a 7-day washout period.

Participants will be required to attend one practice session followed by five testing sessions.
During the practice session particpants will sign the consent form and be familiarised with the mood scales and cognitive tasks.

The testing sessions will see participants taking one of four interventions:

1) Whole green tea extract standardised with regard to caffeine and catechins (‘GTE’). Extract to deliver 40 mg caffeine per dose,170 mgs catechins.
2) 40 mg synthetic caffeine (‘caffeine’)
3) Decaffeinated green tea extract (‘Decaff-GTE’) standardised with regard to catechins. Extract to deliver 0.12 mgs caffeine; 170 mgs catechins,
4) Catechins alone i.e. without any other components of green tea extract (‘catechins’). Extract to deliver 185 mgs catechins .
5) Placebo

All five treatments will be administered as capsules and will be matched for colour, smell and taste

Participants will be randomly allocated to receive either treatment (1) or (2) or (3) or (4) or (5) on their first testing day. This will be done by a randomised computer number sequence generator. Over the course of the investigation, they will complete all five treatments with treatment order counterbalanced across participants. A disinterested third party will be responsible for the blinding procedure.

On the testing days subjects will provide baseline blood and saliva samples then undergo baseline mood and cognitive assessment. The day’s treatment will be administered at 9.00 am +/- 30 min) followed exactly 30 min and 120 min later by the same mood and cognitive assessment (using parallel forms of stimuli). Final blood and saliva samples will be taken and subjects will leave the laboratory.
At the end of the final visit subjects will be fully debriefed before leaving the laboratory.

There will be a seven day washout period between each testing session
Intervention code [1] 284586 0
Treatment: Other
Comparator / control treatment
Treatment (5): 4 X 150mg Avicel microcrystalline cellulose capsules This is a cross over design, so all participants will be administered all treatments on different testing days separated by a one week wash out period.
Control group
Placebo

Outcomes
Primary outcome [1] 286849 0
Cognitive Performance using computerised measures aimed at evaluating attentional processes.
Timepoint [1] 286849 0
Baseline, 30 minutes post treatment and 120 minutes post treatment.
Primary outcome [2] 286850 0
Mood as assessed by the following questionnaires:

Bond&Lader Visual analogue mood scales
Caffeine Research Visual Analogue scales
Stress and Fatigue Visual Analogue Mood Scales (VAMS)
Timepoint [2] 286850 0
Baseline, 50 minutes post treatment and 140 minutes post treatment.
Secondary outcome [1] 296806 0
Serum levels of catechins and caffeine to assess the relationship between any behavioural change and levels of active components of green tea extract.

These levels will be measued by analysing venous blood collected via a vacutainer following standard phlebotomy procedures.
Timepoint [1] 296806 0
Baseline and 148 minutes post treatment

Eligibility
Key inclusion criteria
People who meet the following inclusion criteria will be included in the trial:
1. Male or female.
2. Aged 18-40 years.
3. Willing and able to provide written informed consent.
4. Understands and is willing and able to comply with all study procedures.
5. Are in good general health with no history of psychiatric disease.
6. Regular caffeine consumers (between 1-4 cups of coffee per day most days)
7. Must have corrected to normal vision
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Subjects who display any of the following will be excluded from the trial:
1.Females who are pregnant/lactating and/or not using a medically approved form of contraception.
2. Any significant concurrent illness including any bleeding disorders, heart conditions, diabetes, glaucoma, high blood pressure or osteoporosis.
3. Individuals who suffer from Diabetes Mellitus or diagnosed with Phenylketonuria (PKU).
4. Any known or suspected food allergies (this would cover all ingredients in the investigational product).
5. Susceptible to any unwanted side-effects of caffeine, such as reduction in sleep quality.
6. Smokers and users of recreational drugs (except alcohol and other food grade actives)
7. Have participated in any other study involving an investigational product in the last 4 weeks.

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)
A unique screening number will identify each subject screened for study participation. Screening numbers will be assigned in ascending numerical order according to appearance at the study site. Subjects who meet all inclusion and exclusion criteria will be randomised according to the randomisation schedule generated by the Biostatistics and Data Management Department of GSKCH using computer software.
\
Two copies of the randomisation codes will be kept; one for administration purposes and one for emergency code break situations. Whilst the investigation is a double blind trial, investigators will know the whereabouts of, and have access to, this information. This is in case of an emergency where the contents of the treatment used may need to be known.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Subjects will be randomised using a randomisation table created by computer software (computerised sequence generation).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
The investigation will employ a single centre, double-blind, placebo controlled, five-period crossover design with a 7-day washout period.

Participants will be randomly allocated to a treatment sequence and will cycle through the 5 study treatments in the order specified in the randomisation schedule
Phase
Phase 4
Type of endpoint/s
Efficacy
Statistical methods / analysis

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 in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 31272 0
3122 - Hawthorn

Funding & Sponsors
Funding source category [1] 285004 0
Commercial sector/Industry
Name [1] 285004 0
GlaxoSmithKline Nutritional Healthcare
Country [1] 285004 0
United Kingdom
Primary sponsor type
Commercial sector/Industry
Name
GlaxoSmithKline Nutritional Healthcare
Address
Address: GSK House, AS1
980 Great West Road
Brentford
Middlesex TW8 9GS
UK
Country
United Kingdom
Secondary sponsor category [1] 283869 0
None
Name [1] 283869 0
Address [1] 283869 0
Country [1] 283869 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 287012 0
Swinburne University Human Research Ethics Committee
Ethics committee address [1] 287012 0
PO Box 218
Hawthorn VIC 3122
Ethics committee country [1] 287012 0
Australia
Date submitted for ethics approval [1] 287012 0
09/12/2011
Approval date [1] 287012 0
27/04/2012
Ethics approval number [1] 287012 0
2011/284

Summary
Brief summary
This research project is aiming to determine the effects of green tea and combinations of potential active components of green tea (caffeine and catechins) on cognitive function and mood.

This project will assess the effectiveness of green tea extract and different fractions of green tea extract on cognitive function (primarily attention) and mood measures. The plasma levels of several potential active constituents of green tea will also be monitored.

Subjects will be required to attend five testing sessions (and one practice session). Subjects will take one intervention (administered in capsule format) at each session.

1. Whole green tea extract standardised with regard to caffeine and catechins (‘GTE’). Extract to deliver 40 mg caffeine per dose.
2. 40 mg synthetic caffeine (‘caffeine’)
3. Decaffeinated green tea extract (‘Decaff-GTE’) standardised with regard to catechins
4. Catechins alone i.e. without any other components of green tea extract (‘catechins’)
5. Placebo
Trial website
Trial related presentations / publications
Results were not published.
Public notes

Contacts
Principal investigator
Name 33997 0
Prof Andrew Scholey
Address 33997 0
Centre for Human Psychopharmacology
Swinburne University
H24, Po Box 218 Hawthorn, Vic, 3122
Country 33997 0
Australia
Phone 33997 0
+613 9214 8932
Fax 33997 0
Email 33997 0
Contact person for public queries
Name 17244 0
Mrs Tinette Goh
Address 17244 0
H24, Po Box 218
Hawthorn, Vic, 3122
Country 17244 0
Australia
Phone 17244 0
613 92145094
Fax 17244 0
Email 17244 0
Contact person for scientific queries
Name 8172 0
Prof Professor Andrew Scholey
Address 8172 0
H24, Po Box 218
Hawthorn, Vic, 3122
Country 8172 0
Australia
Phone 8172 0
613 9214 8932
Fax 8172 0
Email 8172 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


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
No additional documents have been identified.