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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/ct2/show/NCT05682339




Registration number
NCT05682339
Ethics application status
Date submitted
29/12/2022
Date registered
12/01/2023
Date last updated
1/12/2023

Titles & IDs
Public title
Effects of Intragastric Quinine, Alone or Combined With L-isoleucine, on Postprandial Glycaemic Control
Scientific title
Effects of Intragastric Quinine, Alone or Combined With L-isoleucine, on Postprandial Glycaemic Control
Secondary ID [1] 0 0
R20161005
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Healthy 0 0
Condition category
Condition code

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - Quinine
Other interventions - L-isoleucine
Other interventions - Combination of quinine and L-isoleucine
Other interventions - Control

Active Comparator: Quinine only - In this arm, participants will receive a 10 ml intragastric bolus of 300 mg quinine followed 30 min later by 100 ml intragastric bolus of control for L-isoleucine.

Active Comparator: L-isoleucine only - In this arm, participants will receive a 10 ml intragastric bolus of control for quinine followed 30 min later by 100 ml intragastric bolus of 5 g L-isoleucine.

Active Comparator: Quinine + L-isoleucine - In this arm participants will receive a 10 ml intragastric bolus of 300 mg quinine followed 30 min later by 100 ml intragastric bolus of 5 g L-isoleucine.

Placebo Comparator: Control - In this arm, participants will receive a 10 ml intragastric bolus of control solution followed 30 min later by 100 ml intragastric bolus of control solution.


Other interventions: Quinine
Quinine, which is a bitter compound, extracted from the bark of the cinchona tree and has been shown in our previous studies to lower blood glucose in doses of 300-600 mg, will be 'active' in this condition.

Other interventions: L-isoleucine
L-isoleucine, which is a branched-chain amino acid, and one of the building blocks of protein, therefore is part of our daily diet, will be 'active' in this condition.

Other interventions: Combination of quinine and L-isoleucine
In this condition, both quinine and L-isoleucine will be administered as 'active'.

Other interventions: Control
In the condition, where quinine is 'active', control for L-isoleucine (5 ml oraplus and 95 ml saline) will be administered. In the condition, where L-isoleucine will be 'active', control for quinine (10 ml distilled water) will be administered.
Whereas, in a control condition, both for quinine and L-isoleucine, a control solution will be administered.
Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Change from baseline plasma glucose concentration after a mixed-nutrient drink for 3 hours
Timepoint [1] 0 0
Blood samples will be taken repeatedly within each study visit (i.e. at baseline (t= 0 min), after administration of study treatments (t= -45, -30, -15 min) and after a mixed-nutrient drink (t= 0, 15, 30, 45, 60, 90, 120 and 180 min).
Secondary outcome [1] 0 0
Gastric emptying of a mixed nutrient drink
Timepoint [1] 0 0
Breath samples will be taken repeatedly on each study visit (i.e. t= 0 (baseline), 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 75, 90, 105,120, 135, 150, 165, 180 minutes) to construct a gastric emptying profile on each day.
Secondary outcome [2] 0 0
Plasma concentration of insulin after a mixed-nutrient drink
Timepoint [2] 0 0
Blood samples will be taken repeatedly within each study visit (i.e. at baseline (t= 0 min), after administration of study treatments (t= -45, -30, -15 min) and after a mixed-nutrient drink (t= 0, 15, 30, 45, 60, 90, 120 and 180 min).
Secondary outcome [3] 0 0
Plasma concentration of glucagon after a mixed-nutrient drink
Timepoint [3] 0 0
Blood samples will be taken repeatedly within each study visit (i.e. at baseline (t= 0 min), after administration of study treatments (t= -45, -30, -15 min) and after a mixed-nutrient drink (t= 0, 15, 30, 45, 60, 90, 120 and 180 min).
Secondary outcome [4] 0 0
Plasma concentration of glucagon-like peptide-1 (GLP-1) after a mixed-nutrient drink
Timepoint [4] 0 0
Blood samples will be taken repeatedly within each study visit (i.e. at baseline (t= 0 min), after administration of study treatments (t= -45, -30, -15 min) and after a mixed-nutrient drink (t= 0, 15, 30, 45, 60, 90, 120 and 180 min).
Secondary outcome [5] 0 0
Appetite-related perceptions (fullness, hunger, desire to eat, prospective food consumption) and gastrointestinal symptoms (nausea and bloating)
Timepoint [5] 0 0
VAS ratings will be collected repeatedly within each study visit (i.e. at baseline (t = 0 min), after administration of study treatments (t= -45, -30, -15 min) and after mixed-nutrient drink (t= 0, 15, 30, 45, 60, 90, 120 and 180 min).

Eligibility
Key inclusion criteria
- Lean weight (BMI 19-25 kg/m2)
Minimum age
18 Years
Maximum age
55 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Significant gastrointestinal symptoms, disease or surgery;

- Current gallbladder or pancreatic disease;

- Cardiovascular or respiratory diseases;

- Any other illnesses as assessed by the investigator (including chronic illnesses not
explicitly listed above);

- Use of prescribed or non-prescribed medications (including vitamins and herbal
supplements) which may affect energy metabolism, gastrointestinal function, bodyweight
or appetite (eg domperidone and cisapride, anticholinergic drugs (eg atropine),
metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, Astragalus, St
Johns Wort etc.);

- Individuals with low ferritin levels (less than 30 ng/mL), or who have donated blood
in the 12 weeks prior to taking part in the study;

- Lactose intolerance/other food allergy(ies);

- Vegetarians;

- Restrained eaters (score >12 on the three-factor eating questionnaire);

- Current intake of greater than 2 standard drinks on greater than 5 days per week;

- Current smokers of cigarettes/cigars/marijuana;

- Current intake of any illicit substance;

- High performance athletes;

- Inability to comprehend study protocol;

- Unable to tolerate naso-gastric tube

Study design
Purpose of the study
Other
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
19/06/2023
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
1/08/2024
Actual
Sample size
Target
16
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA
Recruitment hospital [1] 0 0
Clinical Research Facility, Adelaide Health and Medical Sciences Building - Adelaide
Recruitment postcode(s) [1] 0 0
5005 - Adelaide

Funding & Sponsors
Primary sponsor type
Other
Name
University of Adelaide
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
In this study, participants will receive, in randomized, double-blind fashion, an
intragastric bolus administration of either (i) 300 mg quinine, (ii) 5 g L-isoleucine, (iii)
a combination of (i)+(ii), or (iv) control, before 350 ml (500 kcal) of a mixed-nutrient
drink, to evaluate the effects on postprandial blood glucose, gastric emptying, and the
hormone, and appetite, responses to the mixed-nutrient drink. Study visits will be separated
by 3-7 days and participants will receive one treatment per visit.

On each study visit, the participant will be intubated with a nasogastric feeding tube. At t=
- 60 min (08:30 am), a baseline blood sample, visual analogue scale questionnaire (VAS), and
breath sample will be collected and quinine or control will be administered through the
feeding tube. 30 min later (at t= - 30 min), L-isoleucine or control will be administered
over 2 min after which the feeding tube will be removed immediately. At t = -45, -30, -15,
and -1 min further blood samples will be collected and VAS completed. At t = -1 min,
participants will consume, within 1 minute, a mixed-nutrient drink, labeled with 100 mg of
1-13C-acetate for measurement of gastric emptying by breath sampling. Blood samples, VAS, and
breath samples will be taken at regular intervals between t = 0-180 min.
Trial website
https://clinicaltrials.gov/ct2/show/NCT05682339
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Christine Feinle-Bisset, PhD
Address 0 0
University of Adelaide, Adelaide, South Australia
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Christine Feinle-Bisset, PhD
Address 0 0
Country 0 0
Phone 0 0
+61 8 8313 6053
Fax 0 0
Email 0 0
christine.feinle@adelaide.edu.au
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/ct2/show/NCT05682339