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Trial registered on ANZCTR


Registration number
ACTRN12621000149864
Ethics application status
Approved
Date submitted
16/12/2020
Date registered
15/02/2021
Date last updated
15/08/2023
Date data sharing statement initially provided
15/02/2021
Date results information initially provided
8/08/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
The effects of the herbal preparation, STW5-II, on proximal gastric relaxation in healthy volunteers.
Scientific title
The effects of the herbal preparation, STW5-II, on proximal gastric relaxation in healthy volunteers.
Secondary ID [1] 303026 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Functional Dyspepsia 320101 0
Condition category
Condition code
Oral and Gastrointestinal 318034 318034 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This trial will observe the physiological gastrointestinal responses to a single dose (20 drops, 1.1 ml) of STW5-II, vs placebo, to investigate the mechanisms by which this herbal preparation may exert its gastrointestinal symptom relieving effects.

Two study visits, separated by at least four days, are required. Each visit will take approximately four hours. Participants will receive, in randomised, double-blind fashion, oral administration of either (i) 20 drops (1.1ml) of STW5-II or (ii) 20 drops (1.1ml) control solution (i.e. containing no active ingredients). For both study visits, participants will fast for ~14 hrs overnight, and abstain from alcohol and vigorous exercise for 24 hrs prior to each visit. On each study day, participants will attend the Clinical Research Facility, Adelaide Medical School, Adelaide Health and Medical Sciences (AHMS) Building at 8:30am.

Upon arrival, the participant will be intubated with an orogastric catheter. The catheter will be a double-lumen polyvinyl tube (outer diameter: 3.5 mm), which has a flaccid, thin-walled, compliant polyethylene bag (max. capacity 1200 ml) tied onto and tightly wrapped around its distal end. The catheter will be connected to a barostat device, which consists of a strain-gauge linked by an electronic relay to an air aspiration / injection system. The barostat device measures changes in gastric volume at a fixed pressure. Thus, when the gastric wall relaxes, air is injected into the bag to maintain the pressure, whereas air is withdrawn when the stomach contracts. The catheter will be inserted through the mouth and the bag positioned in the fundus of the stomach by inflating it with ~300-400 ml of air, carefully pulling it back until its passage is restricted by the lower oesophageal sphincter and then pushing it back in again by 3 cm. The minimal distending pressure (MDP) will then be determined by gradually increasing intragastric pressure in 1 mmHg steps. The MDP is defined as the intrabag pressure which first results in a bag volume of 30 ml air and is necessary to overcome the intra-abdominal pressure. Intra-bag pressure will then be set at 2 mmHg above the MDP and baseline intragastric pressure will be monitored until it is stable for 10 min.
Following this, participants will ingest 50 ml of water with either (i) STW5-II or (ii) control solution (as stated previously). Complete ingestion of 50 ml of water and STW5-II or placebo will be confirmed by the investigator. Gastric relaxation (i.e. the volume increase in the bag at the set pressure) in response to the treatment will be recorded for 180 min. The participant will be asked to complete a VAS questionnaire to assess GI symptoms (e.g. fullness, nausea, bloating) at baseline, and then at 15-min intervals. These scales consist of a horizontal line, 100 mm long, on which the participant places a vertical mark across the line, indicating the strength of each symptom felt at that time, with 0 mm indicating that the symptom is not felt and 100 mm that the symptom is extremely strong. At 180 min, the catheter will be removed, and the participant offered a light lunch after which they will be free to leave the laboratory.
Intervention code [1] 319656 0
Treatment: Other
Comparator / control treatment
20 drops (1.1 ml) Ethanolic liquic
Control group
Placebo

Outcomes
Primary outcome [1] 326023 0
Maximum intrabag volume.

Intrabag volumes will recorded using a gastric barostat with a computer-based system running commercially available software (Protocol PlusTM, G & J Electronics, Toronto, Ontario, Canada).
Timepoint [1] 326023 0
Intrabag volumes will be measured continuously, at baseline (i.e., t = –10 to 0 min), and between t = 0 and t = 180 min.
The maximum volume will be calculated by determining the highest volume, and time point at which this occurred, in each subject.
Primary outcome [2] 332236 0
Intra-bag volume. Intrabag volumes will recorded using a gastric barostat with a computer-based system running commercially available software (Protocol PlusTM, G & J Electronics, Toronto, Ontario, Canada).
Timepoint [2] 332236 0
Volumes will be determined during baseline, and for each 10 min segment during t = 0 to 180 min.
Secondary outcome [1] 389904 0
Appetite sensations (hunger, fullness, desire to eat, amount of food the subject thinks they could eat) and gastrointestinal symptoms (nausea, bloating). This is a composite outcome.

Measurements will use a 100mm Visual Analogue Scale (VAS).
Timepoint [1] 389904 0
VAS measurements will be taken at baseline (-10 min) and at 15 min intervals between t = 0 and 180 min.

Eligibility
Key inclusion criteria
Healthy, lean (BMI: 19-25 kg/m2) male and female volunteers will be included. Participants will be required to be weight-stable (ie <5% fluctuation) at study entry. Females will be required to be premenopausal and studied during the follicular phase of the menstrual cycle.
Minimum age
18 Years
Maximum age
60 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Each participant will be questioned prior to the study to exclude:
- regular GI symptoms, as measured by the GI symptom score (score >1 for any component), or significant GI disease or surgery
- use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may affect energy metabolism, GI function, body weight or appetite (eg domperidone, anticholinergic drugs (eg atropine), metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, Astragalus, St Johns Wort etc.)
- regular medication that cannot be discontinued during the study
- lactose intolerance/other food allergy, or allergy to any of the ingredients of STW5-II
- current gallbladder or pancreatic disease
- cardiovascular or respiratory diseases
- epilepsy
- any other illnesses as assessed by the investigator (including chronic illnesses not explicitly listed above)
- high performance athletes
- current intake of > 2 standard drinks on > 5 days per week
- current smokers/users of tobacco products (including pipe, chewing, cigarettes, cigars, sheesha, vaping)
- recreational drug use (e.g marijuana)
- current intake of any illicit substance
- vegetarians
- inability to tolerate oro-gastric tube
- inability to comprehend study protocol
- in female participants, pregnancy, lactation or surgical sterilisation (a pregnancy test will be performed, using a urine sample, prior to each study day)

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)
Numbered containers
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 administering 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
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)
SA

Funding & Sponsors
Funding source category [1] 307436 0
Commercial sector/Industry
Name [1] 307436 0
Steigerwald Arzneimittelwerk GmbH
Country [1] 307436 0
Germany
Primary sponsor type
University
Name
University of Adelaide
Address
North Terrace,
Adelaide 5005,
South Australia
Country
Australia
Secondary sponsor category [1] 308110 0
Individual
Name [1] 308110 0
Professor Christine Feinle-Bisset
Address [1] 308110 0
Level 5, Adelaide Health and Medical Sciences Building,
Cnr North Terrace and George Street,
Adelaide 5005,
South Australia
Country [1] 308110 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 307517 0
Central Adelaide Local Health Network Human Research Ethics Committee
Ethics committee address [1] 307517 0
L3 Roma Mitchell Building,
136 North Terrace,
Adelaide 5000,
South Australia
Ethics committee country [1] 307517 0
Australia
Date submitted for ethics approval [1] 307517 0
Approval date [1] 307517 0
31/08/2020
Ethics approval number [1] 307517 0

Summary
Brief summary
This trial will observe the physiological gastrointestinal responses to a single dose (20 drops, 1.1 ml) of STW5-II, vs placebo, to investigate the mechanisms by which this herbal preparation may exert its gastrointestinal symptom relieving effects.
Participants will attend two visits at which they will receive either STW5-II or placebo, and gastric relaxation will be measured for the following three hours. The hypothesis is that STW5-II will increase proximal gastric relation.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 107522 0
Prof Christine Feinle-Bisset
Address 107522 0
University of Adelaide,
Level 5, Adelaide Health and Medical Sciences Building,
Cnr North Terrace and George St,
Adelaide 5005.
South Australia
Country 107522 0
Australia
Phone 107522 0
+61 8 8313 6053
Fax 107522 0
Email 107522 0
Contact person for public queries
Name 107523 0
Prof Christine Feinle-Bisset
Address 107523 0
University of Adelaide,
Level 5, Adelaide Health and Medical Sciences Building,
Cnr North Terrace and George St,
Adelaide 5005,
South Australia
Country 107523 0
Australia
Phone 107523 0
+61 8 8313 6053
Fax 107523 0
Email 107523 0
Contact person for scientific queries
Name 107524 0
Prof Christine Feinle-Bisset
Address 107524 0
University of Adelaide,
Level 5, Adelaide Health and Medical Sciences Building,
Cnr North Terrace and George St,
Adelaide 5005,
South Australia
Country 107524 0
Australia
Phone 107524 0
+61 8 8313 6053
Fax 107524 0
Email 107524 0

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


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Plain language summaryNo STW5-II increased proximal gastric volumes in the ... [More Details]

Documents added automatically
No additional documents have been identified.