Condition category
Digestive System
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Prof David B A Silk


Contact details

Department of Gastroenterology & Nutrition
Central Middlesex Hospital
Acton Lane
NW10 7NS
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title


Study hypothesis

Irritable bowel syndrome (IBS) is the commonest functional gastrointestinal disorder. Symptoms occur in the absence of any demonstrable organic disease. Symptoms arise as a consequence of either abnormality of the intestinal motility or sensation or as a combination of the two. Abnormal small intestinal and colonic motility has been demonstrated in IBS patients. These may lead to the onset of pain as well as bloating and if the abnormal motility results in changes in intestinal transit, constipation and diarrhoea.

1. The principal research objective is to assess the tolerability of the new synthesised galacto-oligosaccharide prebiotic (B12GOS) in patients with irritable bowel syndrome (IBS), to evaluate the effect of B12GOS on the faecal microflora of patients with IBS, and to assess the effect of B12GOS on the concentration of colonic fermentation end products (short chain fatty acids) in the faecal samples of patients with IBS
2. To examine B12GOS efficacy verses placebo in IBS patients on the subjects global assessment of relief (SGA), severity of patient symptoms, stool frequency and consistency and quality of life

Ethics approval

Yes. Approved October 2005.

Study design

Interventional, single blind, randomised, stratified, parallel design

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet


Irritable bowel syndrome


Single blind, randomised, stratified, parallel design in patients with diarrhoea predominant IBS (D-IBS), constipation predominant IBS (C-IBS) and alternating IBS (A-IBS). The single blind nature of the trial is in order that the placebo can be administered in each case prior to the prebiotic.

Patients randomised to 1 of 3 groups. Design will then consist of an initial 2 week baseline period followed by 2 treatment periods of 4 weeks each, separated by a 2 week 'wash out' phase. During the 1st treatment period patients will be asked to drink once daily before breakfast either 7.0 g (2 groups) or 3.5 g (one group) chocolate or banana flavoured placebo. After the 2 week 'wash out' period patients will be asked to drink once daily, before breakfast, either 7.0 g or 3.5 g of chocolate or banana flavoured B12GOS, or 7.0 g chocolate or banana flavoured placebo. On day 1 patient numbers will be assigned and stratified according to D-IBS, C-IBS, A-IBS. Randomisation table to be obtained from the internet.

Intervention type



Not Specified

Drug names

Galacto-oligosaccharide prebiotic (B12GOS)

Primary outcome measure

To assess the tolerability of B12GOS in IBS patients and to assess the B12GOS-induced changes in:
1. The faecal microbiota of patients with IBS using culture independent methodology
2. The concentration of colonic fermentation end-products (short fatty acids) in the faecal samples

Secondary outcome measures

To examine the efficacy of B12GOS versus placebo on Subjects Global Assessment of relief (SGA), severity of patient symptoms, stool frequency and consistency and quality of life.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Only patients fulfilling the Rome II criteria for diagnosis of IBS will be included in the study. All will have normal haematological and biochemical indices and no abnormal findings on barium enema or colonoscopy undertaken within the previous five years. Patients will be categorised into diarrhoea predominant (D-IBS), constipation predominant (C-IBS) or altering sub groups of IBS (A-IBS) according to published criteria.

Participant type


Age group




Target number of participants

A total of 66 patients.

Participant exclusion criteria

1. Patients with evidence of organic disease of the gastrointestinal tract such as tumour, inflammatory bowel disease etc. as shown by endoscopic or radiological evaluation of the bowel within the previous 5 years
2. Patients with abnormal laboratory tests, positive stool cultures in patients with diarrhoea predominant IBS or abnormal proctoscopy or abdominal ultrasound which requires further investigation
3. Functional disorder of upper gastrointestinal tract for which treatment has not been stable for past three months
4. Use of other investigational drugs within prior month or intention to use such drugs during the course of the study
5. Intention to use regularly other medication or investigational agents that affect gastrointestinal motility
6. Ingestion of products containing pre- and or pro-biotics in the last two weeks before the trial commences
7. Received antibiotics in the previous three months

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Department of Gastroenterology & Nutrition
NW10 7NS
United Kingdom

Sponsor information


Clasado Ltd (UK)

Sponsor details

11 Warren Yard
Wolverton Mill
Milton Keynes
MK12 5NW
United Kingdom

Sponsor type




Funder type


Funder name

Clasado Ltd (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2009 results in

Publication citations

  1. Results

    Silk DB, Davis A, Vulevic J, Tzortzis G, Gibson GR, Clinical trial: the effects of a trans-galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome., Aliment. Pharmacol. Ther., 2009, 29, 5, 508-518, doi: 10.1111/j.1365-2036.2008.03911.x.

Additional files

Editorial Notes