ClinicalTrials.gg
Not yet recruitingNCT07439978ProbioticsUpdated May 8, 2026

Encapsulated Probiotics & Gut Microbiota

A Phase 1 interventional study of probiotic containing L.rhamnosus R0011 strain and 200 ml yogurt drink in Colonization, Asymptomatic and Colonisation, sponsored by University College Dublin. Not yet recruiting. Open to participants aged 25 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-08.

Sponsored by University College Dublin · Phase 1, Interventional, and Treatment

From the registry’s dates

  • Primary completion was expected by Jun 2026, 5 months ago, but the record still lists the study as not yet recruiting.
Phase
Phase 1
Study type
Interventional
Enrollment
50
Allocation
Randomized
Ages
25 Years to 65 Years
Sex
All
01

Study summary

The aim of this study is to determine whether encapsulation of probiotic bacteria using natural plant protein can enhance bacterial colonisation. Lactobacillus rhamnosus is an ideal strain for the intervention, as it has been shown to affect overall gut health, gut-brain axis, and brain function.

Twenty-five participants aged 25 to 65 years will be recruited and assessed on four occasions to compare the blood and faecal effects of a 28-day ingestion of a yoghurt beverage with and without the probiotic strain of interest. The study window will be 70+/13 days.

The current study will provide important information on the physiological function of probiotics in the small bowel. Understanding the underlying physiological effects of targeted probiotic delivery to the intestine and the impact on the microbiome is important for health outcomes.

Read the detailed description

The investigators plan to assess the gut microbiome and changes in probiotic diversity at the end of a course of a beverage containing encapsulated Lacticaseibacillus rhamnosus, compared to those at the end of a course of the same beverage without probiotics.

This is a randomised, double-blinded, placebo-controlled crossover study. Twenty-five healthy men and women with a body mass index (BMI) between 18.5-31.9 kg/m2, aged 25-65 years, will be recruited and randomised to a commercial fermented (yoghurt) drink containing a) encapsulated probiotics consisting of Lacticaseibacillus rhamnosus, or b) a non-probiotic fermented (yoghurt) dairy drink (control). The number of participants includes a 10% drop-out rate.

Each participant will be studied on four occasions in random order following a crossover design. Each will receive a 200 ml beverage containing yoghurt per day for 28 days, either a) fortified with 1 billion probiotics contained in pea protein capsules or b) the control beverage (same yoghurt without probiotic). Faecal samples will be collected on four occasions: at baseline, and at 28, 42 and 70 days after baseline.

The current study will provide important information on the physiological function of probiotics in metabolic and inflammatory biochemical parameters, as well as in their capacity to colonise the gastrointestinal tract.

02

Conditions studied

  • Colonization, Asymptomatic
  • Colonisation

Keywords

  • Probiotic
  • Microbiota
  • Colonization
  • Dairy
03

In context

Asymptomatic Infections

32 studies on the registry are indexed under Asymptomatic Infections; 6 are open to participants now.

This study's planned enrollment of 50 is below the median of 79 across 20 interventional studies indexed under Asymptomatic Infections.

Browse Asymptomatic Infections studies →

Lead sponsor

University College Dublin is the lead sponsor of 113 studies on the registry; 32 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
25 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Capacity to obtain and sign before any study-related procedure
  • range 18.5-31.9 kg/m2
  • Willing to abstain from regular consumption of probiotic supplements or food products containing probiotic bacteria (including fermented food and beverages).
  • Willing to abstain from regular consumption of supplements and medications known to alter gastrointestinal function or inflammatory status during the study.

Exclusion criteria

Exclusion Criteria:

Participants who meet any of the following criteria will be excluded:

  • Smoking
  • Substance abuse
  • Pregnancy
  • Diagnosis of type 1 and/or type 2 diabetes
  • Current (or within the last 4 weeks prior to study start) use of probiotic supplementation.
  • Immobile (defined as the inability to participate in all study-related procedures)
  • History of complicated gastrointestinal surgery
  • Diagnosed with inflammatory bowel disease (IBD)
  • Current diagnosis of psychiatric disease/s or syndromes
  • Current diagnosis of neurodegenerative disease
  • Systemic use of antibiotics and/or medication in the last 4 months prior to inclusion
  • Use of any non-steroidal anti-inflammatory drug (NSAID) more than 3 times a week for the last 2 months
  • Consumption of any NSAID within 7 days of study start
  • Any condition which could substantially interfere with intestinal barrier function (e.g. gluten sensitivity, lactose intolerance, celiac disease, IBS, IBD) or in any other way with the outcome of the study, as decided by the principal investigator's discretion
  • Regular smoking, use of snuff, nicotine, cannabidiol narcotics/supplements, or e-cigarette use
  • Drinking more than 9 standard cups of alcohol per week and/or more than 3 standard cups of alcohol per occasion
  • Regular use, for more than three times a week for the last 2 months and/or 7 days prior to inclusion, of medications which, according to the principal investigator, can have an anti-inflammatory effect or affect in any way the intestinal barrier function or have an impact on the study analysis (such as laxatives, anti-diarrheal, anti-cholinergic, etc.)
  • After being included in the study, starting any medication or treatment that could potentially influence the study participation and/or study analysis.
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Single (Participant)
Enrollment
50 participants (estimated)

Study arms

  • Experimental
    Probiotic drink

    Encapsulated Lacticaseibacillus rhamnosus in 200 ml Yogurt drink

    Biological: probiotic containing L.rhamnosus R0011 strain

  • Placebo comparator
    Placebo drink

    200 ml yogurt drink

    Dietary Supplement: 200 ml yogurt drink

Interventions

  • Biologicalprobiotic containing L.rhamnosus R0011 strain

    Twenty-five participants will be studied on four occasions in random order and in a crossover design. Subjects will receive a daily dose of 200 ml on two different occasions for 28 days, a commercial dairy drink fortified with 1Billion probiotics in the pea protein capsules. Feacal samples will be collected on four occasions: at baseline, 28 days after baseline, 42 days and 70 days after baseline.

  • Dietary supplement200 ml yogurt drink

    Twenty-five participants will be studied on four occasions in random order and in a crossover design. Subjects will receive a daily dose 200 ml on two different occasions for 28 days, a commercial dairy drink (no probiotics). Feacal samples will be collected on four occasions: at baseline, 28 days after baseline, 42 days and 70 days after baseline.

06

What researchers measure

Primary outcomes

  1. Colonisation

    Faecal abundance of Lactobacillus rhamnosus after probiotic consumption measured through shotgun metagenomics -libraries with Illumina Nextera XT, sequenced 150 bp paired-end on NextSeq 2000. Negative + positive controls will be processed alongside study samples with around 15M paired reads/sample after quality controls.

    Time frame: 28 days

07

Study locations

No study locations are listed for this record.

08

References and documents

Publications

  • Zhou JS, Shu Q, Rutherfurd KJ, Prasad J, Gopal PK, Gill HS. Acute oral toxicity and bacterial translocation studies on potentially probiotic strains of lactic acid bacteria. Food Chem Toxicol. 2000 Feb-Mar;38(2-3):153-61. doi: 10.1016/s0278-6915(99)00154-4. PubMed 10717355 ↗
  • Zhou JS, Shu Q, Rutherfurd KJ, Prasad J, Birtles MJ, Gopal PK, Gill HS. Safety assessment of potential probiotic lactic acid bacterial strains Lactobacillus rhamnosus HN001, Lb. acidophilus HN017, and Bifidobacterium lactis HN019 in BALB/c mice. Int J Food Microbiol. 2000 May 25;56(1):87-96. doi: 10.1016/s0168-1605(00)00219-1. PubMed 10857928 ↗
  • Zhou JS, Pillidge CJ, Gopal PK, Gill HS. Antibiotic susceptibility profiles of new probiotic Lactobacillus and Bifidobacterium strains. Int J Food Microbiol. 2005 Feb 1;98(2):211-7. doi: 10.1016/j.ijfoodmicro.2004.05.011. PubMed 15681048 ↗
  • Zheng Y, Yu Z, Zhang W, Sun T. Lactobacillus rhamnosus Probio-M9 Improves the Quality of Life in Stressed Adults by Gut Microbiota. Foods. 2021 Oct 8;10(10):2384. doi: 10.3390/foods10102384. PubMed 34681433 ↗
  • Zahr NM, Mayer D, Pfefferbaum A, Sullivan EV. Low striatal glutamate levels underlie cognitive decline in the elderly: evidence from in vivo molecular spectroscopy. Cereb Cortex. 2008 Oct;18(10):2241-50. doi: 10.1093/cercor/bhm250. Epub 2008 Jan 29. PubMed 18234683 ↗
  • Yao M, Xie J, Du H, McClements DJ, Xiao H, Li L. Progress in microencapsulation of probiotics: A review. Compr Rev Food Sci Food Saf. 2020 Mar;19(2):857-874. doi: 10.1111/1541-4337.12532. Epub 2020 Feb 11. PubMed 33325164 ↗
  • Wu D, Lewis ED, Pae M, Meydani SN. Nutritional Modulation of Immune Function: Analysis of Evidence, Mechanisms, and Clinical Relevance. Front Immunol. 2019 Jan 15;9:3160. doi: 10.3389/fimmu.2018.03160. eCollection 2018. PubMed 30697214 ↗
  • World Medical Association. World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects. JAMA. 2013 Nov 27;310(20):2191-4. doi: 10.1001/jama.2013.281053. No abstract available. PubMed 24141714 ↗
  • Wickens KL, Barthow CA, Murphy R, Abels PR, Maude RM, Stone PR, Mitchell EA, Stanley TV, Purdie GL, Kang JM, Hood FE, Rowden JL, Barnes PK, Fitzharris PF, Crane J. Early pregnancy probiotic supplementation with Lactobacillus rhamnosus HN001 may reduce the prevalence of gestational diabetes mellitus: a randomised controlled trial. Br J Nutr. 2017 Mar;117(6):804-813. doi: 10.1017/S0007114517000289. Epub 2017 Apr 3. PubMed 28367765 ↗
  • Rode J, Edebol Carlman HMT, Konig J, Repsilber D, Hutchinson AN, Thunberg P, Andersson P, Persson J, Kiselev A, Lathrop Stern L, Salomon B, Mohammed AA, Labus JS, Brummer RJ. Probiotic Mixture Containing Lactobacillus helveticus, Bifidobacterium longum and Lactiplantibacillus plantarum Affects Brain Responses Toward an Emotional Task in Healthy Subjects: A Randomized Clinical Trial. Front Nutr. 2022 Apr 29;9:827182. doi: 10.3389/fnut.2022.827182. eCollection 2022. PubMed 35571902 ↗
  • Moro-Garcia MA, Alonso-Arias R, Baltadjieva M, Fernandez Benitez C, Fernandez Barrial MA, Diaz Ruisanchez E, Alonso Santos R, Alvarez Sanchez M, Saavedra Mijan J, Lopez-Larrea C. Oral supplementation with Lactobacillus delbrueckii subsp. bulgaricus 8481 enhances systemic immunity in elderly subjects. Age (Dordr). 2013 Aug;35(4):1311-26. doi: 10.1007/s11357-012-9434-6. Epub 2012 May 30. PubMed 22645023 ↗
  • Hutchinson AN, Bergh C, Kruger K, Susserova M, Allen J, Ameen S, Tingo L. The Effect of Probiotics on Health Outcomes in the Elderly: A Systematic Review of Randomized, Placebo-Controlled Studies. Microorganisms. 2021 Jun 21;9(6):1344. doi: 10.3390/microorganisms9061344. PubMed 34205818 ↗
  • Gbassi GK, Vandamme T. Probiotic encapsulation technology: from microencapsulation to release into the gut. Pharmaceutics. 2012 Feb 6;4(1):149-63. doi: 10.3390/pharmaceutics4010149. PubMed 24300185 ↗
  • Claesson MJ, Jeffery IB, Conde S, Power SE, O'Connor EM, Cusack S, Harris HM, Coakley M, Lakshminarayanan B, O'Sullivan O, Fitzgerald GF, Deane J, O'Connor M, Harnedy N, O'Connor K, O'Mahony D, van Sinderen D, Wallace M, Brennan L, Stanton C, Marchesi JR, Fitzgerald AP, Shanahan F, Hill C, Ross RP, O'Toole PW. Gut microbiota composition correlates with diet and health in the elderly. Nature. 2012 Aug 9;488(7410):178-84. doi: 10.1038/nature11319. PubMed 22797518 ↗
  • Hill C, Guarner F, Reid G, Gibson GR, Merenstein DJ, Pot B, Morelli L, Canani RB, Flint HJ, Salminen S, Calder PC, Sanders ME. Expert consensus document. The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic. Nat Rev Gastroenterol Hepatol. 2014 Aug;11(8):506-14. doi: 10.1038/nrgastro.2014.66. Epub 2014 Jun 10. PubMed 24912386 ↗
  • Halverson T, Alagiakrishnan K. Gut microbes in neurocognitive and mental health disorders. Ann Med. 2020 Dec;52(8):423-443. doi: 10.1080/07853890.2020.1808239. Epub 2020 Aug 31. PubMed 32772900 ↗
  • Gill HS, Rutherfurd KJ, Cross ML. Dietary probiotic supplementation enhances natural killer cell activity in the elderly: an investigation of age-related immunological changes. J Clin Immunol. 2001 Jul;21(4):264-71. doi: 10.1023/a:1010979225018. PubMed 11506196 ↗
  • Costabile A, Bergillos-Meca T, Rasinkangas P, Korpela K, de Vos WM, Gibson GR. Effects of Soluble Corn Fiber Alone or in Synbiotic Combination with Lactobacillus rhamnosus GG and the Pilus-Deficient Derivative GG-PB12 on Fecal Microbiota, Metabolism, and Markers of Immune Function: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study in Healthy Elderly (Saimes Study). Front Immunol. 2017 Dec 12;8:1443. doi: 10.3389/fimmu.2017.01443. eCollection 2017. PubMed 29312280 ↗
  • Christensen SE, Moller E, Bonn SE, Ploner A, Wright A, Sjolander A, Balter O, Lissner L, Balter K. Two new meal- and web-based interactive food frequency questionnaires: validation of energy and macronutrient intake. J Med Internet Res. 2013 Jun 5;15(6):e109. doi: 10.2196/jmir.2458. PubMed 23739995 ↗
  • Anderson LA, Goodman RA, Holtzman D, Posner SF, Northridge ME. Aging in the United States: opportunities and challenges for public health. Am J Public Health. 2012 Mar;102(3):393-5. doi: 10.2105/AJPH.2011.300617. Epub 2012 Jan 19. No abstract available. PubMed 22390500 ↗
  • Bjelland I, Dahl AA, Haug TT, Neckelmann D. The validity of the Hospital Anxiety and Depression Scale. An updated literature review. J Psychosom Res. 2002 Feb;52(2):69-77. doi: 10.1016/s0022-3999(01)00296-3. PubMed 11832252 ↗
  • Betzel RF, Byrge L, He Y, Goni J, Zuo XN, Sporns O. Changes in structural and functional connectivity among resting-state networks across the human lifespan. Neuroimage. 2014 Nov 15;102 Pt 2:345-57. doi: 10.1016/j.neuroimage.2014.07.067. Epub 2014 Aug 7. PubMed 25109530 ↗
  • Bagga D, Aigner CS, Reichert JL, Cecchetto C, Fischmeister FPS, Holzer P, Moissl-Eichinger C, Schopf V. Influence of 4-week multi-strain probiotic administration on resting-state functional connectivity in healthy volunteers. Eur J Nutr. 2019 Aug;58(5):1821-1827. doi: 10.1007/s00394-018-1732-z. Epub 2018 May 30. PubMed 29850990 ↗

Individual participant data

Plan to share: No — This study will be carried out in a single center. Therefore, fecal samples sent for microbiota analysis and data for statistical analyses will be identified by numbers allocated in the protocol and not contain identifiable information.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 8, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07439978
Responsible party
Sponsor
First posted
Feb 27, 2026
Start date
Apr 2026 (estimated)
Primary completion
Jun 2026 (estimated)
Completion
Aug 2026 (estimated)
Last update
May 8, 2026

Study contacts

Werd Al-Najim, PhD
Contact
werd.al-najim@ucd.ie
+353 0864117842
Ahmed Al-Humadi, PhD
Contact
ahmed.al-humadi@ucd.ie
+353 083 0994008
Carel Le Roux, PhD
principal investigator · St Vincent's University Hospital, Ireland

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.

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