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The Effect of Probiotic Supplementation on SARS-CoV-2 Antibody Response After COVID-19

Exploratory Study on the Effects of Probiotic Supplementation on SARS-CoV-2 Antibody Response in Healthy Adults

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04734886
Enrollment
161
Registered
2021-02-02
Start date
2020-11-27
Completion date
2021-09-13
Last updated
2021-10-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid19

Brief summary

This study will explore how a well-known probiotic strain L. reuteri DSM 17938 impacts SARS-CoV-2 specific antibody response upon and after infection in healthy adults.

Detailed description

After giving their informed consent, the study subjects will complete screening procedures to assess their eligibility for the study (Visit 1). Participants deemed suitable for the study will be randomized into two study arms (placebo, probiotic) before undergoing a baseline visit (Visit 2) before the start of the intervention period. During the 6-month intervention period, the participants will attend study visits at 3 months (Visit 3) into the intervention as well as at the end of intervention (at 6 months, Visit 4). Blood, saliva, and faecal samples will be collected at visits 2-4. In addition to sampling, during the whole intervention period, the participants will fill out a weekly questionnaire in which they are asked to record any possible symptoms of COVID-19. The participants' dietary habits are assessed via a food frequency questionnaire (FFQ) before the start of the intervention period. Also, the participants are asked to maintain their habitual diet and lifestyle as well as not to consume any other probiotic or prebiotic supplements.

Interventions

DIETARY_SUPPLEMENTL. reuteri DSM 17938 + vitamin D

1 \* 10\^8 CFU of L. reuteri DSM 17938 + 10 ug vitamin D3, two capsules per day for 6 months

DIETARY_SUPPLEMENTPlacebo + vitamin D

Placebo tablet + 10 ug vitamin D3, Similar in shape and taste to intervention capsules but without the probiotic components, two capsules per day over six weeks

Sponsors

BioGaia AB
CollaboratorINDUSTRY
Örebro University, Sweden
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes

Inclusion criteria

1. Signed informed consent 2. Age between 18-60

Exclusion criteria

1. Previous diagnosis of COVID-19 (by positive PCR) or previous confirmation of seropositivity to SARS-CoV-2 2. Body Mass Index over 35 or under 16 3. Current diagnosis of cancer or ongoing cancer treatment in the last 12 months 4. Diabetes mellitus 5. Cardiovascular disorder in need of pharmaceutical treatment 6. Chronic kidney disease 7. Chronic lung disease with decreased lung capacity 8. Chronic liver disease with liver cirrhosis 9. Current diagnosis of dementia, severe depression, major psychiatric disorder, or other incapacity for adequate cooperation 10. Chronic neurological/neurodegenerative disease (e.g. Parkinson's disease) 11. Decreased function of the adrenal cortex (e.g. Addison's disease) 12. Autoimmune disease (e.g. rheumatoid arthritis) 13. Chronic pain syndromes (e.g. fibromyalgia) 14. Pregnancy or breast-feeding 15. Immunodeficiency due to disease or ongoing medical treatment 16. Regular intake of anti-inflammatory and/or other immunosuppressive medication within the last 3 months 17. Use of anti-depressants within the last 3 months 18. Antimicrobial treatment within the last 12 weeks before baseline sampling 19. Regular intake of probiotics, as well as nutritional supplements or herb products that might affect intestinal function within the last 4 weeks if the investigator considers that those could affect study outcome 20. Inability to maintain current diet and lifestyle during the study period 21. Alcohol or drug abuse 22. Any clinically significant present or past disease/condition which the investigator considers to possibly interfere with the study outcome or increase the risk for severe form of COVID-19

Design outcomes

Primary

MeasureTime frameDescription
SARS-CoV-2 specific antibodies3 months (interim analysis) or at 6 monthsChange in SARS-CoV-2 specific IgG/IgM antibodies in serum between the study arms

Secondary

MeasureTime frameDescription
Tn antigen antibodies3 months + 6 monthsChange in anti-Tn levels in serum between the study arms
Intestinal inflammation3 months + 6 monthsChange in faecal calprotectin levels between the study arms
Intestinal barrier function3 months + 6 monthsChange in I-FABP levels in plasma between the study arms
Indirect marker of intestinal permeability3 months + 6 monthsChange in LBP levels in plasma between the study arms
Maintenance of SARS-CoV-2 seroconversion in seropositive individuals3 months + 6 monthsChange in the maintenance of SARS-CoV-2 specific IgG/IgM antibody levels in serum between the study arms
Duration of COVID-19 symptoms measured by a weekly symptom questionnaire3 months + 6 monthsChange in duration of COVID-19 related symptoms between the study arms
Severity of COVID-19 symptoms measured by Ordinal Scale for Clinical Improvement (scale 0-7, a lower score corresponds to a better outcome)3 months + 6 monthsChange in severity of COVID-19 related symptoms between the study arms
Secretory IgA (sIgA) antibodies3 months + 6 monthsChange in sIgA levels in saliva between the study arms
Blood group A antigen antibodies3 months + 6 monthsChange in anti-A levels in serum between the study arms
Blood group B antigen antibodies3 months + 6 monthsChange in anti-B levels in serum between the study arms
Innate immune system activation3 months + 6 monthsChange in high-sensitive C-reactive protein (hs-CRP) levels in plasma between the study groups
Cytokines3 months + 6 monthsChange in TNF-a, IFN-y, IL-1B, IL-4, IL-6, IL-8, IL-10 levels in serum between the study groups
Total antibodies3 months + 6 monthsChange in total IgG and IgM levels in serum between the study groups
T cell activation3 months + 6 monthsChange in the proportion of SARS-CoV-2 specific T cells of all T cells in blood between the study arms
B cell activation3 months + 6 monthsChange in the proportion of SARS-CoV-2 specific B cells of all B cells in blood between the study arms

Other

MeasureTime frameDescription
Composition of intestinal microbiota and inflammatory profile3 months + 6 monthsCorrelation of intestinal microbiota composition to TNF-a, IFN-y, IL-1B, IL-4, IL-6, IL-8, IL-10 levels in serum
Composition of intestinal microbiota and COVID-19 related symptoms3 months + 6 monthsCorrelation of intestinal microbiota composition to duration and severity of COVID-19 related symptoms
Composition of intestinal microbiota and SARS-CoV-2 specific antibody3 months + 6 monthsCorrelation of intestinal microbiota composition to SARS-CoV-2 specific antibody levels in serum

Countries

Sweden

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026